Determination of glycolic acid in cosmetics by online liquid chromatography-Fourier transform infrared spectrometry.

Department of Analytical Chemistry, Universitat de València, Edificio Jeroni Muñoz, 50th Dr. Moliner, 46100, Burjassot, Spain.
Analytical and Bioanalytical Chemistry (Impact Factor: 3.66). 11/2008; 392(7-8):1383-9. DOI: 10.1007/s00216-008-2430-0
Source: PubMed

ABSTRACT An isocratic online liquid chromatography Fourier transform infrared procedure has been developed for the determination of glycolic acid in cosmetics. The method involves the ultrasound-assisted extraction of glycolic acid from the samples with an acetonitrile:phosphate buffer (25 mM, pH 2.7) (3:97 v/v). The extracts were centrifuged and filtered before their injection into the chromatography system, which was equipped with a C18 column and used a flow rate of 150 microL min(-1). FTIR spectra were acquired using a time-resolved rapid scan mode. To calculate the chromatograms, the spectral area was integrated between 1288 and 1215 cm(-1), with baseline correction established between 1319 and 1150 cm(-1), after correcting for the eluent spectral background. Peak area values of the extracted sample chromatograms were interpolated from an external calibration curve. The method provided a limit of detection of 0.034 mg mL(-1) and a relative standard deviation of 6% for five measurements at the 0.174 mg mL(-1) concentration level. Recovery values obtained by spiking 400 mg of three commercially available samples with amounts of glycolic acid from 3.7 to 9.8 mg ranged between 99.6 and 101%. The results obtained for the commercial samples agree well with their declared concentrations. An attempt to directly determine glycolic acid by attenuated total reflectance measurements using partial least squares calibration showed that results were strongly influenced by compounds coextracted from the matrix.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Recently, various approaches have been addressed to improve chromatographic performance in terms of sensitivity or selectivity, from the development of novel on-line (or off-line) enrichment methodologies, to the improvement of stationary-phase type and multi-dimensional chromatography, to novel and more performing detectors such as tandem mass spectrometry (MS/MS), Nuclear Magnetic Resonance (NMR), and Infrared Spectrometry (IR). For the analysis of complex matrices (e.g., biological fluids, plant extracts, food, and environmental samples), coupling chromatographic instrumentation with these detectors provides a powerful analytical device that can be applied in many fields, such as analysis of pharmaceutical and natural products (and medicinal plant), quality control, environmental trace analysis.This review describes major advances in the HPLC field in terms of enrichment techniques, chromatographic separation and especially in terms of detector improvement for a complete identification and quantification of targeted analytes. The possibility of high-throughputs analyses, as a consequence of sensitivity and selectivity enhancement in drug and metabolites profile and multi-residue assays for natural compounds and/or products containing natural species, is also highlighted. Finally, it is shown how multivariate analysis may enhance analytical performance in terms of useful analytical information that can be extracted from experimental data and in terms of methods for exploring and modelling data. Chemometrics provides tools for making the most of analytical signal, once selectivity and sensitivity have been improved from the chemical point of view.
    Instrumentation Science & Technology 03/2012; 40(2-3):112-137. · 0.43 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A new methodology for simultaneous quantitative analysis of allantoin and glycolic acid in snail mucus and cosmetic creams was developed. HPLC separation was achieved a Synergi-Hydro RP column within 7min using isocratic elution with potassium phosphate (pH 2.7; 10mM) at a flow rate of 0.7mL/min at 30°C. Sample pretreatment was performed by dilution of mucus or cosmetic cream in the elution buffer, heating at 60°C for 20min, adjusting the pH to 2.9 and purification with hexane extraction. Linearity was determined with spiked samples and the LLOQ values of 0.0125 and 0.2500mg/mL were determined for allantoin and glycolic acid, respectively. Accuracy and intra- and inter-day repeatability were studied at three levels of concentrations (0.04, 0.08 and 0.16mg/mL for allantoin and 0.1, 1.5 and 4.0mg/mL for glycolic acid) using spiked mucus and cream base samples; mean values of recovery were in the range of 96.81-102.42% in all matrices tested, whereas the respective RSDs (%Relative Standard Deviation) were less than 3.04% in all cases. Spiked mucus and cream samples were stable (RSD<4.16 and relative error<4.34%) at room temperature and at 4°C for 1 week and at -18°C for 6 months; samples were also stable after three freeze-thaw cycles. The method was applied to the analysis of different lots of snail mucus, and of three commercial creams containing snail mucus.
    Journal of Chromatography A 11/2013; · 4.61 Impact Factor
  • Source