Laser Detection Technology Monitors Heart Health Through the Breath

Our breath is a mixture of many gases. Nitric oxide has an important function of being a signaling molecule in the cardiovascular system, and it takes many different pathways through our body. Gerard Wysocki, assistant professor of electrical engineering at Princeton University, discusses his laser technology for detecting nitric oxide in the breath as a way for doctors to monitor patient health. Wysocki uses a laser to perform optical spectroscopy. He uses three major elements: the laser, a gas cell between two polarizers, and a photo detector. Wysocki came up with a new method of suppressing noise by modulating the laser at really high frequencies. Subsequent modulation at that high frequency allows him to reach fundamental quantum noise levels, allowing the measurement to be performed at really high sensitivities. Wysocki is the first to be able to measure nitric oxide isotopes in breath, urine, and blood samples simultaneously.