Optical Biosensors for Medical Diagnostics

Detection of biologically relevant targets such as microorganisms, DNA, proteins, or small molecules at low concentrations is important for applications in medical diagnostics, pharmaceutical development, food safety, defense, and environmental monitoring. Of particular interest are point-of-care biosensing systems that can be employed outside of a laboratory environment and without the need of highly trained staff. Our work is focused on the design of label-free biosensing schemes which employ micro- and nano-structured silicon surfaces, as the optical transducer element, interfaced with relevant of capture probes (e.g., antibodies and aptamers). In this lecture, I will highlight design principles employed to engineer these biosensors, and I will discuss the evaluation and application of these platforms for rapid antimicrobial susceptibility testing (AST) directly from clinical samples, and sensitive detection of protein biomarkers in complex fluids.