Novel strategy for fluorescence determination of glibenclamide in samples with high concentration of caffeine based on a low-pressure flow injection chromatography system

• Published in: Microchemical journal 2018-11, Vol.142, p.288-296
• Main Authors: González, Natalia, Lantmann Corral, Sara P., Lista, Adriana G., Acebal, Carolina C.
• Format: Article
• Language: English
• Subjects: Caffeine; Drug facilitated crime; Energy drink; Fluorescence; Glibenclamide; Low-pressure flow injection chromatography system
• ISSN: 0026-265X; 1095-9149
• DOI: 10.1016/j.microc.2018.07.005

In this work, a new low-pressure flow injection chromatography (FIA-C) system with fluorescence detection was developed for the toxicological control of glibenclamide in beverages with high caffeine content. As caffeine quenched the fluorescence signal of glibenclamide, a separation of the analyte from the sample matrix was proposed as a simple and rapid strategy. The separation was performed in a commercially available monolithic column (RP-18e, 25 mm × 4.6 mm i.d.) inserted in a flow injection system. The mobile phase used for analysis was acetonitrile/acetic acid (50:50 v/v), with a flow rate of 1.03 mL min−1. For each analysis, only 5.2 mL of mobile phase was used. After the optimization of the variables of the system, a calibration curve with a linear range between 0.50 and 10.0 mg L−1 was obtained (R2 = 0.997). The precision of the proposed method was evaluated in terms of the relative standard deviation obtaining 0.58 and 1.68% for the intra-day precision and inter-day precision, respectively. The detection limit was 0.10 mg L−1 and the sample throughput, taking into account the whole procedure, was 12 h−1. The method was applied to fortified real samples with satisfactory recovery values (90.4–103.7%). On the other hand, samples adulterated with commercially GLB pills were also analyzed with very good results (96.5–104.5%). Simple and fast FIA-C system with fluorescence detection to determine glibenclamide in samples with high caffeine content. [Display omitted] •A simple method was developed for the toxicological control of glibenclamide (GLB).•The effect of caffeine in the fluorescence intensity of GLB is established.•A flow injection chromatography system is proposed as strategy for GLB determination.•The determination of GLB in real samples was performed without pretreatment.•Energy drink samples were analyzed with satisfactory results.