Preliminary study of determination of Dinophysis concentration using hyperspectral imaging

Conventional measurement methods were based on microscope, which was time-consuming and complex operation. In this paper, the aim of this work was to preliminary study the feasibility of the rapid and precision determination of Dinophysis concentration at the wavelength of 495-1030 nm. The transmittance spectra of algae liquid were obtained by hyperspectral transmittance image system. The region of interest (ROI) of each hyperspectral images was segmented and the mean spectra data were extracted from the ROI, then the data was arranged in a matrix and applied to further analysis. Partial least square regression (PLSR) was then used to build model with full spectral wavelengths. Nine wavelengths were chosen as the optimal wavelengths using the successive projections algorithm (SPA) to establish the new simplified model (SPA-PLSR) to correlate the selected spectral feature with Dinophysis concentration. By comparing the performance of different models, the best result was by PLSR based on optimal spectral wavelengths with correlation coefficient (R) of 0.9811. The preliminary study revealed the possibility of hyperspectral transmittance imaging as a rapid method to determine Dinophysis concentration.