X-Ray Fluorescence Analysis in Biology and Medicine

Abstract

X-ray fluorescence analysis (XRF) is widely used when determining the concentrations of elements in various materials in biological research. Current review considers the achievements related to the features of the XRF method. X-ray fluorescence analysis in most cases is a non-destructive method that has proven its potential for measuring the concentrations of elements with a high atomic number Z in organs and tissues in vivo. The main areas of its application in biology and medicine are content determination of basic and toxic elements in plants, samples of bones, teeth, hairs, nails and tissues of vital organs, body fluids such as blood, serum, plasma, saliva, urine, etc. Usually, these studies are part of applied programs that include environmental and metabolic analyses of the population, including the influence of professional factors. The advantages of XRF are also discussed with regards to biological materials. It is noted that the form of the element in the sample practically does not affect the analysis result. In recent years, several new XRF spectrometers models have been designed, where polycapillary lenses and half lenses are used as collimating systems. This is important in the case of in vivo application of X-ray fluorescence determination of certain elements in bones and tissues. The dynamic development is typical for detectors with thermoelectric cooling. Variants of preparation of biological materials for analysis are discussed (grinding, dry or wet ashing, acid decomposition, use of suspensions in the case of XRF with TIR). The results of evaluating the interelement effects for XRF of materials of plant origin, including herbs, spices, apple leaves, birch and tomato leaves, tea, wheat, rye, rice, oatmeal, flax flour, beans, ground, and instant coffee are presented. Examples of the use of XRF in various types of forensic research are considered: poisoning, counterfeiting of drugs and food brands, dental implants, identification of remains. The review presents examples of the participation of Russian X-ray physicists in solving the problems under consideration. The list of references is 400 papers, mainly including the publications of the last 20 years.