Use of SRS microscopy for imaging drugs

The study of drugs at a cellular level has the capacity to provide meaningful information on drug distribution, mechanism, pharmacokinetics, and metabolism. A comprehensive understanding of drug behavior in cells represents an essential facet of drug discovery, with great time and expense spent to ensure the safety and efficacy of pharmaceutical compounds. Stimulated Raman scattering (SRS) imaging offers unique advantages over other molecular and microscopic imaging techniques, namely excellent spatiotemporal resolution and chemical specificity. SRS allows a drug to be imaged either by inherent features of its molecular structure or by attachment of a small, spectroscopically bioorthogonal Raman-active tag which resonates within the cell-silent region, precluding the requirement for bulky labels. Advances in SRS technologies have facilitated the imaging of drugs in three major categories: cancer therapeutics, dermatological drugs, and drug delivery systems. Within each of these categories, a fuller understanding of drug mechanisms, quantitative determination of drug concentration, and intracellular localization of drug compounds has allowed invaluable insight to be obtained.