A background subtraction approach for determination of endogenous cortisol and 6 beta-hydroxycortisol in urine by UPLC-MS/MS with application in a within-day variability study in HIV-infected pregnant women

Author(s)

de Lima Benzi, Jhohann Richard ^[1] ; Moreira, Fernanda de Lima ^[1] ; Marques, Maria Paula ^[1] ; Duarte, Geraldo ^[2] ; Suarez-Kurtz, Guilherme ^[3] ; Lanchote, Vera Lucia ^[1]

Affiliation

^[1] Univ Sao Paulo, Sch Pharmaceut Sci Ribeirao Preto, Dept Clin Toxicol & Bromatol Anal, Ave Cafe S-N, Campus USP, BR-14040903 Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Ribeirao Preto Med Sch, Ribeirao Preto, SP - Brazil

^[3] Natl Canc Inst, Rio De Janeiro, RJ - Brazil

• Document type: Journal article
• Source: JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES; v. 1144, MAY 1 2020.
• Web of Science Citations: 0

Abstract

Different methods have been used for CYP3A phenotyping, such as probe drugs or the urinary index 6 beta-hydroxycortisol/cortisol ratio (6 beta-OHF:C). This work describes a simple and affordable method for the simultaneous determination of the endogenous compounds cortisol and 6 beta-hydroxycortisol in urine using a background subtraction approach. The method was applied to investigate the CYP3A activity in HIV-infected pregnant women (n = 9) in the third trimester and postpartum periods. Also, the within-day variability in the 6 ss-OHF:C index was also evaluated. The sample preparation consists of a pre-cleanup with acetonitrile followed by liquidliquid extraction with ethyl acetate. The analytes were resolved by employing an Acquity UPLC (R) BEH C18 column with a mobile phase that consisted of a mixture of acetonitrile containing 0.1% formic acid and 0.1% formic acid in gradient mode. The method presented linearities of 1-1.000 ng/mL and 2-1.000 ng/mL for C and 6 beta-OHF, respectively, and presented acceptable precision and accuracy. Qualitative and quantitative matrix effects tests were also performed. A high 6 beta-OHF:C within-day variability was observed in both phases. In the third trimester period, the 6 beta-OHF:C ranged from 2.57 to 51.69, with a mean +/- standard deviation (SD) of 15.12 +/- 5.41 (n = 9). Similar values were obtained in the postpartum period, with 6 beta-OHF:C ranging from 3.48 to 44.54 with a mean +/- SD of 14.37 +/- 5.73 (n = 7). Even though the 6 beta-OHF:C is a non-invasive index for CYP3A phenotyping, its use is susceptible to high within-day variability. (AU)

• FAPESP's process: 19/03429-4 - Pyelonephritis impacts on Organic Anion Transporters (OAT) 1 and 3 activity in pregnant women: a quantitative system pharmacology approach
• Grantee: Jhohann Richard de Lima Benzi
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 18/05616-3 - Clinical pharmacokinetics in infectious diseases
• Grantee: Vera Lúcia Lanchote
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 16/23938-2 - Influence of pregnancy associated with HIV on the activity of OATP drug transporter in patients under treatment with Efavirenz
• Grantee: Fernanda de Lima Moreira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral