Nanotechnology has attracted great attention from researchers in modern science because nanomaterials have innovative and superior physical, chemical, and biological properties, and they can be altered and modified accordingly. As particles get smaller, their surface area increases compared to their volume. Electrospinning is one of the advanced techniques to produce ultrathin nanofibers and membranes, and it is one of the best ways to create continuous nanomaterials with variable biological, chemical, and physical properties. The produced fibers can be utilized in various domains such as wound dressing, drug release, enzyme immobilization, etc. This review examines the biomedical nanofibers/membranes produced by electrospinning techniques to investigate the effects of process parameters (e.g., solution characteristics, applied voltage, and ambient conditions) on nanofiber characteristics (physical, chemical, and mechanical properties). The solution parameters like (i) optimum concentration, (ii) higher molecular weight, and (iii) higher conductivity produce uniform nanofibers, smoother nanofibers, and a smaller and more uniform fiber diameter, respectively. In addition, process parameters such as (i) higher voltage and (ii) slower flow rate produce more polymer ejection from the nozzle and enhance the smoother fiber production, respectively. The optimum tip-to-collector distance is considered to be 13–15 cm. The ambient conditions such as (i) higher humidity and (ii) higher temperature produce thicker and thinner nanofibers, respectively. The controlled parameters through optimization process determine the size and quality of the fibers. The effects of each parameter are discussed in this review. The applications of nanofibers are also discussed.

Hevea brasiliensis (HB) flower particulates were filled high‐density poly ethylene (HDPE) composite was molded through a vertical injection molding process. The molded composite specimens were carried out X‐ray powder diffraction analysis and found the HB filler crystal size of 12.63 nm. The morphology of the HB/HDPE composite was analyzed through field emission scanning electron microscope and the presence of different elements was found through energy dispersive X‐ray. The HB/HDPE composite was carried out thermo gravimetric analysis, differential scanning calorimetric, and found its melting point and its degradation. The HB/HDPE composite was carried out and found its mechanical properties. The observed result suggests that the newly developed composites could be used for low‐strength applications.

This paper presents the formulation, characterization, and in vitro studies of polymer composite material impregnated with naturally derived hydroxyapatite (HA) particulates for biomedical implant applications. Laevistrombus canarium (LC) seashells (SS) were collected, washed and cleaned, sun-dried for 24 h, and ground into powder particulates. The SS particulates of different weight percentages (0, 10, 20, 30, 40, 50 wt%)-loaded high-density polyethylene (HDPE) composites were fabricated by compression molding for comparative in vitro assessment. A temperature-controlled compression molding technique was used with the operating pressure of 2 to 3 bars for particulate retention in the HDPE matrix during molding. The HDPE/LC composite was fabricated and characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX), differential scanning calorimetry (DSC), and TGA. Mechanical properties such as tensile, compression, flexural, hardness, and also surface roughness were tested as per ASTM standards. Mass degradation and thermal stability of the HDPE/LC composite were evaluated at different temperatures ranging from 10 to 700 °C using thermogravimetric analysis (TGA). The maximum tensile strength was found to be 27 ± 0.5 MPa for 30 wt% HDPE/LC composite. The thermal energy absorbed during endothermic processes was recorded as 71.24 J/g and the peak melting temperature (Tm) was found to be 128.4 °C for the same 30 wt% of HDPE/LC composite specimen. Excellent cell viability was observed during the in vitro biocompatibility study for EtO-sterilized 30 wt% of HDPE/LC composite specimen, except for a report of mild cytotoxicity in the case of higher concentration (50 µL) of the MG-63 cell line. The results demonstrate the potential of the fabricated composite as a suitable biomaterial for medical implant applications.

The emergence of smart materials (stimulus-responsive materials) and cells enables 4D printing to enhance printed structures dynamically. By undergoing controlled morphological changes, engineered tissues may be made using these dynamic scaffolds. This article provides an overview of the use of stimuli-responsive biomaterials in tissue engineering and several 4D printing methodologies based on the functional change of printed objects. This review also goes through the existing and future prospects for using 4D printing in bone tissue engineering and the limitations in this field. Using a variety of stimuli-responsive biomaterials and 4D printing techniques, the form or function of these objects might evolve. These novel technologies have the potential to meet unmet medical needs, as shown by a recent review that summarised the use of 4D printing in bone tissue engineering. This current review is about the potential of this cutting-edge technology for tissue engineering in the biomedical area by delving further into the ongoing conversations regarding future issues and perspectives.