Papers by Author: Seung Jin Lee

Abstract: To use nanobiosensors as diagnostic devices, they should be evaluated and approved as medical devices before marketing. This study was performed to establish appropriate evaluation guidelines that provide how to verify the safety and effectiveness of a novel nanobiosensor as a medical device. We prepared an enzymeless glucose sensor with nanoporous platinum electrode to evaluate performance and stability by comparing it with a commercial enzyme-based glucose sensor. Through these evaluation studies, we developed guidelines, and the guidelines consist of five parts: evaluation of analytical performance, clinical performance, safety, stability, and design and quality control systems. Analytical and clinical performance of nanobiosensors should be evaluated by accuracy, sensitivity, reproducibility, cut-off value, and other specific performance characteristics. Also, electric, mechanical, and biological safety should be evaluated. With the performance and safety, validation of storing conditions and shelf life should be established with evaluation and characterization of nano-structured parts for stability evaluation. Then, design and quality control systems should be evaluated in the aspect of quality requirements, material, manufacturing process, and final product. These guidelines will be helpful for facilitating the commercialization of the safe, effective, and novel diagnostic nanobiosensors into market place.

Abstract: Poly (D,L-latic-co-glycolic acid) (PLGA) has been used as the artificial scaffold for blood vessel formation. In order to hinder smooth muscle cell (SMC) angiogenesis, new scaffold design method of loading Epigallocatechin 3-O-gallate (EGCG) on PLGA film was introduced. PLGA and EGCG were dissolved in acetone and film-shape scaffold was manufactured. Antiangiogenetic effect of EGCG released on scaffold was analyzed for SMC and human umbilical vein endothelial cell (HUVEC) and method for selective inhibition from the difference of growth of SMC and HUVEC was suggested.

Abstract: Novel poly(ε-caprolactone)-organosiloxane hybrid containing amine group was synthesized through sol-gel method. Triethoxysilane end-capped poly(ε-caprolactone) was prepared by reaction with α,ω-hydroxyl poly(ε-caprolactone) and 3-isocyanatopropyl triethoxysilane. It was then hydrolyzed and co-condensed with aminopropyl triethoxysilane through sol-gel method. The success of hybridization was evaluated by FT-IR by new formation of siloxane group. Osteoblast-like cell responses were assessed on this new hybrid material for the potential application as a bone tissue engineering scaffold. The cell responses were compatible with those on pure poly(ε-caprolactone) used as a control.