# Determination of Flibanserin in Female Sexual Desire Enhancer Products by LC–MS/MS and Its Confirmation by LCMS-IT-TOF

## TL;DR

This study developed a method to detect flibanserin in female sexual desire enhancer products in Türkiye and found that most products lacked the drug, raising concerns about authenticity and health risks.

## Contribution

A novel and validated LC–MS/MS method for flibanserin detection in commercial products is introduced.

## Key findings

- The developed method has a low limit of quantification (1.00 ng/mL) and short analysis time (5 min).
- Commercial samples showed absence or very low levels of flibanserin, indicating potential product mislabeling.
- The method was evaluated as sustainable using greenness, blueness, and whiteness metrics.

## Abstract

Hypoactive sexual
desire disorder, a common condition among females,
often goes undiagnosed due to the lack of available pharmaceutical
treatments or the stigma associated with this condition. Flibanserin
was initially investigated as an antidepressant but failed to demonstrate
efficacy for depression; however, subsequent clinical studies revealed
its potential to enhance sexual desire in some individuals, leading
to its approval by the U.S. Food and Drug Administration in 2015 for
the treatment of hypoactive sexual desire disorder. In this study,
a novel LC–MS/MS method was developed and validated for the
determination of flibanserin in commercial products marketed in Türkiye
as female sexual desire enhancers. Chromatographic separation was
achieved using a SunShell C18 column (100 mm × 4.6 mm, 2.6 μm),
with a mobile phase consisting of 0.1% formic acid in methanol and
0.1% formic acid in water (65:35, v/v). The method exhibited a low limit of quantification (1.00 ng/mL)
and a short analysis time of 5 min. The method was fully validated
in accordance with the ICH Q2­(R2) guideline. Accuracy studies performed
on samples in which flibanserin was not detected yielded recovery
values between 90.04% and 94.60%. Interday linearity studies conducted
over 3 days showed no statistically significant differences (p = 0.9823, ANOVA). Commercial samples collected from various
sources were analyzed using both LC–MS/MS and LC-MS-IT-TOF
techniques, revealing the absence or very low levels of flibanserin
in the investigated products, raising concerns regarding product authenticity
and potential risks to women’s health. In addition, the proposed
analytical approach was evaluated using greenness, blueness, and whiteness
metrics, demonstrating its suitability as a sustainable and applicable
method for routine control analyses.