Explore the groundbreaking world of ultra-sensitive biosensors in this 40-minute lecture by Professor Stephen Arnold from New York University (NYU) Tandon. Delve into the motivation behind and history of Whispering Gallery Mode bio-sensors, understanding their crucial role in pathogen detection, particularly viruses. Gain insights into molecular spectroscopy, label-free detection methods, and the physics behind frequency spectrum and line width. Discover the applications of distributed feedback lasers and microfluidics in creating highly sensitive detection systems. Learn about cutting-edge techniques for single virus detection, with a focus on influenza, and understand how these innovations are revolutionizing the field of biosensing and disease prevention.