Publications by authors named "Yeonjoo Ahn"

In this study, we examined the potentially beneficial effects of bovine colostrum-derived exosomes on UV-induced aging and damage in three major resident skin cells including keratinocytes, melanocytes, and fibroblasts. The treatment with colostrum exosomes prevented the UV-induced generation of intracellular reactive oxygen species in epidermal keratinocytes. In UV-stimulated melanocytes, colostrum exosomes could also significantly reduce the production of the protective skin-darkening pigment melanin, which may help to reduce the risk of excessive melanin formation causing skin hyperpigmentation disorders.

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New enzymatic catalysts prepared using physical entrapment and chemical bonding were used as anodic catalysts to enhance the performance of enzymatic biofuel cells (EBCs). For estimating the physical entrapment effect, the best glucose oxidase (GOx) concentration immobilized on polyethyleneimine (PEI) and carbon nanotube (CNT) (GOx/PEI/CNT) was determined, while for inspecting the chemical bonding effect, terephthalaldehyde (TPA) and glutaraldehyde (GA) crosslinkers were employed. According to the enzyme activity and XPS measurements, when the GOx concentration is 4 mg mL(-1), they are most effectively immobilized (via the physical entrapment effect) and TPA-crosslinked GOx/PEI/CNT(TPA/[GOx/PEI/CNT]) forms π conjugated bonds via chemical bonding, inducing the promotion of electron transfer by delocalization of electrons.

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