Quantitative Raman Analysis of Carotenoid Protein Complexes in Aqueous Solution
Carotenoids are naturally abundant, fat-soluble pigmented compounds with dietary, antioxidant and vision protection advantages. The dietary carotenoids, Beta Carotene, Lutein, and Zeaxanthin, complexed with in bovine serum albumin (BSA) in aqueous solution, were explored using Raman spectroscopy to...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-07-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/27/15/4724 |
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| author | Joy Udensi Ekaterina Loskutova James Loughman Hugh J. Byrne |
| author_facet | Joy Udensi Ekaterina Loskutova James Loughman Hugh J. Byrne |
| author_sort | Joy Udensi |
| collection | DOAJ |
| description | Carotenoids are naturally abundant, fat-soluble pigmented compounds with dietary, antioxidant and vision protection advantages. The dietary carotenoids, Beta Carotene, Lutein, and Zeaxanthin, complexed with in bovine serum albumin (BSA) in aqueous solution, were explored using Raman spectroscopy to differentiate and quantify their spectral signatures. UV visible absorption spectroscopy was employed to confirm the linearity of responses over the concentration range employed (0.05–1 mg/mL) and, of the 4 Raman source wavelengths (785 nm, 660 nm, 532 nm, 473 nm), 532 nm was chosen to provide the optimal response. After preprocessing to remove water and BSA contributions, and correct for self-absorption, a partial least squares model with R<sup>2</sup> of 0.9995, resulted in an accuracy of the Root Mean Squared Error of Prediction for Beta Carotene of 0.0032 mg/mL and Limit of Detection 0.0106 mg/mL. Principal Components Analysis clearly differentiated solutions of the three carotenoids, based primarily on small shifts of the main peak at ~1520 cm<sup>−1</sup>. Least squares fitting analysis of the spectra of admixtures of the carotenoid:protein complexes showed reasonable correlation between norminal% and fitted%, yielding 100% contribution when fitted with individual carotenoid complexes and variable contributions with multiple ratios of admixtures. The results indicate the technique can potentially be used to quantify the carotenoid content of human serum and to identify their differential contributions for application in clinical analysis. |
| first_indexed | 2024-03-09T12:22:20Z |
| format | Article |
| id | doaj.art-f05ea46bb5054ceaa3762690666f1cab |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-03-09T12:22:20Z |
| publishDate | 2022-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-f05ea46bb5054ceaa3762690666f1cab2023-11-30T22:39:38ZengMDPI AGMolecules1420-30492022-07-012715472410.3390/molecules27154724Quantitative Raman Analysis of Carotenoid Protein Complexes in Aqueous SolutionJoy Udensi0Ekaterina Loskutova1James Loughman2Hugh J. Byrne3FOCAS Research Institute, Technological University Dublin, City Campus, Camden Row, Dublin 8, D08 CKP1 Dublin, IrelandSchool of Physics and Clinical and Optometric Sciences, Technological University Dublin, City Campus, Grangegorman, Dublin 7, D07 EWV4 Dublin, IrelandSchool of Physics and Clinical and Optometric Sciences, Technological University Dublin, City Campus, Grangegorman, Dublin 7, D07 EWV4 Dublin, IrelandFOCAS Research Institute, Technological University Dublin, City Campus, Camden Row, Dublin 8, D08 CKP1 Dublin, IrelandCarotenoids are naturally abundant, fat-soluble pigmented compounds with dietary, antioxidant and vision protection advantages. The dietary carotenoids, Beta Carotene, Lutein, and Zeaxanthin, complexed with in bovine serum albumin (BSA) in aqueous solution, were explored using Raman spectroscopy to differentiate and quantify their spectral signatures. UV visible absorption spectroscopy was employed to confirm the linearity of responses over the concentration range employed (0.05–1 mg/mL) and, of the 4 Raman source wavelengths (785 nm, 660 nm, 532 nm, 473 nm), 532 nm was chosen to provide the optimal response. After preprocessing to remove water and BSA contributions, and correct for self-absorption, a partial least squares model with R<sup>2</sup> of 0.9995, resulted in an accuracy of the Root Mean Squared Error of Prediction for Beta Carotene of 0.0032 mg/mL and Limit of Detection 0.0106 mg/mL. Principal Components Analysis clearly differentiated solutions of the three carotenoids, based primarily on small shifts of the main peak at ~1520 cm<sup>−1</sup>. Least squares fitting analysis of the spectra of admixtures of the carotenoid:protein complexes showed reasonable correlation between norminal% and fitted%, yielding 100% contribution when fitted with individual carotenoid complexes and variable contributions with multiple ratios of admixtures. The results indicate the technique can potentially be used to quantify the carotenoid content of human serum and to identify their differential contributions for application in clinical analysis.https://www.mdpi.com/1420-3049/27/15/4724carotenoidsBeta CaroteneLuteinZeaxanthinRaman spectroscopybovine serum albumin |
| spellingShingle | Joy Udensi Ekaterina Loskutova James Loughman Hugh J. Byrne Quantitative Raman Analysis of Carotenoid Protein Complexes in Aqueous Solution Molecules carotenoids Beta Carotene Lutein Zeaxanthin Raman spectroscopy bovine serum albumin |
| title | Quantitative Raman Analysis of Carotenoid Protein Complexes in Aqueous Solution |
| title_full | Quantitative Raman Analysis of Carotenoid Protein Complexes in Aqueous Solution |
| title_fullStr | Quantitative Raman Analysis of Carotenoid Protein Complexes in Aqueous Solution |
| title_full_unstemmed | Quantitative Raman Analysis of Carotenoid Protein Complexes in Aqueous Solution |
| title_short | Quantitative Raman Analysis of Carotenoid Protein Complexes in Aqueous Solution |
| title_sort | quantitative raman analysis of carotenoid protein complexes in aqueous solution |
| topic | carotenoids Beta Carotene Lutein Zeaxanthin Raman spectroscopy bovine serum albumin |
| url | https://www.mdpi.com/1420-3049/27/15/4724 |
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