High Performance Liquid Chromatographic Methods for Analysis of Taurine in Energy Drinks after Pre-column Derivatization

Abstract

Simple and efficient high performance liquid chromatography (HPLC) with photodiode array (PDA) and fluorescence (FLD) detection methods have been validated for determination of taurine in energy drinks. These methods are based on pre-column derivatization of taurine with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) at alkaline medium to form colored fluorescent product. In the both validated HPLC methods, the derivatization product is separated on Intersil ODS-3 analytical column with acetonitrile and 0.1% trichloroacetic acid (30:70, v:v) as mobile phase. The eluted derivative is detected at 472 nm for HPLC-PDA and 472 nm/530 nm (Ex/Em) for HPLC-FLD. The methods were validated in terms of linearity, limit of detection (LOD), limit of quantification (LOQ), precision and accuracy (recovery). Good linearities were achieved for taurine (r 2 > 0.9998 and 0.9993) in the concentration range of 5-50 mg L-1 and 5-50 µg L-1 for HPLC-PDA and HPLC-FLD respectively. The LODs were 0.296 and 0.616 × 10-3 mg L-1 for HPLC-PDA and HPLC-FLD respectively. The precision for peak area were 0.78 and 0.61% for HPLC-PDA and HPLC-FLD respectively. Recoveries of taurine ranging from 92-103.3%), (n = 3) were obtained. The validated method was successfully applied for the determination of taurine in some selected energy drinks available in local markets.

Utilization of 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) as a fluorogenic reagent for the development of a spectrofluorometric assay method for taurine in energy drinks

“…9 In addition, the current method recorded a lower level of the linear range than that of a previously described spectrophotometric method. 8 Notably, the LOQ values of previous high performance liquid chromatography (HPLC) methods with UV, 13 fluorescence 13 and MS detection were lower than that of the current method. For a previous capillary electrophoresis/UV method, 3 a higher level and a wider linear range was obtained from the previous method compared to that was obtained from the current method.…”

“…In this context, spectrophotometry, 8 spectrofluorometry, 9 Fourier transform infrared (FTIR) spectrometry, 10,11 and Fourier-transform mid-infrared spectrometry 12 have all been exploited for assaying taurine in energy drinks. High- performance liquid chromatography coupled with ultraviolet (UV), 13–16 fluorescence, 13 mass spectrometric 17 and evaporative light scattering 16 detection methods are utilized. In addition, capillary electrophoresis with UV, 3,18 fluorescence 19 and contactless capacitive coupled conductivity detection 18,20,21 methods have been reported.…”

4-Chloro-7-Nitrobenzofurazan (Nbd-Cl) as Pre and Post-Column Derivatization Reagent for Amine Groups Analysis Using Chromatography: A Mini-Review

“…Omer et al [38] developed and validated a simple and efficient HPLC method for the determination of taurine in energy drinks using HPLC with photodiode array (PDA) and fluorescence (FLD) detection. The method is based on the derivatization of taurine with NBD-Cl at alkaline condition.…”

Liquid Chromatographic and Spectrophotometric Determination of Taurine in Energy Drinks Based on O-Phthalaldehyde-Sulfite Derivatization

“…The limit of detection (LOD) and limit of quantification (LOQ) of these methods were calculated from the calibration curve data. They were determined according the following formula: LOD = 3.3× SDa/b, and LOQ = 10× SDa/b, where: SDa is the standard deviation of intercept, b is the slope [17]. LOD and LOQ were found to be 0.141, 0.109 mg L -1 and 0.423, 0.328 mg L -1 for UV-Vis spectrophotometer and HPLC-PDA analysis respectively, table 1.…”

“…Since taurine has no chromophore, a derivatization step is important to permit its detectability using optical detection [1,5]. Many reagents have been used for taurine derivatization such as 2,4-dinitrofluorobenzene (DNFB) [2], 2-[2-(dibenzocarbazol)-ethoxy]ethyl chloro-formate (DBCEC) [14], ninhydrine [15], Hantzsch reagent, tetracyanoethylene [12], 4-(5,6-dimethoxy-2-phthalimidinyl)-2 methoxyphenylsulfonyl chloride (DMS-Cl) [15], phenol and sodium hypochlorite [16], 4-chloro-4-nitrobenz-2oxa-1,3-diazole (NBD-Cl) [17] , fluorescamine [18], and O-phthalaldehyde (OPA) [19][20][21].…”