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While there are numerous reports on surgical techniques and materials for bone grafting, limited methods are available to enhance the body's inherent capacity to heal bones. Here we investigated microRNA-199a (miR-199a), a molecular that promotes osteoblast differentiation and bone healing. To construct a miR-199a delivery complex, miR-199a-5p mimics were coated with mesoporous silica nanoparticles (MSNs) following modified with polyethyleneimine (PEI) and peptide WEAKLAKALAKALAKHLAKALAKALKACEA (KALA) to obtain 199a-5p-loaded MSN-PEI-KALA. Nanoparticle complexes are assessed for particle size and zeta potential using transmission electron microscopy and dynamic light scattering. Then MC3T3-E1 cells are exposed to MSN_miR-199a-5p @PEI-KALA. The impact of MSN_miR-199a-5p@PEI-KALA at varying concentrations on cell viability is assessed using Cell Counting Kit-8. Cell uptake and distribution were analyzed by double fluorescent staining with fluorescein amidite-labeled MSN_miR-199a@PEI-KALA and lysosome labeling. On day 7 after osteogenic induction, alkaline phosphatase (ALP) staining was conducted. The findings indicated that the nanoparticle complexes encapsulating PEI and peptide exhibited an augmentation in both particle size and zeta potential. At a dosage of 10 μg/mL, MSN_miR-199a@PEI-KALA displayed the lowest cytotoxicity compared to the control group. MC3T3-E1 cells treated with MSN_miR-199a-5p@PEI-KALA exhibited intensified ALP staining and elevated mRNA expression levels of ALP, runt-related transcription factor 2, and osteopontin, suggesting the involvement of miR-199a-5p-loaded MSN-PEI-KALA in osteogenic differentiation. The successful construction of the delivering complex MSN_miR-199a@PEI-KALA in present research highlights the promise of this biomaterial carrier for the application of miRNAs in treating bone defects. [ABSTRACT FROM AUTHOR]

Obeticholic acid (OCA), a farnesoid X receptor (FXR) agonist with favorable effects on fatty and glucose metabolism, has been considered the leading candidate drug for nonalcoholic steatohepatitis (NASH) treatment. However, its limited effectiveness in resolving liver fibrosis and lipotoxicity-induced cell death remains a major drawback. Ferroptosis, a newly recognized form of cell death characterized by uncontrolled lipid peroxidation, is involved in the progression of NASH. Nitric oxide (NO) is a versatile biological molecule that can degrade extracellular matrix. In this study, we developed a PEGylated thiolated hollow mesoporous silica nanoparticles (MSN) loaded with OCA, as well as a ferroptosis inhibitor liproxsatin-1 and a NO donor S -nitrosothiol (ONL@MSN). Biochemical analyses, histology, multiplexed flow cytometry, bulk-tissue RNA sequencing, and fecal 16S ribosomal RNA sequencing were utilized to evaluate the effects of the combined nanoparticle (ONL@MSN) in a mouse NASH model. Compared with the OCA-loaded nanoparticles (O@MSN), ONL@MSN not only protected against hepatic steatosis but also greatly ameliorated fibrosis and ferroptosis. ONL@MSN also displayed enhanced therapeutic actions on the maintenance of intrahepatic macrophages/monocytes homeostasis, inhibition of immune response/lipid peroxidation, and correction of microbiota dysbiosis. These findings present a promising synergistic nanotherapeutic strategy for the treatment of NASH by simultaneously targeting FXR, ferroptosis, and fibrosis. The PEGylated and thiolated hollow mesoporous silica nanoparticles (MSN), loaded with OCA, S -nitrosothiol, and liproxstatin-1, exhibit potent therapeutic action against NASH by simultaneously targeting FXR, ferroptosis, and fibrosis. [Display omitted] [ABSTRACT FROM AUTHOR]

Antifouling membranes were developed by encapsulating amino-functionalized nano-silica in polymeric mixes of polyethersulfone (PES) and polyvinyl pyrrolidone (PVP). Subsequently, the membranes were modified with a nano-Ag/PVP coating layer. The membranes' performance was assessed against synthetic whey solutions model to mimic dairy wastewater. Various techniques were harnessed to evaluate the membranes' composition, structure and morphology, including SEM, XPS, XRD, AFM, mechanical characteristics, porosities and contact angles. Findings indicated that nanocomposite made with 1.5 % amino-functionalized nano-silica (M3) revealed optimum performance and was capable to separate 90 % of the whey in the feed along with a permeate flux of 238 L/m2.h, when the feed whey concentration was 0.4°Brix. the equivalent membrane but coated with a nano-Ag /PVP layer (M3S) displayed a trivial drop in permeate flux (229.3 L/m2.h) comparing to uncoated one. Nonetheless, the addition of the coating boosted the separation efficiency up to 99.7 % of the whey in the feed. The fouling test indicated that the coated membrane (M3S) had superior antifouling property, where flux recovery ratio (FRR) hit 99.5 % with a diminution in the backwash rate. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO)-based gas therapy approaches are promising in the treatment of infections; however, these strategies are hindered by poor delivery to the target site, which leads to unsatisfactory effects. In this study, we developed a NO-controlled platform (SCM@HA) via NO-generating mesoporous silica nanoparticles co-doped with sodium nitroprusside and copper sulphide to control NO production under near-infrared (NIR)-laser irradiation. Irradiation with an 808 nm NIR laser rapidly triggered the release of NO from the particles to actualise gas therapy. Photothermal therapy (PTT) also increased the local microenvironment temperature, and the close relationship between chemodynamic therapy (CDT) and temperature suggests that the increasing temperature facilitates in its working. The hydroxyl radicals generated by CDT can destroy the structure of bacteria in acidic environments. The germicidal activity of the nanoparticles was determined by the combined action of PTT, CDT, and NO-based gas therapy. The nanoparticles showed bactericidal activity in vitro against bacterial strains Staphylococcus aureus (S. aureus) and Salmonella typhimurium (S. typhimurium). Finally, the anti-infective efficacy in vivo in S. aureus -infected mouse model was demonstrated. Thus, the synergistic antimicrobial effects of NO-generating silica nanoparticles have good potential for the non-antibiotic treatment of bacterial infections in wounds. Bacterial infections and resistance are challenging health threats. Therefore, the development of an antibiotic-independent method is essential for the treatment of wound bacterial infections. In this study, NO-generating nanoparticles loaded with sodium nitroprusside in copper sulphide-doped mesoporous silica were prepared to control the long-term release of NO using near-infrared laser, which has good efficacy of PTT and CDT. The bactericidal effects of as-prepared nanoparticles against S. aureus and S. typhimurium have been well elucidated. This study proposes a feasible method in the field of NO-based therapy, thus paving the way that will benefit for the treatment of bacterial infections in wounds. [Display omitted] [ABSTRACT FROM AUTHOR]

Cellular senescence is implicated in the occurrence and progression of multiple age-related disorders. In this context, the selective elimination of senescent cells, senolysis, has emerged as an effective therapeutic strategy. However, the heterogeneous senescent phenotype hinders the discovery of a universal and robust senescence biomarker that limits the effective of senolytic with off-target toxic effects. Therefore, the development of more selective strategies represents a promising approach to increase the specificity of senolytic therapy. In this study, we have developed an innovative nanodevice for the selective elimination of senescent cells (SCs) based on the specific enzymatic activity of the senescent secretome. The results revealed that when senescence is induced in proliferating WI-38 by ionizing radiation (IR), the cells secrete high levels of matrix metalloproteinase-3 (MMP-3). Based on this result, mesoporous silica nanoparticles (MSNs) were loaded with the senolytic navitoclax (Nav) and coated with a specific peptide which is substrate of MMP-3 (NPs(Nav)@MMP-3). Studies in cells confirmed the preferential release of cargo in IR-induced senescent cells compared to proliferating cells, depending on MMP-3 levels. Moreover, treatment with NPs(Nav)@MMP-3 induced a selective decrease in the viability of SCs as well as a protective effect on non-proliferating cells. These results demonstrate the potential use of NPs to develop enhanced senolytic therapies based on specific enzymatic activity in the senescent microenvironment, with potential clinical relevance. The common β-galactosidase activity has been exploited to develop nanoparticles for the selective elimination of senescent cells. However, the identification of new senescent biomarkers is a key factor for the development of improved strategies. In this scenario, we report for the first time the development of NPs targeting senescent cells based on specific enzymatic activity of the senescent secretome. We report a navitoclax-loaded nanodevice responsive to the matrix metalloproteinase-3 (MMP-3) associated with the senescent phenotype. Our nanosystem achieves the selective release of navitoclax in an MMP-3-dependent manner while limiting off-target effects on non-senescent cells. This opens the possibility of using nanoparticles able to detect an altered senescent environment and selectively release its content, thus enhancing the efficacy of senolytic therapies. [Display omitted] [ABSTRACT FROM AUTHOR]

Foam stability tests were performed using sodium dodecyl sulfate (SDS) surfactant and SiO2 nanoparticles as foaming system at different asphaltene concentrations, and the half-life of CO2 foam was measured. The mechanism of foam stability reduction in the presence of asphaltene was analyzed by scanning electron microscope (SEM), UV adsorption spectrophotometric concentration measurement and Zeta potential measurement. When the mass ratio of synthetic oil to foam-formation suspension was 1:9 and the asphaltene mass fraction increased from 0 to 15%, the half-life of SDS-stabilized foams decreased from 751 s to 239 s, and the half-life of SDS/silica-stabilized foams decreased from 912 s to 298 s. When the mass ratio of synthetic oil to foam-formation suspension was 2:8 and the asphaltene mass fraction increased from 0 to 15%, the half-life of SDS-stabilized foams decreased from 526 s to 171 s, and the half-life of SDS/silica-stabilized foams decreased from 660 s to 205 s. In addition, due to asphaltene-SDS/silica interaction in the aqueous phase, the absolute value of Zeta potential decreases, and the surface charges of particles reduce, leading to the reduction of repulsive forces between two interfaces of thin liquid film, which in turn, damages the foam stability. [ABSTRACT FROM AUTHOR]

The immune system's role in tumor growth and spread has led to the importance of activating immune function in tumor therapy. We present a strategy using an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform (M1mDDTF) to synergistically reinforce immunogenic cell death (ICD) and transform tumor-associated macrophages (TAMs) against tumors. The M1mDDTF nanoparticles consist of doxorubicin-loaded dendritic mesoporous silica nanoparticles chelated with FeIII-tannic acid (FeIIITA) and coated with M1-type macrophage membranes. In the acidic tumor microenvironment, FeIIITA releases Fe2+ and generates ·OH, aided by near infrared irradiation for enhanced doxorubicin release. Furthermore, the M1mDDTF nanoplatform not only directly kills tumor cells but stimulates ICD, which can increase the proportion of CD86+ CD80+ cells and promote dendritic cell maturation. Particularly, the M1mDDTF nanoplatform can also promote the gradual polarization of TAMs into the M1-type and promote tumor cell killing. This study demonstrates the safety and multifunctionality of M1mDDTF nanoparticles, highlighting their potential for clinical tumor treatment. Malignant tumors are a global concern and a major cause of death. Nanoparticles' passive targeting is ineffective and hindered by reticuloendothelial system clearance. Therefore, enhancing nanoparticle accumulation in tumors while minimizing toxicity is a challenge. Coating nanoparticles with cell membranes enhances biocompatibility, immune evasion, and specific targeting. This approach has led to the development of numerous cell membrane-mimicking nanomaterials with remarkable properties and functions. This study developed an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform, boosting immunogenic cell death and transforming tumor-associated macrophages. Tannic acid in the tumor microenvironment reduced Fe3+ to Fe2+, generating ·OH. M1mDDTF nanosystem induced M1-type macrophage polarization, inhibiting tumor growth and triggering immune cell death. Safe and versatile, these M1mDDTF nanoparticles hold promise for clinical tumor treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

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The promise of regeneration therapy for restoration of damaged myocardium after cardiac ischemic injury relies on targeted delivery of proliferative molecules into cardiomyocytes whose healing benefits are still limited owing to severe immune microenvironment due to local high concentration of proinflammatory cytokines. Optimal therapeutic strategies are therefore in urgent need to both modulate local immunity and deliver proliferative molecules. Here, we addressed this unmet need by developing neutrophil-mimic nanoparticles NM@miR, fabricated by coating hybrid neutrophil membranes with artificial lipids onto mesoporous silica nanoparticles (MSNs) loaded with microRNA-10b. The hybrid membrane could endow nanoparticles with strong capacity to migrate into inflammatory sites and neutralize proinflammatory cytokines and increase the delivery efficiency of microRNA-10b into adult mammalian cardiomyocytes (CMs) by fusing with cell membranes and leading to the release of MSNs-miR into cytosol. Upon NM@miR administration, this nanoparticle could home to the injured myocardium, restore the local immunity, and efficiently deliver microRNA-10b to cardiomyocytes, which could reduce the activation of Hippo-YAP pathway mediated by excessive cytokines and exert the best proliferative effect of miR-10b. This combination therapy could finally improve cardiac function and mitigate ventricular remodeling. Consequently, this work offers a combination strategy of immunity modulation and proliferative molecule delivery to boost cardiac regeneration after injury. Hybrid neutrophil-mimic nanoparticle NM@miR could realize absorption of proinflammatory cytokines and delivery of proliferative microRNA together, which holds huge potential for the regenerative treatment of cardiac ischemic diseases. [Display omitted] [ABSTRACT FROM AUTHOR]

Fast-dissolving microneedles (DMNs) hold significant promise for transdermal drug delivery, offering improved patient compliance, biocompatibility, and functional adaptability for various therapeutic purposes. However, the mechanical strength of the biodegradable polymers used in DMNs often proves insufficient for effective penetration into human skin, especially under high humidity conditions. While many composite strategies have been developed to reinforce polymer-based DMNs, simple mixing of the reinforcements with polymers often results in ineffective penetration due to inhomogeneous dispersion of the reinforcements and the formation of undesired micropores. In response to this challenge, this study aimed to enhance the mechanical performance of hyaluronic acid (HA)-based microneedles (MNs), one of the most commonly used DMN systems. We introduced in situ precipitation of silica nanoparticles (Si) into the HA matrix in conjunction with conventional micromolding. The precipitated silica nanoparticles were uniformly distributed, forming an interconnected network within the HA matrix. Experimental results demonstrated that the mechanical properties of the HA–Si composite MNs with up to 20 vol% Si significantly improved, leading to higher penetration efficiency compared to pure HA MNs, while maintaining structural integrity without any critical defects. The composite MNs also showed reduced degradation rates and preserved their drug delivery capabilities and biocompatibility. Thus, the developed HA–Si composite MNs present a promising solution for efficient transdermal drug delivery and address the mechanical limitations inherent in DMN systems. HA–Si composite dissolving microneedle (DMN) systems were successfully fabricated through in situ precipitation and conventional micromolding processes. The precipitated silica nanoparticles formed an interconnected network within the HA matrix, ranging in size from 25 to 230 nm. The optimal silica content for HA–Si composite MN systems should be up to 20 % by volume to maintain structural integrity and mechanical properties. HA–Si composite MNs with up to 20 % Si showed improved penetration efficiency and reduced degradation rates compared to pure HA MNs, thereby expanding the operational window. The HA–Si composite MNs retained good drug delivery capabilities and biocompatibility. [Display omitted] [ABSTRACT FROM AUTHOR]

There is an increasing industrial demand to improve the thermal characteristics of fluids as they flow over stretching/shrinking and rotating surfaces. Heat transfer liquids, thermal exchangers, and coolants in electronics are examples of applicable applications. The thermal transport characteristics of hybrid nanofluids are improved by the inclusion of composite nanoparticles. Because the hybrid nanofluids can improve thermal conductivity compared to traditional fluids. However, several investigations are still needed to fully comprehend its features. Hence, this study investigates the fluid flow and thermal transport properties of thermally radiated hybrid alumina-silica/methanol nanofluid in a three-dimensional domain through a permeable porous shrinking surface. The hybrid nanofluid flow model of PDEs is transformed into ODEs by using similarity conversion, which is then numerically solved in MATLAB using the bvp4c solver. The characteristics of hybrid nanofluid velocity, thermal distribution, friction drag, and heat transport rate are graphically depicted for various physical flow parameters. The outcomes reveal that the range of first and second solutions can be augmented by increasing nanoparticle volume percentage. Furthermore, the results suggest that increasing the suction parameter can improve the effective heat transfer performance of the hybrid nanofluid whereas thermal radiation and heat source/sink parameters have no effect on delaying the boundary layer separation. [ABSTRACT FROM AUTHOR]

In this work, waste nitrile rubber (NBR) was radio-chemo-mechanically devulcanized and used as oil/seawater separator. Pure and surface modified silica nanoparticles were applied to the new and recycled NBR compounds at different contents (i.e. 1, 2, 3, 5 and 10 wt%). The surface modification of nanoparticles was performed using triethoxyvinylsilane (TEVS) at different concentrations (i.e. 1, 5 and 10X). The rheological/mechanical properties and water/oil contact angles (WCA/OCA) of the new and recycled NBR based nanocomposites were evaluated. The results showed that using modified silica nanoparticles (at 5 wt% loading content) caused increment in the WCA from 89.89 and 95.3° to 151.56 and 153.3° and decrease in the OCA from 73.39 and 71.3° to 14.1 and 11.1° for new and recycled NBRs, respectively. It was also found that durability of sorbent against oil absorption–desorption cycles declined using the recycled rubber instead of new NBR compound (i.e. from 1000 to 700 cycles), but the oil absorption capacity enhanced (i.e. from 2.2 to 2.4 g/g). The oil separation efficiencies (OSE) of the modified nanocomposites were more than 99%. It was shown that using modified nanoparticles in RNBR caused 50% decrement in the Payne effect and 33% enhancement in the chemical/physical bonds, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] In the present work, uncoated silica nanoparticles (SiO 2 NPs) and polyethylenimine (PEI) coated silica nanoparticles (SiO 2 -g-PEI NPs) were individually impregnated within a polyethersulfone (PES) polymeric matrix via the classical phase inversion technique. The performance of both prepared mixed matrix membranes was compared by mebeverine hydrochloride (MBV) separation from aqueous pharmaceutical wastewater. The nanoparticles content varied between 0.7 and 1 % in the polymeric matrix to probe their optimum performance. A comprehensive characterization for both NPs and nanocomposite membranes was performed by a series of characterization tools including Fourier Transform Infrared Spectroscopy, Field Emission Scanning Electron Microscopy, Energy Dispersive X-ray Analysis spectroscopy, Contact Angle (CA) and Tensile Strength. For first time, the suggested interaction mechanism of both PES/SiO 2 and PES/SiO 2 -g-PEI membrane's surface with the feed molecules has been elucidated. Results revealed that the nanocomposite membrane prepared with 0.9 wt% SiO 2 -g-PEI has possessed the optimum performance in terms of surface porosity (89.96 ± 1.7 %), CA (49 ± 1.8°), mean pore radius (13.55 ± 0.41 nm), and mechanical properties (tensile strength 10.16 MPa). Almost complete removal (up to 99.99 %) against MBV molecules was observed together with a high water flux reached (140 ± 1.28 LMH). Besides, during the prolonged operation (up to 250 hrs), this optimum membrane (DS0.9) manifested a stable performance along with a remarkable flux recovery ratio (95.4 %). For pharmaceutical pollutants removal, the DS0.9 membrane performance has surpassed those attained by nascent PES and mixed matrix membranes modified with SiO 2. The study enclosed novel and powerful insights about the potential of SiO 2 -g PEI in tailoring membrane performance. [ABSTRACT FROM AUTHOR]

Image-guided stimulus-responsive theranostics are beneficial for identifying malignant lesions and integrating multiple cell-killing mechanisms to enhance tumor cell clearance. Herein, an intelligent dual-responsive nanostructure (HSPMH-DOX) was developed for magnetic resonance imaging (MRI)-guided synergistic chemo-photothermal therapy (PTT) and chemodynamic therapy (CDT). The core-shell nanostructure was synthesized by layering polydopamine (PDA), manganese oxide (MnO 2), and hyaluronic acid (HA) onto drug-loaded hollow mesoporous silica nanoparticles (HS). The constructed nanoagent has both endogenous and external dual responses. The tumor microenvironment (pH/GSH) can trigger the degradation of gatekeeper (MnO 2 and PDA), resulting in the release of anti-tumor drugs, whereas external near-infrared light irradiation can accelerate the degradation process and generate local overheating, resulting in PTT. Notably, MnO 2 can not only consume intracellular GSH to enhance CDT but also release Mn2+ for precise localization of tumor tissues using MRI. Both in vitro and in vivo experiments showed that the prepared dual-response nanoagent satisfied biocompatibility, targeting, and the great efficiency of MRI-guided combined therapy. In animal models, combining chemo-PTT and CDT can eradicate tumors in less than two weeks. This work could pave the way for a wide range of stimulus-responsive synergistic theranostic applications, including MRI, chemo-photothermal therapy, and chemodynmic therapy. Low bioavailability and severe side effects remain the major limitations of conventional cancer chemotherapy. Image-guided combination therapy can alleviate these problems and improve tumor-specific therapy. In the present study, the anticancer drug doxorubicin was encapsulated in a core-shell hollow mesoporous silica nanostructure (HSPMH-DOX), enabling MRI-guided targeted release under both endogenous and external dual stimuli. Moreover, the photothermal and nanoenzymatic effects of nanomedicine can cause local overheating in the tumor and amplify the intracellular CDT effect, accelerating tumor eradication. Systematic evaluations in vitro and in vivo confirmed that nanomedicine enables highly effective MRI-guided synergistic chemo-photothermal and chemodynamic therapy. This work offers a promising therapeutic strategy for precise anti-tumor applications. [Display omitted] [ABSTRACT FROM AUTHOR]

In the last few years, nanotechnology has revolutionized the potential treatment of different diseases. However, the use of nanoparticles for drug delivery might be limited by their immune clearance, poor biocompatibility and systemic immunotoxicity. Hypotheses for overcoming rejection from the body and increasing their biocompatibility include coating nanoparticles with cell membranes. Additionally, source cell-specific targeting has been reported when coating nanoparticles with tumor cells membranes. Here we show that coating mesoporous silica nanoparticles with membranes derived from preosteoblastic cells could be employed to develop potential treatments of certain bone diseases. These nanoparticles were selected because of their well-established drug delivery features. On the other hand MC3T3-E1 cells were selected because of their systemic migration capabilities towards bone defects. The coating process was here optimized ensuring their drug loading and delivery features. More importantly, our results demonstrated how camouflaged nanocarriers presented cellular selectivity and migration capability towards the preosteoblastic source cells, which might constitute the inspiration for future bone disease treatments. This work presents a new nanoparticle formulation for drug delivery able to selectively target certain cells. This approach is based on Mesoporous Silica Nanoparticles coated with cell membranes to overcome the potential rejection from the body and increase their biocompatibility prolonging their circulation time. We have employed membranes derived from preosteoblastic cells for the potential treatment of certain bone diseases. Those cells have shown systemic migration capabilities towards bone defects. The coating process was optimized and their appropriate drug loading and releasing abilities were confirmed. The important novelty of this work is that the camouflaged nanocarriers presented cellular selectivity and migration capability towards the preosteoblastic source cells, which might constitute the inspiration for future bone disease treatments. [Display omitted] [ABSTRACT FROM AUTHOR]

Osteomyelitis is a hard-to-treat infection of the bone and bone marrow that is mainly caused by Staphylococcus aureus , with an increasing incidence of methicillin-resistant S. aureus (MRSA). Owing to the aggressiveness of these bacteria in colonizing and destroying the bone, systemic antibiotic treatments fail to eradicate the infection. Instead, it normally entails surgery to remove the dead or infected bone. In this work, we report bone-targeted mesoporous silica nanoparticles for the treatment of osteomyelitis. The nanoparticles have been engineered with a functional gelatine/colistin coating able to hamper premature release from the mesopores while effectively disaggregating the bacterial biofilm. Because antibiotic resistance is a global emergency, we have designed two sets of identical nanoparticles, carrying each of them a clinically relevant antibiotic, that have demonstrated to have synergistic effect. The bone-targeted nanoparticles have been thoroughly evaluated in vitro and in vivo , obtaining a notable reduction of the amount of bacteria in the bone in just 24 h after only one dose, and paving the way for localized, nanoparticle-mediated treatment of MRSA-caused osteomyelitis. In this work, we propose the use of bone-targeted mesoporous silica nanoparticles to address S. aureus -caused osteomyelitis that render synergistic therapeutic effect via multidrug delivery. Because the bacterial biofilm is responsible for an aggressive surgical approach and prolonged antibiotic treatment, the nanoparticles have been functionalized with a functional coating able to both disaggregate the biofilm, hamper premature antibiotic release and protect the intact bone. These engineered nanoparticles are able to effectively target bone tissue both in vitro and in vivo , showing high biocompatibility and elevated antibacterial effect. [Display omitted] [ABSTRACT FROM AUTHOR]

Silica nanoparticles (SiNPs) are widely used in various commercial applications, which inevitably increase the risk of human exposure. It's reported that SiNPs have toxic effects on fertility, however, the specific mechanism of female reproductive toxicity induced by SiNPs remains confusing. In this study, female C57BL/6 mice at the age of 8 weeks were administrated orally with SiNPs at doses of 0, 3, and 10 mg/kg bw. every day in the presence/absence of NAC for eight weeks. The results showed that SiNPs could cause damage to ovaries and reduce the number of ovarian follicles, which led to disruption of sex hormone, altered estrous cyclicity and decreased female fertility. In addition, SiNPs induced oxidative stress in the ovary, as manifested by increased ROS and MDA levels, decreased SOD activity and inhibition of the Nrf2/HO-1 signaling pathway. Further study revealed that exposure to SiNPs resulted in mitochondrial dysfunction and promoted autophagy mediated by PI3K/AKT/mTOR and PINK1/Parkin signaling pathways. Meanwhile, apoptosis is also involved in SiNPs-induced cell death in a cooperative and synchronized manner, as evidenced by an increase in apoptosis-positive cells and activation of the ATM/p53-mediated apoptotic pathway. The supplementation of NAC restored most of the reproductive characteristics of the mice to its physiological range. These results demonstrated that SiNPs could cause ovarian damage via inducing oxidative stress and mitochondrial dysfunction, which led to autophagy and apoptosis, and ultimately resulting in abnormal folliculogenesis and female subfertility. • SiNPs exposure causes damage to the structure of ovarian tissue in mice. • SiNPs exposure perturbs the process of folliculogenesis and reduces female fertility. • SiNPs exposure triggers autophagy and apoptosis in the ovary of mice via inducing oxidative stress. [ABSTRACT FROM AUTHOR]

The disease burden of non-alcoholic fatty liver disease (NAFLD) is increasing worldwide. Emerging evidence has revealed that silica nanoparticles (SiNPs) could disorder the liver lipid metabolism and cause hepatotoxicity, but the underlying mechanism remains unknown. The purpose of this study is to elucidate the molecular mechanism of hepatic lipid metabolism disorder caused by SiNPs, and to reveal the role of ferroptosis in SiNPs-induced hepatotoxicity. To explore the phenotypic changes in liver, the wild-type C57BL/6J mice were exposed to different doses of SiNPs (5, 10, 20 mg/kg·bw) with or without melatonin (20 mg/kg·bw). SiNPs accelerated hepatic oxidative stress and promoted pathological injury and lipid accumulation, resulting in NAFLD development. Melatonin significantly inhibited the oxidative damage caused by SiNPs. Then, the hepatocytes were treated with SiNPs, the ferroptosis inducer and inhibitor, respectively. In vitro, SiNPs (25 μg/mL) generated mitochondrial and intracellular Fe2+ accumulation and lipid peroxidation repair ability impairment, decreased the activity of GPX4 through ACSL4/p38 MAPK signaling pathway, resulting in ferroptosis of hepatocytes. Notably, Erastin (the ferroptosis activator, 5 μM) increased the sensitivity of hepatocytes to ferroptosis. Ferrostatin-1 (Fer-1, the ferroptosis inhibitor, 5 μM) restored GPX4 activity and protected against deterioration of lipid hydroperoxides (LOOHs) to salvage SiNPs-induced cytotoxicity. Finally, the liver tissue conditional ACSL4 knockout (cKO) mice and ACSL4-KO hepatocytes were adopted to further identify the role of the ACSL4-mediated ferroptosis on SiNPs-induced NAFLD development. The results displayed ACSL4 knockout could down-regulate the lipid peroxidation and ferroptosis, ultimately rescuing the progression of NAFLD. In summary, our data indicated that ACSL4/p38 MAPK/GPX4-mediated ferroptosis was a novel and critical mechanism of SiNPs-induced NAFLD. [Display omitted] • SiNPs cause oxidative stress, lipid accumulation and peroxidation in vivo , resulted in fatty liver disease. • SiNPs-triggered ACSL4 over-expression contributed to Fe2+ release and p38 MAPK upregulation in vivo and in vitro. • Activation of the p38 MAPK pathway deprives GPX4 activity and aggravates the lipid peroxidation in vivo. • ACSL4/p38 MAPK/GPX4-mediated ferroptosis plays an important role in SiNPs-induced fatty liver disease. [ABSTRACT FROM AUTHOR]

• Hydrophilic NS-modified PVDF membranes were prepared for oil–water separation • Membrane modified with a PV:NS ratio of 1:3 produces optimum results • Optimized NS-PVA-PVDF membrane demonstrated oil rejection efficiency >95 % • Flux recovery was 0.96/0.92 of the initial flux when exposed to HA/EBT Oily wastewater is the leading cause of water and environmental pollution, but conventional treatments suffer from complexity and low efficiency, and explicitly deal with oil-in-water emulsions. Polyvinylidene fluoride (PVDF) membranes have shown immense potential for separation applications; however, these membranes rapidly foul during the separation of oily wastewater. A simple method is introduced to improve the hydrophilicity of PVDF membranes by decorating their surfaces with acrylic acid-modified nano-silica (NS) nanoparticles, whose surface stability is achieved by crosslinking them with polyvinyl alcohol (PVA). Three distinct oils were employed in this study for oil–water emulsion analysis: vegetable oil, diesel oil, and petroleum ether oil. The antifouling abilities and characterization were elucidated using advanced analytical techniques. The membrane surface became hydrophilic, and the water contact angle reduced from 64 ± 1.45o to 24.3 ± 1.75o. The NS-PVA-PVDF membrane exhibited the oleophobic behavior underwater, with an underwater oil contact angle of 147.6 ± 2.65o. Under optimized conditions, the NS-PVA-PVDF membranes have shown excellent rejection efficiency for different oil-in-water emulsions, including vegetable oil (99.01± 0.64 %), diesel oil (94.61± 0.26 %), and petroleum ether oil-in-water (84.53 ± 0.85 %) emulsions. For a membrane with a 1:3 ratio of PVA to NS particles, organic foulants like humic acid and dye elucidated better performance with 94.79 ± 1.11 and 92.79 ± 1.41 % removal, respectively, along with the flux recovery ratio of 0.96 and 0.92 for humic acid and dye filtration with irreversible fouling of 0.03 and 0.08, respectively. However, the long-term analysis of the optimum membranes showed an overall stable rejection efficiency of >95 % compared with the pristine membrane. The specific rejection efficiency varied for oil emulsion (44.67–50.14 %), humic acid (59.55–67.75 %), and for dye filtration (61.52–73.5 %). These results verify the potential of the modified NS-PVA-PVDF membrane for oil–water separation for practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles (MSNP) were used to trap reservoir fines and adsorption capacity of MSNP was optimized. Box-Behnken design was used to model effect of concentration, time, salinity and pH on adsorption capacity of reservoir fines. Multiple response surface method was applied to optimize any combination of variables at which the maximum adsorption of the reservoir fines occurred. Microstructural analysis shows a mesoporous structure ranging from 2.88 to 44.8 nm with high specific surface area of 332 m2/g and purity of 94%. Pseudo-second order with regression coefficient (R2) of 0.99 shows that the model best defines reservoir fines adsorption. Langmuir isotherm model with R2 of 0.985 best fitted the equilibrium adsorption of kaolinite whereas high R2 of 0.98 and lower sum of squared errors of illite for Freundlich model indicates it is better than Langmuir model. Heterogeneity factor value of 1/ n < 1 and n values of 5–11 shows sufficient site for adsorption. Predicted reservoir fines adsorption with R2 of kaolinite (98.77%) and illite (99.32%) close to unity indicates that the model is highly consistent with the experimental results with high precision and reliability. Experimental and statistical analysis proved that MSNP can fixate reservoir fines and has adequate capacity to be rejuvenated and reused. [ABSTRACT FROM AUTHOR]

Doxorubicin (DOX) widely used in hepatocellular carcinoma (HCC) can induce serious side effects and drug resistance. Herein, we aimed to seek a strategy to improve the efficacy and reduce the side effects of DOX in HCC based on an autophagy inducer drug called isoginkgetin (ISO). The design of multifunctional nanocarriers based on hyaluronic acid-conjugated and manganese-doped mesoporous silica nanoparticles (HM) for the co-delivery of antitumor drugs against HCC provided an effective and promising antitumor strategy. Our results showed that HM@ISO@DOX could efficiently inhibit HCC cell proliferation through activating autophagy through AMPKa-ULK1 pathway. Moreover, intravenous injection of HM@ISO@DOX significantly suppressed HCC tumor progression in nude mouse HCC model. Collectively, our findings revealed an anti-HCC mechanism of HM@ISO@DOX through autophagy and provide an effective therapeutic strategy for HCC. In our study, we constructed a co-delivery system by loading ISO and DOX in the mesoporous channels of manganese-doped mesoporous silica nanoparticles, which could be further conjugated with hyaluronic acid to obtain HM@ISO@DOX. The nanocarriers had been demonstrated to be biodegradable under the acidic and reducing tumor microenvironment, as well as to possess the tumor targeting capability via the conjugated hyaluronic acid. In addition, HM@ISO@DOX enhanced the therapeutic efficacy against human HCC tumor through the combinatorial therapies of chemotherapeutics, Mn2+-mediated chemodynamic therapeutics and autophagic cell death, which might be achieved through AMPK-ULK1 signaling. This work revealed that such a nanomedicine exhibited superior tumor accumulation and antitumor efficiency against HCC with extremely low systemic toxicity in an autophagy-boosted manner. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanoadhesives can achieve tight wound closure by connecting biomacromolecules from both sides. However, previously developed adhesive systems suffered from suboptimal wound healing efficiency due to the lack of interparticle cohesion, sufficient reactive oxygen species (ROS)-scavenging sites, and angiogenesis consideration. Herein, we developed a polymer entangled porous nanoadhesive system to address the above challenge by synergy of three functional components. Firstly, hybrid mesoporous silica nanoparticles with highly integrated polydopamine (MS-PDA) were prepared by templated synthesis. The entangling between PVA polymer and MS-PDA contributed to much stronger cohesion between nanoparticles, which led to 75% larger adhesion strength. As confirmed by in vitro and in vivo evaluations, the highly exposed catechol groups boosted the scavenging activity of ROS (1.8–4.1 fold enhancement as compared with nonporous counterpart). Consequently, more macrophages exhibited anti-inflammatory phenotype, leading to 2–2.6 fold lower pro-inflammatory cytokine levels. Moreover, the sustained release of bioactive SiO 4 4− by the disintegration of nanoparticles contributed to ∼3-fold higher expression of VEGF and enhanced new blood vessel formation, as well as better wound repair. This platform can provide a new paradigm for developing multifunctional nanoadhesive systems in treating skin wounds. PVA polymer entangled mesoporous nanoadhesives of polydopamine (PDA)/silica hybrids with the combination of excellent wound closure effect, boosted ROS-scavenging activity, and significant angiogenesis ability were developed for improving the suboptimal skin wound healing efficiency. This strategy not only greatly advances our ability to rationally integrate repairing elements in nanoadhesives for manipulating combined processes of interfacial events during wound healing, but also offers general implications toward application of polymers to reinforce the adhesion strength in nanoadhesive systems. In addition, our findings on the impacts of pore effects mediated ROS species conversion and polymer entanglement may also trigger great interests and facilitate the development/broad application of therapeutic adhesives. [Display omitted] [ABSTRACT FROM AUTHOR]

To formulate and characterize RF-loaded mesoporous silica nanoparticles (RF@MSN) in adhesive for bonding zirconia ceramic to tooth for potential application in crowns and bridge restorations. RF was loaded inside MSN to produce RF@MSN and doped with adhesive resin. Morphological and spectral characterization of the nanoparticles were studied. RF@MSN in adhesive with two varying concentrations (0.25wt.% and 0.5 wt.%) were studied for the degree of conversion (DC), antimicrobial activity, cytotoxicity, and shear bond strength (SBS) after luting zirconia to tooth dentin samples. After activation with a diode laser, 0.5 wt.% RF@MSN samples showed the least DC scores (39.56 ± 5.54), while the highest SBS scores (1018 ± 78 MPa) were reported by control group. 0.5 wt.% RF@MSN samples showed the highest antimicrobial capacity for adhesive against Streptococcus mutans. Incorporation of RF@MSN in dentin adhesive showed improved mechanical and antibacterial efficacy after photo illumination after bonding zirconia to the tooth structure. [ABSTRACT FROM AUTHOR]

The present study reports a novel technique to synthesise silica nanoparticles through modified sol-gel, ultrasonication, and hydrothermal routes. Physio-chemical and structural characterization was carried out using X-ray diffraction, high resolution scanning electron microscopy, energy dispersive spectroscopy, dynamic light scattering, Fourier transform infrared spectroscopy, ultraviolet-visible, and photoluminescence spectroscopy. The particle size determination revealed the spherical structure of nanoparticles with an average diameter of 85 nm and between 90-170 nm through HRSEM and DLS respectively. Stretching and vibration bands confirming the presence of SiO2 were obtained in FTIR analysis. Spectra from UV-vis and PL spectroscopy were obtained at a maximum wavelength of 233 nm and 555 nm respectively. The anti-microbial effect of SiO2 nanoparticles against E. coli and S. aureus bacteria revealed the appreciable response which renders them for many biomedical applications like drug delivery. The cytotoxicity of SiO2 nanoparticles on human lung epithelial (A549) cell line revealed their non-toxic behavior. [ABSTRACT FROM AUTHOR]

We developed a new ochratoxin A (OTA) aptamer biosensor to promptly detect OTA in food. Mesoporous silica nanoparticles were used as carriers, and aptamers were used as recognition probes and gating molecules. The fluorescent dye rhodamine 6G was loaded into mesoporous silica, and through electrostatic contact, the OTA aptamer was adsorbed on amino-modified mesoporous silica. The fluorescent dye released from the mesopore in the presence of OTA because of the conformational change induced in the aptamer by the target. The amount of ochratoxin was determined by measuring the fluorescence intensity. Our findings revealed a positive relationship between the fluorescence intensity and OTA concentration, with a limit of detection of 0.28 ng mL-1, and the detection range was 0.05-200 ng mL-1. The recovery rate was 80.7%-110.8% in real samples. The proposed approach is suitable for the quantification of other toxins. [ABSTRACT FROM AUTHOR]

The present research was aimed at synthesising and characterising curcumin-loaded zinc oxide nanoparticle-decorated mesoporous silica as a tissue adhesive (Liquid Stitches). The mesoporous silica nanoparticles facilitate adhesion to tissues through the nanobridging effect. The mesoporous silica was synthesised using a sol–gel methodology, and the drug was incorporated using the wetness impregnation method. The platform that was prepared was characterised using infrared spectroscopy, TEM, DSC, XRD, particle size analysis, BET analysis, a tissue model adhesion test, an antimicrobial assay and a wound model in Sprague Dawley rats. The average particle size was found to be 72.4 nm, while the surface area was found to be 654 m2/g. The tissue model adhesion graphs showed significantly different values for the peak load, work done and deformation at peak load, which reflects a difference between the glue strengths of the mesoporous silica nanoparticles and the Cur-ZnO-MSN and the carrier medium (water). The animal study provided a proof of concept by glueing wounds in less than 1 minute and healing the wound within 5 days. [ABSTRACT FROM AUTHOR]

Chronic wounds are not only a burden for patients but also challenging for clinic treatment due to biofilm formation. Here, we utilized the phenomenon that chronic wounds possess an elevated local pH of 8.9 and developed pH-sensitive silica nanoparticles (SiNPs) to achieve a targeted drug release on alkaline wounds and optimized drug utility. Chlorhexidine (CHX), a disinfectant and antiseptic, was loaded into SiNPs as the model drug. The loaded CHX displayed a release 4 - 5 fold higher at pH 8.0 and 8.5 than at pH 6.5, 7.0 and 7.4. CHX-SiNPs furthermore exhibited a distinctive antibacterial activity at pH 8.0 and 8.5 against both Gram-negative and -positive bacterial pathogens, while no cytotoxicity was found according to cell viability analysis. The CHX-SiNPs were further formulated into alginate hydrogels to allow ease of use. The antibacterial efficacy of CHX-SiNPs was then studied with artificial wounds on ex vivo human skin. Treatment with CHX-SiNPs enabled nearly a 4-lg reduction of the viable bacterial cells, and the alginate formulated CHX-SiNPs led to almost a 3-lg reduction compared to the negative controls. The obtained results demonstrated that CHX-SiNPs are capable of efficient pH-triggered drug release, leading to high antibacterial efficacy. Moreover, CHX-SiNPs enlighten clinic potential towards the treatment of chronic wound infections. A platform for controlled drug release at a relatively high pH value i.e. , over 8, was established by tuning the physical structures of silica nanoparticles (SiNPs). Incorporation of chlorhexidine, an antimicrobial agent, into the fabricated SiNPs allowed a distinctive inhibition of bacterial growth at alkaline pHs, but not at acidic pHs. The efficacy of the SiNPs loaded with chlorhexidine in treating wound infections was further validated by utilizing ex vivo human skin samples. The presented work demonstrates clinic potential of employing alkaline pH as a non-invasive stimulus to achieve on-demand delivery of antimicrobials through SiNPs, showcasing a valuable approach to treating bacterial infections on chronic wounds. [Display omitted] [ABSTRACT FROM AUTHOR]

The formation of tortuous filmwise condensation in desalination setup alongside with reduction in thermal conductivity is a challenge accompanied by efficiency loss. This issue is directly influenced by hydrophobicity, which is a function of surface roughness, as well as surface chemistry. In this sense, the hydrophobicity of variant silicone epoxy based nanocomposites was evaluated to identify the optimum proportion composite for surface condensation of desalination setup. To this end, three types of fumed silica with distinct surface chemistry were utilized in a matrix at the weight percentage of 0.5, 1, 1.5, and 2. To investigate the hydrophobicity, roughness, and distribution of reinforcement, a series of characterization techniques, including contact angle, AFM, and FESEM were used. It was found that, in comparison to pure matrix, the nanocomposite modified with 5 wt % of hydrophobic additive and 0.5 wt % of hydrophilic fumed silica nanoparticles (SE/5B/0.5R200) has the highest contact angle (about 35%) and roughness (13 times), due to the migration of nanoparticle onto the surface. Also, coating the condensation surface of the desalination setup with optimum thickness, i.e. 60 × 10−6 m, resulted in the efficiency improvement by about 33 % compared to the uncoated setup, even after 168 hrs. Indeed, dropwise condensation, straight path movement of droplets, besides thermal conductivity adjust the efficiency. • Migration of hydrophilic fumed-silica to the surface of the novel nanocomposites results in a prominent hydrophobicity. • Dropwise condensation, and straight path movement of droplets in a coated desalination set-up improves efficiency (33%). • Thermal resistivity degrades efficiency in a thicker coated desalination set-up even though dropwise condensation occurs. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) is a devastating condition with limited efficacious treatment options. Recent research has revealed the potential of functional nanomedicines to inhibit ferroptosis and reduce inflammatory response, offering a promising therapeutic approach for SCI. Urolithin A (UA) exhibits outstanding antioxidant and anti-inflammatory properties in different neurodegenerative disorders. Intriguingly, whether UA can antagonize ferroptosis remains unknown, and its specific impact on SCI and underlying mechanisms have not been extensively explored. Given the pathological response of esterase overexpression in the SCI microenvironment, taken advantages of nanotechnology in precise targeted delivery, flexible structure design and effective enhancement of drug metabolism pathways, in this study, a novel silica-based integrated nanocarrier is constructed by incorporating carbamate-bridged UA into silica nanoparticles. The resulting PEGylated UA silicon hybrid NPs (PUASi NPs) are sensitive and could be specifically recognized and cleaved by esterase. The findings from both in vitro and in vivo experiments demonstrate that the continuous release of UA from PUASi NPs exhibits notable anti-ferroptotic and anti-inflammatory effects, thus contributing to the improvement of functional recovery in mice suffering from SCI. Collectively, this esterase-activatable nanoprodrug strategy offers an alternative therapeutic regimen for clinical intervention in SCI, with promising prospects for translation into clinical practice. [Display omitted] • PUASi NPs are sensitive and could be specifically recognized and cleaved by esterase. • The sustained release of UA not only inhibit ferroptosis but also protect neuronal cells from neuroinflammatory damage. • PUASi NPs promote nerve regeneration after SCI via reducing ferroptosis and reprogramming inflammatory microenvironment. [ABSTRACT FROM AUTHOR]

[Display omitted] In the current study, sustained release salicylic acid (SA) and ketoconazole (KCZ) loaded silica nanoparticles (SiO 2 -NPs) were encapsulated in natural macromolecule-alginate (ALG) based scaffold through freeze gelation method for an effective treatment of commonly prevailed fatal fungal infections. After statistical optimization by central composite rotatable design (CCRD), the optimized scaffold was subjected to comparative in vitro/in vivo antifungal, skin irritation, wound healing, cytotoxicity, and histopathological evaluations. In physico-chemical characterization performed through X-ray diffraction (p-XRD), Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA), an absolute lack of structural interactions was found between drugs and formulation components. The zeta potential and scanning electron microscopy (SEM) revealed spherical, highly porous negatively charged (–23.1) SiO 2 -NPs having a size distribution of 40–80 nm with successful encapsulation in negatively charged scaffold (-20.2 mV). The entrapment efficiency and drugs release exhibited visible quadratic influence of formulation variables on scaffold. The optimized ALG-scaffold demonstrated comparatively an enhanced in vitro, in vivo antifungal activity, least cytotoxicity and rapid wound healing efficacy in histopathological evaluation by sustained drugs release up to 14-days without any skin irritation effect. The study suggested the potential of alginate scaffold for not only the endurance of drugs loaded SiO 2 -NPs but also for the simultaneous co-delivery of medicaments fulfilling the need of consistent prolonged availability of drugs for better fungal therapeutics. [ABSTRACT FROM AUTHOR]

Achieving the desired efficiency in cuttings transport has always been a challenge during drilling situations due to complex wellbore trajectories and drilling hydraulics. These issues require suitable additives to formulate the drilling muds. Hence, nanocomposite (NC) particles formed from silica and polypropylene was modified by (3-Aminopropyl) triethoxysilane (termed PP-SiO 2 NC-NH 2) and the impact of the concentrations of the PP-SiO 2 NC-NH 2 between 0.4 and 1.2 ppb on the cuttings transport efficiency (CTE) of complex water-based mud (WBM) system was assessed. Mud system containing 0.5 ppb PP-SiO 2 NC-NH 2 on CTE was measured and compared with that of partially hydrolyzed polyacrylamide (PHPA) using sandstone grains of diameters between 0.50 and 3.20 mm at hole angles 0, 30, 45, 60, and 90° with a 42 L/min pump rate. The zeta potential (ζ-potential), particle size distribution, morphology, and temperature resistance of the NC were examined. The ζ-potential data revealed the stability and the long-term stabilization of the modified NC in drilling muds. By adding the concentration of the modified NC into the WBM system, the thinning characteristics and consistency factors were enhanced as the NC concentration increases. Furthermore, the rheological test program reveals that the NC concentrations and 0.5 ppb PHPA increased the shear stress of the WBM with an increase in the shear rate. However, the mud system of PHPA exhibited a larger viscosity, while the NC samples showed a flat viscosity-profile. Also, the NC demonstrated better cuttings recovery than the PHPA product at 0.5 ppb concentration, especially at the worst hole angle of 45°. The cuttings recovery from a minimum to a maximum was found to occur in this order; 45°, 60°, 30°, 90°, and 0°. In contrast with the smallest and intermediate sand grains, the largest grains have complex and less fluid transport. With a pipe orbital motion of 150 rpm and a pump rate of 42 L/min, the CTE of the muds showed higher improvement. Overall, the mud properties of the modified NC exhibited a strong enhancing impact on the cuttings carrying capacity of the base mud than the PHPA. [ABSTRACT FROM AUTHOR]

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The properties of coatings formed on the MA8 magnesium alloy by the plasma electrolytic oxidation in electrolytes containing mechanical mixture of zirconia and silica nanoparticles in concentrations of 2, 4 and 6 g/l have been investigated. It has been established by SEM, EDS, and XPS that ZrO 2 /SiO 2 nanoparticles successfully were incorporated into the coatings. Micro-Raman spectroscopy showed the presence of ZrO 2 in tetragonal and monoclinic forms in the PEO-coating composition as well as Mg 2 SiO 4 in tetrahedral configuration uniformly distributed in the outer part of coatings. Obtained coatings significantly reduce corrosion current density in comparison with bare Mg alloy and base PEO-layer (from 2.4 × 10–7 A/cm2 for base PEO layer to 0.7 × 10–7 A/cm2 for coatings with nanoparticles). It has been found that the presence of solid nanoparticles in the composition of coating has a positive effect on their hardness (this parameter was increased from 2.1 ± 0.3 GPa to 3.1 ± 0.4 GPa) and wearproof (the wear was reduced from (4.3 ± 0.4)×10–5 mm3/(N × m) to (3.5 ± 0.2)×10–5 mm3/(N × m)). [ABSTRACT FROM AUTHOR]

Osteomyelitis is an inflammatory process of bone and bone marrow that may even lead to patient death. Even though this disease is mainly caused by Gram-positive organisms, the proportion of bone infections caused by Gram-negative bacteria, such as Escherichia coli , has significantly increased in recent years. In this work, mesoporous silica nanoparticles have been employed as platform to engineer a nanomedicine able to eradicate E. coli - related bone infections. For that purpose, the nanoparticles have been loaded with moxifloxacin and further functionalized with Arabic gum and colistin (AG+CO-coated MX-loaded MSNs). The nanosystem demonstrated high affinity toward E. coli biofilm matrix, thanks to AG coating, and marked antibacterial effect because of the bactericidal effect of moxifloxacin and the disaggregating effect of colistin. AG+CO-coated MX-loaded MSNs were able to eradicate the infection developed on a trabecular bone in vitro and showed pronounced antibacterial efficacy in vivo against an osteomyelitis provoked by E. coli. Furthermore, AG+CO-coated MX-loaded MSNs were shown to be essentially non-cytotoxic with only slight effect on cell proliferation and mild hepatotoxicity, which might be attributed to the nature of both antibiotics. In view of these results, these nanoparticles may be considered as a promising treatment for bone infections caused by enterobacteria, such as E. coli , and introduce a general strategy against bone infections based on the implementation of antibiotics with different but complementary activity into a single nanocarrier. In this work, we propose a methodology to address E.coli bone infections by using moxifloxacin-loaded mesoporous silica nanoparticles coated with Arabic gum containing colistin (AG+CO-coated MX-loaded MSNs). The in vitro evaluation of this nanosystem demonstrated high affinity toward E. coli biofilm matrix thanks to the Arabic gum coating, a disaggregating and antibacterial effect of colistin, and a remarkable antibiofilm action because of the bactericidal ability of moxifloxacin and colistin. This anti- E. coli capacity of AG+CO-coated MX-loaded MSNs was brought out in an in vivo rabbit model of osteomyelitis where the nanosystem was able to eradicate more than 90% of the bacterial load within the infected bone. [Display omitted] [ABSTRACT FROM AUTHOR]

Our contributions to mesoporous silica materials in the field of biomedicine are reported in this article. This perspective article represents our work in the basics of the material, preparing different ranges of mesoporous silica nanoparticles with different diameters and with varied pore sizes. We demonstrated the high loading capacity of these materials. Additionally, the possibility of functionalizing both internal and external surface with different organic or inorganic moieties allowed the development of stimuli-responsive features which allowed a proper control on the administered dose. In addition, we have demonstrated that these carriers are not toxic, and we have also ensured that the load reaches its destination without affecting healthy tissues. This paper presents my personal opinion and background on a hot topic as mesoporous silica nanoparticles for drug delivery. To this aim it provides a comprehensive and historical overview on the innovative contributions of my research group to this rapidly expanding field of research. [Display omitted] [ABSTRACT FROM AUTHOR]

In this manuscript, we propose a simple and versatile methodology to design nanosystems based on biocompatible and multicomponent mesoporous silica nanoparticles (MSNs) for infection management. This strategy relies on the combination of antibiotic molecules and antimicrobial metal ions into the same nanosystem, affording a significant improvement of the antibiofilm effect compared to that of nanosystems carrying only one of these agents. The multicomponent nanosystem is based on MSNs externally functionalized with a polyamine dendrimer (MSN-G3) that favors internalization inside the bacteria and allows the complexation of multiactive metal ions (MSN-G3-Mn+). Importantly, the selection of both the antibiotic and the cation may be done depending on clinical needs. Herein, levofloxacin and Zn2+ ion, chosen owing to both its antimicrobial and osteogenic capability, have been incorporated. This dual biological role of Zn2+ could have and adjuvant effect thought destroying the biofilm in combination with the antibiotic as well as aid to the repair and regeneration of lost bone tissue associated to osteolysis during infection process. The versatility of the nanosystem has been demonstrated incorporating Ag+ ions in a reference nanosystem. In vitro antimicrobial assays in planktonic and biofilm state show a high antimicrobial efficacy due to the combined action of levofloxacin and Zn2+, achieving an antimicrobial efficacy above 99% compared to the MSNs containing only one of the microbicide agents. In vitro cell cultures with MC3T3-E1 preosteoblasts reveal the osteogenic capability of the nanosystem, showing a positive effect on osteoblastic differentiation while preserving the cell viability. A simple and versatile methodology to design biocompatible and multicomponent MSNs based nanosystems for infection management is proposed. These nanosystems, containing two antimicrobial agents, levofloxacin and Zn2+, have been synthetized by external functionalization of MSNs with a polycationic dendrimer (MSNs-G3), which favours its internalization inside the bacteria and lead the complexation with metal ions through the amines of the dendrimer. The nanosystems offer a notable improvement of the antibiofilm effect (above 99%) than both components separately as well as osteogenic capability with positive effect on the osteoblastic differentiation and preserved cell viability. [Display omitted] [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the delivery of poorly water-soluble non-steroidal anti-inflammatory drugs (NSAIDs) by carboxyl-functionalized mesoporous silica nanoparticles (MSN-COOH) with high specific surface area (S BET). In this study, MSN-COOH was prepared by collaborative self-assembly using cetyltrimethylammonium bromide (CTAB) as template and hydrolysis (3-triethoxyl-propyl) succinic anhydride (TESPSA) as co-structure auxiliary directing agent (CSDA). The drug delivery systems were constructed with NSAIDs including Nimesulide (NMS) and Indomethacin (IMC) as model drugs. Moreover, the characterization techniques, hemolysis and bio-adsorption testes, in vitro drug release and in vivo biological studies of MSN-COOH were also carried out. The characterization results showed that MSN-COOH is spheres with clearly visible irregular honeycomb nanopores and rough surface (S BET : 1257 m2/g, pore volume (V P): 1.17 cm3/g). After loading NMS/IMC into MSN-COOH with high drug loading efficiency (NMS: 98.7 and IMC: 98.2%), most crystalline NMS and IMC converted to amorphous phase confirmed using differential scanning calorimeter (DSC) and X-ray power diffraction (XRD) analysis. Meanwhile, MSN-COOH significantly increased the dissolution of NMS and IMC compared with non-functionalized mesoporous silica nanoparticles (MSN), which was also confirmed by wettability experiments. The results of in vivo biological effects showed that MSN-COOH had higher bioavailability of NMS and IMC than MSN, and exerted strong anti-inflammatory effects by delivering more NMS and IMC in vivo. This study successfully prepared MSNs-COOH (mesoporous silica nanoparticles modified with negatively charged carboxyl groups on the surface and in the pores) with high specific surface area and pore volume by using the negatively charged carboxyl group (hyd-TESPSA) and the positively charged CTAB self-assembled through electrostatic attraction under alkaline conditions. The drug delivery systems were constructed with Nimesulide (NMS) and Indomethacin (IMC) as model drugs. The results showed MSNs-COOH had high drug loading capacity and also exhibited good in vitro drug release properties. Interestingly, NMS loaded MSNs-COOH also had a potential pH responsive release effect. In vivo biological studies revealed that NMS/IMC loaded MSNs-COOH could evidently improve the bioavailability and played the strong anti-inflammatory effects. [Display omitted] [ABSTRACT FROM AUTHOR]

This work is a continuance to our previous findings on silica nanoparticles (NPs) modified with diamine polymer, carboxymethyl-β-cyclodextrin (CM-β-CD) and folic acid (FA), respectively. When four different polymer lengths (D230, D400, D2000 and D4000) were analyzed, the release rate of anticancer agents was inversely related to the polymer length while the cell toxicity was directly related to the length. We investigate here the effect of polymer length on the extent of cellular interaction with HeLa cells. The mean particle size, the polydispersity (PD) and the zeta potential of the NPs were measured using dynamic light scattering (DLS), the quantitative analysis of the extent of NPs' interaction was studied using fluorescence microscopy and transmission electron microscopy (TEM) was used to qualitatively visualize them. The particle size increased by increasing the polymer length, the PD values were within the acceptable ranges (0.3−0.5) and the zeta potential was in the range of (−16 to −20 mV). A direct relation was observed between the fluorescence intensity and the length. All modified NPs were capable of entering the cells, however a greater number of NPs with long polymers was observed compared to short polymers. Thus, the direct relation of polymer length to the cell toxicity is due to the release rate behavior and the enhanced interaction of NPs which possess long polymers. [ABSTRACT FROM AUTHOR]

In quasi-solid electrolytes loaded with nanoparticles such as silica and titania, the solvent of the electrolyte has a key role in the separation of ionic species and their adsorption on the surface of nanoparticle. The present article demonstrates the effect of different solvents on the ionic adsorption and its impact on the photoelectrochemical characteristics of dye sensitized solar cells (DSSCs). Ionic adsorption behaviour has been studied by zeta potential measurements and analysis of carbon to nitrogen (C/N) ratio. It has been found out that effective cationic adsorption occurs in 3-methoxypropionitrile (MPN) as solvent in electrolyte, whereas poor adsorption occurs in N-methyl-2-pyrrolidone (NMP)-based electrolyte due to the higher donor number of the latter which results in effective interaction of solvent and nanopowder. Performance of DSSC fabricated with MPN-based solvent in electrolyte was superior to others in both liquid and quasi-solid electrolytes. [ABSTRACT FROM AUTHOR]

• Fingermark press with adjustable force to provide consistent latent fingermarks. • Commercially available polystyrene microparticles to enhance latent fingermarks. • Total internal reflection (TIR) illumination of enhanced fingermarks for better contrast. • Fingermark images evaluated in terms of number of matched minutiae, image contrast, brightness. A variety of suspended silica and metal nanoparticles have been used over the last 20 years to enhance latent fingermarks. This study quantitatively evaluates enhancement of natural and sebum-enriched fingermarks from three adult subjects acquired with a consistent applied force on glass with a fingermark press using suspended commercially available polystyrene (PS) particles. Images of the enhanced fingermarks acquired with total internal reflection (TIR), or standard overhead white light (WL), illumination are compared with fingermarks enhanced with conventional methods including cyanoacrylate fuming. The different enhancement and illumination methods are quantified based on the brightness and contrast of the fingermark images, as well as the number of minutiae that can be identified and matched to those on an inked manually acquired "template" fingermark using automatic fingerprint identification system (AFIS) software. Enhanced fingermarks acquired with the press are shown to be more consistent than manually acquired fingermarks based on these metrics. The results demonstrate that TIR illumination from a large-area illuminator built in house gives enhanced fingermark images with more matched minutiae and contrast superior to that for WL illumination for all types of enhancement. "Wet-powdering" with PS particles gives fingermark images that are for the most part comparable in terms of the number of matched minutiae to fingermarks enhanced with more conventional methods, suggesting that this novel enhancement method has a performance comparable to conventional enhancement methods. Interestingly, the age of the fingermark appears to have almost no effect on this new type of enhancement; sebum-enriched fingermarks ranging in age from 12 h to 435 days appear to have statistically identical numbers of matched minutiae. [ABSTRACT FROM AUTHOR]

Rice husks (RHs) was used as a substrate for biosynthesis of high-value Silica nanoparticles (SiO 2 NPs). An isolate of Trichoderma harzianum MF780864 (T. harzianum) was isolated and identified based on the Internal Transcribed Spacers (ITS) sequences; it showed the potentiality to induce SiO 2 NPs in the process of RHs biotransformation. SiO 2 NPs were produced extracellularly and their size was of about 89 nm. SiO 2 NPs characterized by oval, rod and cubical particles by using Transmission Electron Microscope (TEM).The Fourier transform infrared spectroscopy (FTIR) confirmed the presence of various functional groups of biomolecules and capping protein, encapsulating SiO 2 NPs. Water and fish samples were collected from private fish farms in El-Sharkia Governorate, Egypt. Lead (Pb) was detected from water and fish samples at its highest concentration at about 0.088 mg/L. The adsorption capacity of Pb by SiO 2 NPs was evaluated by testing different concentrations of SiO 2 NPs viz. 1, 2, and 3 mg/L, wherein 1 mg/L revealed the highest Pb adsorption efficiency. Within laboratory trials, the results indicated that highest Pb adsorption efficiency revealed through the increasing of SiO 2 NPs concentrations until 120 h. In vivo trial that lasted for 8 weeks, Nile tilapia (Oreochromis niloticus) (29.78 ± 0.36 g body weight) supplemented with 0.088 mg/L Pb was divided into four experimental groups having three replicates (15 fish/replicate; 45 fish/group). The results showed that SiO 2 NPs supplementation through water revealed significant increase in growth and hematological parameters of O. niloticus. Moreover, enhancement of antioxidant capacity (TAC), and immune related gene expression of IL-1 β were increased in the presence of SiO 2 NPs compared with the groups of Pb exposure. Moreover, Pb residue level in fish muscles was noticeably decreased in the SiO 2 NPs treated groups. Thus, this research opens up other possibilities in the field of using SiO 2 NPs as a lead adsorbent for water bioremediation. [ABSTRACT FROM AUTHOR]