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Within this study we report a non-toxic nanomaterial suitable for Photodynamic Therapy (PDT) under hypoxic conditions. PDT relies on the production of reactive oxygen and nitrogen species that can lead to cancer cells death. Currently, PDT is limited by: the development of efficient photosensitizers that can produce these radicals in situ; and the oxygen level requirement. The produced Carbon Dots (Cdots) successfully destroy human melanoma cancer cells upon 5 min irradiation using 450 nm wavelength due to the in situ production of NO•. As such, this nanophotosensitizer is applicable regardless of the cells molecular oxygen levels. Additionally, this nanomaterial acts as a scavenging nanozyme biosensor allowing to follow-up, in situ, the released NO• concentration, thereby offering a tight control over the NO• concentration in real-time and, its maintenance within the therapeutic window. Hence, this work offers a novel theranostic and NO• scavenging nanozyme biosensing nanoplatform that allows high control for hypoxic-PDT cancer application even in low doses and with 5 min irradiation.

Highlights Naturally crosslinked carbonaceous liquid metal aqueous printable ink mediated by biopolymers. E-textile with conductivity, stability, wearability, and aesthetic characteristics. Multi-applications in health monitoring, pressure sensing, and energy harvesting.

In this study, we demonstrate the potential of the bornite crystal structure (Cu5FeS4) of copper iron sulfide as a second near infrared (NIR-II) photoacoustic (PA) contrast agent. Bornite exhibits comparable dose-dependent biocompatibility to copper sulfide nanoparticles in a cell viability study with HepG2 cells, while exhibiting a 10-fold increase in PA amplitude. In comparison to other benchmark contrast agents at similar mass concentrations, bornite demonstrated a 10× increase in PA amplitude compared to indocyanine green (ICG) and a 5× increase compared to gold nanorods (AuNRs). PA signal was detectable with a light pathlength greater than 5 cm in porcine tissue phantoms at bornite concentrations where in vitro cell viability was maintained. In vivo imaging of mice vasculature resulted in a 2× increase in PA amplitude compared to AuNRs. In summary, bornite is a promising NIR-II contrast agent for deep tissue PA imaging.

Amino acids are indispensable compounds in the body, performing several biological processes that enable proper functioning. In this work, it is demonstrated that a single amino acid, taurine, is also able to promote the ring‐opening polymerization (ROP) of several cyclic monomers under industrially relevant conditions. It is shown that the unique zwitterionic structure of taurine, where the negatively charged sulfonic acid group and the protonated amine group are separated by two methylene groups, not only provides high thermal stability but also leads to a dual activation mechanism, which is corroborated by quantum mechanical calculations. This unique mechanism allows for the synthesis of polylactide of up to 50 kDa in bulk at 180 °C with good end‐group fidelity using a highly abundant catalyst. Furthermore, cytotoxicity tests confirm that PLLA synthesized with taurine is non‐toxic. Moreover, it is demonstrated that the presence of taurine does not have any detrimental effect on the thermal stability of polylactide, and therefore polymers can be used directly without any post‐polymerization purification. It is believed that the demonstration that a simple structure composed of a single amino acid can promote polymerization can bring a paradigm shift in the preparation of polymers. [ABSTRACT FROM AUTHOR]

The development of multidrug-resistant bacterial infections seriously threatens public health. Hence, efforts are needed to develop a class of safe and effective antibacterial agents. Here, we report the synthesis of surface-modified molybdenum disulfide nanoflowers using a biogenic capping agent l-cysteine (MoS2-cys NFs). The morphological characterizations confirm the flower-like morphology with a 537 ± 12 nm size. Further, structural and surface investigations confirm the formation of the hexagonal phase of NFs and modification by l-cysteine. Also, the surface alteration of NFs by l-cysteine contributes to enhanced colloidal stability in aqueous media. The as-prepared MoS2-cys NFs exhibit excellent bactericidal activity against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria. The scanning electron microscopy images of the bacteria confirm the membrane-directed antibacterial mechanisms, where the nanosheets in the NFs act as nanoblades and cause cell membrane damage. The antibacterial mechanisms of MoS2-cys NFs are primarily attributed to membrane damage and the generation of oxidative stresses, which destroy both bacterial strains. The generation of oxidative stress can occur through reactive oxygen species-dependent and -independent pathways validated using flow cytometry and fluorescence imaging with DCFH-DA staining and Ellman's assay, respectively. The excessive generation of ROS leads to inactivation of the bacterial antioxidant defense mechanism. The toxicity studies of the MoS2-cys NFs toward human foreskin fibroblast cell lines suggested good biocompatibility with a cell viability of nearly 90%. We report an excellent intrinsic antibacterial efficiency of MoS2-cys NFs without any external stimulus (light, H2O2, etc.), additional functionalization or complexation, doping, drug loading, etc. Our study indicates that the appropriate surface modification of the flower-like morphology of MoS2 can enhance their colloidal stability and intrinsic antibacterial potency for further applications such as antibacterial coatings, water disinfection, and wound healing. [ABSTRACT FROM AUTHOR]

Interest in synthesizing functional materials from natural compounds has increased recently. For this reason, compound particles attract attention due to their multifunctional properties. Abelmoschus esculentus L. (Okra) is a vegetable species belonging to the Hibiscus family, widely used for its edible unripe fruit. This study synthesized the particle from the Abelmoschus esculentus (Okra) extract (Oe) by emulsion polymerization. In this synthesis, ammonium persulfate (APS, initiator) to form free radicals at the Abelmoschus esculentus (Okra) extract (Oe) and ethylene glycol di methacrylate to cross-link the formed radicals were used. The synthesized poly(Okra) ((p(O)) particles structure Field emission scanning and Fourier transform infrared and biological activities (biocompatible, antioxidant, antimicrobial, and hydrogen peroxide scavenging) were characterized. The p(O) particle showed good antimicrobial activity against Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis, and Candida albicans. It has been measured to have high antioxidant and hydrogen peroxide scavenging activity with p(O) particles. [ABSTRACT FROM AUTHOR]

Antibiotic resistance is an escalating global health threat. Due to their diverse mechanisms of action and evasion of traditional resistance mechanisms, peptides hold promise as future antibiotics. Their ability to disrupt bacterial membranes presents a potential strategy to combat drug‐resistant infections and address the increasing need for effective antimicrobial treatments. Amphipathic α‐helical peptides possess a distinctive molecular structure with both charged/hydrophilic and hydrophobic regions that interact with the bacterial cell membrane, disrupting its structural integrity. The α‐helical amphipathic peptide aurein 1.2, secreted by the Australian frog Litoria aurea, is one of the shortest known antimicrobial peptides, spanning only 13 amino acids. The primary objective of this study was to investigate stapled and photoswitchable modifications of short helical peptides employing biocompatible chemistry, utilising aurein 1.2 as a model system. We developed various stapled versions of aurein 1.2 using biocompatible conjugation chemistry between dicyanopyridine and 1,2‐aminothiols. While the commonly employed stapling pattern for longer staples is i, i + 7, we observed superior helicity in peptides stapled at positions i, i + 8. Molecular dynamics simulations confirmed both stapling patterns to support an α‐helical peptide conformation. Additionally, we utilised a cysteine‐selective photosensitive staple, perfluoro azobenzene, to explore photoswitchable variants of aurein 1.2. A double‐cysteine variant stapled at i, i + 7 indeed exhibited a change in overall helicity induced by light. We further demonstrated the applicability of this staple to attach to cysteine residues in i, i + 7 positions of a helix in a model protein. While some of the stapled variants displayed substantial increase in helicity, minimal inhibitory concentration assays revealed that none of the stapled aurein 1.2 variants exhibited increased antimicrobial activity compared to the wildtype. [ABSTRACT FROM AUTHOR]

The surface treatment of metallic implants is significant for their in-vivo performance. Biocompatible coatings play a crucial role in corrosion protection and other practical uses of biomedical devices to evade surgery failure and enhance their functions. Polydopamine (PDA), a mussel-inspired synthetic polymer, exhibits high potential as an adhesive middle layer to enhance the bonding at the interface between the metal substrate and coating materials and used for corrosion protection of the implants. Owing to its excellent biocompatibility along with unique drug loading perspective, several PDA-modified nanoparticles have also been preferred as drug carriers. This featured article is dedicated to summarizing the significance of PDA as a coating material for clinical applications. It was begun by describing the polymerization process of dopamine and then describes the PDA as an effective coating material for corrosion protection of implants with proposed mechanism. The beneficial effects of PDA containing coatings on corrosion protection of implants were also discussed. Next, was focused on PDA-modified nanostructures and emphasized the biocompatibility of PDA. The latest developments of PDA modified coatings/nanoparticles in advanced drug delivery applications were also discussed. [ABSTRACT FROM AUTHOR]

Aim: The development of carbon quantum dots (C-QDs) as nanotrackers to understand drug–pathogen interactions, virulence and multidrug resistance. Methods: Microwave synthesis of C-QDs was performed using citric acid and polyethylene glycol. Further, in vitro toxicity was evaluated and imaging applications were demonstrated in Candida albicans isolates. Results: Well-dispersed, ultra small C-QDs exhibited no cyto/microbial/reactive oxygen species-mediated toxicity and internalized effectively in Candida yeast and hyphal cells. C-QDs were employed for confocal imaging of drug-sensitive and -resistant cells, and a study of the yeast-to-hyphal transition using atomic force microscopy in Candida was conducted for the first time. Conclusion: These biocompatible C-QDs have promising potential as next-generation nanotrackers for in vitro and in vivo targeted cellular and live imaging, after functionalization with biomolecules and drugs. Scientists have used radiolabeled drugs and radioactive tracking agents for the imaging and study of drug resistance in microbial pathogens. But, these radiolabeled drugs or radiotrackers pose health hazards and environmental risks. However, such limitations can be overcome by designing nontoxic, environment-friendly, nanotechnology-based fluorescent imaging agents. This study demonstrates the development and application of cost-effective, nontoxic carbon-based quantum dots for imaging of drug-sensitive and -resistant microbial strains and transition to different morphological forms (yeast-to-hyphae transition) in fungal pathogens. The results demonstrated the suitability of carbon quantum dots as next-generation nano-based bioimaging/tracking agents for cellular imaging. The availability of such nontoxic fluorescent tracking agents is likely to offer promising solutions in therapeutics and diagnostics by providing insight into various mechanisms and functional links related to drug resistance, virulence and pathogenicity. [ABSTRACT FROM AUTHOR]

In recent years, bacterial infection has become one of the significant clinical challenges. The overuse or misuse of antibiotics increases the number of antibiotic‐resistant bacterial pathogens and causes enormous medical burdens with high morbidity and mortality. Several strategies have been adopted to tackle this; poly‐ionic liquids (PILs), a class of ionic liquids (ILs) systems demonstrating a broad spectrum of antimicrobial activities, have been widely used in biomedical applications. During polymerization, the charge density of the cations, molecular weight, and hydrophobic behavior can be regulated to accomplish more potent antibacterial efficacy with low cytotoxicity. However, inadequate literature is available highlighting the application of PIL‐based materials in biomedical applications. Keeping this in mind, the recent advances in PIL‐based biomaterials formed by conjugating PIL with natural and synthetic polymers as effective antimicrobial agents have been the focus area of this review. [ABSTRACT FROM AUTHOR]

The incorporation of bio-friendly nano-zeolite (NZ) into ultra-high molecular weight polyethylene (UHMWPE), renowned for its exceptional biocompatibility, presents an intriguing pathway for robust structural biomedical applications. This study aimed to investigate the influence of NZ integration on the tensile and impact properties of UHMWPE/NZ nanocomposites through experimental and morphological assessments. The morphology examinations primarily entailed particle distribution, clustering extent, and the primary toughening response induced by fillers under impact loading. Fourier transform infrared spectroscopy (FTIR) was utilized to investigate the bonding characteristics between NZ and UHMWPE within the nanocomposites. Moreover, differential scanning calorimetry (DSC) was employed to examine alterations in the crystalline structure of the nanocomposites, revealing an increase of up to 9% in crystallinity (Xc) following the incorporation of NZ. Tensile tests demonstrated significant improvements, with a 45% increase in tensile modulus and a 14% increment in strength upon the inclusion of NZ. Impact toughness consistently showed enhancements of up to 24%. The improved impact strength was attributed to the extensive partial particle-induced debonding and subsequent release of plastic constraints within the matrix. The micromechanisms responsible for nanoparticle-triggered toughening were further investigated using super-magnified images from impact-fractured SEM micrographs, and various impact toughening mechanisms were observed, classified, and discussed in the UHMWPE/NZ nanocomposites. Various analytical solutions were employed to predict the elastic modulus and tensile strength of nanocomposites. Subsequently, the results were compared to experimental data, and any discrepancies were thoroughly justified. Highlights • The mechanical traits of UHMWPE/nano-zeolite nanocomposites were explored. • Tensile and impact strength increased up to 14% and 24% with NZ addition. • Morphological inspections were conducted to assess filler-induced debonding. • Toughening mechanisms were assessed through super-magnified SEM micrographs. • Micromechanical models were used to predict the tensile modulus and strength. [ABSTRACT FROM AUTHOR]

Highlights: Naturally crosslinked carbonaceous liquid metal aqueous printable ink mediated by biopolymers. E-textile with conductivity, stability, wearability, and aesthetic characteristics. Multi-applications in health monitoring, pressure sensing, and energy harvesting. Achieving flexible electronics with comfort and durability comparable to traditional textiles is one of the ultimate pursuits of smart wearables. Ink printing is desirable for e-textile development using a simple and inexpensive process. However, fabricating high-performance atop textiles with good dispersity, stability, biocompatibility, and wearability for high-resolution, large-scale manufacturing, and practical applications has remained challenging. Here, water-based multi-walled carbon nanotubes (MWCNTs)-decorated liquid metal (LM) inks are proposed with carbonaceous gallium–indium micro-nanostructure. With the assistance of biopolymers, the sodium alginate-encapsulated LM droplets contain high carboxyl groups which non-covalently crosslink with silk sericin-mediated MWCNTs. E-textile can be prepared subsequently via printing technique and natural waterproof triboelectric coating, enabling good flexibility, hydrophilicity, breathability, wearability, biocompatibility, conductivity, stability, and excellent versatility, without any artificial chemicals. The obtained e-textile can be used in various applications with designable patterns and circuits. Multi-sensing applications of recognizing complex human motions, breathing, phonation, and pressure distribution are demonstrated with repeatable and reliable signals. Self-powered and energy-harvesting capabilities are also presented by driving electronic devices and lighting LEDs. As proof of concept, this work provides new opportunities in a scalable and sustainable way to develop novel wearable electronics and smart clothing for future commercial applications. [ABSTRACT FROM AUTHOR]

Cardiovascular disease (CVD) remains the leading cause of mortality worldwide. In particular, patients who suffer from ischemic heart disease (IHD) that is not amenable to surgical or percutaneous revascularization techniques have limited treatment options. Furthermore, after revascularization is successfully implemented, there are a number of pathophysiological changes to the myocardium, including but not limited to ischemia-reperfusion injury, necrosis, altered inflammation, tissue remodeling, and dyskinetic wall motion. Electrospinning, a nanofiber scaffold fabrication technique, has recently emerged as an attractive option as a potential therapeutic platform for the treatment of cardiovascular disease. Electrospun scaffolds made of biocompatible materials have the ability to mimic the native extracellular matrix and are compatible with drug delivery. These inherent properties, combined with ease of customization and a low cost of production, have made electrospun scaffolds an active area of research for the treatment of cardiovascular disease. In this review, we aim to discuss the current state of electrospinning from the fundamentals of scaffold creation to the current role of electrospun materials as both bioengineered extracellular matrices and drug delivery vehicles in the treatment of CVD, with a special emphasis on the potential clinical applications in myocardial ischemia. [ABSTRACT FROM AUTHOR]

Cancer is conventionally treated by chemotherapy, radiotherapy, or surgery. The urgent need to look for alternative therapeutic strategies reflects many loopholes. Developing a drug, however, is both time-consuming and expensive. Therefore, repurposing a licensed drug along with a means to take care of the limitations can become a very sustainable approach in cancer therapy. To further intensify these responses, nanotechnology would be useful to enhance the drug's delivery and retention while reducing toxicity. In this review, we explore the complicated association of cancer and drug repurposing and summarize recent advances in nanomaterial-based drug repurposing approaches. [ABSTRACT FROM AUTHOR]

Aim: The present research focused on development and optimization of ligand decorated theranostic nanocarrier encapsulating paclitaxel and carbon quantum dots (CQDs). Methods: CQDs were prepared by microwave-assisted pyrolysis and were characterized for particle size and fluorescence behavior. Ligand decorated zein nanoparticles, coloaded with paclitaxel and CQDs, were formulated using a one-step nanoprecipitation method and optimized for various process parameters. Results: Particle size for coated and uncoated nanoparticles was 90.16 ± 1.65 and 179.26 ± 3.61 nm, respectively, and entrapment efficiency was >80%. The circular dichroism spectroscopy showed zein retained its secondary structure and release study showed biphasic release behavior. Conclusion: The prepared theranostic nanocarrier showed optimal fluorescence and desired release behavior without altering the secondary structure of zein. [ABSTRACT FROM AUTHOR]

Polyhydroxybutyrate (PHB) is known for wide applications, biocompatibility, and degradability; however, it cannot be commercialized due to conventional recovery using solvents. The present study employed mechanical cell-disruption methods, such as Pestle and mortar, sonication, and glass bead vortexing, for solvent-free extraction of PHA from Bacillus sp. Different time intervals were set for grinding (5, 10, 15 min), sonicating (1, 3 and 5 min), and vortexing (2, 5 and 8 g glass beads with 5, 10 and 15 min each) hence studying their effect on cell lysis to release PHA. Tris buffer containing phenylmethyl sulfonyl fluoride (PMSF) (20 mM Tris–HCl, pH 8.0, 1 mM PMSF) was employed as a lysis buffer to study its action over Bacillus cells. Its presence was checked with the above methods in cell lysis. Sonicating cells for 5 min in the presence of lysis buffer achieved a maximum PHA yield of 45%. Cell lysis using lysis buffer yielded 35% PHA when vortexing with 5 g glass beads for 15 min. Grinding cells for 15 min showed a maximum yield of 34% but lacked a lysis buffer. The overall results indicated that the action of lysis buffer and physical extraction methods improved PHA yield by %. Therefore, the study sought to evaluate the feasibility of applying laboratory methods for cell disruption. These methods can showcase possible opportunities in large-scale applications. The polymer yield results were compared with standard sodium hypochlorite extraction. Confirmation of obtained polymers as polyhydroxy butyrate (PHB) was made through FTIR and 1HNMR characterization. [ABSTRACT FROM AUTHOR]

One aim of personalized medicine is to use continuous or on-demand monitoring of metabolites to adjust prescription dosages in real time. Surface-enhanced spatially offset Raman spectroscopy (SESORS) is an optical technique capable of detecting surface-enhanced Raman spectroscopy (SERS)-active targets under a barrier, which may enable frequent metabolite monitoring. Here we investigate how the intensity of the signal from SERS-active material varies spatially through tissue, both experimentally and in a computational model. Implant-sized, SERS-active hydrogel was placed under different thicknesses of contiguous tissue. Emission spectra were collected at the air-tissue boundary over a range of offsets from the excitation site. New features were added to the Monte Carlo light-tissue interaction model to modify the optical properties after inelastic scattering and to calculate the distribution of photons as they exit the model. The Raman signals were detectable through all barrier thicknesses, with strongest emission for the case of 0 mm offset between the excitation and detector. A steep decline in the signal intensities occurred for offsets greater than 2 mm. These results did not match published SORS work (where targets were much larger than an implant). However, the model and experimental results agree in showing the greatest intensities at 0 mm offset and a steep gradient in the intensities with increasing offset. Also, the model showed an increase in the number of photons when the new, longer wavelengths were used following the Stokes shift for scattering and the graphical display of the exiting photons was helpful in the determination and confirmation of the optimal offset. [ABSTRACT FROM AUTHOR]

Ceftriaxone sodium belongs to the third-generation cephalosporin group and is used intramuscular and intravenous route as a broad-spectrum antibiotic. This research aims to prepare biocompatible hydrogels for targeted delivery of ceftriaxone sodium by parental route. Different proportions of polymers (natural and synthetic) in the presence of cross-linker were synthesized by solvent casting method. Ceftriaxone sodium was loaded in hydrogels in different concentrations and its drug release behavior was evaluated along with swelling and biodegradation analysis. The characterization of hydrogel was done by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) to analyze surface morphology and functional groups involved in the formation of dextrin/Na-alginate/PVA hydrogels loaded with the drug. Thermogravimetric analysis (TGA) was confirmed by thermal stability and degradation pattern of loaded and unloaded hydrogels. The drug-loaded samples presented promising antimicrobial activity against S. aureus and P. multocida and their cytotoxic nature was also studied. Drug release analysis using simulated intestinal fluid (SIF) and phosphate buffer saline(PBS) for the circulatory system shows the consistent release of the drug. The findings unveiled the development of a biocompatible and innovative hydrogel, which has potential advantages for biomedical application, particularly in enhancing the therapeutic efficacy of ceftriaxone sodium drug.

Wound healing refers to the replacement of destroyed or damaged tissue of a living organism by newly produced tissue, and the time taken is known as wound regeneration time. Wound care is a major challenging biomedical field due to the delayed healing process or delayed wound regeneration time. The factors responsible for delayed wound healing are poor oxygen flow, less exposure to moisture, diseases such as diabetes and cancer, etc., Wound dressings that are formulated from biopolymers such as chitosan, chitin, and cellulose have properties such as biocompatibility (compatible with living systems and does not cause any immunological rejection), biodegradable, nontoxic with minimal side effects, anti-microbial, anti-inflammatory properties. Chitosan is obtained from scales of fish and shrimp. It contains highly reactive amine groups and sodium alginate, which is a polysaccharide produced from seaweed and bacteria and is biocompatible with living systems and biodegradable polysaccharides. This study is based on the development of sodium alginate crosslinked hydrogel and testing the properties of hydrogel with amoxycillin drug and water release property of the drug.

Arterial pulse waves contain a wealth of parameters indicative of cardiovascular disease. As such, monitoring them continuously and unobtrusively can provide health professionals with a steady stream of cardiovascular health indices, allowing for the development of efficient, individualized treatments and early cardiovascular disease diagnosis solutions. Blood pulsations in superficial arteries cause skin surface deformations, typically undetectable to the human eye; therefore, Microelectromechanical systems (MEMS) can be used to measure these deformations and thus create unobtrusive pulse wave monitoring devices. Miniaturized ultrathin and flexible Aluminium Nitride (AlN) piezoelectric MEMS are highly sensitive to minute mechanical deformations, making them suitable for detecting the skin deformations caused by cardiac events and consequently providing multiple biomarkers useful for monitoring cardiovascular health and assessing cardiovascular disease risk. Conventional wearable continuous pulse wave monitoring solutions are typically large and based on technologies limiting their versatility. Therefore, we propose the adoption of $29.5 ~\mu \text{m}$ -thick biocompatible, skin-conforming devices on piezoelectric AlN to create versatile, multipurpose arterial pulse wave monitoring devices. In our initial trials, the devices are placed over arteries along the wrist (radial artery), neck (carotid artery), and suprasternal notch (on the chest wall and close to the ascending aorta). We also leverage the mechano-acoustic properties of the device to detect heart muscle vibrations corresponding to heart sounds S1 and S2 from the suprasternal notch measurement site. Finally, we characterize the piezoelectric device outputs observed with the cardiac cycle events using synchronized electrocardiogram (ECG) reference signals and provide information on heart rate, breathing rate, and heart sounds. The extracted parameters strongly agree with reference values as illustrated by minimum Pearson correlation coefficients (r) of 0.81 for pulse rate and 0.95 for breathing rate.

Burns range in severity depending on the amount of area they cover on the body and how deeply they penetrate the skin and tissue beneath. Wound healing is an intricate and orchestrated process involving the interactions of various cell components to establish a provisional tissue and then remodel this while forming the mature replacement. Many types of polymers have been used for wound healing till date, which had benefits and disadvantages associated with it. The work here concerns towards effective wound healing process by employing the use of Musa paradisiaca Linn. commonly known as Banana, which had been used traditionally in India for dressings of wound and ulcers. The appropriate combination of the M. paradisiaca leaves and stem, along with the synthetic polymer, Polyethylene glycol was used, since it possess the properties of being biocompatible, in addition to being a good antimicrobial agent along with antioxidant properties. Characterization of the materials using FTIR provides the congruence of the presence of components that assist in effective wound healing. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are receiving increasing interest in biomedical applications. However, due to their large surface area, in physiological environments, they tend to interact with plasma proteins, inducing their agglomeration and ultimately resulting in a substantial efficiency decrease in diagnostic and therapeutic applications. To overcome such problems, NPs are typically coated with a layer of hydrophilic and biocompatible polymers, such as PEG chains. However, few examples exist in which this property could be systematically fine-tuned and combined with added properties, such as emission. Herein, we report a novel mussel-inspired catechol-based strategy to obtain biocompatible and multifunctional coatings, using a previously developed polymerization methodology based on the formation of disulfide bridges under mild oxidative conditions. Two families of NPs were selected as the proof of concept: mesoporous silica NPs (MSNPs), due to their stability and known applications, and magnetite NPs (Fe3O4 NPs), due to their small size (

Chronic wounds often result in multiple infections with various kinds of bacteria and uncontrolled wound exudate, resulting in several healthcare issues. Advanced medicated nanofibres prepared by electrospinning have gained much attention for their topical application on infected chronic wounds. The objective of this work is to enhance the critical variables of ciprofloxacin-loaded polycaprolactone-silk sericin (PCL/SS-PVA-CIP) nanofibre production via the process of electrospinning. To examine the antibacterial effectiveness of PCL/SS-PVA-CIP nanocomposites, the material was tested against P. aeruginosa and S. aureus. The combination of PCL/SS-PVA-CIP exhibited potent inhibitory properties, with the most effective concentrations of ciprofloxacin (CIP) being 3 μg/g and 7.0 μg/g for each bacterium, respectively. The biocompatibility was evaluated by conducting cell reduction and proliferation studies using the human epidermal keratinocyte (HaCaT) cells and human gingival fibroblasts (HGFs) in vitro cell lines. The PCL/SS-PVA-CIP showed good cell compatibility with HaCaT and HGF cells, with effective proliferation even at antibiotic doses of up to 7.0 μg/g. The drug release effectiveness of the nanocomposites was assessed at various concentrations of CIP, resulting in a maximum cumulative release of 76.5% and 74.4% after 72 h for CIP concentrations of 3 μg/g and 7 μg/g, respectively. In summary, our study emphasizes the possibility of combining silk sericin (SS) and polycaprolactone (PCL) loading with CIP nanocomposite for wound management.

BackgroundThere is limited "real-world" evidence examining treatment modalities and outcomes in patients with symptomatic peripheral arterial disease undergoing endovascular treatment of femoropopliteal (FP) in-stent restenosis (ISR).Materials and methodsWe compared outcomes in 2,895 patients from the XLPAD registry (NCT01904851) between 2006 and 2019 treated for FP ISR (n = 347) and non-ISR (n = 2,548) lesions. Primary endpoint included major adverse limb events (MALE) at 1 year, a composite of all-cause death, target limb repeat revascularization, or major amputation.ResultsISR patients were more frequently on antiplatelet (94.5% vs 89.4%, p=0.007) and statin (68.9% vs 60.3%, p=0.003) therapies. Lesion length was similar (ISR: 145 ± 99 mm vs. non-ISR: 142 ± 99 mm, p=0.55). Fewer treated ISR lesions were chronic total occlusions (47.3% vs. 53.7%, p=0.02) and severely calcified (22.4% vs. 44.7%, p < 0.001). Atherectomy (63.5% vs. 45.0%, p < 0.001) and drug-coated balloons (DCB; 4.7% vs. 1.7%, p < 0.001) were more frequently used in ISR lesions. The distal embolization rate was higher in ISR lesions (2.4% vs. 0.9%, p=0.02). Repeat revascularization (21.5% vs. 16.7%, p=0.04; Figure) was higher and freedom from MALE at 1 year was significantly lower (87% vs. 92.5%, p < 0.001) in the ISR group.ConclusionAtherectomy and DCB are more frequently used to treat FP ISR lesions. Patients with FP ISR have more intraprocedural distal embolization, higher repeat revascularization procedures, and lower freedom from MALE at 1 year.

A fine control over different dimensional scales is a challenging target for material science since it could grant control over many properties of the final material. In this study, we developed a multivariable additive manufacturing process, direct ink write printing, to control different architectural features from the nano- to the millimeter scale during extrusion. Chitin-based gel fibers with a water content of around 1500% were obtained extruding a polymeric solution of chitin into a counter solvent, water, inducing instant solidification of the material. A certain degree of fibrillar alignment was achieved basing on the shear stress induced by the nozzle. In this study we took into account a single variable, the nozzles internal diameter (NID). In fact, a positive correlation between NID, fibril alignment, and mechanical resistance was observed. A negative correlation with NID was observed with porosity, exposed surface, and lightly with water content. No correlation was observed with maximum elongation (~50%), and the scaffolds excellent biocompatibility, which appeared unaltered. Overall, a single variable allowed a customization of different material features, which could be further tuned, adding control over other aspects of the synthetic process. Moreover, this manufacturing could be potentially applied to any polymer.

The electronic device, with its biocompatibility, biodegradability, and ease of fabrication process, shows great potential to embed into health monitoring and hardware data security systems. Herein, polyvinylpyrrolidone (PVP) biopolymer is presented as an active layer, electrochemically active magnesium (Mg) as a metal electrode, and chitosan‐based substrate (CHS) to fabricate biocompatible and biodegradable physically transient neuromorphic device (W/Mg/PVP/Mg/CHS). The I–V curve of device is non‐volatile bipolar in nature and shows a unique compliance‐induced multilevel RESET‐dependent‐SET behavior while sweeping the compliance current from a few microamperes to milliamperes. Non‐volatile and stable switching properties are demonstrated with a long endurance test (100 sweeps) and retention time of over 104 s. The physically transient memristor (PTM) has remarkably high dynamic RON/ROFF (ON/OFF state resistance) ratio (106 Ω), and when placed in deionized (DI) water, the device is observed to completely dissolve within 10 min. The pulse transient measurements demonstrate the neuromorphic computation capabilities of the device in the form of excitatory post synaptic current (EPSC), potentiation, depression, and learning behavior, which resemble the biological function of neurons. The results demonstrate the potential of W/Mg/PVP/Mg/CHS device for use in future healthcare and physically transient electronics. [ABSTRACT FROM AUTHOR]

In this study, we have stated the green biosynthesis of gold nanoparticles (AuNPs) by utilizing the extract of Monstera deliciosa leaves (MDL) as a reducing agent. Biosynthesized flat, thin, and single-crystalline gold nanotriangles obtained through centrifugation are then analyzed by different characterization techniques. The UV − visible absorption spectra of AuNPs exhibited maxima bands in the range of 500–590 nm, indicating a characteristic of AuNPs. XRD analysis revealed the formation of the (111)-oriented face-centered cubic (FCC) phase of AuNPs. ATR-IR spectra showed signatures of stretching vibrations of O–H, C-H, C=C, C=O, C–O, and C-N, accompanied by CH3 rocking vibrations present in functional groups of biomolecules. FESEM images confirmed spherical nanoparticles with an average diameter in the range of 53–66 nm and predominantly triangular morphology of synthesized AuNPs within the size range of 420–800 nm. NMR, GC–MS, and HR–MS studies showed the presence of different biomolecules, including phenols, flavonoids, and antioxidants in MDL extracts, which play a crucial role of both, reducing as well as stabilizing and capping agents to form stable AuNPs by a bottom-up approach. They were then investigated for their antibacterial assay against Gram-positive (S. aureus, B. subtilis) and Gram-negative (E. coli, P. aeruginosa) microorganisms, along with testing of antifungal potential against various fungi (Penicillium sp., Aspergillus flavus, Fusarium oxysporum, Rhizoctonia solani) using the well diffusion method. Here, biosynthesized AuNPs showed non-antimicrobial properties against all four used bacteria and fungi, showing their suitability as a contender for biomedical applications in drug delivery ascribed to their inert and biocompatible nature. [ABSTRACT FROM AUTHOR]

Niacin plays a significant role in the therapy and management of mixed dyslipidemia. Nevertheless, its administration in raw form is contraindicated due to potential adverse effects including hepatotoxicity and cutaneous flushing. Prostaglandin D2 (PGD2) plays a crucial role in the signaling cascade of niacin-induced flushing. To address the potential adverse reactions linked to niacin therapy, we developed a niacin-loaded lyotropic liquid crystal nanoparticle (NLCS) crafted explicitly for the oral administration of niacin. NLCSs were produced by disrupting the cubic gel of glyceryl monostearate (GMS). The nanoparticles demonstrated notable drug-loading capabilities with a size of approximately 255 ± 31.6 nm. Furthermore, NLCS displayed sustained release behavior, indicating their potential for controlled and prolonged drug delivery. Efficient encapsulation and minimal interaction between niacin and other excipients were evidenced through Fourier transform infrared and X-ray diffraction studies, establishing their high stability. In vitro studies suggested that the nanoparticles had good antioxidant activity, swelling behavior, and biocompatibility. Additionally, compared to raw niacin, NLCS showed a higher in vivo therapeutic efficacy, less hepatotoxicity, a more refined lipid profile, and an improved complete blood count (CBC) profile. In addition, it was shown that animals treated with NLCS had lower PGD2 levels than those treated with raw niacin. In conclusion, our study highlights the potential of NLCS as a promising strategy to alleviate the side effects linked to the direct ingestion of pure niacin. These nanoparticles offer a solution to flushing-like symptoms and hepatotoxicity, positioning them as a viable therapeutic option for managing dyslipidemia. [ABSTRACT FROM AUTHOR]

Herein, cellulose as a natural biomass along with urea was acid-charred to synthesize nitrogen-doped carbon nanoflakes (N-CNF). The as-prepared N-CNF was used to rapidly remove the effluent of agricultural waste containing an Imidacloprid (IMD) insecticide. The adsorption data fit well to nonlinearly in the Sips adsorption model, which is a mixed Langmuir-Freundlich model with an adsorption capacity of ∼104.9 mg g–1. The adsorption follows pseudo-second-order kinetics linearly and nonlinearly, and thermodynamic parameters reveal that the adsorption process was spontaneous and endothermic. The effect of pH and the interference of ions was also checked. Further, spiking of IMD in different soil, lake, and tap wastewater samples was also done to enhance the practical applicability of removing IMD by N-CNF. The antibacterial properties of N-CNF were checked on both Gram-negative and Gram-positive bacterial strains as Escherichia coli and Bacillus subtilus, respectively, where they showed nontoxic behavior up to the concentration of 2 mg mL–1. [ABSTRACT FROM AUTHOR]

In this study, the cyclic trimer of hexachlorocyclotriphosphazene (HCCP) was used as the starting material for the thermal ring opening polymerization (T-ROP) method, which was followed by a macromolecular substitution reaction to create three Polyphosphazene derivatives with aromatic side groups. FTIR, 1HNMR, 31PNMR, DSC, elemental analysis, and gel permeation chromatography were used to characterise the synthesised polymer (GPC). The hydrolytic breakdown using shaker bath was studied at various pH at 37 °C for 42 days. Significant degradation products were noticed at different pH values. Studies on degradation revealed that synthetic polymers offer a wide range of potential uses in the biological field. [ABSTRACT FROM AUTHOR]

Purposely designed nano-scale gold for diverse biomedical applications like therapeutics and diagnostics is gaining scientific impetus. These colloidal particles vary in dimension between 10 and 100 nm. They can be tailored to arrive at unique characteristics related to size, morphology and surface modalities linked to intended application. Additionally, biocompatibility is a major criterion for the clinical use of these nano-range products. Several established laboratory methods exist to synthesize nano-gold in small scale whereas few methods explore their transformation into industrial scale. Large-scale methods are limited and needs significant supply of newer entrants to overcome the problems and to cater the diverse variety of nano-scale gold which are currently under pre-clinical and clinical investigations. Although some gold nanoparticles have entered the market still there are several lacunas in up-scaling of these materials and confirming their safety for biomedical applications. As a result, industries are inclined to analyze the scale up feasibilities and commercialization of all such products. This review for the first time provides an updated analysis of the lab-scale and large-scale synthesis routes to arrive at nano-dimensional gold with a spot-light on the challenges involved in the process. [ABSTRACT FROM AUTHOR]

Along with the rapid and extensive advancements in the 3D printing field, a diverse range of uses for 3D printing have appeared in the spectrum of medical applications. Vat photopolymerization (VPP) stands out as one of the most extensively researched methods of 3D printing, with its main advantages being a high printing speed and the ability to produce high-resolution structures. A major challenge in using VPP 3D-printed materials in medicine is the general incompatibility of standard VPP resin mixtures with the requirements of biocompatibility and biofunctionality. Instead of developing completely new materials, an alternate approach to solving this problem involves adapting existing biomaterials. These materials are incompatible with VPP 3D printing in their pure form but can be adapted to the VPP chemistry and general process through the use of innovative mixtures and the addition of specific pre- and post-printing steps. This review's primary objective is to highlight biofunctional and biocompatible materials that have been adapted to VPP. We present and compare the suitability of these adapted materials to different medical applications and propose other biomaterials that could be further adapted to the VPP 3D printing process in order to fulfill patient-specific medical requirements. [ABSTRACT FROM AUTHOR]

Nanogels, nanosized water-soluble physically and/or chemically cross-linked polymeric networks, have been widely prepared, characterized and studied in recent years due to their attractive properties, especially in biomedical applications as delivery vehicle for therapeutic and diagnostic purposes. Here, we present a facile new synthetic strategy to prepare ultra-small amphiphilic nanogels with tunable properties from a bioactive natural material (curcumin, with its well-known functionalities and health promoting activities) and a biocompatible maleic anhydride-based polymer. Our approach is based on a combination of chemical cross-linking, hydrophobic interaction and self-assembly. The nanogels were investigated for their physicochemical properties and colloidal stability under different pH values and salt concentrations as well as the in vitro cytotoxicity. The results indicated negative surface charge (as indicated by gel electrophoresis and laser Doppler anemometry with a zeta potential of − 60 mV) nanogels of small sizes (dh = 5.6 nm) with high colloidal stability at a wide range of pH values and NaCl concentrations. Additionally, the nanogels were not toxic up to concentration 100 μg/mL for BEAS-2B and A549 cells. The relatively facile preparation, high colloidal stability, ultra-small size and possible surface modification, functionalization and/or bioconjugation makes the obtained nanogels of great importance, especially in sensing and biomedical applications. [ABSTRACT FROM AUTHOR]

We have investigated, for the first time, the hyperthermia properties, antibacterial, anticancer and antioxidant activities, as well as their toxicity, of Mn 0.25 Mg 0.25 Co 0.5 Fe 2 O 4 nanoparticles synthesized by the sol-gel auto-combustion method. X-ray diffraction results revealed a pure phase and good crystallinity of the synthesized. In addition, the Fourier transform infrared (FTIR) spectrum confirmed the formation of the crystallographic sites of the synthesized structure. In terms of morphology, scanning electron microscopy (SEM) showed that the nanoparticles were agglomerated. In addition, transmission electron microscopy (TEM) revealed that the nanoparticles had a cubic shape and a nanometric size of around 32 nm. Energy-dispersive X-ray spectroscopy (EDS) confirmed the chemical composition of the nanoparticles. With regard to magnetic properties, magnetic measurements showed almost ferrimagnetic behavior, with a saturation magnetization of 38.90 emu/g at room temperature. Hyperthermia measurements revealed relatively good heating efficiencies, with SAR value of 33W/g, good temperature rise and short time to reach magnetic hyperthermia temperature 42 °C (8 min). For biological activities the nanoparticles showed an excellent capacity to neutralize free radicals, eliminating 97% of DPPH and 95% of hydrogen peroxide. The dose of 40 mg/kg of the nanoparticles caused significant alterations in hematological and biochemical profiles. The material showed a significant effect on various bacterial strains, including Staphylococcus aureus and Bacillus subtilis. The synthesized nanoparticles also showed significant activity against various cell lines, including MCF-7 and HeLa. These results strongly suggest the promising utilization of Mn 0.25 Mg 0.25 Co 0.5 Fe 2 O 4 , in many applications as a potential candidate for magnetic-mediated hyperthermia. [ABSTRACT FROM AUTHOR]

Wearable electronics have impacted many aspects of human life including health monitoring, disease diagnosis, and human‐machine interfacing. However, the rapid development also accelerates the generation of electronic waste (e‐waste), which is threatening the health of ecological systems. Accordingly, high‐performance biodegradable materials suitable for transient electronics are highly demanded and challenging. In this work, a fully biodegradable and biocompatible ionotronic skin is designed based on double‐network natural polyelectrolytes derivatives. It consists of carboxylated chitosan (CCS) and sulfobetaine methacrylate (SBMA) polymerized in glycerol and water followed by cross‐linking with hydrogen bonds and electrostatic attraction (namely SBMAX‐CCSY‐Glyz). By macromolecular engineering, the ionotronic skin exhibits high ionic conductivity, good compliance with skin, as well as complete degradability, which is capable of transient measurement of electrophysiology. Applied on the sciatic nerve of bullfrog, it can accurately record action potentials and fully degrade in only 3 days without any residue. Such biodegradable and biocompatible ionotronic skin will shed light on the design of ionotronic materials for future transient electronics. [ABSTRACT FROM AUTHOR]