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Abstract Cardiovascular diseases are the leading cause of mortality which primarily occurs due to the blood vessel obstruction or narrowing. Surgical procedures such as, coronary artery and peripheral artery bypass grafting frequently require vascular grafts for long‐term revascularization. However, using autogenous vessels, such as the internal thoracic artery and saphenous vein, especially for vessels with diameters less than 6 mm, are associated with number of concerns due to limited availability, invasive retrieval procedures, and aptness. To overcome these limitations, the development of tissue‐engineered vascular grafts (TEVGs) is in continuous thrust. This review comprehensively provides the potentiality of a range of artificial and naturally occurring biopolymers and their fabrication techniques, cell sources and seeding techniques to realize the state‐of‐the‐art TEVGs. Moreover, this review article presents a synopsis of insights obtained from a variety of in vitro and in vivo studies, including human clinical trials. It underscores the need for further exploration into key areas such as optimal cell sources, seeding techniques, mechanical properties, hemodynamics, graft integration, the impact of patient conditions, optimum burst pressure, sufficient suture strength, hydrophilicity, biodegradability, and related factors. In summary, the review offers insights into the current strategies, challenges, and future perspectives of TEVG.

This study aimed to investigate the possibility of enhancing the functionality of Quarg-type cheese by adding Arjuna bark powder in encapsulated form. Arjuna tree bark powder was extracted via ethanolic cold maceration. The encapsulated powder was made using Maltodextrin and Sodium alginate wall material solution and had encapsulating efficiency of 42 ± 4.2%. Response Surface Methodology (RSM) was applied to conduct optimization, and subsequent trials were thoroughly investigated to assess their Physico-chemical, sensory, textural, and desirable attributes. The recommended levels of variables as suggested by the Response Surface Methodology (RSM) encompassed 3% of encapsulated Arjuna herb powder and 4% of honey. The conducted analysis has demonstrated that the inclusion of these variables has resulted in a notable improvement in the functionality of quarg-type cheese. Specifically, these variables have contributed to the enhancement of its antioxidant properties, sensory characteristics, rheological attributes, and textural qualities. The encapsulation of the Arjuna herb effectively concealed its astringent taste in the optimized product. Furthermore, the inclusion of honey not only improved the product's acceptability but also strengthened its antioxidative properties.

Objectives: The objective of this study is to evaluate the ability of the bioactive glass (BAG)-Bonds to inhibit the demineralization surrounding the orthodontic brackets when being exposed to an in vitro caries challenge and also simultaneously evaluate the physical and mechanical properties in order to be accepted as an orthodontic bonding agent. Materials and Methods: Preparation of mesoporous bioactive glass (MBG) used an improved sol-gel method, combining with sacrificial liquid template to MBGs with controllable particle size. Tetraethyl orthosilicate, triethyl phosphate, calcium nitrate tetrahydrate, ethanol absolute, ethyl acetate, hexadecyltrimethylammonium bromide, deionized water, and ammonium hydroxide were used. The microstructure was analyzed using a field emission gun-based scanning electron microscope (SEM). The debonding and adhesion characteristics were analyzed using an Instron Universal Testing Machine. Results: SEM analysis shows that the prepared MBG particles possess spherical morphology with generally uniform size. Novel orthodontic bonding material (BG) provides adequate mechanical and physical properties in order to be accepted as an orthodontic bonding agent since its bond strength both at the time of bonding and after 6 months in simulated salivary conditions is significantly higher than conventional bonding resin (TBXT). The bond strength was also evaluated both initially at the time of bonding as well as 6 months after being kept in simulated salivary conditions. Conclusion: These novel adhesives result in reduced demineralization surrounding orthodontic brackets and possess optimal physical and mechanical properties to be accepted as an orthodontic adhesive.

Abstract Natural oil‐based polyurethanes are prepared through solvent‐less and easily processable approach for adhesive applications. The polyurethane is optimized through varying the volume fractions of the precursors which was then confirmed through the different analyses to achieve the better combination for composite formation with graphene. The graphene‐polyurethane composites are processed in a simple hand mixing process with different graphene loadings and the role of the addition of graphene is studied using different analyses. The addition of graphene and the interaction with the polymer is well established through structural and thermal studies. The increase in the mechanical property with the addition of graphene to adequate amount at room temperature confirms better interfacial interaction with the polymer. The maximum peel strength obtained for the PU is around 1.05 N/mm, which supports the applicability of the prepared material for adhesive‐based applications.

Abstract 3D bioprinting or additive manufacturing is an emerging innovative technology revolutionizing the field of biomedical applications by combining engineering, manufacturing, art, education, and medicine. This process involved incorporating the cells with biocompatible materials to design the required tissue or organ model in situ for various in vivo applications. Conventional 3D printing is involved in constructing the model without incorporating any living components, thereby limiting its use in several recent biological applications. However, this uses additional biological complexities, including material choice, cell types, and their growth and differentiation factors. This state‐of‐the‐art technology consciously summarizes different methods used in bioprinting and their importance and setbacks. It also elaborates on the concept of bioinks and their utility. Biomedical applications such as cancer therapy, tissue engineering, bone regeneration, and wound healing involving 3D printing have gained much attention in recent years. This article aims to provide a comprehensive review of all the aspects associated with 3D bioprinting, from material selection, technology, and fabrication to applications in the biomedical fields. Attempts have been made to highlight each element in detail, along with the associated available reports from recent literature. This review focuses on providing a single platform for cancer and tissue engineering applications associated with 3D bioprinting in the biomedical field.

Abstract The higher prevalence of cancer is related to high rates of mortality and morbidity worldwide. By virtue of the properties of matter at the nanoscale, nanomedicine is proven to be a powerful tool to develop innovative drug carriers with greater efficacies and fewer side effects than conventional therapies. In this review, different nanocarriers for controlled drug release and their routes of administration have been discussed in detail, especially for cancer treatment. Special emphasis has been given on the design of drug delivery vehicles for sustained release and specific application methods for targeted delivery to the affected areas. Different polymeric vehicles designed for the delivery of chemotherapeutics have been discussed, including graft copolymers, liposomes, hydrogels, dendrimers, micelles, and nanoparticles. Furthermore, the effect of dimensional properties on chemotherapy is vividly described. Another integral section of the review focuses on the modes of administration of nanomedicines and emerging therapies, such as photothermal, photodynamic, immunotherapy, chemodynamic, and gas therapy, for cancer treatment. The properties, therapeutic value, advantages, and limitations of these nanomedicines are highlighted, with a focus on their increased performance versus conventional molecular anticancer therapies.

Abstract Novel biocompatible and brush copolymers have been developed for cancer treatment using its controlled drug-release potential. Polyurethane graft on linear dextrin has been synthesized to control the hydrophilic–hydrophobic balance for regulated drug delivery. The properties of the graft copolymers have been tuned through graft density. The prepared grafts are thermally stable and mechanically strong. An injectable hydrogel has been developed by embedding the drug-loaded brush copolymers in methyl cellulose to better control the release for a prolonged period, importantly by keeping the drug release at a constant rate. Cellular studies indicate the biocompatible nature of the brush copolymers whose controlled and slow release of drug exhibit significant cytotoxic effects on cancer cells. Endocytosis of drug tagged contrast agent indicates greater transport of biologically active material inside cell as observed through cellular uptake studies. In vivo studies on melanoma mice exhibit the real efficacy of the controlled drug release from the injectable hydrogel with significant melanoma suppression without any side effects as opposed to severe toxic effects observed in conventional chemotherapy. Special application method of drug-loaded hydrogel just beneath the tumor makes this system incredibly effective through confinement. Thus, brush copolymer injectable hydrogel is a promising vehicle for control release of drug for cancer treatment in future.

Abstract Passive radiative cooling is an emerging field and needs further development of material. Hence, the computational approach needs to establish for effective metamaterial design before fabrication. The finite difference time domain (FDTD) method is a promising numerical strategy to study electromagnetic interaction with the material. Here, we simulate using the FDTD method and report the behavior of various nanoparticles (SiO2, TiO2, Si3N4) and void dispersed polymers for the solar and thermal infrared spectrums. We propose the algorithm to simulate the surface emissive properties of various material nanostructures in both solar and thermal infrared spectrums, followed by cooling performance estimation. It is indeed found out that staggered and randomly distributed nanoparticle reflects efficiently in the solar radiation spectrum, become highly reflective for thin slab and emits efficiently in the atmospheric window (8–13 µm) over the parallel arrangement with slight variation. Higher slab thickness and concentration yield better reflectivity in the solar spectrum. SiO2-nanopores in a polymer, Si3N4 and TiO2 with/without voids in polymer efficiently achieve above 97% reflection in the solar spectrum and exhibits substrate independent radiative cooling properties. SiO2 and polymer combination alone is unable to reflect as desired in the solar spectrum and need a highly reflective substrate like silver.

Bio-waste orange peel with poly(vinylidene fluoride) hybrids have been developed as an efficient energy harvester. Bio-wastes in huge amount cause landfills and environmental pollution. An effort in the direction of using bio-waste will be beneficial in many ways. Orange peel, a bio-waste, is mainly composed of cellulose and different proteins that are responsible for its piezoelectric effect. The hybrid exhibits significant piezoelectric properties arising through induced piezoelectricity in the polymer matrix by the smaller dimension orange peel powder as filler causing an electroactive phase of ∼70% in the hybrid. Integrated device has been fabricated for energy harvesting using the hybrid material, without conventional high voltage poling, which displays very high open circuit voltage of ∼90 V and power of 135 μW/cm2 using finger tapping. The hybrid nanogenerator is proficient in light up the LEDs from the movement of sliding door and from any human body movements like bending, twisting and walking etc. The underlying mechanism of enhanced piezoelectricity in the hybrid is revealed through structure, morphology and thermal studies of the hybrid. Thus, the piezoelectric energy harvester prepared from the bio-waste might be one of the solutions to utilize the bio-waste.

With the depletion of the conventional energy sources, measures are being taken to create an alternate energy sources for the future. Energy harvesting from different sources are one of the better steps taken in this direction. Mechanical energy harvesting from the waste mechanical source is gaining profound investigation. Here, a nanohybrid of poly(vinylidene fluoride) and lead zirconia titanate (PZT) is prepared through solution route for energy harvesting applications. PZT is synthesized using solid state route and its concentration was varied in the nanohybrid to get the best properties from the hybrid. Structural and morphological aspects of the nanohybrid have been explored for their suitable application. Device has been fabricated using the nanohybrid to convert the waste mechanical energy from various human motions to the useful electrical energy. The device is able to generate a maximum output voltage of 55 V and a power density of 36 μWcm−2. The device is able to produce voltage output from different human motions such as finger tapping, feet tapping and bending. The mechanism of charge conversion is also discussed which explains the generation of such a high electrical output from waste mechanical source.

Chemical modification of dextrin with polyurethane as a graft has been synthesized for controlled drug release for longer time period by maintaining the hydrophobic–hydrophilic balance. Estimation of the degree of grafting is visualized from the integrated peak area in the NMR spectra. Particle nature of dextrin is converted into strip like morphology in polyurethane graft dextrin copolymers as obvious from atomic force microscopy. Drug release study of graft copolymers through in vitro studies indicates sustained drug release behavior as compared to pristine dextrin and specific interactions between polymer and drug have been verified through spectroscopic techniques. Biocompatibility of the graft copolymers has been revealed using cellular studies on cancerous HeLa cells through MTT assay and cell adhesion. Further, the cytotoxicity or the cell killing efficiency has been demonstrated resulting in significant cell mortality using the developed graft copolymers.

Poly(vinylidene fluoride) (PVDF)/organically modified nanoclay composites using different amount of nanoclay have been prepared through solution route. The structural changes are determined through X-ray diffraction and Fourier transform infrared spectroscopy studies, which show the transformation from α to β-phase crystallization in presence of nanoclay. Polarised optical microscopic images show the changes of spherulite pattern into mesh like pattern in presence of nanoclay. Modulus of PVDF-nanocomposite increase with increasing the nanoclay content up to 4 wt.% and then slightly decreases under uniaxial tension and the improvement in mechanical responses are fitted with theoretical models. Tribological behaviour of PVDF nanocomposites is evaluated and found that nanoclay content upto 4 wt.% is effective in decreasing the wear and coefficient of friction of PVDF. Similarly, hardness of the nanocomposites also increases for clay content upto 4 wt.%. The nanoclay is working as reinforcing agent for PVDF and is improving its mechanical and frictional properties. Keywords: PVDF, Wear, Hardness, Morphology

Polymer ceramic composites are widely used for embedded capacitor application. In the present work PVDF has been used as a matrix and CCTO and LaCCTO have been used as reinforcement. Extrusion process has been used for the synthesis of composites. X-ray diffraction (XRD) patterns confirm the formation of single phase CCTO, and LaCCTO in its pure as well as composite state. It is found that La doping in CCTO considerably increases the dielectric constant and reduces the dielectric loss. A similar trend is observed in the composites with the increasing content of CCTO and LaCCTO.