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The aim of this study is to control the release of methotrexate (MTX) from a cellulose-based molecularly imprinted polymer (MIP) film containing melanin using near-infrared (NIR) laser irradiation. Methacrylic acid (MAA) as a functional monomer for the recognition of MTX was grafted to carboxymethyl cellulose through free radical polymerisation. Templating molecule MTX was then attached via hydrogen bonding to MAA. Melanin was then added to the MIP film. The MIP film selectively recognised MTX over folic acid (with a similar structure to MTX). After 808 nm NIR laser irradiation at 0.7 W/cm2 for 10 min, the surface temperature of the MIP film rose above 60°C and the MTX release and permeation rates increased rapidly. After release of the MTX from the MIP film, more uniformly sized pores were observed than seen in the non-molecularly imprinted film. These results indicate that the MIP film is suitable for transdermal drug delivery systems. [ABSTRACT FROM AUTHOR]

The key objective for establishing a new drug delivery system is to transport therapeutic medications in the body's circulatory system and deliver them to selected therapeutic spots. In the current study, 2-aminopyridine (2AP), a bioactive molecule, was wrapped around a metal oxide framework known as the Zeolite imidazole framework (ZIF-8) for efficient drug delivery in HepG2 cells. To begin with, an in-silico technique molecular docking to access the binding capability of 2AP with EGFR target, and it exhibited a score of −7.4 kcal/mol. The morphology of the nanoparticles was examined through SEM and TEM analysis, DLS and Zeta potential exhibited the particle size, stability and further elements and functional groups present in ZIF-8 and 2AP@ZIF-8 was examined through EDX, TGA, XRD, and FTIR analysis. The drug loading capacity of ZIF-8 was examined and the drug release efficiency of ZIF-8 for the delivery of 2AP was evaluated in the phosphate-buffered saline under different pH conditions and witnessed the pH-responsive and sustained drug release. The dose-dependent and time-dependent anticancer efficacy of 2AP@ZIF-8 nanoparticles treated HepG2 cells has been investigated through the in-vitro MTT assay method. The IC50 values of 2AP@ZIF-8 nanoparticles for 24, 48, and 72 h were observed to be 54.8, 48.5, and 45.3 μg/mL, respectively. The ZIF-8 and 2AP@ZIF-8 showed nontoxic to HEK293 cells. Overall, our findings showed that ZIF-8 offers a pH-responsive release of 2AP loaded and 2AP@ZIF-8 caused cell death in HepG2 cells, suggesting novel therapeutic approaches against hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

This study aims to investigate Polylactic Acid (PLA) and Polycaprolactone (PCL) polymers for microencapsulation of hydrophilic and hydrophobic anti-glaucoma drugs using an emulsion-based solvent evaporation technique. Microparticle size was analysed using optical microscopy, while drug-polymer interactions through Dynamic-Light-Scattering (DLS) and Fourier-Transform-Infra-red/Attenuated-Total-Reflection spectroscopy (FTIR/ATR). In vitro, drug release studies were performed to investigate drug encapsulation and release profiles. Spherical microparticles, with particle size 94 ± 6.9 μm for PCL-based and 100 ± 3.74 μm for PLA-based formulation, were obtained. Drug release studies showed 100% release over about 32 days, with encapsulation efficiency (%EE) and drug loading (%w/w) reaching up to 95 and 2.84% for PLA-based and 97 and 2.91% for PCL-based microparticles, respectively. DLS studies reveal an increase in hydrodynamic radius (RH), which correlates to enhanced drug encapsulation. So, the nature of the drug and polymer significantly impacts drug encapsulation and release, with drug-polymer interactions playing a crucial role alongside experimental parameters. [ABSTRACT FROM AUTHOR]

Recent research is based on biocompatible drug delivery systems due to the need for bioavailability, route of administration, dose dumping, and first-pass metabolism. Despite its excellent mechanical strength, elasticity, and stability, polyurethane has associated risk factors such as high hydrophobic nature and long-term degradability. This review focuses on providing insight into polyurethane as a drug delivery system. The key objective of the review is to signify the importance of polyurethane in biomedical, the essential compounds to synthesize polyurethane, and the types of polyurethane. The review has highlighted polyurethane's drug loading and release capacity and its composites in various forms. The essential biological studies such as polyurethane's antibacterial, antiinflammatory, and anticancer activity were also discussed. Herein, polyurethane and its hybrid composites can be a potential material for future implantable drug delivery systems. [ABSTRACT FROM AUTHOR]

AbstractOur research described in this paper investigated the effect of Tween 20 as a nonionic surfactant on the physicochemical properties and drug release characteristics of Bakla starch. The effect of various concentrations of Tween 20 (0.5, 1 and 1.5% w/w) on various parameters of Bakla starch, including swelling behavior, solubility, moisture content, ash value, water holding capacity and the in-vitro drug release of paracetamol from its tablets, was examined. The incorporation of Tween 20 increased the swelling power, solubility, moisture content and water holding capacity, attributed to the alignment of its polar groups with the starch surface, which enhanced the hydrophilicity of the Bakla starch. The FTIR and XRD analysis suggested the formation of complexes of the starch with the Tween. A low concentration of Tween 20 enhanced the liquid penetration rate in tablets, whereas concentrations above 1% decreased it. This effect on penetration correlates with the enhanced release of paracetamol when Tween 20 is incorporated in the starch, underscoring the importance of the hydrophilic properties of a nonionic surfactant in controlling drug release. Therefore, our research focused on the impact of concentration and hydrophilicity of a nonionic surfactant and its interaction with Bakla starch on various physicochemical properties and the release rate of the paracetamol. [ABSTRACT FROM AUTHOR]

AbstractLocal anesthetics have been used for temporary loss of pain, which limits their clinical application due to the neurotoxicity and short half-lives. In this present investigation, we have developed a novel k-carrageenan/alginate (k-CN/AGT) hydrogel loaded with Ropivacaine (RVN) to achieve a sustained release system. The synthesized k-CN/AGT hydrogels were examined for structural characterization, morphology, and mechanical properties. The observed studies revealed hydrogel has a suitable porous structure (0.5 to 5 µm) and effective swelling ratio with controlled in vitro release kinetics. The in vitro biocompatibility test on human dermal fibroblast cells confirmed that hydrogel has a nontoxic nature. The anesthetic activity of k-CN/AGT-RVN hydrogels was evaluated in vivo and compared with commercial formulations. Ex vivo permeation efficiency of k-CN/AGT-RVN hydrogels surpassed that of the RVN. As a result, the study demonstrated that k-CN/AGT-RVN hydrogels have the potential to prolong the effects of local anesthesia, offering a promising avenue for effective pain management. [ABSTRACT FROM AUTHOR]

A tri-layer scaffold was fabricated according to functionally graded materials (FGM) theory from poly(glycerol sebcate)/poly(L-lactic acid) blend by the increasing polylactic acid ratio from the inner to the outer layer. Heparin and platelet-rich plasma were loaded in separate layers to achieve proper remodeling and patency. The scaffold showed a linear degradation trend. The elastic modulus was 13.8 ± 1.11 Mpa that was in the favorable range for constructing artificial vessels. The integrity of the layers was preserved due to its FGM structure. The scaffold showed full blood compatibility by minimal platelet adhesion and hemolysis due to relatively slow release of Heparin. [ABSTRACT FROM AUTHOR]

In this study, a novel bio-composite material that allow sustained release of plant derived antimicrobial compound was developed for the biomedical applications to prevent the infections caused by microorganisms resistant to commercial antimicrobials agents. With this aim, bacterial cellulose (BC)-p(HEMA) nanocomposite film that imprinted with eugenol (EU) via metal chelated monomer, MAH was prepared. Firstly, characterization studies were utilized by FTIR, SEM and BET analysis. Then antimicrobial assays, drug release studies and in vitro cytotoxicity test were performed. A significant antimicrobial effect against both Gram (+) Staphylococcus aureus and Gram (-) Escherichia coli bacteria and a yeast Candida albicans were observed even in low exposure time periods. When antimicrobial effect of EU compared with commercially used agents, both antifungal and antibacterial activity of EU were found to be higher. Then, sustained drug release studies showed that approximately 55% of EU was released up to 50 h. This result proved the achievement of the molecular imprinting for an immobilization of molecules that desired to release on an area in a long-time interval. Finally, the in vitro cytotoxicity experiment performed with the mouse L929 cell line determined that the synthesized EU-imprinted BC nanocomposite was biocompatible. [ABSTRACT FROM AUTHOR]

Molecularly imprinted polymers (MIPs) have garnered the interest of researchers in the drug delivery due to their advantages, such as exceptional durability, stability, and selectivity. In this study, a biocompatible MIP drug adsorption and delivery system with high loading capacity and controlled release, was prepared based on chitosan (CS) and graphene quantum dots (GQDs) as the matrix, and the anticancer drug oxaliplatin (OXAL) as the template. Additionally, samples without the drug (non-imprinted polymers, NIPs) were created for comparison. GQDs were produced using the hydrothermal method, and samples underwent characterization through FTIR, XRD, FESEM, and TGA. Various experiments were conducted to determine the optimal pH for drug adsorption, along with kinetic and isotherm studies, selectivity assessments, in vitro drug release and kinetic evaluations. The highest drug binding capacity was observed at pH 6.5. The results indicated the Lagergren-first-order kinetic model (with rate constant of 0.038 min−1) and the Langmuir isotherm (with maximum adsorption capacity of 17.15 mg g−1) exhibited better alignment with the experimental data. The developed MIPs displayed significant selectivity towards OXAL, by an imprinting factor of 2.88, in comparison to two similar drugs (cisplatin and carboplatin). Furthermore, the analysis of the drug release profile showed a burst release for CS-Drug (87% within 3 h) at pH 7.4, where the release from the CS-GQD-Drug did not occur at pH 7.4 and 10; instead, the release was observed at pH 1.2 in a controlled manner (100% within 28 h). Consequently, this specific OXAL adsorption and delivery system holds promise for cancer treatment. [ABSTRACT FROM AUTHOR]

Lurasidone hydrochloride (LRS HCl), an antipsychotic drug with low aqueous solubility, was dispersed in a matrix of polyethylene glycol (PEG) using the green solvent evaporation method. The green solvents used were water and ethanol. Solid dispersions and physical mixtures were prepared at various drug-to-polymer ratios, characterized by XRPD, FTIR, and DSC analyzes, and then used for the preparation of fast disintegrating tablets (FDTs). The tablets were analyzed for hardness, disintegration, and in vitro dissolution of LRS HCl. In vitro release profiles showed a significant improvement in the release rate of LRS HCl from tablets prepared with solid dispersions compared to those containing untreated LRS HCl or the physical mixture. The presented results confirm that the use of solid dispersions prepared by the green solvent evaporation method is a promising approach to enhance the in vitro dissolution of poorly soluble drugs such as LRS HCl. The applicability of mathematical models was tested to describe the release profiles of LRS HCl from FDTs. The diffusion process, following Fick's law for drug release, appears to be the predominant release mechanism for this specific drug in FDTs. [ABSTRACT FROM AUTHOR]

Here, a novel kind of composite scaffold was fabricated by loading vascular endothelial growth factor (VEGF) and gastrodin liposome (GAS-LP) into electrospun silk fibroin/graphene oxide(SF/GO)nanofibrous and silk fibroin sponge-filled, respectively. Our results demonstrated that VEGF and GAS exhibited different release patterns in vitro which VEGF showed rapid release rate in the first few days while GAS was released slowly and continuously as encapsulated in liposomes. The scaffolds realized the combination of intraneural vascularization drugs and electrical stimulation effectively, leading to enhanced growth of RSC96 cells. Furthermore, the scaffolds could protect RSC96 cells in an inflammatory environment. [ABSTRACT FROM AUTHOR]

In this study, latanoprost-loaded polyvinyl alcohol (PVA/LAT) nanofibers were developed as an ocular drug delivery system for glaucoma treatment. The nanofibers were constructed via electrospinning and crosslinked by glutaraldehyde. The characterization studies were conducted by scanning electron microscopy, Fourier Transform infrared spectroscopy, Brunauer, Emmett, and Teller analyses, water contact angle measurements, and also swelling and degradation studies. The PVA/LAT nanofibers crosslinked with 0.5% glutaraldehyde solution for 20 min had a cumulative release of 52% for 23 days. The results demonstrated that the PVA/LAT nanofibers have a usage potential as an ocular drug delivery system for glaucoma treatment. [ABSTRACT FROM AUTHOR]

Fabrication of a suitable drug delivery system forms an attractive strategy to overcome the low bioavailability of quercetin. Poly(2-hydroxyethyl methacrylate–co-N-hydroxyethyl acrylamide), P(HEMA-co-HEAA) copolymer samples, and homopolymers of 2-hydroxyethyl methacrylate (PHEMA) and N-hydroxyethyl acrylamide (PHEAA) offer potential as quercetin delivery matrices owing to their favorable properties rendered in this study. Free radical polymerization applied under cryogenic conditions produced the polymer gels. The homopolymers and copolymers are noncytotoxic, porous, soft cryogels with surfaces resistant to protein and HCT-116 cancer cell adhesion. In vitro, quercetin release studies from samples reveal swelling-controlled, zero-order drug release at pH = 7.4 and 37 °C with high cumulative release percentages ranging from 92.03% to 94.82%. The durability of the cryogels and limited quercetin release at pH = 2.0 indicate that these cryogels are promising matrices for successfully delivering quercetin to the small intestine, where its primary absorption occurs. [ABSTRACT FROM AUTHOR]

In this study, polyvinylpyrrolidone/sodium carboxymethyl cellulose (PVP/NaCMC) microspheres containing an antibiotic agent Mupirocin (MP) were prepared. The effect of polymer/polymer ratio, cross-linking time and drug/polymer (d/p) ratio was investigated on MP release. The best condition for the release of MP was found to be 79.2%. Polyhydroxy methacrylate (pHEMA) based microsphere-cryogel composite system was prepared in a disk form using microspheres with the best drug release profile. Surface and bulk structures of cryogel disks were identified with scanning electron microscopy (SEM). The best MP release was found in 82.7% of the microsphere-cryogel composite system. [ABSTRACT FROM AUTHOR]

In this study, monodisperse spherical particles were synthesized by using hexachlorocyclotriphosphazene (HCCP) and 1-(2-Aminoethyl) piperazine (AEP) by the polycondensation reaction. Then, the surfaces of the synthesized nanospheres were functionalized with gold nanoparticles. Phz-AEP nanospheres and phz-AEP@Au nanocomposite were characterized by various methods. Drug release studies for the synthesized phz-AEP and phz-AEP@Au nanospheres were performed using a ribonucleic acid (RNA) and sodium diclofenac (NaDc). As a result of the release studies, the drug release kinetics of the nanospheres were investigated. Additionally, the antibacterial and antifungal effects of the synthesized phz-AEP and phz-AEP@Au nanocomposite spheres were tested. [ABSTRACT FROM AUTHOR]

Scaffolds based on gelatin (Gel) play a crucial role in bone tissue engineering. However, the low mechanical properties, rapid biodegradation rate, insufficient osteogenic activity and lacking anti-infective properties limit their applications in bone regeneration. Herein, the incorporation of ibuprofen (IBU)-loaded zeolitic imidazolate framework-8 (ZIF-8) in a methacrylated gelatin (GelMA) matrix was proposed as a simple and effective strategy to develop the IBU-ZIF-8@GelMA scaffolds for enhanced bone regeneration capacity. Results indicated that the IBU-loaded ZIF-8 nanoparticles with tiny particle sizes were uniformly distributed in the GelMA matrix of the IBU-ZIF-8@GelMA scaffolds, and the IBU-loaded ZIF-8 growing in the scaffolds enabled the controlled and sustained releasing of Zn2+ and IBU in pH = 5.5 over a long period for efficient bone repair and long-term anti-inflammatory activity. Furthermore, the doping of the IBU-loaded ZIF-8 nanoparticles efficiently enhanced the compression performance of the GelMA scaffolds. In vitro studies indicated that the prepared scaffolds presented no cytotoxicity to MC3T3-E1 cells and the released Zn2+ during the degradation of the scaffolds promoted MC3T3-E1 cell osteogenic differentiation. Thus, the drug-loaded ZIF-8 modified 3D printed GelMA scaffolds demonstrated great potential in treating bone defects. [ABSTRACT FROM AUTHOR]

Targeted drug delivery (TDD) systems have several advantages, especially with drugs having toxic side effects such as lornoxicam (LX) which shows high hepatotoxicity and nephrotoxicity, especially with long-term use. This work represents an attempt to control magnetic microspheres encapsulating LX and magnetite nanoparticles (MNPs) for potential targeted drug delivery of LX. Superparamagnetic nanoparticles were fabricated via the co-precipitation method and together with LX were encapsulated into polycaprolactone (PCL) microspheres through an oilin-water (O/W) emulsion solvent evaporation method. The effects of changing the amount of drug, MNPs, and volume of the aqueous phase were investigated by preparing several microsphere formulations. Increasing the amount of encapsulated MNPs increased the magnetization of the microspheres without affecting the morphology. Doubling the volume of the aqueous phase resulted in a higher encapsulation efficiency and drug loading; 83.9% and 10.7%, respectively, while increasing the amount of drug had a negative effect on both drug loading and encapsulation efficiency. Drug release from the microspheres was successfully achieved and showed a biphasic nature. A system of four planar coils was then used to magnetically control the movement of a cluster of capsules in a glycerin medium, as a simulation for the targeting process. The microspheres were successfully controlled to move in a U-turn path with sharp corners demonstrating their potential for TDD applications. [ABSTRACT FROM AUTHOR]

The advancement from hydrogel (HDG) to nanogel (NAG) was a remarkable transition in the field of drug delivery (DD). This breakthrough opened a vista of feasibilities for the gel to interact at the cellular spectrum and prospects for systemic administering. The formation of NAG improved stimuli sensitivity and stability while suppressing the propensity to swelling. NAGs are fabricated with varying architectures including core-shell nanoparticulates, hollow NAG, dual walled as well as yolkish shell architectures, and exhibit high prospects as advanced drug delivery systems (DDS), which is ascribed to their inherent multifunctionalities along with stability in biologically affiliated fluids. Thus, due to their inherent nanosize, NAGs can penetrate replacement tissues, unlike bigger HDGs, while simultaneously proffering elevated drug loading capability as well as encapsulation effectiveness attributed to their inherent swelling capability. Here, a comprehensive elucidation of the synthesization, nanotechnological advancements, and broad research investigations conducted recently are presented. The functions of utilizing NAG as a successful tool in biomedicals, environmental protection, smart gadgets, cell cultures, and so on, are also elucidated. Therefore, this paper presents very recently emerging trends in drug releasing capability of polymeric nanogel nanoarchitectures, with special highlight on NAG mechanisms of drug releasing, triggering-sensitive NAGs, and elucidation of varying schemes for NAG releasing profiles. [ABSTRACT FROM AUTHOR]

Drug nanofibers play a crucial role in ameliorating therapeutic effects, reducing toxicity, and increasing the bioavailability of drugs. This study was aimed at the fabrication of isotretinoin-loaded MMT-reinforced bi-polymeric (PAN/PU) nanofibers with varying concentrations of isotretinoin. In this study, montmorillonite (MMT)-reinforced cross-linked polyacrylonitrile and pullulan nanofibers combined with varying amounts of isotretinoin were fabricated through an electrospinning approach and investigated for their drug permeation potential. PAN-PU nanofibers were successfully integrated with the isotretinoin. The incorporation of isotretinoin into the nanofibrous structure was confirmed by FTIR and XRD. TGA study indicated the stability of the fabricated nanoparticles. The SEM results showed the beaded and smooth morphology of nanofibers. Formulation with a higher drug concentration had a non-significantly (p > 0.05) higher swelling ratio. Drug-loaded polymeric nanofiber erodes at a slower rate as compared to drug-free nanofibers. The ex-vivo permeation study of nanofibers revealed that the drug was not released all at once, but rather gradually and consistently over the period of 24 h, indicating a controlled release of the drug. In addition, the drug concentration in the nanofibers affected the permeation of the drug. According to the findings, isotretinoin-loaded MMT-reinforced bi-polymeric (PAN/PU) nanofibers with varying concentrations of isotretinoin were successfully fabricated. The fabricated nanofibers (PAN/PU) showed a promising potential for controlled permeation of drugs through rabbit skin. [ABSTRACT FROM AUTHOR]

Liposomes are considered among the most versatile and advanced nanoparticle delivery systems used to target drugs to specific cells and tissues. Structurally, liposomes are sphere-like vesicles of phospholipid molecules that are surrounded by equal number of aqueous compartments. The spherical shell encapsulates an aqueous interior which contains substances such as peptides and proteins, hormones, enzymes, antibiotics, antifungal and anticancer agents. This structural property of liposomes makes it an important nano-carrier for drug delivery. Extrusion is one of the most frequently used technique for preparing monodisperse uni-lamellar liposomes as the technique is used to control vesicle size. The process involves passage of lipid suspension through polycarbonate membrane with a fixed pore size to produce vesicles with a diameter near the pore size of the membrane used in preparing them. An advantage of this technique is that there is no need to remove the organic solvent or detergent from the final preparation. This review focuses on composition of liposome formulation with special emphasis on factors affecting drug release and drug-loading. [ABSTRACT FROM AUTHOR]

DC Beads and CalliSpheres are commonly used microspheres in clinical transcatheter arterial chemoembolization, but these microspheres cannot be visualized by themselves. Therefore, in our previous study, we developed multimodal imaging nano-assembled microspheres (NAMs), which are visualized under CT/MR and the location of embolic microspheres can be determined during postoperative review, facilitating the evaluation of embolic areas and guiding subsequent treatment. Moreover, the NAMs can be carried with positively and negatively charged drugs, increasing the choice of drugs. Systematic comparative analysis of the pharmacokinetics of NAMs with commercially available DC Bead and CalliSpheres microspheres is important for evaluating the clinical application of NAMs. In our study, we compared the similarities and differences between NAMs and two drug-eluting beads (DEBs) in respect to drug loading capacity, drug release profiles, diameter variation and morphological characteristics. The results indicate that NAMs had good drug delivery and release characteristics as well as DC Bead and CalliSpheres in vitro experimental stage. Therefore, NAMs have a good application prospect in transcatheter arterial chemoembolization treatment of hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

In this study, PVA/p(HEMA-co-MAPTAC) hydrogels were synthesized by redox polymerization using polyvinyl alcohol (PVA), 2-hydroxyethyl methacrylate (HEMA) and [3-(Methacryloylamino)propyl]trimethylammonium chloride (MAPTAC). In order to increase the antimicrobial activities of synthesized PVA/p(HEMA-co-MAPTAC) hydrogels, they were modified with Au nanoparticles. The swelling behavior of the synthesized hydrogels was investigated. Hydrogels were characterized by various techniques. The drug release studies of PVA/p(HEMA-co-MAPTAC) and PVA/p(HEMA-co-MAPTAC)@Au hydrogels were performed in PBS medium using Ribonucleic acid (RNA) as genetic material and sodium diclofenac (NaDc) as drug. It was determined that PVA/p(HEMA-co-MAPTAC) hydrogel held 91.5 mg/g RNA and 97.48 mg/g NaDc and released 28.32 mg/g RNA and 71.12 mg/g NaDc in PBS medium. Subsequently, PVA/p(HEMA-co-MAPTAC)@Au hydrogel adsorbed 87.46 mg/g RNA and 119.44 mg/g NaDc and released 18.96 mg/g RNA, 104.99 mg/g NaDc drug in PBS medium. Using the data obtained at the end of the release studies, the drug release kinetics of the hydrogels were examined. According to the Korsmeyer Peppas model, RNA release from hydrogels showed Fickian diffusion, while NaDc release showed non-Fickian diffusion behavior. The antibacterial and antifungal activities of the hydrogels were tested using gram-negative bacteria E. coli, gram-positive bacteria B. subtilis and a fungus species C. albicans. [ABSTRACT FROM AUTHOR]

A series of mussel-inspired pH-responsive self-healing hydrogels based on gelatin crosslinked by oxidized tannic acid (GLT-OTAs) were prepared and used as controlled drug delivery systems (CDDS). An antiphlogistic drug, indomethacin (IDMC) was used as model drug to be immobilized into the hydrogels. The obtained hydrogel samples were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Mechanical stability, biocompatibility and self-healing property of the hydrogels were estimated, respectively. Swelling and drug release behaviors of these hydrogels were measured in phosphate buffered saline (PBS) with pH 7.4 (simulated intestinal fluid) and HCl solution with pH 1.2 (simulated gastric fluid) at 37 °C. Effect of the OTA content on the structures and characteristics of all samples was discussed. FTIR spectra revealed the covalent cross-linking between gelatin and OTA induced by Michael addition and Schiff base reaction. Both XRD and FTIR all showed the drug (IDMC) was loaded successfully and existed steadily. GLT-OTA hydrogels had satisfactory biocompatibility, superior self-healing. Results also illustrated that the mechanical strength, internal structure, the swelling and drug release behaviors of the GLT-OTAs hydrogel were greatly affected by the OTA content. With increasing the OTA content, the mechanical stability of GLT-OTAs hydrogel became better and better, and their internal structure became more and more compact. The swelling degree (SD) and cumulative drug release of all hydrogel samples tended to decrease with increasing OTA content and both had obvious pH responsiveness. For each hydrogel sample, the cumulative drug release in PBS at pH 7.4 was greater than that in HCl solution at pH 1.2. These results indicated that the obtained GLT-OTAs hydrogel had promising potential to be used as effective pH-responsive and self-healing drug delivery materials. [ABSTRACT FROM AUTHOR]

A series of silk fibroin composite membranes were prepared by blending silk fibroin (SF) with sodium alginate (SA) at different ratios. Different contents of polyethylene glycol (PEG) were used as a crosslinking agent to fix the structure of the composite membrane. Water-soluble pazufloxacin mesylate as the model drug was embedded in the composite membrane. The relationship between structure and properties was demonstrated by the sustained-release effect on model drug, and the experimental results revealed that the silk fibroin composite membrane had an excellent function of controlling the release behavior of model drugs, which exhibited pH responsivity to some extent. [ABSTRACT FROM AUTHOR]

Lung cancer ranks second position among the cancer-related deaths. Osimertinib mesylate (OSM) is a tyrosine-kinase-inhibitor which can effectively treat non-small cell lung cancer (NSCLC), but still there are certain limitations and side effects which could be circumvented by polymeric nanoparticles approach. Hence, this research was aimed to develop drug-loaded biodegradable polycaprolactone nanoparticles (PCL-NPs) such as OSM-loaded PCL-NPs (PCL-OSM-NPs) and chitosan fabricated OSM-loaded PCL-NPs (CS-PCL-OSM-NPs) to achieve active-targeting of OSM in the cancerous lung tissue. Thus, CS-PCL-OSM-NPs enhance the anticancer efficacy due to active targeting nature and thereby reduces off-target side effects of OSM in the NSCLC treatment. Blank PCL-NPs, PCL-OSM-NPs, and CS-PCL-OSM-NPs were prepared by nanoprecipitation method. Optimized blank PCL-NPs, PCL-OSM-NPs, and CS-PCL-OSM-NPs exhibited the mean particle size of 90.2 ± 4.7 nm, 167.7 ± 2.9 nm, and 233.7 ± 4.8 nm respectively. The encapsulation efficiency % (%EE) of PCL-OSM-NPs was found to be 68.4 ± 3.2%. In vitro drug release study demonstrated sustained release profile of 69.5 ± 5% and 65.7 ± 1.5% for OSM from both the PCL-OSM-NPs and CS-PCL-OSM-NPs, respectively. The PCL-OSM-NPs and CS-PCL-OSM-NPs demonstrated the inhibition of 82.2 ± 0.5% and 81.9 ± 0.2% in A549 cancer cells respectively which clearly signified the improved efficacy. Moreover, the PCL-OSM-NPs and CS-PCL-OSM-NPs exhibited significantly less hemolysis than OSM indicating safety of the formulation. These findings indicate that biohemocompatible CS-PCL-OSM-NPs is an attractive option to treat NSCLC with enhanced anticancer activity and reduced side effects. [ABSTRACT FROM AUTHOR]

This study aimed to improve the use of YF8, a matrine derivative obtained through chemical transformation of matrine extracted from Sophora alopecuroides. YF8 has demonstrated improved cytotoxicity compared to matrine, but its hydrophobic nature hinders its application. To overcome this, the lipid prodrug YF8-OA was synthesized by linking oleic acid (OA) to YF8 through an ester bond. Although YF8-OA could self-assemble into unique nanostructures in water, it was not sufficiently stable. To enhance the stability of YF8-OA lipid prodrug nanoparticles (LPs), we employed the strategy of PEGylation using DSPE-mPEG2000 or DSPE-mPEG2000 conjugated with folic acid (FA). This resulted in the formation of uniform spherical nanoparticles with greatly improved stability and a maximum drug load capacity upto 58.63%. Cytotoxicity was evaluated in A549, HeLa, and HepG2 cell lines. The results showed that in HeLa cells, the IC50 value of YF8-OA/LPs with FA-modified PEGylation was significantly lower than that of YF8-OA/LPs modified by PEGylation alone. However, no significant enhancement was observed in A549 and HepG2 cells. In conclusion, the lipid prodrug YF8-OA can form nanoparticles in aqueous solution to address its poor water solubility. Modification with FA resulted in further enhanced cytotoxicity, providing a potential avenue for exerting the antitumor activity of matrine analogs. [ABSTRACT FROM AUTHOR]

Nanofibers, loaded with different pharmaceutical agents, are being used extensively as advanced wound care dressings. Silver sulfadiazine is generally used for infection prevention in various burn wounds among these antimicrobial agents. The present study develops silver sulfadiazine within biopolymeric nanofibers using the post-treatment method. Sodium alginate (SA) and polyvinyl alcohol were selected due to their biocompatibility. Box-Behnken statistical technique optimized composite PVA/SA nanofibers loaded with a silver salt. The results revealed that smooth and defect-free fibers were produced by decreasing the concentration of silver salt. Composite PVA/SA/Ag nanofibers were post-treatment with 1% sodium sulfadiazine (NaSD) and calcium chloride solution. NaSD was converted into silver sulfadiazine (SSD) within the nanofibers due to ion exchange. Developed nanofibers showed good antibacterial activity against Staphylococcus aureus. In-vitro drug release study showed initial quick-release followed by a controlled release for 72 h, making it suitable for wound care applications. [ABSTRACT FROM AUTHOR]

The synthesis, characterization and modification of mesoporous silica (MS) were carried out and, drug removal and release studies were also performed. The synthesized MS has an ordered structure with high surface area and homogeneous pore size distribution, which was then modified with a Schiff base (S) ligand. The characterization of MS and Schiff base modified MS (S-MS) was accomplished with scanning electron microscopy (SEM), nitrogen gas adsorption, Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and dynamic light scattering (DLS) analyses. The adsorption of diclofenac sodium (DS) and metformin HCl (MF), which were preferred as model drugs, onto MS and S-MS, was investigated in an aqueous solution with respect to pH, the amount of adsorbent and contact time. The maximum calculated values from the pseudo-second-order model for the adsorption of MF and DS were determined as 625.5 and 675.0 mg g‒1 for MS and 558.5 and 765.7 mg g‒1 for S-MS, respectively. In addition, the hybrid structures of MS and S-MS were prepared for use in the drug release studies, and their efficiencies in releasing drugs were then investigated. The releases of DS and MF from silica hybrid structures after 4 h were determined to be at around 30% and 70%, respectively. [ABSTRACT FROM AUTHOR]

The aim was to develop a nanoscale drug delivery system with enzyme responsive and acid sensitive particle size and intelligent degradation aiming to research the inhibitory effect on breast cancer. The delivery system addressed the problems of tissue targeting, cellular internalization, and slow drug release at the target site, which could improve the efficiency of drug delivery and provide a feasible therapeutic approach for breast cancer. The acid sensitive functional material DSPE-PEG2000-dyn-PEG-R9 was synthesized by Michael addition reaction. Then, the berberine plus baicalin intelligent micelles were prepared by thin-film hydration. Subsequently, we characterized the physical and chemical properties of berberine plus baicalin intelligent micelles, evaluated its anti-tumor effects in vivo and in vitro. The target molecule was successfully synthesized, and the intelligent micelles showed excellent chemical and physical properties, delayed drug release and high encapsulation efficiency. In vitro and in vivo experiments also confirmed that the intelligent micelles could effectively target tumor sites, penetrate tumor tissues, enrich in tumor cells, inhibit tumor cell proliferation, inhibit tumor cell invasion and migration, and induce tumor cell apoptosis. Berberine plus baicalin intelligent micelles have excellent anti-tumor effects and no toxicity to normal tissues, which provides a new potential drug delivery strategy for the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

In the present study, a novel thermo-responsive microgel with aggregation induced emission (AIE) based on hyperbranched polysiloxane (HBPS) as the AIE-active luminogen, its thermo-responsiveness and application in controlled release of drug is firstly reported. Firstly, HBPS was prepared by transesterification, and then it was copolymerized with N-isopropylacrylamide (NIPAm) to prepare microgel of hyperbranched polysiloxane/poly(N-isopropylacrylamide) (HBPS@PNIPAm) by free radical copolymerization. The microstructure of the as-prepared microgel was characterized, and its behavior of drug loading and release was researched by PL with Luteolin as model drug. The results showed that the microgel had the thermo-response enhanced by AIE-active fluorescence with increasing temperature, its fluorescence emission could be adjusted by environmental temperature, or content of Luteolin loaded in the microgel, and the drug loading or release properties of Luteolin could be detected easily by fluorescence spectrum of microgel. [ABSTRACT FROM AUTHOR]

The use of magnetic carbon nanotubes for multi-modal cancer treatment, incorporating both hyperthermia and drug delivery functions, has drawn substantial interest. Yet, the present method of regulating hyperthermia temperature involves manually adjusting the magnetic field intensity, adding to the complexity and difficulty of clinical applications. This study seeks to design novel magnetic carbon nanotubes capable of self-temperature regulation, and investigate their drug loading and release characteristics. Using the co-precipitation method, we synthesized magnetic carbon nanotubes with a Curie temperature of 43 °C. A comprehensive investigation was conducted to analyze their morphology, crystal structure, and magnetic characteristics. To enhance their functionality, chitosan and sodium alginate modifications were introduced, enabling the loading of the antitumor drug doxorubicin hydrochloride (DOX) into these magnetic carbon nanotubes. Subsequently, the loading and release properties of DOX were investigated within the modified magnetic nanotubes. Under alternating magnetic field, magnetic carbon nanotubes exhibit self-regulating properties by undergoing a magnetic phase transition, maintaining temperatures around 43 °C as required for hyperthermia. On the other hand, during magnetic induction heating, the release percentage of DOX reached 23.5% within 2 h and 71.7% within 70 h at tumor pH conditions, indicating their potential for sustained drug release. The prepared magnetic carbon nanotubes can effectively regulate the temperature during hyperthermia treatment while ensuring controlled drug release, which presents a promising method for preparing nanomaterials that synergistically enhance magnetic hyperthermia and chemotherapy drugs. [ABSTRACT FROM AUTHOR]

The design of drug nanocarriers is a topic of current interest. To achieve a desirable efficiency, the preparation of a new nanocarrier must tune multiple complicated factors. Polyethylene glycol (PEG) has demonstrated the ability to evade biological barriers of living matter. In this work, the synthesis of nanocomposites prepared with PEG and carbon nanotubes (CNTs) functionalized with amine ending groups (named CNTsamine), which could be used as nanocarriers is described. A thorough characterization of prepared nanocomposites using Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) is presented. To explore the possibility of using the PEG/CNTsamine nanocomposites as suitable carriers its toxicity to HeLa cells was evaluated, their ability to release the anti-cancer drug cisplatin was determined, and their capacity to inhibit the growth of bacteria Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli as well as the fungus Candida albicans was studied. Although the PEG/CNTsamine nanocomposites have the ability to release the drug cisplatin with better efficacy than pure PEG, the evidence that produces a toxic effect on HeLa cells limit their practical use as suitable nanocarriers. [ABSTRACT FROM AUTHOR]

This paper studies a parabolic-type system of time-dependent partial differential equations coupled with Robin boundary conditions to model the solvent penetration and subsequently a controlled drug release from a swellable polymeric spherical platform. The model's key feature is that the solvent penetration and the polymer swelling result in moving boundaries. From an analytical perspective, some properties of the solutions, such as the positivity and the uniqueness of the solutions, are established. A second-order iterative procedure based on the backward finite difference method is carried out to solve the problem numerically. Finally, the numerical results and the asymptotic solutions are compared, intending to illustrate the validity and applicability of the numerical scheme. [ABSTRACT FROM AUTHOR]

Traditional drug solutions or suspensions, have been shown to treat pain in complete Freund's adjuvant (CFA)-induced chronic inflammatory pain in rats, with or without combination with magnetic therapy. In this study, we aimed to prepare, characterize, and evaluate the therapeutic effects of microparticles containing dexamethasone for local administration and treatment of chronic inflammatory pain. The results showed the following; a) Preparation and characterization: two ratios of poly(lactic-co-glycolic acid) (PLGA)/poly(lactic acid) (PLA) were used. The prepared batches were similar in size and magnetic responsiveness. The microparticle size distribution assessed via electron microscopy suggested a homogeneous distribution and absence of aggregates. Dexamethasone release profiles (microparticles synthesized with a feed ratio of 1:4) showed a sustained release in vitro and good biocompatibility with tissues. b) Therapeutic effect: the treatment effect of dexamethasone-PLGA magnetic microspheres + magnetic therapy was substantially better than that observed for other groups on day 4, as monitored by appearance, mechanical pain threshold, and histological analysis. This type of carrier could be a suitable magnetically retainable local drug delivery system for treating chronic pain. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is a worldwide disease posing serious threats to people's life. Surgery and postsurgical chemotherapy are still the first choices to control the rapid progression of cancer. However, tumor recurrence and even distant metastasis are prone to occur. As a result, it is in urgent demand to find a new method to control CRC progression while inhibiting distant metastasis. On this basis, this study developed the three-layered functionalized hydrogel-fibrous membrane-hydrogel composite materials. The Chinese traditional drugs 20 (S)-ginsenoside Rg3 (Rg3) and chemotherapeutic agent 5-fluorouracil (5-Fu) were loaded in the inner hydrogel and middle fibrous membrane and could be constantly released at the same time and space. The outer hydrogel was decorated with phenylboronic acid (PA) to interact with sialic acid expressed on the CRC cell surface. The composite materials possessed biocompatibility and showed no toxicity to normal human intestinal mucosa endothelial cells HIEC. According to the results, the cell viability of CT26 could be significantly decreased in vitro. The three-layered functionalized materials inhibited the original tumor progression and distant tumor metastasis to the liver in an orthotopic colon cancer mouse model by increasing the caspase3 expression and inhibiting the expressions of Bcl-2, Ki-67, and VEGF. In addition, the functions of major organs were not significantly damaged. Our study provides a safe and efficacious method of this three-layered functionalized hydrogel-fibrous membrane-hydrogel composite materials for CRC treatment. [ABSTRACT FROM AUTHOR]

Promising active pharmaceutical ingredients (APIs) often exhibit poor aqueous solubility and thus a low bioavailability that substantially limits their pharmaceutical application. Hence, efficient formulations are required for an effective translation into highly efficient drug products. One strategy is the preservation of an amorphous state of the API within a carrier matrix, which leads to enhanced dissolution. In this work, mesoporous silica aerogels (SA) were utilized as a carrier matrix for the amorphization of the poorly water-soluble model drug ibuprofen. Loading of tailored SA was performed post-synthetically and solvent-free, either by co-milling or via the melting method. Thorough analyses of these processes demonstrated the influence of macrostructural changes during the drying and grinding process on the microstructural properties of the SA. Furthermore, interfacial SA-drug interaction properties were selectively tuned by attaching terminal hydrophilic amino-or hydrophobic methyl groups to the surface of the gel. We demonstrate that not only the chemical surface properties of the SA, but also formulation-related parameters, such as the carrier-to-drug ratio, as well as process-related parameters, such as the drug loading method, decisively influence the ibuprofen adsorption efficiency. In addition, the drug-loaded SA formulations exhibited a remarkable physical stability over a period of 6 months. Furthermore, the release behavior is shown to change considerably with different surface properties of the SA matrix. Hence, the reported results demonstrate that utilizing specifically processed and modified SA offers a compelling technique for enhancement of the bioavailability of poorly-water soluble APIs and a versatile adjustment of their release profile. [ABSTRACT FROM AUTHOR]

This study was designed to evaluate paraffin wax as a potential controlled release matrix for spray congealing and its impact on drug release and stability of the microparticles. Paraffin wax can form a hydrophobic barrier to moisture and reduce drug degradation besides retarding drug release in the gastrointestinal tract. More hydrophilic lipid-based additives can be incorporated to modulate the drug release through the paraffin wax barrier. This study reports the findings of lipid–wax formulations at preserving the stability of moisture-sensitive drugs in spray-congealed microparticles. Aspirin-loaded microparticles formulated with different drug loads, lipid additives, and lipid:wax ratios were produced by spray congealing. Stearic acid (SA), cetyl alcohol (CA), and cetyl ester (CE) were the lipid additives studied. The microparticles were evaluated for yield, encapsulation efficiency, particle size, drug stability, and release. CE exhibited the greatest effect on increasing drug release, followed by CA and SA. Dissolution profiles showed the best fit to Weibull kinetic model. The degree of drug degradation was low, with CA imparting the least protective effect, followed by SA and CE. Paraffin wax is useful for preserving the stability of moisture-sensitive aspirin and retarding its release from spray-congealed microparticles. The addition of lipid additives modulated drug release without compromising drug stability. [ABSTRACT FROM AUTHOR]

The use of hydrogel-based contact lens materials holds promise for ophthalmic drug delivery by increasing drug residence time, improving drug bioavailability, reducing administration frequency, and enhancing special site targeting. Issues such as ease of manufacturing, lens comfort and appropriate release kinetics must be considered. Furthermore, the high water content of hydrogel materials can result in rapid and poorly controlled release kinetics. Herein, we modified common hydrogels used in contact lens manufacturing with phenylboronic acid (PBA). PBA addresses these material design issues since boronate esters are easily formed when boron acid and diols interact, opening up a pathway for simple modification of the model lens materials with saccharide based wetting agents. The wetting agents have the potential to improve lens comfort. Furthermore, the hydrophobicity of PBA and the presence of diols can be useful to help control drug release kinetics. In this work, polymerizable 3-(acrylamido)phenylboronic acid (APBA) was synthesized and incorporated into various hydrogels used in contact lens applications, including poly(2-hydroxyethylmethacrylate) (PHEMA), polyvinylpyrrolidone (PVP) and poly(N,N-dimethyl acrylamide) (PDMA) using UV induced free radical polymerization. The APBA structure and its incorporation into the hydrogel materials were confirmed by NMR and FTIR. The materials were shown to interact with and bind wetting agents such as hyaluronan (HA) and hydroxypropyl guar (HPG) by simple soaking in an aqueous solution. The equilibrium water content of the modified materials was characterized, demonstrating that most materials are still in the appropriate range after the introduction of the hydrophobic PBA. The release of three model ophthalmic drugs with varying hydrophilicity, atropine, atropine sulfate and dexamethasone, was examined. The presence of PBA in the materials was found to promote sustained drug release due to its hydrophobic nature. The results suggest that the modification of the materials with PBA was able to not only provide a mucoadhesive property that enhanced wetting agent interactions with the materials, but had the potential to alter drug release. Thus, the modification of contact lens materials with mucoadhesive functionality may be useful in the design of hydrogel contact lenses for ophthalmic drug release and wetting agent binding. [ABSTRACT FROM AUTHOR]

In this study, methacrylic acid-based containing both anionic and cationic groups in its structure p(Methacrylic acid-co-(3-acrylamidopropyl)trimethylammonium chloride) (p(MAA-co-APTMACl)) and p(Methacrylic acid-co-(2-(acryloyloxy)ethyl)trimethylammonium chloride) (p(MAA-AETAC)) hydrogels were synthesized by redox polymerization technique. The morphology, chemical structure and thermal properties of the synthesized hydrogels were characterized by SEM, FT-IR, and TGA. The swelling characterizations of the synthesized MAA-based hydrogels were carried out in various biological environments. Usability of amphoteric hydrogels containing anionic and cationic groups in their structures as a drug carrier cargo material were investigated for the treatment of two different diseases. For this, two of the selected model drugs were loaded simultaneously on hydrogels and their release properties were examined. The drug release mechanisms were investigated according to the Korsmeyer–Peppas model. Rhodamin 6G and ceftriaxone sodium were loaded to p(MAA-co-APTMACl) hydrogel for dual drug release. In addition, Rhodamin 6G and sulfadiazine were loaded simultaneously on the p(MAA-co-AETAC) hydrogel. According to the release mechanism results obtained for p(MAA-co-AETAC) hydrogels, it was determined that it showed a super-state diffusion mechanism. In addition, antibacterial activities of p(MAA-co-APTMACl) and p(MAA-co-AETAC) hydrogels against gram-negative bacteria (Escherichia coli and Pseudomonas Aeruginosa) and gram-positive bacteria (Staphylococcus Aureus and Bacillus Subtilis) were investigated. [ABSTRACT FROM AUTHOR]

In this study we have developed a cisplatin drug carrier nanoparticles based on biomaterials—chitosan and lactic acid. Drug was loaded in synthesized Chitosan-co-lactic acid nanoparticles by absorption method, to investigate the drug release behavior. Nanoparticles have potential to encapsulate drug and subsequent release it in swelling controlled manner. The release profile of cisplatin from nanoparticles showed controlled release for over 3 days. It has also been observed that the drug release is highly influenced by the chemical composition, pH, temperature and physiological fluids. Several drug release model have been used to design an effective formulation and to provide the understanding of drug release profile from a therapeutic system. These nanoparticles of chitosan-co-lactic acid have been found to be promising biomaterials as controlled drug release vehicles. [ABSTRACT FROM AUTHOR]

Although amorphous calcium phosphate has been a mature research object in the medicine field, its application in drug carriers remains restricted due to its easy agglomeration and poor dispersion stability. Accordingly, the ACP was modified with hyaluronic acid (HA) and hexametaphosphate ((NaPO3)6), the amorphous structure can be kept for more than 3 months based on HA stabilizers, the dispersion can be maintained for about one month owing to the (NaPO3)6. In vitro, the Cur-HA-ACP-(NaPO3)6 nanoparticles showed high drug loading, good pH response performance and favorable antitumor ability. Overall, Cur loaded HA-ACP nanoparticles exhibited a great potential for anticancer chemotherapeutics. [ABSTRACT FROM AUTHOR]

Progress in the drug delivery system in the last few decades has led to many advancements for efficient drug delivery. Both micro and nanorobots, are regarded as superior drug delivery systems to deliver drugs efficiently by altering other forms of energy into propulsion and movements. Furthermore, it can be advantageous as it is directed to targeted sites beneath physiological environments and conditions. They have been validated to possess the capability to encapsulate, transport, and supply therapeutic contents directly to the disease sites, thus enhancing the therapeutic efficiency and decreasing systemic side effects of the toxic drugs. This review discusses about the microand nanorobots for the diagnostics and management of diseases, types of micro, and nanorobots, role of robots in drug delivery, and its biomedical applications. [ABSTRACT FROM AUTHOR]

In view of non-immunogenic containers of biomolecules, we investigated zigzag (8, 0) single-walled carbon nanotube (SWCNT) as a vehicle for the selectivity delivery of Bendamustine hydrochloride (Benda-HCl) drug to the cell target in silico using the density functional theory (DFT) approach. During drug interaction with the carbon nanotube surface, at about 56 kJ/mol of energy is liberated in the most stable structure of the Benda-HCl@SWCNT complex. Therefore, there is an attractive van der Waals (vdW) interaction between the drug molecule and SWCNT during the exothermic adsorption. The kinetic and thermodynamic stability of the Benda-HCl@SWCNT complex is evaluated with the reactivity descriptors such as individual energy change of donor (ΔEB(A)), the fractional number of electrons (ΔN), the overall stabilisation energy (ΔESE) and the individual energy change of acceptor (ΔEA(B)). The analysis of the electronic properties shows that no sensible charge transfer occurs between the nanotube and the drug molecule due to the physisorption process. Furthermore, the binding affinity of the drug molecule to SWCNT is decreased in an acidic environment. The findings of the present research work suggest that carbon nanotube can be effectively utilised as a Bendamustine hydrochloride drug delivery vehicle. Abbreviations: Benda-HCl: bendamustine hydrochloride; BSSE: basis set superposition error; DFT: density functional theory; Einter: interaction energy; HOMO: the highest occupied molecular orbital; LUMO: the lowest unoccupied molecular orbital; NBO: natural bond orbital analysis; PDOS: projected density of state; TDOS: total density of states [ABSTRACT FROM AUTHOR]

The bilayer nanofibrous membrane fabricated via electrospinning technique can be considered as an ideal structure for the treatment of chronic skin diseases and exudative wound dressings. Wound exudate would affect healing and increases the likelihood of infection at the same time. Therefore, it is essential to produce a kind of wound dressing with relatively high hygroscopicity which could absorb wound exudate and provide a relatively dry healing environment. Bilayer nanofibrous membranes of poly(L-lactide-co-ε-caprolactone)/tetracycline hydrochloride- polyethylene oxide/sodium alginate-zinc oxide (PLCL/TCH-PEO/SA-ZnO) with drug delivery potential were prepared by electrospinning for wound healing. Then, a cross-linking which involved soaking the samples in an aqueous solution containing strontium ions for 4 h was conducted. SEM images showed that membranes still maintained the peculiar nanofibrous structure. The spinning aid (PEO) used was removed in the cross-linked alginate without affecting the PLCL/TCH outer layer gave the membrane good mechanical properties and manageability. The hydrophilicity of the mats was tested to evaluate the ability of the bilayer membrane to absorb exudate from the wound. In vitro drug release suggested that antibacterial agents TCH could release continuously more than 10 days. The cross-linked fibrous membrane has improved mechanical properties and fluid repellency, thus representing a barrier to the external environment and effective wound protection. Consequently, the bilayer fibrous scaffold with good hygroscopicity and drug release properties would have wide applications prospects for the treatment of chronic skin diseases and exudative wound dressings. [ABSTRACT FROM AUTHOR]

Dual-responsive nanocapsules of poly (N-isopropyl acrylamide (NIPAM)-co-acrylic acid (AA)-co-2-hydroxyethylmethacrylate (HEMA)) were synthesized by precipitation polymerization. The dual (temperature- and pH-)-responsive nanocapsules were fabricated using NIPAM as a temperature-sensitive monomer, AA as a pH-responsive monomer and 5-fluorouracil (5-FU) as a model drug. The P(NIPAM-co-AA-co-HEMA) nanocarrier had a hollow nanocapsule structure with average diameter of about 70 nm and a shell thickness of about 10 nm. The nanocarrier exhibited good loading capacity (32.6%) and considerable encapsulation efficiency (57.3%) for 5-FU by physical entrapment. The zeta potentials of nanocapsules were observed from −30.7 to −35.2 mV after the incorporation of 5-FU. The cumulative release of nanocapsules reached at 88.7% (37 °C, pH 5.8). The overall drug release performance revealed that the drug release behavior was efficient, sustainable and stable at 37 °C and pH 7.4. In addition, the release mechanism analysis suggested that the drug release behavior is more dependent on pH than temperature. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (MNPs) with safety, stability and excellent magneto-calorific effect are the precondition for the smart magnetic drug carriers' fabrication and controllable drug release at a specific target in clinical treatment. In this study, the drug release and magneto-calorific effect of two types of magnetic lipid microcapsules (MLMs) loading lipid-coated MNPs and uncoated MNPs respectively were compared deeply in experimental analysis and theoretical simulation. The simulation results revealed that almost same magnetic heat effect and temperature increasing exist between lipid-coated and uncoated MNPs, which was consistent with the experimental drug release results. Coating lipid on MNPs didn't affect the magnetic heat and heat transfer of the MNPs. Because of the heat transfer between MNPs and water, MLMs and water around, the temperature increasing of whole sample solution is lower than that of the MNPs themselves. Our results provide a reliable theoretical basis for the development of healthy, safe, and biocompatible drug delivery systems. [ABSTRACT FROM AUTHOR]

As a multi-target drug to treat ischemic stroke, N-butylphthalide (NBP) is extremely water-insoluble and exhibits limited oral bioavailability, impeding its wide oral application. Effective treatment of ischemic stroke by NBP requires timely and efficient drug exposure, necessitating the development of new oral formulations. Herein, liposomes containing biosurfactant sodium cholate (CA-liposomes) were systemically investigated as an oral NBP delivery platform because of its high biocompatibility and great potential for clinical applications. The optimized liposomes have a uniform hydrodynamic size of 104.30 ± 1.60nm and excellent encapsulation efficiency (93.91 ± 1.10%). Intriguingly, NBP-loaded CA-liposomes produced rapid drug release and the cumulative release was up to 88.09 ± 4.04% during 12 h while that for NBP group was only 6.79 ± 0.99%. Caco-2 cell monolayer assay demonstrated the superior cell uptake and transport efficiency of NBP-loaded CA-liposomes than free NBP, which was mediated by passive diffusion via transcellular and paracellular routes. After oral administration to rats, NBP-loaded CA-liposomes exhibited rapid and almost complete drug absorption, with a tmax of 0.70 ± 0.14 h and an absolute bioavailability of 92.65% while NBP suspension demonstrated relatively low bioavailability (21.7%). Meanwhile, NBP-loaded CA-liposomes produced 18.30-fold drug concentration in the brain at 5 min compared with NBP suspension, and the brain bioavailability increased by 2.48-fold. As expected, NBP-loaded CA-liposomes demonstrated significant therapeutic efficacy in a middle cerebral artery occlusion rat model. Our study provides new insights for engineering oral formulations of NBP with fast and sufficient drug exposure against ischemic stroke in the clinic. [ABSTRACT FROM AUTHOR]

Minocycline hydrochloride (MINO) has been one of the most frequently used antibiotics in the treatment of periodontitis due to its antibacterial activity and osteogenesis effects; however, high levels of MINO administered during the treatment halt the formation of new bone. Therefore, the purpose of the present study was to prepare a MINO-microsphere/sucrose acetate isobutyrate (SAIB) hybrid depot to reduce the burst release of MINO and ensure antibacterial and osteogenesis effects of MINO in the treatment of periodontitis. Uniform microspheres, approximately 5 mm size, with a slightly rough surface and different MINO loading (10, 12, and 14%) were prepared, and the microspheres were added into SAIB, after which the burst release significantly decreased from 66.18 to 2.92%, from 71.82 to 3.82%, and from 73.35 to 4.45%, respectively, and the release from all the MINO-microspheres/SAIB hybrid depots lasted for 77 days. In addition, cytotoxicity test showed that the MINO-microsphere with 12% drug loading promoted the proliferation of osteoblasts the most and was subsequently used in vivo experiments. Moreover, in the model of ligatured-induced periodontitis in SD rats, the MINOmicrosphere/SAIB hybrid depot not only significantly increased the alveolar bone height and bone volume but also reduced the inflammation of the periodontal tissue. Additionally, it also inhibited the expression of the receptor activator of nuclear factor-kappa B ligand (RANKL) and promoted the expression of osteoprotegerin (OPG). These results indicated that the MINO-microsphere/SAIB hybrid depot might be promising in the treatment of periodontitis. [ABSTRACT FROM AUTHOR]

Controlled drug delivery systems are of utmost importance for the improvement of drug bioavailability while limiting the side effects. For the improvement of their performances, drug release modeling is a significant tool for the further optimization of the drug delivery systems to cross the barrier to practical application. We report here on the modeling of the diclofenac sodium salt (DCF) release from a hydrogel matrix based on PEGylated chitosan in the context of Multifractal Theory of Motion, by means of a fundamental spinor set given by 2-2 matrices with real elements, which can describe the drug-release dynamics at global and local scales. The drug delivery systems were prepared by in situ hydrogenation of PEGylated chitosan with citral in the presence of the DCF, by varying the hydrophilic/hydrophobic ratio of the components. They demonstrated a good dispersion of the drug into the matrix by forming matrix-drug entities which enabled a prolonged drug delivery behavior correlated with the hydrophilicity degree of the matrix. The application of the Multifractal Theory of Motion fitted very well on these findings, the fractality degree accurately describing the changes in hydrophilicity of the polymer. The validation of the model on this series of formulations encourages its further use for other systems, as an easy tool for estimating the drug release toward the design improvement. The present paper is a continuation of the work 'A theoretical mathematical model for assessing diclofenac release from chitosan-based formulations,' published in Drug Delivery Journal, 27(1), 2020, that focused on the consequences induced by the invariance groups of Multifractal Diffusion Equations in correlation with the drug release dynamics. [ABSTRACT FROM AUTHOR]

We conceived a novel hybrid carrier of a thermal-responsive molecularly imprinted polymer (MIP) and a magnetic thermal seed (MTS) that showed a heat-generating ability under an alternate current (AC) magnetic field. Compared to our previous publications, we modify both the MIP and MTS to improve the feasibility for the hybrid carrier, briefly we have to achieve the accurate size control and narrower size distribution of MTS, and higher molecular recognition/release ability of MIP. Firstly, uniformly sized particles which are expected to show a large heat-generating ability under an AC magnetic field were successfully prepared by controlling the core creation. Then, an MIP targeted for selective adsorption of pemetrexed (PMX), a well-known anti-cancer drug, was prepared using N-carbobenzoxy-l-glutamic acid as a pseudo template. Finally, the preliminary hybridization of the MTS and the MIP-equivalent polymer coating was examined by introducing vinyl groups as methacrylic acid using a ligand exchanging method. [ABSTRACT FROM AUTHOR]