A NEW METHOD FOR THE RAPID MEASUREMENT OF CHOLESTEROL CRYSTALLIZATIONIN MODEL BILES USING A SPECTROPHOTOMETRIC MICROPLATE READER

Measurements of the cholesterol crystal observation time, and particul arly the crystal growth rate in model biles, are important in biliary pathophysiology. The aim of this study was to develop a semi-automated method permitting multiple, simultaneous, and precise measurements of the crystal growth rate in model biles. Incubated model biles were mi xed with a high concentration of NaTDC to solubilize noncrystalline tu rbidity and spectrophotometric measurements were performed. In paralle l, samples were observed by light microscopy. The absorbance correlate d linearly with the crystal mass and permitted quantitation of the cry stal growth rate. Polarized light microscopy was more sensitive than s pectrophotometry for determining the initial crystal observation time, while spectrophotometry was more precise and quantitative for measuri ng the crystal growth rate.