Quantitative, label-free biochemical analysis of single, living cells is a highly sought after modality in the biological sciences. While flow cytometry provides a variety of parameters for characterizing and sorting cells, it currently lacks a method for noninvasive and nondestructive chemical analysis. This chapter introduces Raman spectroscopy as a new component in flow cytometry for label-free analysis and sorting of living cells. While similar in principle to current fluorescence-based sorting systems in its design layout and operation, key differences between the Raman and fluorescence process necessitate research focused on developing novel optical and microfluidic schemes applicable for Raman analysis of cells. A particular emphasis must be placed on addressing the weak Raman signal intensity, which is a major obstacle to realizing a Raman sorting system. Although unlikely to rival current cytometers in its throughput, a Raman system could offer new capabilities such as sorting smaller populations for broad biological applications, especiallywhen noninvasive, label-free analysis of living cells is a key requirement. This chapter will introduce the basic principles of Raman spectroscopy, the basic instrumentation, and both seminal and recent studies that have established the foundation for achieving Raman-activated flow cytometry.
ASJC Scopus subject areas
- Chemical Engineering(all)