Analysis of Mitragynine and Speciociliatine in Umbilical Cord by LC-MS/MS for Detecting Prenatal Exposure to Kratom.

Kratom is an herbal drug which is legal in the United States. While it is marketed as a safer alternative to opioids, it can cause opioid-like withdrawal symptoms when discontinued after regular use. Several case studies have shown that kratom exposure in-utero can lead to symptoms in newborns consistent with neonatal abstinence syndrome. Here we present a validated method for the detection of kratom in umbilical cord by liquid chromatography tandem mass spectrometry (LC-MS/MS). Umbilical cord is homogenized in solvent and kratom analytes are purified by solid phase extraction (strong cation exchange). Diastereomeric kratom alkaloids mitragynine (MG), speciociliatine (SC), speciogynine (SG), and mitraciliatine (MC) are separated by reverse phase chromatography on a phenyl hexyl column. Applying this method to residual umbilical cords submitted to our laboratory for drug testing, twenty-nine positive specimens exhibiting varied kratom analyte distributions were observed. MG and SC were the most abundant kratom analytes and were selected as biomarkers of kratom exposure. A cutoff concentration of 0.08 ng/g was established for both MG and SC.