The coronavirus disease 2019 (COVID-19) has become a substantial threat to the international health sector and the global economy. As of 26 December 2021, the number of mortalities resulting from COVID-19 exceeded 5.3 million worldwide. The absence of an effective non-vaccine treatment has prompted the quest for prophylactic agents that can be used to combat COVID-19. This study presents the feasibility of chicken egg yolk antibody (IgY) anti-receptor-binding domain (RBD) spike SARS-CoV-2 as a strong candidate to neutralize the virus for application in passive immunization. For the purpose of preclinical studies, we radiolabeled IgY anti-RBD spike SARS-CoV-2 with radionuclide iodine-131. This allowed us to evaluate several biological characteristics of IgY in vitro, in vivo, and ex vivo. The preclinical data suggest that IgY anti-RBD spike SARS-CoV-2 could specifically bind to the SARS-CoV-2 antigens; however, little uptake was observed in normal cells (MRC-5) (<2%). Furthermore, the ex vivo biodistribution study revealed that IgY predominantly accumulated in the trachea of normal mice compared to other organs. We also found that IgY possessed a good safety profile when used as an intranasal agent. Taken together, we propose that IgY anti-RBD spike SARS-CoV-2 has the potential for application in passive immunization against COVID-19.

HAp and Zr-doped HAp nanoparticles were synthesized from bovine bone and local zircon material by using the hydrothermal method. XRD analysis showed that the HAp and Zr-doped HAp nanoparticles had hexagonal structure with a crystallite size of 20-36 nm and the lattice constants a = 9.8-9.9? and c = 6.5-6.8 ?. XRD data also showed that up to 20 at.% of Zr can be accommodated in HAp crystal structure. The lattice constant and cell volume decreased with increasing Zr concentration. FTIR data confirmed that the majority of functional groups that exist on the surface of the HAp and Zr-doped HAp nanoparticles were the hydroxyl and phosphate groups. Suspensions with the HAp and Zr-doped HAp nanoparticles prepared using citric acid as dispersant were stable with zeta potential between ?31 and ?35mV at pH = 7. Reactive oxygen species are generated on the produced HAp and Zr-doped Hap nanoparticles and confirm their potential for application in photodynamic therapy.

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Supercapacitors have been fabricated from reduced graphene oxide (rGO) based on coconut shell. The production of rGO was started from carbonizing coconut shell at 100 – 140°C of temperature, then sieving of 200 mesh and calcinating at 400°C for 5 hours. The peaks of XRD pattern had indicated rGO phase. Supercapacitor electrodes were fabricated from two different sources of nitrogen for doping. Firstly, the electrode was fabricated from the mixing of the rGO coconut shell, HCl, glucose, FeCl3 bubbled with nitrogen gas (N2). Secondly, it was fabricated from the same starting materials; however, the nitrogen was from the ammonium hydroxide (NH4OH). Cyclic voltammetric characterization indicates that nitrogen atom originating from NH4OH has been more effective to be inserted in rGO for increasing the capacitance of the fabricated supercapacitors.

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