Screening and Identification of Mitragynine and 7-Hydroxymitragynine in Human Urine by LC-MS/MS

Abstract

Kratom is a tree planted in Southeast Asia, including Thailand, Malaysia, Myanmar (Burma) and elsewhere in the region. A long history of usage and abuse of kratom has led to the classification of kratom as a controlled substance in its native Thailand and other Southeast Asian countries. However, kratom is not controlled in the United States, and the wide availability of kratom on the Internet and in the streets has led to its emergence as an herbal drug of misuse. With the increasing popularity of kratom, efficient protocols are needed to detect kratom use. In this study, a rapid method for the analysis of kratom compounds, mitragynine and 7-hydroxymitragynine, in human urine has been developed and validated using high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). The chromatographic system employed a 2.6-µm 100 mm × 2.1 mm phenyl-hexyl analytical column and gradient elution with a 0.4-mL/min flow rate of water and acetonitrile as mobile phases. A triple quadrupole mass spectrometer was used as the detector for data acquisition. The analyst was the quantification software. The established method demonstrated linearity of >0.99 for both analytes, and low detection limits were obtained down to 0.002581 ng/mL for mitragynine and 0.06910 ng/mL for 7-hydroxymitragynine. The validated method has been utilized for clinical analysis of urine for the purpose of mitragynine and 7-hydroxymitragynine detection.

A Mass Spectrometric Study of Kratom Compounds by Direct Infusion Electrospray Ionization Triple Quadrupole Mass Spectrometry

“…A rapid and effective method for quantification of mitragynine and 7-hydroxymitragynine compounds in human urine matrix was reported. Correlation coefficients greater than 0.99 were obtained for both mitragynine and 7hydroxymitragynine compounds in the previous study [21]. In the current study, mass spectrometry part was emphasized with mass spectrum and mass fragments information.…”

“…In the previous study, it was focused on the method development and validation using LC-MS/MS [21]. A rapid and effective method for quantification of mitragynine and 7-hydroxymitragynine compounds in human urine matrix was reported.…”

Kratom: A systematic review of toxicological issues

“…Mitragynine was stable in plasma at room temperature for 6 hr (Parthasarathy et al, 2010) and in refrigerated urine (pH not specified) for 14 days (Fu et al, 2015). Papsun reported that mitragynine was stable in blood containing sodium fluoride and potassium oxalate for 7 days at room temperature and up to 30 days when refrigerated or frozen.…”

Clinical Pharmacology of the Dietary Supplement Kratom (Mitragyna speciosa)

“…Recently, several methods have been developed to rapidly identify kratom alkaloids in human urine [161][162][163][164][165] ; this approach can be especially helpful in deciding the treatment course of an unresponsive patient presenting with suspected kratom toxicity. Fu et al 166 developed a sensitive and specific LC-MS/MS method for the efficient detection of MG and 7-OH-MG in urine. Several previously conducted studies also described the analysis of MG and 7-OH-MG in human urine, using various chromatographic methods.…”