Sensing of triglyceride concentration in blood solution using photoacoustic microscopy.

The level of triglyceride (TG) in blood is essential to human health, and hypertriglyceridemia (TG level > 150 mg/dL) would lead to cardiovascular disease and acute pancreatitis that threaten human life. Routine methods for measuring the TG level in blood depend on a lipid panel blood test, which is invasive and not convenient. Here, we use photoacoustic (PA) microscopy to test the PA amplitude of blood solutions (based on hemoglobin powder as well as flowing sheep blood) with different TG concentrations. Interestingly, we observe that the PA amplitude increases with increasing TG concentration in blood solutions, which is attributed to the increase of the Grüneisen coefficient. The preliminary in vitro study shows that the PA methodology is able to detect the TG level down to 450 mg/dL. This finding provides an opportunity for using photoacoustics to noninvasively diagnose hypertriglyceridemia.