Prediction of cholesterol content in gallstones by FTIR spectroscopy coupled with chemometric tools

Gallstones are stone-like deposits that most often develop inside the human gallbladder. In this study, the quantification of cholesterol gallstones was monitored using the Fourier transform mid-infrared (FT-MIR) spectroscopy technique and chemometrics tools. To detect the presence of outliers in the spectral data before developing a prediction model, principal component analysis (PCA) was utilized for qualitative analysis. The application of the partial least square (PLS) calibration models for the quantification of cholesterol demonstrated high-performance capabilities, as indicated by high values of correlation coefficients R2 greater than 0.999, and lower values of root mean square error (RMSE) less than 0.493. According to our results, FT-MIR spectroscopy combined with chemometrics approaches can be used successfully as a simple, quick, and non-destructive method for the quantification of cholesterol in biliary lithiasis.