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Forchetti DA, Poppi RJ. Use of NIR hyperspectral imaging and multivariate curve resolution (MCR) for detection and quantification of adulterants in milk powder. Lebensm Wiss Technol 2017. [DOI: 10.1016/j.lwt.2016.06.046] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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27
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Villa JEL, Poppi RJ. A portable SERS method for the determination of uric acid using a paper-based substrate and multivariate curve resolution. Analyst 2017; 141:1966-72. [PMID: 26844706 DOI: 10.1039/c5an02398j] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This paper presents a portable quantitative method for the on-site determination of uric acid in urine using surface-enhanced Raman spectroscopy (SERS) and gold nanoparticle-coated paper as a substrate. A procedure was developed for the rapid preparation of cost-effective SERS substrates that enabled the adequate control of a homogeneous active area and the use of small quantities of gold nanoparticles per substrate. The standard addition method and multivariate curve resolution-alternating least squares (MCR-ALS) were applied to compensate for the matrix effect and to address overlapping bands between uric acid and interference SERS spectra. The proposed methodology demonstrated better performance than conventional univariate methods (in terms of linearity, accuracy and precision), a wide linear range (0-3.5 mmol L(-1)) and an adequate limit of detection (0.11 mmol L(-1)). For the first time, a portable SERS method coupled with chemometrics was developed for the routine analysis of uric acid at clinically relevant concentrations with minimal sample preparation and easy extension for the on-site determination of other biomarkers in complex sample matrices.
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Almeida GB, Poppi RJ, da Silva JAF. Trapping of Au nanoparticles in a microfluidic device using dielectrophoresis for surface enhanced Raman spectroscopy. Analyst 2017; 142:375-379. [DOI: 10.1039/c6an01497f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper, we use DEP with insulating structures (iDEP) to generate a non-uniform electric field for trapping gold nanoparticles (AuNP). The system was coupled to a Raman spectrometer for the detection of Crystal Violet by utilizing the SERS effect.
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Oliveira LF, Braga SC, Augusto F, Hashimoto JC, Efraim P, Poppi RJ. Differentiation of cocoa nibs from distinct origins using comprehensive two-dimensional gas chromatography and multivariate analysis. Food Res Int 2016; 90:133-138. [DOI: 10.1016/j.foodres.2016.10.047] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 10/25/2016] [Accepted: 10/29/2016] [Indexed: 12/17/2022]
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30
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Caramês ETS, Alamar PD, Poppi RJ, Pallone JAL. Rapid Assessment of Total Phenolic and Anthocyanin Contents in Grape Juice Using Infrared Spectroscopy and Multivariate Calibration. FOOD ANAL METHOD 2016. [DOI: 10.1007/s12161-016-0721-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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31
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Kawahara R, Meirelles GV, Heberle H, Domingues RR, Granato DC, Yokoo S, Canevarolo RR, Winck FV, Ribeiro ACP, Brandão TB, Filgueiras PR, Cruz KSP, Barbuto JA, Poppi RJ, Minghim R, Telles GP, Fonseca FP, Fox JW, Santos-Silva AR, Coletta RD, Sherman NE, Paes Leme AF. Integrative analysis to select cancer candidate biomarkers to targeted validation. Oncotarget 2016; 6:43635-52. [PMID: 26540631 PMCID: PMC4791256 DOI: 10.18632/oncotarget.6018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 10/17/2015] [Indexed: 01/15/2023] Open
Abstract
Targeted proteomics has flourished as the method of choice for prospecting for and validating potential candidate biomarkers in many diseases. However, challenges still remain due to the lack of standardized routines that can prioritize a limited number of proteins to be further validated in human samples. To help researchers identify candidate biomarkers that best characterize their samples under study, a well-designed integrative analysis pipeline, comprising MS-based discovery, feature selection methods, clustering techniques, bioinformatic analyses and targeted approaches was performed using discovery-based proteomic data from the secretomes of three classes of human cell lines (carcinoma, melanoma and non-cancerous). Three feature selection algorithms, namely, Beta-binomial, Nearest Shrunken Centroids (NSC), and Support Vector Machine-Recursive Features Elimination (SVM-RFE), indicated a panel of 137 candidate biomarkers for carcinoma and 271 for melanoma, which were differentially abundant between the tumor classes. We further tested the strength of the pipeline in selecting candidate biomarkers by immunoblotting, human tissue microarrays, label-free targeted MS and functional experiments. In conclusion, the proposed integrative analysis was able to pre-qualify and prioritize candidate biomarkers from discovery-based proteomics to targeted MS.
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32
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Albuquerque CDL, Nogueira RB, Poppi RJ. Determination of 17β-estradiol and noradrenaline in dog serum using surface-enhanced Raman spectroscopy and random Forest. Microchem J 2016. [DOI: 10.1016/j.microc.2016.04.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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33
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Setti GO, Joanni E, Poppi RJ, Dos Santos DP, Jesus DPD. Temporal drift in Raman signal intensity during SERS measurements performed on analytes in liquid solutions. Analyst 2016; 141:5071-7. [PMID: 27471752 DOI: 10.1039/c6an00876c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
In this communication, we report one factor that could limit the quantitative analysis by SERS, which has not yet been discussed in the literature. Our results show that SERS experiments performed with the substrate immersed in liquid solutions are subjected to a temporal drift in the Raman signal intensity. Measurements were performed using gold nanoparticle suspensions and gold-covered nanostructured ITO surfaces as SERS substrates, immersed in analyte solutions of crystal violet and 4-mercaptobenzoic acid. Depending on the substrate and the conditions used for measurements, the Raman signal can take between 30 min and several hours to stabilize. This effect, if not taken into account, could have a negative impact on the results of the quantitative chemical analysis by SERS performed in situ in liquid solutions.
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Pontes JGM, Ohashi WY, Brasil AJM, Filgueiras PR, Espíndola APDM, Silva JS, Poppi RJ, Coletta-Filho HD, Tasic L. Metabolomics by NMR Spectroscopy in Plant Disease diagnostic: Huanglongbing as a Case Study. ChemistrySelect 2016. [DOI: 10.1002/slct.201600064] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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35
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Alamar PD, Caramês ETS, Poppi RJ, Pallone JAL. Quality evaluation of frozen guava and yellow passion fruit pulps by NIR spectroscopy and chemometrics. Food Res Int 2016; 85:209-214. [PMID: 29544837 DOI: 10.1016/j.foodres.2016.04.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 04/21/2016] [Accepted: 04/24/2016] [Indexed: 10/21/2022]
Abstract
The present study investigated the application of near infrared spectroscopy as a green, quick, and efficient alternative to analytical methods currently used to evaluate the quality (moisture, total sugars, acidity, soluble solids, pH and ascorbic acid) of frozen guava and passion fruit pulps. Fifty samples were analyzed by near infrared spectroscopy (NIR) and reference methods. Partial least square regression (PLSR) was used to develop calibration models to relate the NIR spectra and the reference values. Reference methods indicated adulteration by water addition in 58% of guava pulp samples and 44% of yellow passion fruit pulp samples. The PLS models produced lower values of root mean squares error of calibration (RMSEC), root mean squares error of prediction (RMSEP), and coefficient of determination above 0.7. Moisture and total sugars presented the best calibration models (RMSEP of 0.240 and 0.269, respectively, for guava pulp; RMSEP of 0.401 and 0.413, respectively, for passion fruit pulp) which enables the application of these models to determine adulteration in guava and yellow passion fruit pulp by water or sugar addition. The models constructed for calibration of quality parameters of frozen fruit pulps in this study indicate that NIR spectroscopy coupled with the multivariate calibration technique could be applied to determine the quality of guava and yellow passion fruit pulp.
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Godinho RB, Santos MC, Poppi RJ. Determination of fragrance content in perfume by Raman spectroscopy and multivariate calibration. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2016; 157:158-163. [PMID: 26771246 DOI: 10.1016/j.saa.2015.12.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 12/15/2015] [Accepted: 12/20/2015] [Indexed: 06/05/2023]
Abstract
An alternative methodology is herein proposed for determination of fragrance content in perfumes and their classification according to the guidelines established by fine perfume manufacturers. The methodology is based on Raman spectroscopy associated with multivariate calibration, allowing the determination of fragrance content in a fast, nondestructive, and sustainable manner. The results were considered consistent with the conventional method, whose standard error of prediction values was lower than the 1.0%. This result indicates that the proposed technology is a feasible analytical tool for determination of the fragrance content in a hydro-alcoholic solution for use in manufacturing, quality control and regulatory agencies.
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de Souza LM, Rodrigues RR, Santos H, Costa HB, Merlo BB, Filgueiras PR, Poppi RJ, Vaz BG, Romão W. A survey of adulterants used to cut cocaine in samples seized in the Espírito Santo State by GC–MS allied to chemometric tools. Sci Justice 2016; 56:73-9. [DOI: 10.1016/j.scijus.2015.11.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 11/16/2015] [Accepted: 11/20/2015] [Indexed: 11/29/2022]
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38
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Filgueiras PR, Terra LA, Castro EV, Oliveira LM, Dias JC, Poppi RJ. Prediction of the distillation temperatures of crude oils using 1H NMR and support vector regression with estimated confidence intervals. Talanta 2015; 142:197-205. [DOI: 10.1016/j.talanta.2015.04.046] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/13/2015] [Accepted: 04/16/2015] [Indexed: 10/23/2022]
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39
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Almeida MR, Correa DN, Zacca JJ, Logrado LPL, Poppi RJ. Detection of explosives on the surface of banknotes by Raman hyperspectral imaging and independent component analysis. Anal Chim Acta 2015; 860:15-22. [DOI: 10.1016/j.aca.2014.12.034] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 12/15/2014] [Accepted: 12/17/2014] [Indexed: 10/24/2022]
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40
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Oliveira LF, Braga SC, Filgueiras PR, Augusto F, Poppi RJ. Assessment of robustness on analysis using headspace solid-phase microextraction and comprehensive two-dimensional gas chromatography through experimental designs. Talanta 2014; 129:303-8. [DOI: 10.1016/j.talanta.2014.05.038] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 05/19/2014] [Accepted: 05/20/2014] [Indexed: 02/06/2023]
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41
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Alexandrino GL, Poppi RJ. Study of the homogeneity of drug loaded in polymeric films using near-infrared chemical imaging and split-plot design. J Pharm Sci 2014; 103:2356-65. [PMID: 24961172 DOI: 10.1002/jps.24051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 05/20/2014] [Accepted: 05/21/2014] [Indexed: 11/10/2022]
Abstract
Split-plot design (SPD) and near-infrared chemical imaging were used to study the homogeneity of the drug paracetamol loaded in films and prepared from mixtures of the biocompatible polymers hydroxypropyl methylcellulose, polyvinylpyrrolidone, and polyethyleneglycol. The study was split into two parts: a partial least-squares (PLS) model was developed for a pixel-to-pixel quantification of the drug loaded into films. Afterwards, a SPD was developed to study the influence of the polymeric composition of films and the two process conditions related to their preparation (percentage of the drug in the formulations and curing temperature) on the homogeneity of the drug dispersed in the polymeric matrix. Chemical images of each formulation of the SPD were obtained by pixel-to-pixel predictions of the drug using the PLS model of the first part, and macropixel analyses were performed for each image to obtain the y-responses (homogeneity parameter). The design was modeled using PLS regression, allowing only the most relevant factors to remain in the final model. The interpretation of the SPD was enhanced by utilizing the orthogonal PLS algorithm, where the y-orthogonal variations in the design were separated from the y-correlated variation.
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42
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Alves JCL, Henriques CB, Poppi RJ. Classification of diesel pool refinery streams through near infrared spectroscopy and support vector machines using C-SVC and ν-SVC. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 117:389-396. [PMID: 24012979 DOI: 10.1016/j.saa.2013.08.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 07/29/2013] [Accepted: 08/03/2013] [Indexed: 06/02/2023]
Abstract
The use of near infrared (NIR) spectroscopy combined with chemometric methods have been widely used in petroleum and petrochemical industry and provides suitable methods for process control and quality control. The algorithm support vector machines (SVM) has demonstrated to be a powerful chemometric tool for development of classification models due to its ability to nonlinear modeling and with high generalization capability and these characteristics can be especially important for treating near infrared (NIR) spectroscopy data of complex mixtures such as petroleum refinery streams. In this work, a study on the performance of the support vector machines algorithm for classification was carried out, using C-SVC and ν-SVC, applied to near infrared (NIR) spectroscopy data of different types of streams that make up the diesel pool in a petroleum refinery: light gas oil, heavy gas oil, hydrotreated diesel, kerosene, heavy naphtha and external diesel. In addition to these six streams, the diesel final blend produced in the refinery was added to complete the data set. C-SVC and ν-SVC classification models with 2, 4, 6 and 7 classes were developed for comparison between its results and also for comparison with the soft independent modeling of class analogy (SIMCA) models results. It is demonstrated the superior performance of SVC models especially using ν-SVC for development of classification models for 6 and 7 classes leading to an improvement of sensitivity on validation sample sets of 24% and 15%, respectively, when compared to SIMCA models, providing better identification of chemical compositions of different diesel pool refinery streams.
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43
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Terra LA, Filgueiras PR, Tose LV, Romão W, de Souza DD, de Castro EVR, de Oliveira MSL, Dias JCM, Poppi RJ. Petroleomics by electrospray ionization FT-ICR mass spectrometry coupled to partial least squares with variable selection methods: prediction of the total acid number of crude oils. Analyst 2014; 139:4908-16. [DOI: 10.1039/c4an00538d] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
FT-ICR MS coupled to PLS regression in petroleomics.
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Conceição VN, Souza LM, Merlo BB, Filgueiras PR, Poppi RJ, Romão W. STUDY OF SCOTT TEST USING SPECTROSCOPIC TECHNIQUES: AN ALTERNATIVE METHOD FOR DETECTING COCAINE HYDROCHLORIDE AND ITS ADDULTERANTS IN STREET DRUGS. QUIM NOVA 2014. [DOI: 10.5935/0100-4042.20140240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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45
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Almeida MR, Fidelis CH, Barata LE, Poppi RJ. Classification of Amazonian rosewood essential oil by Raman spectroscopy and PLS-DA with reliability estimation. Talanta 2013; 117:305-11. [DOI: 10.1016/j.talanta.2013.09.025] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 08/09/2013] [Accepted: 09/17/2013] [Indexed: 11/29/2022]
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46
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Sabin GP, Lozano VA, Rocha WF, Romão W, Ortiz RS, Poppi RJ. Characterization of sildenafil citrate tablets of different sources by near infrared chemical imaging and chemometric tools. J Pharm Biomed Anal 2013; 85:207-12. [DOI: 10.1016/j.jpba.2013.07.036] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 07/26/2013] [Accepted: 07/29/2013] [Indexed: 10/26/2022]
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47
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de Almeida MR, Correa DN, Rocha WF, Scafi FJ, Poppi RJ. Discrimination between authentic and counterfeit banknotes using Raman spectroscopy and PLS-DA with uncertainty estimation. Microchem J 2013. [DOI: 10.1016/j.microc.2012.03.006] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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48
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Kowalski CH, da Silva GA, Godoy HT, Poppi RJ, Augusto F. Application of Kohonen neural network for evaluation of the contamination of Brazilian breast milk with polychlorinated biphenyls. Talanta 2013; 116:315-21. [PMID: 24148409 DOI: 10.1016/j.talanta.2013.05.033] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 05/13/2013] [Accepted: 05/16/2013] [Indexed: 11/29/2022]
Abstract
Due to the tendency of polychlorinated biphenyls (PCB) to accumulate in matrixes with high lipid content, the contamination of the breast milk with these compounds is a serious issue, mainly to the newborn. In this study, milk samples were collected from breastfeeding mothers belonging to 4 Brazilian regions (south, southeast, northeast and north). Twelve PCB were analyzed by HS-SPME-GC-ECD and the corresponding peak areas were correlated to the answers to a questionnaire of general habits, breastfeeding and characteristics of the living places. To realize this exploratory analyze, self-organizing maps generated applying Kohonen neural network were applied. It was possible to verify the occurrence of different PCB congeners in the breast milk relating to the region of the Brazil that the breastfeeding lives, the proximity to an industry, the proximity to a contaminated river or sea, the type of milk (colostrum, foremilk and hindmilk) and the number of past pregnancies.
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Alves JCL, Poppi RJ. Pharmaceutical analysis in solids using front face fluorescence spectroscopy and multivariate calibration with matrix correction by piecewise direct standardization. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 103:311-318. [PMID: 23261628 DOI: 10.1016/j.saa.2012.10.074] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 10/29/2012] [Accepted: 10/31/2012] [Indexed: 06/01/2023]
Abstract
This paper reports the application of piecewise direct standardization (PDS) for matrix correction in front face fluorescence spectroscopy of solids when different excipients are used in a pharmaceutical preparation based on a mixture of acetylsalicylic acid (ASA), paracetamol (acetaminophen) and caffeine. As verified in earlier studies, the use of different excipients and their ratio can cause a displacement, change in fluorescence intensity or band profile. To overcome this important drawback, a standardization strategy was adopted to convert all the excitation-emission fluorescence spectra into those used for model development. An excitation-emission matrix (EEM) for which excitation and emission wavelengths ranging from 265 to 405 nm and 300 to 480 nm, respectively, was used. Excellent results were obtained using unfolded partial least squares (U-PLS), with RMSEP values of 8.2 mg/g, 10.9 mg/g and 2.7 mg/g for ASA, paracetamol and caffeine, respectively, and with relative errors lesser than 5% for the three analytes.
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50
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Alexandrino GL, Poppi RJ. NIR imaging spectroscopy for quantification of constituents in polymers thin films loaded with paracetamol. Anal Chim Acta 2013; 765:37-44. [DOI: 10.1016/j.aca.2012.12.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 11/12/2012] [Accepted: 12/11/2012] [Indexed: 10/27/2022]
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