Showing papers by "T. M. Sridhar published in 2021"

Nanohydroxyapatite-doped polycaprolactone-based nanoscaffolds as a viable drug delivery agent in bone tissue engineering

Abstract: In bone tissue engineering research, nanohydroxyapatite (n-HAp) has been recently gaining a lot of interest because of its excellent functional properties such as improvement in the formation of neo-tissue. In this study, the composite nanoscaffolds of n-HAp (0.1–0.5%)-doped polycaprolactone (PCL) (10%) were engineered by electrospinning as a drug delivery system and bone tissue growth. The cell proliferation activities of the prepared composite nanoscaffolds were examined in vitro using osteoblast cells like (MG-63) (Passage 10) cell line. The electrospun PCL/n-HAp nanoscaffolds were subjected to the drug delivery studies using a bone infection antibiotic cephalexin drug and the antibacterial study of the composite was carried out using Escherichia coli bacteria. These results revealed that the mechanical strength (13.25 ± 0.3536) increased and the fiber diameter decreased (100 nm) at the optimized n-HAp (0.4%) concentration, the maximum drug (68%) loading capacity of the electrospun nanofiber PCL/n-HAp takes place at 48 h and the maximum drug release was found to be 78% at 48 h. These novel nanohydroxyapatite-doped polycaprolactone (PCL/n-HAp) scaffolds show promising applications as a drug delivery system using cephalexin and this would also be a potential biomaterial for enhancing bone tissue growth.

Investigations on caesium-incorporated rubidium tin chloride-defect perovskite nanomaterial as highly efficient ultraviolet photocatalysts

Abstract: Recently perovskites-based inorganic compounds have been researched incredibly for their photocatalytic applications. In this work, rubidium tin chloride [Rb2SnCl6] and caesium-incorporated rubidium [(RbXCs1-X)2SnCl6]-defect perovskites were synthesized for photocatalytic applications. This material is very useful for the degradation of dyes under UV irradiation among other photocatalysts, because of its superior properties such as nontoxicity, low cost, simple preparation methods and long-term thermal stability. The crystal structure, morphology and elemental composition of synthesized defect perovskite materials have been analysed using XRD, FESEM and EDAX mapping analysis. The UV studies reveal that the band-gap values were tuned (from 2.71 eV in Rb2SnCl6 to 3.78 eV in (Rb0.5Cs0.5)2SnCl6), resulting in a blue shift of the PL emission peak (from 458 to 328 nm) due to the incorporation of caesium in rubidium site. The thermal stability of (Rb0.5Cs0.5)2SnCl6 is enhanced over other synthesized defect perovskite materials because 76% of samples remained at the highest temperature of 750 °C. Synthesized defect perovskite materials were used in the photocatalytic degradation of methylene blue dye under UV light radiation. Furthermore, an excellent photocatalytic degradation is observed for (Rb0.5Cs0.5)2SnCl6 (78% to 85%) compared to other defect perovskite materials even after 120 min irradiation. The increase in photocatalytic efficiency of (Rb0.5Cs0.5)2SnCl6 is due to strong absorption of light, large separation of electron–holes pairs and the size of the nanoparticles. Also, the radical trapping experiment showed that the super oxide radicals (.O2−) and photo-generated holes (h+) were the predominant active species in the photocatalytic degradation of methylene blue dye process. This study concludes that the defect perovskites are the potential materials for photocatalytic application.