ABSTRACT
Polarized three-dimensional fluorescence spectra of different kinds of milk were measured, including pure milk, milk with high calcium, and milk with high calcium but low fat produced by YiLi and MengNiu. It was found that the fluorescence intensity is stronger when excitation and emission polarizer orientation is parallel. The angle between excitation dipole and emission dipole of all kinds of milk equivalent chromophore was estimated by a simple model, indicating that they all less than 40 degrees. The angle for milk with high calcium but low fat is less than that of pure milk and milk with high calcium. And in the experiment, the polarized fluorescence intensity of milk with high calcium but low fat is significantly greater than the others, which fitted with the model estimation.
Subject(s)
Imaging, Three-Dimensional/methods , Milk/chemistry , Spectrometry, Fluorescence/methods , Animals , Cattle , Fluorescent Dyes/chemistry , Quality ControlABSTRACT
The cholesterol with different concentration in hypercholesterolemia serum was studied by the method of spectroscopy technology. The absorption and fluorescence spectra of normal human serum and hypercholesterolemia serum were obtained respectively; the spectral characteristic of each sample and the difference between two kinds of samples were discussed too. The results indicate that the absorption and fluorescence spectra of hypercholesterolemia serum are different from those of normal human serum. The absorptivity and the fluorescence intensity of hypercholesterolemia serum are both higher than those of normal human serum. Besides, there are new absorptive peaks and new fluorescence peaks in the spectrogram. Thus, the abnormalism of cholesterol in serum can be judged by comparing the absorption and fluorescence spectra. The researches in the present paper provide an experimental foundation for the diagnosis of cholesterol in blood.
Subject(s)
Cholesterol/chemistry , Hypercholesterolemia/diagnosis , Spectrophotometry/methods , Blood Chemical Analysis , Cholesterol/blood , Humans , Hypercholesterolemia/bloodABSTRACT
Ethanol solution can emit visible fluorescence when induced by UV light. With emission spectral profiles similar on the whole, the peaks are red-shifted distinctly when the excitation light alters from 200 to 250 nm. And the spectral profiles of ethanol solutions with different concentrations are also red-shifted when induced by the same wavelength of excitation light. A thorough analysis of the rule of spectrum peaks that are red-shifted is carried out and discussed in theory and in experiment. Investigation on the intrinsic fluorescence spectrum of ethanol solution and its characteristics will contribute to the study of the fluorescence spectra when ethanol serves as a solute and hydrolysis catalyst. Especially, this study will also help to offer a sensitive method of the determination of ethanol.
