Analytical Sciences

Abstract − Analytical Sciences, 34(9), 1017 (2018).

Proton Affinitive Derivatization for Highly Sensitive Determination of Testosterone and Dihydrotestosterone in Saliva Samples by LC-ESI-MS/MS
Ken-ichi OHNO,* Tomomi HASEGAWA,* Tomomi TAMURA,* Haruka UTSUMI,* and Kouwa YAMASHITA**
*Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, 4-1 Komatsushima 4-chome, Aoba, Sendai, Miyagi 981-8558, Japan
**Yokohama University of Pharmacy, 601 Matano-cho, Totsuka, Yokohama, Kanagawa 245-0066, Japan
In this study, proton affinitive derivatization using picolinic acid and its analogs (3- and 6-methylpicolinic acid and 5-butylpicolinic acid) with proton affinitive moieties was performed for the highly sensitive determination of testosterone (T) and 5α-dihydrotestosterone (DHT) in saliva by LC-ESI-MS/MS. T and DHT were converted to their corresponding picolinate esters and their chromatographic behavior was investigated with a reversed phase column. The picolinate ester of each steroid exhibited a clear single peak and elution occurred in the following order: picolinate, 3/6-methylpicolinate, and 5-butylpicolinate. Estimation and understanding of the separation and retention time of each picolinate ester was made simple using the develop method. Although the peaks of picolinate and 3/6-methylpicolinate esters were suppressed by interference from the saliva background (matrix effect), the 5-butylpicolinate esters were only marginally affected.