KCS

To investigate the variation of Raman spectral feature depends on particle size and its influence on accuracy of quantitative analysis, pellets composed of lactose (5-15wt%) and polyethylene (PE) were prepared, and the corresponding Raman spectra were acquired. For the preparation of pellets, the sizes of lactose were varied (below 50, 50-100, 100-200, 200-300, over 300um), while the size of polyethylene (PE) was unchanged. When the size of lactose particle was smallest, the band shape was dissimilar to those with different particle sizes. The origin for the difference is now under investigation in conjunction with the particle size as well as porosity using Monte-Carlo simulation. Finally, the lactose concentrations were determined using partial least squares (PLS) regression and the dependency of accuracy on the particle size was searched.