News & Events

Faith Howell

Posted on April 25, 2018


Date - April 25, 2018
1:00 pm - 2:00 pm


MS Thesis Defense – CHE 602
Talk Title: Mass Spectrometric Detection of Cortisol in Hair Samples
Advisor: Dr. Norman Chiu



Stress is typically measured through time consuming and questionable psychological and physical factors. Our research focuses on determining the level of cortisol accumulated in human hair, and related the cortisol level to the stress of a particular individual had experienced. We are replacing a commercialized immunodetection method for measuring extracted cortisol with a liquid chromatography mass spectrometry (LC-MS) method due to its benefits of higher sensitivity and lower running costs. In the LC-MS method, reversed phase chromatography is used. The eluent from the LC column is evaporated and ionized by electrospray ionization technique. The mass spectrometric measurements are carried out by using selected ion reaction monitoring (SRM) mode in a triple quadrupole instrument. In the calibration experiments, the limit of detection of 0.24ng/mL of cortisol and a linear dynamic range of 0.80-500ng/mL were achieved.