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- Barimah, Alberta Osei, et al.
(författare)
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Sensitive label-free Cu2O/Ag fused chemometrics SERS sensor for rapid detection of total arsenic in tea
- 2021
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Ingår i: Food Control. - : Elsevier. - 0956-7135 .- 1873-7129. ; 130
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Tidskriftsartikel (refereegranskat)abstract
- Arsenic (As) is one of the toxic, persistent, and lethal heavy metalloids and requires rapid, less costly, and sensitive detection methods. This study proposed a label-free cuprous oxide/silver (Cu2O/Ag) surface-enhanced Raman scattering (SERS) nanoprobe to detect total As in tea. Different total As spiked tea concentrations were mixed with the Cu2O/Ag SERS nanoprobe for the SERS detection. Quantitative models were established for predicting the total As in tea by comparatively applying chemometric algorithms. Amongst the algorithms, competitive adaptive reweighted sampling partial least squares (CARS-PLS) optimized the most effective spectral variables to predict the total As in tea efficiently. The CARS-PLS gave the highest correlation coefficient value (R-p = 0.9935), very low root means square error (RMSEP = 0.0496 mu g g(-1)) in the prediction set and recorded the highest RPD value of 8.819. The proposed nanoprobe achieved a lower detection limit (0.00561 mu g g(-1)), excellent selectivity, satisfactory reproducibility, and stability. No significant difference was recorded when the performance of the Cu2O/Ag total As SERS sensor was compared with the inductively coupled plasma mass spectrometry (ICP-MS) method. Therefore, this developed Cu2O/Ag coupled chemometrics SERS sensing method could be used to efficiently determine, quantify, and predict total As in tea to promote monitoring of heavy metal contaminants.
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| 2. |
- Guo, Zhiming, et al.
(författare)
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Chemometrics coupled 4-Aminothiophenol labelled Ag-Au alloy SERS off-signal nanosensor for quantitative detection of mercury in black tea
- 2020
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Ingår i: Spectrochimica Acta Part A - Molecular and Biomolecular Spectroscopy. - : Elsevier BV. - 1386-1425 .- 1873-3557. ; 242
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Tidskriftsartikel (refereegranskat)abstract
- Black tea like other food crops is prone to mercury ion (Hg2+) contamination right from cultivation to industrial processing. Due to the dangerous health effects posed even in trace contents, sensitive detection and quantification sensors are required. This study employed the surface-enhanced Raman scattering (SERS) enhancement property of 4-aminothiophenol (4-ATP) as a signal turn off approach functionalized on Ag-Au alloyed nanopartide to firstly detect Hg2+ in standard solutions and spiked tea samples. Different chemometric algorithms were applied on the acquired SERS and inductively coupled plasma-mass spectrometry (ICP-MS) chemical reference data to select effective wavelengths and spectral variables in order to develop models to predict the Hg2+. Results indicated that Ag-Au/4-ATP SERS sensor combined with ant colony optimization partial least squares (ACO-PLS) exhibited the best correlation efficient and minimum errors for Hg2+ standard solutions (R-c = 0.984, R-p = 0.974, RMSEC = 0.157 mu g/mL, RMSEP = 0.211 mu g/mL) and spiked tea samples (R-c = 0.979, R-p = 0.963, RMSEC = 0.181 mu g/g and RMSEP = 0210 mu g/g). The limit of detection of the proposed sensor was 4.12 x 10(-7) mu g/mL for Hg2+ standard solutions and 2.83 x 10(-5) mu g/g for Hg2+ spiked tea samples. High stability and reproducibility with relative standard deviation of 1.14% and 0.84% were detected. The potent strong relationship between the SERS sensor and the chemical reference method encourages the application of the developed chemometrics coupled SERS system for future monitoring and evaluation of Hg2+ in tea.
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