Sample preparation for Raman microspectroscopy
in: Physical Sciences Reviews (2020)
Raman spectroscopy and its variants allow for the investigation of a wide range of biological and biomedicalsamples, i.e. tissue sections, single cells and small molecules. The obtained information is on a molecular level.By making use of databases and chemometrical approaches, the chemical composition of complex samples canalso be defined. The measurement procedure is straight forward, however most often sample preparation proto-cols must be implemented. While pure samples, such as high purity powders or highly concentrated chemicalsin aqueous solutions, can be directly measured without any prior sample purification step, samples of bio-logical origin, such as tissue sections, pathogens in suspension or biofluids, food and beverages often requirepre-processing steps prior to Raman measurements. In this book chapter, different strategies for handling andprocessing various sample matrices for a subsequent Raman microspectroscopic analysis were introduced illus-trating the high potential of this promising technique for life science and medical applications. The presentedmethods range from standalone techniques, such as filtration, centrifugation or immunocapture to innovativeplatform approaches which will be exemplary addressed. Therefore, the reader will be introduced to methodsthat will simplify the complexity of the matrix in which the targeted molecular species are present allowingdirect Raman measurements with bench top or portable setups.