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The current work aimed to prepare silymarin (SMR) and metformin (MTH)-loaded nanostructured lipid carriers (NLCs) added in-situ thermoresponsive gel for the treatment of oral cancer. In brief, the nanostructured lipid carriers were designed using Compritol and oleic acid whereas the mucoadhesive sol-gel thermoresponsive system was prepared using gellan gum/Poloxamer. The obtained SMR/MTH-NLCs were characterized for Fourier transform infrared spectroscopy–attenuated total reflectance, scanning electron microscope (SEM), transmission electron microscope (TEM), atomic force microscopy (AFM), particle size, zeta potential, in-vitro release, etc. Moreover, the SMR/MTH-NLCs incorporated gel was characterized for sol-gel temperature, viscosity, ex-vivo mucoadhesion, etc. Here, SMR/MTH-NLCs showed a spherical shape with a particle size of 258.2 ± 1.2 nm and zeta potential − 35 ± 0.2 mV, respectively. Further, the sol-gel transition could form gel at 35.2 ± 0.5 ℃ providing site-specific and sustained release of SMR and MTH. Ex-vivo permeation of formulation exhibited longer retention that confirmed the good mucoadhesion potential of gellan gum. The cell viability studies demonstrated a significant reduction of KB oral cancer cells that confirms the increased synergistic anticancer effects of SMR/MTH-NLCs incorporated gel (IC50 = 0.65 ± 0.12 µM) than free drug combination. These findings illicit the potential of SMR/MTH-NLCs incorporated gel formulation to localize delivery of SMR and MTH at buccal mucosa in the treatment of oral cancer. Highlights: Silymarin and Metformin-loaded Compritol-based lipid nanostructures (SMR/MTH-NLCs) for oral cancer. Addition of SMR/MTH-NLCs in the thermosensitive mucoadhesive gel for sustained release. MTT assay confirmed the improved cytotoxicity of SMR/MTH-NLCs gel in KB oral cancer cells. [ABSTRACT FROM AUTHOR]

The characteristics of commercially available thermochromic ink pens have been studied and described since their appearance in 2006. The wide variety of brands and models now available warrants further study using an expanded sample size, to differentiate the general characteristics from specific characteristics. Herein, the ink strokes of 15 pens purchased in the province of Córdoba, Argentina were studied. First, the initial unaltered strokes were examined. Second, heat-manipulated strokes (with and without friction) were evaluated. Several characterization techniques were employed, such as observation by the naked eye, optical magnification, and light irradiation using different spectral bands. In 100% of the unaltered strokes, the general characteristics of thermochromic inks, such as ink accumulation at the end of the stroke path and a "pasty appearance", were found. It was possible to visualize colourless strokes (i.e. erased strokes) based on their contrast with the paper by shining oblique light at an opposite angle to that of the observation. In addition, the responses to ultraviolet (UV) (365 and 254 nm) and cyan light (505 nm) by infrared techniques were useful for distinguishing the thermochromic ink. Specific characteristics, such as high relief in areas of ink accumulation, less ink accumulation in the internal zone of the stroke, and intensity differences in infrared radiation (IR) luminescence emitted by different brands and models, could be useful in determining the writing tool that was used. Key points Thermochromic ink disappears with heat but is reversible with cold. UV techniques and IR photography serve to make thermochromic ink visible. Initially use oblique white light opposite to the angle of observation to make strokes visible. [ABSTRACT FROM AUTHOR]

Agomelatine (AG), the first-in-class melatonergic antidepressant used in Major Depressive Disorder (MDD), belongs to BCS Class-II with low oral bioavailability (<5%) due to extensive hepatic metabolism. This research work developed a thermosensitive in-situ gel using nanostructured lipid carriers (NLC) for intranasal delivery as alternate route, aiming to bypass hepatic metabolism, enable controlled release, and enhance cerebral distribution. FTIR ensured compatibility with lipids, surfactants and polymers. AG-NLCs were synthesized utilizing hot highspeed homogenization with 5 mg agomelatine dose and optimized with 32 factorial design with total lipids (Precirol® ATO 5:Oleic acid - 70:30) and surfactant concentration (% of Poloxamer 188) as independent two-factor variables. The optimized AG-NLC (AF8) showed particle size of 159.3 nm, zeta potential of -37.0 mV, and 58.14% entrapment efficiency. AF8 was further fabricated into in-situ gels using thermosensitive polymer Poloxamer 407 and sodium alginate as mucoadhesive polymer, with NLCG-4 (with 8% Poloxamer 407) as the optimized in-situ gel formulation. NLCG-4 had 95.16±0.90% drug content, excellent viscosity (1690.65 ±0.40 cP at 37), and gelled at 33.24±0.11? in 10.3±0.38 seconds, ideal for nasal mucosa. NLCG-4 exhibited a complete, prolonged release of 100.01±0.2% over 6 h, and SEM images confirmed spherical particles without aggregation. The above findings suggest that thermosensitive NLC in-situ gel could be a potential novel approach for enhanced direct nose-to-brain delivery of agomelatine, bypassing first-pass metabolism to treat depression. Further in vivo investigations are ongoing to establish and justify clinical applicability of the novel system. [ABSTRACT FROM AUTHOR]

The present study synthesized silver nanoparticles supported on a thermosensitive polymer with a core–shell structure, formed by a polystyrene (PS) core and a poly(N-isopropylacrylamide) (PNIPAM)/Poly(N, N-methylenebisacrylamide) (MBA) shell. The PS core was synthesized via semicontinuous heterophase polymerization at a flow of 0.073 g/min, enabling polystyrene nanoparticles with an average size (Dz) of 35.2 nm to be obtained. In the next stage, the conditions required for polymerization synthesis were established in seeded microemulsion using PS nanoparticles as seed and semicontinuously adding the thermosensitive shell monomer (PNIPAM/MBA) under monomer-flooded conditions to favor shell formation. The non-homopolymerization of PNIPAM/MBA was demonstrated by obtaining nanoparticles with a core–shell structure, with average particle sizes of 41 nm and extremely low and narrow polydispersity index (PDI) values (1.1). The thermosensitive behavior was analyzed by QLS, revealing an average shrinkage of 4.03 nm and a percentage of shrinkage of 23.7%. Finally, silver nanoparticles were synthesized on the core–shell heat-sensitive nanoparticles in a colloidal solution containing the latices, while silver nanoparticles were anchored onto the cross-linked heat-sensitive network via the formation of complexes between the Ag+ ions and the nitrogen contained in the PNIPAM/MBA network, favoring anchorage around the network and maintaining a size of 5 nm. [ABSTRACT FROM AUTHOR]

The delivery of anticancer drugs using nanotechnology is a promising approach aimed at improving the therapeutic efficacy and reducing the toxicity of chemotherapeutic agents. Liposomes were prepared using HSPC: DSPE–PEG–2000: DSPE–PEG2000–maleimide in the ratio of 4:1:0.2 and conjugated with a PSA antibody. Euphorbia milii extract (EME), doxorubicin (Dox), and docetaxel (Doc) encapsulated in temperature–sensitive immunoliposomes were investigated for their activities against the prostate cancer LNCap and DU145 cell lines. Organic extracts of EME leaves, roots, and stems were screened against both cell lines, inhibiting more than 50% of cell culture at concentrations of 10 μg/mL. The immunoliposomes incorporating the EME and docetaxel were active against the LNCap cells when exposed to heat at 39–40 °C. The liposomes not exposed to heat were inactive against the LNCap cells. The developed heat-sensitive immunoliposomes used for the delivery of both the EME and chemotherapeutic agents was able to successfully release the entrapped contents upon heat exposure above the phase transition temperature of the liposome membrane. The heat-sensitive immunoliposomes conjugated with a PSA antibody encapsulated the extract successfully and showed better cell antiproliferation efficacy against the prostate cancer cell lines in the presence of heat.

AbstractAlzheimer’s disease (AD), which is marked by gradual neuronal decline and subsequent loss of cognitive functions and memory, poses significant treatment challenges. The present study involved the development, in vitro, and in vivo evaluation of a novel intranasal mucoadhesive in-situ gel of vinpocetine (VIN) with the aim to target the brain. An innovative gel formulation composed of poloxamer 407, HPMC E15 LV, and citric acid as a solubilizer was developed by 23 Factorial Design. The developed optimal formulation exhibited favorable rheological properties as it displayed ideal gelation time (31.6 ± 1.52 sec), optimum gelling temperature (32 ± 1.0 °C), enhanced mucoadhesive strength (6622 ± 2.64 dynes/cm2), prolonged adhesion (7.22 ± 0.57 hrs) compared with the baseline formulation (F18), and improved drug release in 12 hrs (39.59 ± 1.6%). In vivo, pharmacokinetics revealed a significant increase in Cmax (∼2-fold) and AUC0-t (∼2-fold) in the brain with the in-situ intranasal gel compared to the oral route. In the rat model of AD, in-situ intranasal gel demonstrated significantly greater efficacy (p < 0.001) than oral administration in alleviating AD symptoms as evidenced by behavioral and histological studies. Thus, VIN in-situ gel can be safe and noninvasive for nose-to-brain drug delivery. [ABSTRACT FROM AUTHOR]

Donepezil (DPZ) is a reversible cholinesterase inhibitor used to treat Alzheimer's disease (AD), while with disadvantages such as gastrointestinal side effects after oral administration and poor adherence in the elderly. The purpose of this study was to develop a thermosensitive hydrogels loaded with donepezil nanosuspension (DPZ‐NS‐gel) for transnasal administration to improve brain targeting and reduce peripheral toxicity. The results of powder X‐ray diffraction and differential scanning calorimeter showed that the crystal type of DPZ changed from form II to form C during the grinding process. DPZ‐NS‐gel was obtained by mixing DPZ‐NS into the blank thermosensitive hydrogel constructed with poloxamer 407 and poloxamer 188. DPZ‐NS‐gel was in sol state at 25 °C and formed gel at 33 °C. Compared with DPZ‐NS, the in vitro release of DPZ‐NS‐gel showed the sustained release profile. In vivo studies indicated that DPZ‐NS‐gel by nasal administration may increase the amount of drug entering into the brain. The in vivo safety evaluation showed no severe inflammatory response and pathological change when DPZ‐NS‐gel was administered by nasal administration. This study provided a promising strategy for clinical application in improving the bioavailability of DPZ in the brain, avoiding oral‐induced gastrointestinal side effects and improving medication adherence in the elderly. [ABSTRACT FROM AUTHOR]

In this study, we combined the imprinting technique, temperature‐sensitive polymer, and Pickering emulsion polymerization to prepare a temperature‐sensitive porous imprinted polymer. First, the temperature‐sensitive block polymer PDEA‐b‐P (DEA‐co‐AM) was prepared by reversible‐addition fragmentation chain transfer polymerization, and then a temperature‐sensitive porous ReO4− imprinted polymer (ReO4−‐TPIP) was prepared using the Pickering‐like polymerization technique, which was introduced to the preparation of the imprinted polymer. The structure and morphology of the polymer were characterized by FTIR, SEM‐EDS, and BET. The adsorption experiments showed that the maximum adsorption (Q), separation (R), and desorption (D) of ReO4−‐TPIP were 0.1568 mmol/g, 3.41, and 85.22%, respectively, and the adsorption equilibrium could be reached after 120 min, which decreased to 0.1212 mmol/g, 1.23, and 70.01% after repeated use for 11 times. These results indicate that ReO4−‐TPIP has good adsorption and reusability properties. The adsorption studies showed that ReO4−‐TPIP conformed to the zero‐level kinetic model in the pre‐adsorption stage, the quasi‐one‐level kinetic model in the late stage, and the isothermal adsorption process conformed more to the Langmuir model. In addition, in the secondary leach solution of high‐temperature alloys, the purity of rhenium in the solution increased from 35.4119% to 53.4812% after one adsorption/desorption cycle. The prepared ReO4−‐TPIP provides a new material and strategy for the selective separation and purification of rhenium in complex rhenium‐containing solutions for the industry. [ABSTRACT FROM AUTHOR]

In this paper, poly (acrylamide-co-N-vinylcaprolactam) [poly(AM-co-NVCL)] hydrogels were modified by aqueous solution polymerization using sodium carboxymethyl cellulose (CMC-Na) and Laponite. Their properties were characterized by infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), rheological testing, and scanning electron microscopy (SEM). The swelling kinetics showed that the equilibrium swelling ratio of the xerogel was influenced by the monomer ratio, crosslinking agent, and modifier content. As the Laponite and CMC-Na content increased, the compressive strength of the composite hydrogel increased, while the elongation at break decreased. The modified composite hydrogel exhibited dual sensitivity to pH and temperature. DSC and rheological tests indicated that CMC-Na functioned as a physical crosslinking agent in the system, and with the increase in CMC-Na content, the crosslinking effect was enhanced. SEM demonstrated that the addition of Laponite and CMC-Na increased the number of pores in the hydrogel and decreased the pore size. [ABSTRACT FROM AUTHOR]

In vivo , the temperature inside preovulatory follicles of cows is approximately 1 °C lower than rectal temperature. However, standard bovine oocyte in vitro maturation (IVM) protocols use 38.5 °C based on rectal temperature. This study evaluated the effect of reducing IVM temperature to 37.5 °C on the proteomic profile of oocytes compared to the routine 38.5 °C. Nuclear maturation rate and cumulus cell (CC) expansion (30 COCs per group, 21 replicates) were assessed by observing the first polar body and using a subjective scoring method (0–4). Total nitrite concentrations in the culture medium were measured using the Griess method. Differential proteomics was performed using LC-MS/MS on pooled oocyte samples (500 matured oocytes per group, three replicates), followed by gene ontology enrichment, protein-protein interaction, and putative miRNA target analyses. No significant differences were observed between the groups in nuclear maturation, CC expansion, or nitrite concentration (P > 0.05). A total of 806 proteins were identified, with 7 up-regulated and 12 down-regulated in the treatment group compared to the control. Additionally, 12 proteins were unique to the control group, and 8 were unique to the treatment group. IVM at 37.5 °C resulted in the upregulation of proteins involved in protein folding and GTP binding, and the downregulation of enzymes with oxidoreductase activity and proteins involved in cytoskeletal fiber formation. Furthermore, 43 bovine miRNAs potentially regulating these genes (DES, HMOX2, KRT75, FARSA, IDH2, CARHSP1) were identified. We conclude that IVM of bovine oocytes at 37.5 °C induces significant proteomic changes without impacting nuclear maturation, cumulus cell expansion, or nitrite concentration in the IVM medium. • Temperature reduction during IVM altered the proteomic profile but did not affect nuclear maturation. • The total nitrite concentration in the IVM medium of COCs was similar between groups cultured at 38.5 °C and 37.5 °C • Proteomic analysis identified 12 unique proteins in the control group and 8 unique proteins in the treatment group • IVM at 37.5 °C resulted in the upregulation of proteins involved in protein folding and GTP binding. • 43 bovine miRNAs were found to potentially regulate key genes affected by the temperature change during IVM of bovine oocytes. [ABSTRACT FROM AUTHOR]

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The treatment of colorectal cancer is always a major challenge in the field of cancer research. The number of estimated new cases of colorectal cancer worldwide in 2020 is 1 148 515, and the estimated number of deaths is 576 858, revealing that mortality accounted for approximately half of the disease incidence. The development of new drugs and strategies for colorectal cancer treatment is urgently needed. Thermosensitive injectable hydrogel PDLLA‐PEG‐PDLLA (PLEL) loaded with cabazitaxel (CTX) is used to explore its anti‐tumor effect on mice with orthotopic colorectal cancer. CTX/PLEL is characterized by a solution state at room temperature and a hydrogel state at physiologic temperature. The excipients MPEG‐PCL and PDLLA‐PEG‐PDLLA have good biocompatibility and biodegradability. The simple material synthesis and preparation process renders this system cost‐effective and more conducive to clinical transformation. An orthotopic colorectal cancer model is established by transplantation subcutaneous tumors onto the cecum of mice. According to the results of experiments in vivo, CTX/PLEL significantly inhibits orthotopic colorectal cancer and liver metastasis in mice. The results indicate that CTX/PLEL nanoparticle preparations have high security and excellent anti‐tumor effects, and have great application potential in colorectal cancer therapy. [ABSTRACT FROM AUTHOR]

Simple Summary: Pancreatic cancer is one of the most deadly forms of cancer. Current treatment options often fail because too little of the chemotherapy gets into the cancer. Hyperthermia, or heat treatment, has shown some promise in treating pancreatic cancer and may make it more likely for the chemotherapy to enter into the cancer. This study aims to design liposomes that can increase the amount of chemotherapy reaching pancreatic cancer by targeting the liposomes with hyperthermia. Treatment of pancreatic ductal adenocarcinoma with gemcitabine is limited by an increased desmoplasia, poor vascularization, and short plasma half-life. Heat-sensitive liposomes modified by polyethylene glycol (PEG; PEGylated liposomes) can increase plasma stability, reduce clearance, and decrease side effects. Nevertheless, translation of heat-sensitive liposomes to the clinic has been hindered by the low loading efficiency of gemcitabine and by the difficulty of inducing hyperthermia in vivo. This study was designed to investigate the effect of phospholipid content on the stability of liposomes at 37 °C and their release under hyperthermia conditions; this was accomplished by employing a two-stage heating approach. First the liposomes were heated at a fast rate, then they were transferred to a holding bath. Thermosensitive liposomes formulated with DPPC: DSPC: PEG2k (80:15:5, mole%) exhibited minimal release of carboxyfluorescein at 37 °C over 30 min, indicating stability under physiological conditions. However, upon exposure to hyperthermic conditions (43 °C and 45 °C), these liposomes demonstrated a rapid and significant release of their encapsulated content. The encapsulation efficiency for gemcitabine was calculated at 16.9%. Additionally, fluorescent analysis during the removal of unencapsulated gemcitabine revealed an increase in pH. In vitro tests with BxPC3 and KPC cell models showed that these thermosensitive liposomes induced a heat-dependent cytotoxic effect comparable to free gemcitabine at temperatures above 41 °C. This study highlights the effectiveness of the heating mechanism and cell models in understanding the current challenges in developing gemcitabine-loaded heat-sensitive liposomes. [ABSTRACT FROM AUTHOR]

The excellent physical and chemical properties of palladium(Pd) have made its application and demand increase gradually. Therefore, it is important to develop a new material to efficiently separate and purify palladium from secondary sources to ensure its supply. In this work, a thermosensitive palladium smart imprinted polymer(Pd-T-SIP) was synthesized, which could achieve the efficient separation and purification of Pd. The microstructure and morphology of Pd-T-SIP were characterized. The experimental results showed that the Pd-T-SIP showed the maximum adsorption amount(Q) of 0.1022 mmol/g for Pd(IV), the desorption rate(D) was 83.09%, and it had good reusability. Theoretical studies showed that the adsorption process of Pd-T-SIP was suitable to be described by quasi-first-order model and Langmuir model, which indicated that the adsorption of Pd-T-SIP was monolayer adsorption. Finally, Pd-T-SIP was applied to the platinum group catalyst leach solution, and it could be found that its adsorption/desorption effect was more excellent, with its adsorption amount reaching 0.1558 mmol/L, desorption rate reaching 77.14%, and the palladium purity after one adsorption/desorption cycle increased from 13.75% to 30.62%, and the purity of platinum group metals increased from 40.29% to 73.56% after one adsorption/desorption cycle. [ABSTRACT FROM AUTHOR]

In this paper, analytical solutions are presented for temperature and thermal behavior of a thermosensitive multilayered annular disc due to point heat source. Convective heating is applied to both the innermost and outermost layers. The nonlinearity of the thermal diffusivity equation is dealt using Kirchhoff’s transformation technique. A finite integral transform in the form of Bessel’s function is used to deal with the radial variable r. Fourier transform and angular eigen functions are also used to solve the thermal diffusivity equation. Deflection, resultant forces, shearing forces, resultant moments and thermal stresses are obtained. A mathematical representation is formulated for a 3-layered disc, with the inner, middle and outer layers composed of copper, zinc and aluminum respectively. The results are depicted graphically.

It remains a great challenge to achieve strong and reversible hydrogel adhesion. Hydrogel adhesives also suffer from poor environmental stability due to dehydration. To overcome these problems, here reversible adhesive gels are designed using a new switching mechanism and new solvent. For the first time, the study observes UCST (upper critical solution temperature)‐type thermosensitive behaviors of poly(benzyl acrylate) (PBnA) polymer and gel in menthol:thymol deep eutectic solvents (DESs). The temperature‐induced phase transition allows adjusting cohesive force, and hence adhesion strength of PBnA gels by temperature. To further improve the mechanical and adhesion properties, a peptide crosslinker is used to allow energy dissipation when deforming. The resulting eutectogel exhibits thermal reversible adhesion with a high switching ratio of 14.0. The adhesion strength at attachment state reaches 0.627 MPa, which is much higher than most reversible adhesive hydrogels reported before. The low vapor pressure of DES endows the gel excellent environmental stability. More importantly, the gel can be repeatedly switched between attachment and detachment states. The strong and reversible gel adhesive is successfully used to design soft gripper for the transport of heavy cargos and climbing robot capable of moving on vertical and inverted surface in a manner similar to gecko. [ABSTRACT FROM AUTHOR]

The combination of traditional chemotherapy (CT) with emerging photothermal therapy (PTT) can enhance therapeutic efficiency to tumors with minimimal side effects. Herein, a thermosensitive nanoagent (Au@HGC-DOX-ICG) was successfully fabricated based on the encapsulation of a CT drug (Doxorubicin, DOX) and a photothermal agent (Indocyanine green, ICG) into hexanoyl glycol chitosan (HGC)/gold composite nanoparticles (Au@HGC) for the PTT/CT synergistic therapy of tumors. Under 808 nm laser irradiation, ICG in Au@HGC-DOX-ICG converts light energy into local heat, inducing PTT treatment and the shrinkage of thermosensitive HGC layers coated on gold nanoparticles (AuNPs) to promote the release of loaded DOX, thus achieving excellent cytotoxicity against HeLa and SiHa cell lines, superior to the results of a single PTT or CT modalities. In vivo HeLa tumor-bearing mice models validated the excellent PTT/CT synergistic therapeutic efficiency of the nanoagent. The developed Au@HGC-DOX-ICG nanoagent exhibits promise for applications in PTT/CT synergistic tumor therapy, especially in deep tissue. [ABSTRACT FROM AUTHOR]

We developed an intelligent device capable of controlled release of anti-cancer drugs. The nano-carrier consists of two key components: firstly, magnetic nanoparticles were synthesized through co-precipitation and then functionalized for attaching anti-cancer drugs; secondly, a polymer (poly(N-isopropylacrylamide-co-acrylic acid)) sensitive to pH and temperature was synthesized and employed to encapsulate the drug-loaded magnetic nanoparticles. This responsive polymer exhibits a lower critical solution temperature (LCST) of 38.5 °C, indicating a phase transition behavior. Numerous techniques and analyses, including Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potentials, scanning electron microscope, and transmission electron microscopy, were employed to confirm the successful execution of the aforementioned process. In vitro release assessments of the anti-cancer drug, doxorubicin, were conducted across various media (pH 5–8 and temperatures ranging from 20 to 40 °C). The outcomes revealed higher drug releases at temperatures exceeding the LCST (40 °C) and at slightly acidic pH levels (5–5.3). Notably, compared to the effectiveness of the unloaded drug, the magnetic smart polymer loaded with DOX exhibited a more potent cytotoxic effect. Considering these results, this nano-carrier emerges as a promising candidate for targeted therapeutic delivery to cancerous tissues. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis, in short called as RA, is a severe auto-immune condition characterized by thickening of the synovium joints, inflammation and soreness of joints, which subsequently destroys the articular structures. The drug used to treat RA requires the delivery of a formulation in intact form to synovial joints and release of a whole amount of medicine into synovial fluids. Apremilast is an anti-inflammatory drug used to treat arthritis, but its oral drug delivery is limited because of its low bioavailability and side effects. The nanoparticle-based in situ gel helps in prolonged formulation retention, which enables drug release within specific tissues such as cartilage and synovium. The purpose of this research is to formulate and assess the efficacy of a thermosensitive in situ gel of nanosized apremilast for managing RA. A total of nine apremilast- loaded nanoparticles in situ gels designated as F1–F9 were prepared with different ratios of Eudragit RSPO and polyvinyl alcohol using 25% w/v poloxamer 407 and poloxamer 188 as gelling agents. Among the various formulations, F5 showed a particle size of 119 nm, 80.8% EE, 27.54% DL, 37.5 ± 1.7∘C gelation temperature, 55 ± 1.0 second gelation time and 866 ± 13 cps viscosity, with a better in vitro drug release profile of 75.54% for 24 h by non-Fickian diffusion mechanism; thus, it was chosen as the most productive formulation. In an in vivo study in rats, the optimized formulation reduced inflammation at the test site. The developed nanoparticles in situ gel will be a novel carrier system for drugs used to treat RA. [ABSTRACT FROM AUTHOR]

Thermoresponsive drug delivery systems have been used to treat diseases that cause hyperthermia or elevated body tissue temperatures, viz., rheumatoid arthritis and different cancers. The aim of the study was to enhance berberine (BER) release using thermosensitive nanostructured lipid carriers (TNLCs) through intra-articular administration for the management of arthritis. TNLCs were prepared using binary mixtures of stearic acid and decanoic acid as solid and liquid lipids, respectively. Lipid mixtures with an optimum melting point were assessed using differential scanning calorimetry studies. In vitro characterization of the BER TNLCs included particle size, zeta potential, entrapment efficiency, and drug release at 37 °C and 41 °C. Joint diameter measurement, real-time polymerase chain reaction (RT-PC) analysis, enzyme-linked immunosorbent assay (ELISA) for inflammatory markers, and histological evaluation of the dissected joints were all performed in vivo on rats with adjuvant-induced arthritis. In vitro characterization revealed negatively charged BER-loaded TNLCs with a spherical shape, particle size less than 500 nm, BER entrapment efficiency up to 79%, and a high drug release rate at an elevated temperature of 41 °C. In silico studies revealed the affinity of BER to different formula components and to the measured biomarkers. In vivo assessment of the optimum TNLCs showed that BER TNLCs were superior to the BER solution suspension regarding their effect on inflammatory biomarkers, joint diameter, and histological studies. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize and compare the zeta potential of particles sensitive to external thermal stimuli. Poly N-(isopropyl) acrylamide (PNIPA) was selected as the thermosensitive polymer with a volume phase transition temperature (VPTT) between 32 and 33 °C. The hydrodynamic diameter (DH) of the nanoparticles was measured by dynamic light scattering. Zeta potential (ZP) measurements were performed with the same instrument used for DH measurements. ZP measurements allow the prediction of the stability of colloidal systems in aqueous solutions. These measurements were combined with a pH study before and after the purification process of the particles. The ZP was measured to determine the electrostatic interactions between the particles, which can lead to particle aggregation and decrease their colloidal stability. The effect of the composition of the synthesized particles on the ZP was assessed. One of the most important factors influencing ZP is pH, especially in aqueous solutions. The initiator did not significantly affect the DH of the particles, but it did significantly affect the ZP. The synthesized particles were subjected to a visible radiation absorption study in the selected temperature range to determine the VPTT. [ABSTRACT FROM AUTHOR]

In this paper, analytical solutions are presented for temperature and thermal behavior of a thermosensitive multilayered annular disc due to point heat source. Convective heating is applied to both the innermost and outermost layers. The nonlinearity of the thermal diffusivity Eq.is dealt using Kirchhoff's transformation technique. A finite integral transform in the form of Bessel's function is used to deal with the radial variable r. Fourier transform and angular eigen functions are also used to solve the thermal diffusivity equation. Deflection, resultant forces, shearing forces, resultant moments and thermal stresses are obtained. A mathematical representation is formulated for a 3-layered disc, with the inner, middle and outer layers composed of copper, zinc and aluminum respectively. The results are depicted graphically. [ABSTRACT FROM AUTHOR]

Joint trauma results in the production of inflammatory cytokines that stimulate the secretion of catabolic enzymes, which degrade articular cartilage. Molecular fragments of the degraded articular cartilage further stimulate inflammatory cytokine production, with this process eventually resulting in post-traumatic osteoarthritis (PTOA). The loss of matrix component aggrecan occurs early in the progression of PTOA and results in the loss of compressive stiffness in articular cartilage. Aggrecan is highly sulfated, associates with hyaluronic acid (HA), and supports the compressive stiffness in cartilage. Presented here, we conjugated the HA-binding peptide GAHWQFNALTVRGSG (GAH) to anionic nanoparticles (hNPs). Nanoparticles conjugated with roughly 19 GAH peptides, termed 19 GAH-hNP, bound to HA in solution and increased the dynamic viscosity by 94.1% compared to an HA solution treated with unconjugated hNPs. Moreover, treating aggrecan-depleted (AD) cartilage explants with 0.10 mg of 19 GAH-hNP restored the cartilage compressive stiffness to healthy levels six days after a single nanoparticle treatment. Treatment of AD cartilage with 0.10 mg of 19 GAH-hNP inhibited the degradation of articular cartilage. Treated AD cartilage had 409% more collagen type II and 598% more GAG content than untreated-AD explants. The 19 GAH-hNP therapeutic slowed ECM degradation in AD cartilage explants, restored the compressive stiffness of damaged cartilage, and showed promise as a localized treatment for PTOA.

In this study, a new thermosensitive surface imprinted polymer based on palygorskite was successfully synthesised by a surface imprinting technique and used as an intelligent selective recognition adsorbent for the adsorption of Cu(II) ions from aqueous solution. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) measurements results demonstrated that Cu(II)-imprinted polymer was successfully synthesised. The separation and preconcentration characteristics of Cu(II)-imprinted polymer for Cu(II) were researched by batch and column procedures. optimal intelligent recognition temperature for adsorption is 35°C and intelligent identification and elution of Cu(II) can be achieved by adjusting the temperature. The maximum static adsorption capacity of the ion-imprinted and non-imprinted sorbents for Cu(II) was 35.55 and 9.78 mg g−1, respectively. The relative selectivity factor values (ar) of Cu(II)/Zn(II), Cu(II)/Ni(II), Cu(II)/Co(II) and Cu(II)/Pb(II) were 111.48, 85.37, 98.31 and 73.85 respectively, which were all greater than 1. The Cu(II)-imprinted polymer offered fast kinetics for the adsorption and desorption of Cu(II). Under the optimised conditions (pH-5, temperature-35°C, shaking time-15 min), a detection limit of 0.21 μg L−1 with a relative standard deviation (RSD) of 2.5% for Cu(II) was obtained. Based on Cu(II)-imprinted polymer packed columns, a highly selective pre-concentration method for Cu(II) was established. The accuracy of the method has been certified using national reference materials (GBW 08301). This method has also been successfully used for the determination of Cu (II) in locally collected water samples. [ABSTRACT FROM AUTHOR]

We have prepared a pH and thermosensitive, fluorescent nanogel based on sodium alginate and itaconic acid as pH-sensitive moieties, diethylene glycol methyl ether acrylate as thermosensitive monomer and rhodamine B monomer as pH-sensitive fluorescent dye. The nanogel was characterized by Fourier transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1HNMR) spectroscopy. Also, scanning electron microscope (SEM) images were taken and indicated the relative uniform spherical particles with average diameter 250–300 nm. By enhancing the fluorescence emission at 576 nm, we confirmed that the pH sensitive property of the nanogel was more effective than that of the bare rhodamin B. Moreover, the nanogel including the diethylene glycol methyl ether acrylate exhibited changes in fluorescence intensity induced by temperature. By heating the nanogel dispersion to 40 °C, at acidic pH the rhodamine emission showed a considerable increase. This result indicated the occurrence of an efficient fluorescence resonance energy transfer (FRET) process between fluorescence dye and polymeric nanogel in collapsed state. Also, the thermo-responsibility of the nanogel was studied by dynamic light scattering (DLS) analysis which indicated the change in hydrodynamic diameter by changing the temperature. [ABSTRACT FROM AUTHOR]

Sonogenetics has emerged as a tool of therapeutic ultrasound which is revolutionizing the ability to non-invasively modulate the activity of neurons and other excitatory cells. This technology utilizes bioengineering methods to confer or amplify ultrasound sensitivity in target cells using engineered or modified protein mediators. The neuromodulation community has shown a growing interest in sonogenetics due to ultrasound's ability to penetrate the skull and reach deep brain tissue, enabling non-invasive modulation of neurons. Novel methods of sonogenetics aim to enhance cellular control in humans by leveraging mechanosensitive and thermosensitive cellular mechanisms activated by ultrasound to address cellular dysfunction and degeneration. This mini review summarizes the progress of sonogenetic mediators proposed for neuromodulation and looks at new therapeutic applications of sonogenetics for cancer treatment and vision restoration. [ABSTRACT FROM AUTHOR]

The synthesis of a porous shape‐changing interpenetrating network (IPN) bioink for the fabrication of large‐scale (cm) reversibly thermosensitive structures is described. The poly(N‐isopropylacrylamide) (PNIPAm) IPN is generated in situ within an ionically crosslinked alginate hydrogel at room temperature and under aerobic conditions using a horseradish peroxidase (HRP)/glucose oxidase (GOx) bienzymatic initiation system. Mechanical testing assessment of the IPN hydrogels confirm mechanical reinforcement via covalent single network interdigitation. Furthermore, the thermosensitive bioink can be used to print biohybrid reactors containing genetically engineered phosphotriesterase‐expressing E. coli capable of hydrolyzing toxic organophosphorus compounds. Herein, increasing the bioink pore size using the contractile‐thermosensitive response of the IPN improves the temperature‐dependent theoretical mass‐transfer‐limited enzyme catalyzed reaction rate, providing a plausible route to externally regulated enzymatic catalysis within bioprinted structures. [ABSTRACT FROM AUTHOR]

In this study, we synthesize a hyaluronic acid-g-poly(N-isopropylacrylamide) (HPN) copolymer by grafting the amine-terminated poly(N-isopropylacrylamide) (PNIPAM-NH2) to hyaluronic acid (HA). The 5% PNIPAM-NH2 and HPN polymer solution is responsive to temperature changes with sol-to-gel phase transition temperatures around 32 °C. Compared with the PNIPAM-NH2 hydrogel, the HPN hydrogel shows higher water content and mechanical strength, as well as lower volume contraction, making it a better choice as a scaffold for chondrocyte delivery. From an in vitro cell culture, we see that cells can proliferate in an HPN hydrogel with full retention of cell viability and show the phenotypic morphology of chondrocytes. In the HPN hydrogel, chondrocytes demonstrate a differentiated phenotype with the upregulated expression of cartilage-specific genes and the enhanced secretion of extracellular matrix components, when compared with the monolayer culture on tissue culture polystyrene. In vivo studies confirm the ectopic cartilage formation when HPN was used as a cell delivery vehicle after implanting chondrocyte/HPN in nude mice subcutaneously, which is shown from a histological and gene expression analysis. Taken together, the HPN thermosensitive hydrogel will be a promising injectable scaffold with which to deliver chondrocytes in cartilage-tissue-engineering applications. [ABSTRACT FROM AUTHOR]

The optimal treatment of diabetes (in particular, type 1 diabetes—T1D) remains a challenge. Closed-loop systems (implants/inserts) provide significant advantages for glucose responsivity and providing real-time sustained release of rapid-acting insulin. Concanavalin A (ConA), a glucose affinity agent, has been used to design closed-loop insulin delivery systems but not without significant risk of leakage of ConA from the matrices and poor mechanical strength of the hydrogels impacting longevity and control of insulin release. Therefore, this work focused on employing a thermoresponsive co-forming matrix between Pluronic F-127 (PL) and structurally robust chitosan (CHT) via EDC/NHS coupling (i.e., covalent linkage of -NH2 from CHT and ConA to the -COOH of PL). The system was characterized for its chemical structure stability and integrity (FTIR, XRD and TGA), injectability, rheological parameters and hydrogel morphology (Texture Analysis, Elastosens TM Bio2 and SEM). The prepared hydrogels demonstrated shear-thinning for injectability with a maximum force of 4.9 ± 8.3 N in a 26G needle with sol–gel transitioning from 25 to 38 °C. The apparent yield stress value of the hydrogel was determined to be 67.47 Pa. The insulin loading efficiency within the hydrogel matrix was calculated to be 46.8%. Insulin release studies revealed glucose responsiveness in simulated glycemic media (4 and 10 mg/mL) over 7 days (97%) (305 nm via fluorescence spectrophotometry). The MTT studies were performed over 72 h on RIN-5F pancreatic cells with viability results >80%. Results revealed that the thermoresponsive hydrogel is a promising alternative to current closed-loop insulin delivery systems. [ABSTRACT FROM AUTHOR]

Inflammation following joint trauma contributes to cartilage degradation and progression of post traumatic osteoarthritis (PTOA). Therefore, drug delivery vehicles that deliver effective anti-inflammatory treatments have the potential to prevent PTOA. We have developed solid and hollow, thermoresponsive nanoparticles for the controlled release of our anti-inflammatory MK2-inhibiting (MK2i) peptide for intra-articular injection to halt inflammation that contributes to the advancement of PTOA. This system exploits the thermosensitive characteristic of N-isopropyl acrylamide (NIPAm) to transition phases when passing through its lower critical solution temperature (LCST). The nanoparticles (NPs) swell below the LCST and constrict above it. Non-crosslinked poly(NIPAm) (pNIPAm), held above its LCST, formed hydrophobic cores around which shells composed of NIPAm, degradable crosslinker N, N'-bis (acryloyl) cystamine (BAC), sulfated 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS), and acrylic acid (AAc) were polymerized. Removal of the non-crosslinked pNIPAm cores via diffusion produced thermosensitive, degradable nanoparticles with low density, or hollow, cores. The data presented here revealed low-density, termed hollow, nanoparticles (hNPs) load and release significantly more MK2i than solid nanoparticles (sNPs). Furthermore, drug loading below the LCST of NIPAm results in roughly 2.5 times more therapeutic encapsulation compared to loading particles in their constricted state. Hollow nanoparticles increase drug loading compared to solid nanoparticles, are taken up into chondrocytes within 24 h, cleared from the cells within 6 days, significantly decrease the secretion of the proinflammatory cytokine IL-6, and, via intra-articular injection, are successfully delivered into the joint space of rats. The peptide loaded nanoparticles provide a reproducible platform for intra-articular delivery of therapeutics.

A thermal-sensitive molecularly imprinted optosensing probe based on fluorescent advanced glycation end products (AGEs) was prepared by one-pot hydrothermal synthesis. Carbon dots (CDs) derived from fluorescent AGEs were used as the luminous centers, while molecularly imprinted polymers (MIPs) were wrapped outside of the CDs to form specific target recognition sites to highly selectively adsorb the intermediate product of AGEs of 3-deoxyglucosone (3-DG). Thermosensitive N-isopropylacrylamide (NIPAM) was combined with acrylamide (AM) as co-functional monomers, and ethylene glycol dimethacrylate (EGDMA) was chosen as a cross-linker for targeting identification and detection of 3-DG. Under optimal conditions, the fluorescence of MIPs could be gradually quenched with the adsorption of 3-DG on the surface of MIPs in the linear range of 1–160 μg/L, and the detection limit was 0.31 μg/L. The spiked recoveries of MIPs ranged from 82.97 to 109.94% in two milk samples, and the relative standard deviations were all less than 1.8%. In addition, the inhibition rate for non-fluorescent AGEs of pyrraline (PRL) was 23% by adsorbing 3-DG in the simulated milk system of casein and d-glucose, indicating that temperature-responsive MIPs not only could detect the dicarbonyl compound 3-DG quickly and sensitively, but also had an excellent inhibitory effect on AGEs. [ABSTRACT FROM AUTHOR]

In this study, after producing Poly N-isopropylacryl amide (PNIPAAm) nanoparticles by a novel method including a combination of the UV photopolymerization technique and the liposomal nanoreactors approach, which resulted in homogenous, nanosized PNIPAAm nanoparticles, gelatin/PNIPAAm hydrogels were prepared. An investigation of the effect of monomer, crosslinking agent, and nanoparticle concentrations to gelatin weight percent on the morphology, size, structure, phase transition temperature, swelling, and biodegradability of the nanocomposite hydrogels were carried out. The response surface method (RSM) was used to develop models for predicting and optimizing the hydrogels. Fourier-transform infrared spectroscopy (FTIR) spectra of the monomer, polymers, and nanocomposites indicated the incorporation of the poly N-isopropylacrylamid (PNIPAAm) nanoparticles and gelatin in the structure. Based on scanning electron microscope (SEM) images and dynamic light scattering (DLS) results, the size of the nanoparticles was 250–300 nm which were dispersed well in the gelatin hydrogel. In addition, the nanocomposites showed 80–110% swelling in water, a phase transition temperature (LCST) around 32.5 °C and a biodegradation capability under physiological conditions. [ABSTRACT FROM AUTHOR]

Musculoskeletal impairments, especially cartilage and meniscus lesions, are some of the major contributors to disabilities. Thus, novel tissue engineering strategies are being developed to overcome these issues. In this study, the aim was to investigate the biocompatibility, in vitro and in vivo, of a thermosensitive, injectable chitosan-based hydrogel loaded with three different primary mesenchymal stromal cells. The cell types were human adipose-derived mesenchymal stromal cells (hASCs), human bone marrow stem cells (hBMSCs), and neonatal porcine infrapatellar fat-derived cells (IFPCs). For the in vitro study, the cells were encapsulated in sol-phase hydrogel, and then, analyzed via live/dead assay at 1, 4, 7, and 14 days to compare their capacity to survive in the hydrogel. To assess biocompatibility in vivo, cellularized scaffolds were subcutaneously implanted in the dorsal pouches of nude mice and analyzed at 4 and 12 weeks. Our data showed that all the different cell types survived (the live cell percentages were between 60 and 80 at all time points in vitro) and proliferated in the hydrogel (from very few at 4 weeks to up to 30% at 12 weeks in vivo); moreover, the cell-laden hydrogels did not trigger an immune response in vivo. Hence, our hydrogel formulation showed a favorable profile in terms of safety and biocompatibility, and it may be applied in tissue engineering strategies for cartilage and meniscus repair. [ABSTRACT FROM AUTHOR]

The present study aimed to develop and investigate besifloxacin (BSF) in situ gel nanoemulsions (NEs) consisting of two hydrophilic polymers, that is, poloxamer 407 (P407) and poloxamer 188 (P188), for ocular delivery. BSF loaded in situ gel-NEs containing triacetin (oil), Cremophor®RH 40 (surfactant), Transcutol®P (co-surfactant), poloxamer 407 and poloxamer 188 (gelling agents) were prepared by spontaneous emulsification method. The optimum in situ gel nanoemulsion was selected based on gelation temperature. The selected formulation was evaluated for physicochemical characteristics, including droplet size, refractive index, pH, transparency, and viscosity. Further investigations such as in vitro drug release, ex vivo corneal permeation, HET-CAM, pre-corneal residence time antibacterial efficacy studies were conducted too. Developed BSF in situ gel nanoemulsion showed acceptable physicochemical properties with a nano-metric droplet size of 19 nm and PDI of 0.21. Moreover, In vitro release studies revealed that the in situ gel formulation could sustain drug release as only 40% of the BSF was released within 1 h. Permeability coefficient (Papp) of BSF through the excised bovine cornea was found 6.01 × 10−6 cm/s during 6 h. In addition, the HET-CAM evaluation confirmed the non-irritancy of the optimum BSF in situ gel NEs. The pre-corneal residence time evaluation indicated prolonged retention of in situ gel-NEs on the eye surface. Finally, antibacterial susceptibility investigations illustrated remarkable efficacy against Pseudomonas aeruginosa and Staphylococcus aureus. The current findings demonstrated that this proposed BSF-loaded in situ gel-NEs could be considered as a potential novel drug delivery formulation against ophthalmic bacterial infections. [ABSTRACT FROM AUTHOR]

In this study, a thermosensitive in situ gel with porous structure was developed using poloxamer (Po) and N-(2-hydroxy-3-trimethyl ammonium) propyl chitosan chloride (HTCC). The poloxamer-quaternized chitosan (Po-HTCC) in situ gel exhibited superior rheological property, water absorption capacity and antibacterial activity against Escherichia coli , Staphylococcus aureus , Pseudomonas aeruginosa and Streptococcus pyogenes , making it well-suited for ocular applications. Scanning electron microscope revealed a macroporous architecture with pore sizes ranging from 1 to 2 μm, suggesting that the gel has desirable breathability, corneal adhesion capability, and overall conformability. In vitro drug release assay was conducted with levofloxacin hydrochloride, demonstrating that sustained release over 48 h could be achieved at 34 °C, with approximately 80 % of the drug released within this timeframe. Computational simulations revealed substantial binding affinity between the material and the Escherichia coli outer membrane lipopolysaccharide-associated protein and corneal mucin. The protein showing the strongest binding energy to N-(2-hydroxy-3-trimethyl ammonium) propyl chitosan chloride (HTCC), as calculated by the Molecular Mechanics Generalized Born Surface Area Method (MM-GBSA), was LptD-LptE, with a binding energy of −61.14 ± 4.72 kcal/mol. These results underscore the potential of this system for effective and convenient ocular delivery with sustained drug release. [Display omitted] • Poloxamer-quaternized chitosan in situ gel was prepared. • The in situ gel is thermosensitive and suitable for ocular drug delivery. • The gel is antimicrobial and capable of sustained release of drug. • Molecular simulation results proved good binding between the gel and target proteins. [ABSTRACT FROM AUTHOR]

Burns are the fourth most common type of civilian trauma worldwide, and the management of severe irregular scald wounds remains a significant challenge. Herein, crocin-1 laden hydroxybutyl chitosan (CRO-HBC) thermosensitive hydrogel with smart anti-inflammatory performance was developed for accelerating full-thickness burn healing. The injectable and shape adaptability of the CRO-HBC gel make it a promising candidate for effectively filling scald wounds with irregular shapes, while simultaneously providing protection against external pathogens. The CRO-HBC gel network formed by hydrophobic interactions exhibited an initial burst release of crocin-1, followed by a gradual and sustained release over time. The excessive release of ROS and pro-inflammatory cytokines should be effectively regulated in the early stage of wound healing. The controlled release of crocin-1 from the CRO-HBC gel adequately addresses this requirement for wound healing. The CRO-HBC hydrogel also exhibited an excellent biocompatibility, an appropriate biodegradability, keratinocyte migration facilitation properties, and a reactive oxygen species scavenging capability. The composite CRO-HBC hydrogel intelligently mitigated inflammatory responses, promoted angiogenesis, and exhibited a commendable efficacy for tissue regeneration in a full-thickness scalding model. Overall, this innovative temperature-sensitive CRO-HBC injectable hydrogel dressing with smart anti-inflammatory performance has enormous potential for managing severe scald wounds. [Display omitted] [ABSTRACT FROM AUTHOR]

BACKGROUND: Ventriculoperitoneal shunts (VPSs) have been the mainstay of treating hydrocephalus since the 1950s. However, shunts have a reported complication rate reaching nearly 50%. Devices have been developed that utilize noninvasive thermal transcutaneous diffusion technology. These shunt evaluation devices measure temperature gradients to detect shunt cerebrospinal fluid flow. We assessed the utility using a thermal diffusion technique to work up shunt failure in the emergency room (ER). METHODS: This was a retrospective case series at a single medical center ER. We included consecutive patients with possible VPS malfunction who were evaluated with a thermal sensor. The time period of data collection included September 2015-April 2018. RESULTS: Eight patients were reviewed, including four males and four females. The average age of reviewed patients was 35.1 (+/- ; 16.5). In our case series, three patients had adequate shunt flow as assessed by the shunt evaluation device, and the decision was made to discharge the patient and follow-up in clinic. In two patients, the flow was diminished, but due to other reassuring signs, the patients were still discharged with follow-up. Two patients were noted to have poor flow and were admitted for shunt revision. CONCLUSION: It is important to determine whether a malfunction is present and whether an intervention is necessary for patients who present to the emergency department with possible symptoms of shunt failure. A thermal sensor is a fast and noninvasive tool in the evaluation of shunt flow and helps determine whether it is safe to send a patient home or intervene appropriately.

Chronic wound infections with antibiotic-resistant bacteria have become a significant problem for modern healthcare systems since they are often associated with high costs and require profound topical wound management. Successful wound healing is achieved by reducing the bacterial load of the wound and providing an environment that enhances cell growth. In this context, nanofibers show remarkable success because their structure offers a promising drug delivery platform that can mimic the native extracellular matrix and accelerate cell proliferation. In our study, single-needle electrospinning, a versatile and cost-efficient technique, was used to shape polymers into an applicable and homogeneous fleece capable of a photothermally triggered drug release. It was combined with antimicrobial photodynamic therapy, a promising procedure against resistant bacteria. Therefore, poly(d,l-lactide) nanofibers loaded with curcumin and indocyanine green (ICG) were produced for local antimicrobial treatment. The mesh had a homogeneous structure, and the nanofibers showed a smooth surface. Recordings with a thermal camera showed that near-infrared light irradiation of ICG increased the temperature (>44 °C) in the surrounding medium. Release studies confirmed more than 29% enhanced curcumin release triggered by elevated temperature. The antimicrobial activity was tested against the gram-positive strain Staphylococcus saprophyticus subsp. bovis and the gram-negative strain Escherichia coli DH5 alpha. The nanofibers loaded with both photosensitizers and irradiated with both wavelengths reduced the bacterial viability (~4.4 log10, 99.996%) significantly more than the nanofibers loaded with only one photosensitizer (<1.7 log10, 97.828%) or irradiated with only one wavelength (<2.0 log10, 98.952%). In addition, our formulation efficiently eradicated persistent adhered bacteria by >4.3 log10 (99.995%), which was also confirmed visually. Finally, the produced nanofibers showed good biocompatibility, proven by the cellular viability of mouse fibroblasts (L929). The data demonstrate that we have developed a new economic nanofiber formulation, which offers a triggered drug release, excellent antimicrobial properties, and good biocompatibility. [ABSTRACT FROM AUTHOR]

In this research, we studied, in detail, the behavior of common PNIPAM microgels, obtained through surfactant-free precipitation polymerization, in a number of organic solvents. We showed that many of the selected solvents serve as good solvents for the PNIPAM microgels and that the size and architecture of the microgels depend on the solvent chosen. Expanding the range of solvents used for PNIPAM microgel incubation greatly enhances the possible routes for microparticle functionalization and modification, as well as the encapsulation of water-insoluble species. In this demonstration, we successfully encapsulated water-insoluble Sudan III dye in PNIPAM microgels and prepared the aqueous dispersions of such composite-colored microparticles. [ABSTRACT FROM AUTHOR]

In this study, a novel thermosensitive polymer poly(styrene co acrylonitrile co methacrylic acid co n-butylacrylate co diviniyl benzene)(SAMB) is synthesized by solvent polymerization and by copolymerization of styrene, acrylonitrile, methacrylic acid, n-butyl acrylate as a monomer, divinyl benzene as crosslinking agent and benzoyl peroxide as a initiator and poly(styrene co acryl amidoxime co methacrylic acid co n-butyl acrylate co divinyl benzene)(SAMB-Aox) is synthesized by amidoxymation of hydroxilamine hydrochloride, NH2OH·HCl. Firstly, the structure of SAMB and SAMB-Aox is characterized by FTIR, morphology of these polymers is determined by SEM and XRD, thermal properties of SAMB and SAMB-Aox also is specified by DSC and DMA and finally shape memory properties of these polymers were analyzed by bending test SAMB in 45 ℃ and SAMB-Aox at 75 ℃. The shape memory property of SAMB has a Rf value of 76% in 9 s, while the Rf value of SAMB-Aox was measured as 33.3% in 42 s. It was observed that shape recovery value decreased due to the effect of interchain hydrogen bonds after amidoxymation of the polymer. [ABSTRACT FROM AUTHOR]

The characteristics of commercially available thermochromic ink pens have been studied and described since their appearance in 2006. The wide variety of brands and models now available warrants further study using an expanded sample size, to differentiate the general characteristics from specific characteristics. Herein, the ink strokes of 15 pens purchased in the province of Córdoba, Argentina were studied. First, the initial unaltered strokes were examined. Second, heat-manipulated strokes (with and without friction) were evaluated. Several characterization techniques were employed, such as observation by the naked eye, optical magnification, and light irradiation using different spectral bands. In 100% of the unaltered strokes, the general characteristics of thermochromic inks, such as ink accumulation at the end of the stroke path and a "pasty appearance", were found. It was possible to visualize colourless strokes (i.e. erased strokes) based on their contrast with the paper by shining oblique light at an opposite angle to that of the observation. In addition, the responses to ultraviolet (UV) (365 and 254 nm) and cyan light (505 nm) by infrared techniques were useful for distinguishing the thermochromic ink. Specific characteristics, such as high relief in areas of ink accumulation, less ink accumulation in the internal zone of the stroke, and intensity differences in infrared radiation (IR) luminescence emitted by different brands and models, could be useful in determining the writing tool that was used., Key Points: Thermochromic ink disappears with heat but is reversible with cold.UV techniques and IR photography serve to make thermochromic ink visible.Initially use oblique white light opposite to the angle of observation to make strokes visible., (© The Author(s) 2024. Published by OUP on behalf of the Academy of Forensic Science.)

Endometritis, a prevalent obstetric condition primarily caused by Escherichia coli ( E. coli) and Staphylococcus aureus ( S. aureus ), significantly threatens the reproductive performance of female animals. In this study, thermosensitive injectable chitosan (CS)/β-glycerophosphate (β-GP) hydrogels loaded with berberine (BBR) and carvacrol (CAR) were prepared for endometritis treatment. In vitro , BBR/CAR-CS/β-GP hydrogels exhibited rapid gelation within 5 min at 37 °C, excellent injectability, and more than 90% degradation within 30 days under enzymatic action. The dual drug-loaded system also exhibited controlled release of BBR and CAR and demonstrated the antimicrobial activity against E. coli and S. aureus . In vivo , uterine injection of BBR/CAR-CS/β-GP hydrogels alleviated infection-induced injuries and reduced the bacterial load in infected uterine tissues. In summary, these findings highlight the potential of BBR/CAR-CS/β-GP hydrogels as innovative carriers for drug delivery targeting endometritis.

The optimal treatment of diabetes (in particular, type 1 diabetes—T1D) remains a challenge. Closed-loop systems (implants/inserts) provide significant advantages for glucose responsivity and providing real-time sustained release of rapid-acting insulin. Concanavalin A (ConA), a glucose affinity agent, has been used to design closed-loop insulin delivery systems but not without significant risk of leakage of ConA from the matrices and poor mechanical strength of the hydrogels impacting longevity and control of insulin release. Therefore, this work focused on employing a thermoresponsive co-forming matrix between Pluronic F-127 (PL) and structurally robust chitosan (CHT) via EDC/NHS coupling (i.e., covalent linkage of -NH2 from CHT and ConA to the -COOH of PL). The system was characterized for its chemical structure stability and integrity (FTIR, XRD and TGA), injectability, rheological parameters and hydrogel morphology (Texture Analysis, Elastosens TM Bio2 and SEM). The prepared hydrogels demonstrated shear-thinning for injectability with a maximum force of 4.9 ± 8.3 N in a 26G needle with sol–gel transitioning from 25 to 38 °C. The apparent yield stress value of the hydrogel was determined to be 67.47 Pa. The insulin loading efficiency within the hydrogel matrix was calculated to be 46.8%. Insulin release studies revealed glucose responsiveness in simulated glycemic media (4 and 10 mg/mL) over 7 days (97%) (305 nm via fluorescence spectrophotometry). The MTT studies were performed over 72 h on RIN-5F pancreatic cells with viability results >80%. Results revealed that the thermoresponsive hydrogel is a promising alternative to current closed-loop insulin delivery systems.