비정형 고체 시료 분석을 위한 근적외선 투과 측정 방식 연구 및 신속한 분광분석을 위한 다량 시료 로딩 기판 개발

Abstract

Two different NIR spectroscopic schemes enabling of acquiring reproducible spectra of shape-inconsistent solid samples and reliable drop-n-dry measurement using effective sample-loading substrate were developed in this thesis In Chapter 1, a bead-incorporated transmission scheme (BITS) was developed for collecting reproducible transmission near-infrared (NIR) spectra of samples with inconsistent shapes. Isotropically diffused NIR radiation was illuminated around a sample and the surrounding radiation was allowed to interact homogeneously with the sample for transmission measurement. To evaluate the analytical potential of the BITS scheme, two different solid samples of polyethylene (PE) and tourmaline were selected and the densities of individual PE pellets were determined and mining locality for tourmalines was identified. In Chapter 2, several spectroscopic substrates with hydrophobic surface able to form reproducible droplet have been investigated for high throughput drop-n-dry measurement. For this purpose, polytetrafluoroethylene (PTFE) disk, perfluorooctyltrichlorosilane (FTS)- and amine-coated were evaluated as a drop-n-dry substrate for determination of fat concentration in milks. Since the distribution of dried components was not homogeneous in a spot due to so called coffering effect, transmission near-infrared (NIR) spectra were collected by fully covering each spot with a proper optical arrangement to ensure representative sampling. In addition, the same scheme was also used for IR spectroscopic discrimination between wild and transgenic tobaccos using their extracts.