On the photoacoustic, photothermal and colorimetric quantification of carotenoids and other phytonutrients in some foods: a review
Bicanic, D.D. - \ 2011
Journal of Molecular Structure 993 (2011)1-3. - ISSN 0022-2860 - p. 9 - 14.
performance liquid-chromatography - thermal lens detection - trans-beta-carotene - optothermal window - lycopene content - tomato products - vegetable-oils - ultrasensitive determination - spectrometric detection - hplc-tls
The performance of various analytical methods is compared in terms of their potentiality to quantify the concentration of carotenoids in some foods accurately and rapidly. High performance liquid chromatography (HPLC) and spectrophotometry (SP), two absolute reference techniques, were used in parallel experiments. The emphasis is on the application of the new methods to significantly reduce the long analysis time (due to a laborious and costly extraction) characteristic for both HPLC and spectrophotometry. Among such direct quantification methods are colorimetry and a variety of novel photoacoustic (PA) and photothermal (PT) detection schemes that obviate the extraction step. The outcome of numerous studies shows a number of important advantages provided by these methods. Furthermore, the promising results suggest that the availability of practical, versatile, compact and affordable quality control instruments that offer a low-cost solution to routine analysis of specific carotenoids in some foods is within reach.
Photoacoustic measurement of lutein in biological matrix
Bicanic, D.D. ; Luterotti, S. ; Becucci, M. ; Fogliano, V. ; Versloot, P. - \ 2005
Journal de Physique IV France 125 (2005). - ISSN 1155-4339 - p. 825 - 828.
performance liquid-chromatography - thermal lens detection - trans-beta-carotene - ultrasensitive determination - vegetable-oils - hplc-tls
Photoacoustic (PA) spectroscopy was applied for the first time to quantify lutein in a complex biological matrix. Standard addition of lutein to a biological low-lutein matrix was used for the calibration. The PA signal was found linearly proportional (R > 0.98) to lutein concentration up to 0.3% (w/w). The dynamic range of concentrations extends to 1% (w/w) lutein. For a given experimental set-up the responsivity of PA detector within the range of linearity was estimated to 1.1 mV/1% lutein. Precision of repeated analyses is good with average RSD values of 4 and 5% for blanks and spiked samples, respectively. The analytical parameters indicate that the PA method is fast and sensitive enough for quantification of lutein in supplementary drugs and in the lutein-rich foods.
Ultratraces of carotenes in tomato purees : HPLC-TLS study
Luterotti, S. ; Markovic, K. ; Franko, M. ; Bicanic, D.D. ; Vahcic, N. ; Doka, O. - \ 2003
Review of Scientific Instruments 74 (2003)1. - ISSN 0034-6748 - p. 684 - 686.
performance liquid-chromatography - thermal lens detection - trans-beta-carotene - ultrasensitive determination - lycopene - isomers - oxygen
The present study was designed to provide information about (i) the profile of carotene pigments and (ii) trace quantities of lycopene and -carotene left in tomato purées. The ultrasensitive method comprising HPLC and thermal lens spectrometric (TLS) detection enabled us to detect as low as 0.3 and 1.1 ng ml¿1 lycopene and -carotene in purée extracts, respectively. Total concentration of -carotene and lycopene (varying from 3 to 170 ng g¿1) in the examined tomato purées may serve as an indicator of the carotene-specific antioxidative capacity of these products. Although conventional spectrophotometry can be used to rapidly assess the quality of products derived from tomatoes, a highly sensitive and selective method such as HPLC-TLS is needed for reliable analyses of samples such as, for example, those subjected to inappropriate storage and/or handling