{"title":"Simultaneous Determination of Ternary Mixture of Carboxin, Chlorpyrifos, and Tebuconazole Residues in Cabbage Samples Using Three Spectrophotometric Methods","authors":"S. A. Omer, Nabil A. Fakhre","doi":"10.1155/2020/4912762","DOIUrl":"https://doi.org/10.1155/2020/4912762","url":null,"abstract":"Three simple precise and accurate spectrophotometric methods are developed for simultaneous determination of ternary mixtures of carboxin, chlorpyrifos, and tebuconazole residues in cabbage grown in the experimental field. The first method is a double divisor-ratio spectra derivative that relies on the derivative of ratio spectra and attained through dividing the absorption spectra of the ternary mixture by the sum of standard spectrum of a mixture of two from three components, using methanol as a solvent and measuring CAR at 242 nm, CHL at 236 nm, 276 nm, and 300 nm, and TEB at 226 nm. The second method is a successive derivative of ratio spectra which determined CAR at 256 nm and 258 nm, CHL at 290 nm and 292 nm, and TEB at 226 nm and 228 nm. The third method is a mean centering of ratio spectra where CAR, CHL, and TEB were measured at 306 nm, 280 nm, and 240 nm, respectively. These procedures do not involve any previous separation. The extraction of analytes was carried out by using acetonitrile, and the procedure of purification was fulfilled by dispersive solid-phase extraction with a primary-secondary amine (PSA). The proposed methods showed excellent linearity range for three spectrophotometric methods over the concentration ranges of 1–30 μg/mL, 1–50 μg/mL, and 1–45 μg/mL for carboxin, chlorpyrifos, and tebuconazole, respectively. The analytical characteristics such as detection limit, determination limit, relative standard deviation, and accuracy of the three methods were performed. The limits of detection were in the range of 0.153–0.260 μg/mL for carboxin, 0.137–0.272 μg/mL for chlorpyrifos, and 0.109–0.205 μg/mL for tebuconazole with limits of quantification lower than 0.790, 0.824, and 0.621 μg/mL for CAR, CHL, and TEB, respectively. The recoveries ranged from 87.02% to 94.53% for carboxin, 92.32% to 108.53% for chlorpyrifos, and 87.19% to 98.00% for tebuconazole with relative standard deviations less than 5.91%, 5.99%, and 5.53% in all instances for carboxin, chlorpyrifos, and tebuconazole, respectively. The results obtained from the proposed methods were compared statistically by using one-way ANOVA, and the results revealed that there were no significant differences between three different spectrophotometric methods. The suggested methods can be applied with great success to the simultaneous estimation of carboxin, chlorpyrifos, and tebuconazole residues in cabbage samples.","PeriodicalId":15248,"journal":{"name":"Journal of Automated Methods & Management in Chemistry","volume":"79 1-2 1","pages":"1-16"},"PeriodicalIF":0.0,"publicationDate":"2020-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77853986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Novel Sandwich Electrochemical Immunosensor Based on the DNA-Derived Magnetic Nanochain Probes for Alpha-Fetoprotein.","authors":"Ning Gan, Liyong Jia, Lei Zheng","doi":"10.1155/2011/957805","DOIUrl":"https://doi.org/10.1155/2011/957805","url":null,"abstract":"<p><p>One novel electrochemical immunosensor was constructed by immobilizing capture antibody of alpha-fetoprotein (AFP Ab(1)) on a nafion/nanogold-particle modified glassy carbon electrode. With a sandwich immunoassay, one DNA-derived magnetic nanoprobe, simplified as DNA/(ZMPs-HRP-AFP Ab(2))(n), was employed for the detection of AFP. The fabricated procedure of the proposed biosensor was characterized by cyclic voltammetry and electrochemical impedance spectroscopy. The performance and factors influencing the performance of the biosensor were also evaluated. Under optimal conditions, the developed biosensor exhibited a well-defined electrochemical behavior toward the reduction of AFP ranging from 0.01 to 200 ng/mL with a detection limit of 4 pg/mL (S/N = 3). The biosensor was applied to the determination of AFP in serum with satisfactory results. It is important to note that the sandwich nanochainmodified electro-immunosensor provided an alternative substrate for the immobilization of other tumor markers.</p>","PeriodicalId":15248,"journal":{"name":"Journal of Automated Methods & Management in Chemistry","volume":"2011 ","pages":"957805"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2011/957805","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30075411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fractionation of volatile constituents from curcuma rhizome by preparative gas chromatography.","authors":"F Q Yang, H K Wang, H Chen, J D Chen, Z N Xia","doi":"10.1155/2011/942467","DOIUrl":"https://doi.org/10.1155/2011/942467","url":null,"abstract":"<p><p>A preparative gas chromatography (pGC) method was developed for the separation of volatile components from the methanol extract of Curcuma rhizome. The compounds were separated on a stainless steel column packed with 10% OV-101 (3 m × 6 mm, i.d.), and then, the effluent was split into two gas flows. One percent of the effluent passed to the flame ionization detector (FID) for detection and the remaining 99% were directed to the fraction collector. Five volatile compounds were collected from the methanol extract of Curcuma rhizome (5 g/mL) after 83 single injections (20 uL) with the yield of 5.1-46.2 mg. Furthermore, the structures of the obtained compounds were identified as β-elemene, curzerene, curzerenone, curcumenol, and curcumenone by MS and NMR spectra, respectively.</p>","PeriodicalId":15248,"journal":{"name":"Journal of Automated Methods & Management in Chemistry","volume":"2011 ","pages":"942467"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2011/942467","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30106639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jumat Salimon, Neeranjini Nallathamby, Nadia Salih, Bashar Mudhaffar Abdullah
{"title":"Synthesis and physical properties of estolide ester using saturated Fatty Acid and ricinoleic Acid.","authors":"Jumat Salimon, Neeranjini Nallathamby, Nadia Salih, Bashar Mudhaffar Abdullah","doi":"10.1155/2011/263624","DOIUrl":"https://doi.org/10.1155/2011/263624","url":null,"abstract":"<p><p>A study was conveyed to produce estolide ester using ricinoleic acid as the backbone. The ricinoleic acid reacted with saturated fatty acid from C8-C18. These reactions were conducted under vacuum at 60°C for 24 h without solvent. The reaction used acid catalyst, sulphuric acid. The new saturate ricinoleic estolide esters show superior low-temperature properties (-52 ± 0.08°C) and high flash point (>300°C). The yield of the neat estolide esters ranged from 52% to 96%. The viscosity range was 51 ± 0.08 to 86 ± 0.01 cp. These new saturated estolide esters were also compared with saturated branched estolide esters.</p>","PeriodicalId":15248,"journal":{"name":"Journal of Automated Methods & Management in Chemistry","volume":"2011 ","pages":"263624"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2011/263624","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30215685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Erratum: to \"Development of a Low-Cost SIA-Based Analyser for Water Samples\".","authors":"Moisés Knochen, Alejandro Caamaño, Heinkel Bentos","doi":"10.1155/2011/418910","DOIUrl":"https://doi.org/10.1155/2011/418910","url":null,"abstract":"We are hereby presenting an erratum to our paper \" Development of a Low-Cost SIA-Based Analyser for Water Samples. \" We have noticed an error in Table 1: units for concentrations were erroneously labelled as μg L −1 , when in fact they should be labelled as mg L −1. The corrected version of Table 1 is presented. Table 1: Analytical figures of merit for the automated methods developed for chloride, nitrite, and nitrate in water samples. LD and LQ: detection (3σ) and quantification (10σ) limits. Precision was measured as repeatability (n = 10).","PeriodicalId":15248,"journal":{"name":"Journal of Automated Methods & Management in Chemistry","volume":"2011 ","pages":"418910"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2011/418910","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30045049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quantitative determination of acetaldehyde in foods using automated digestion with simulated gastric fluid followed by headspace gas chromatography.","authors":"Michael Uebelacker, Dirk W Lachenmeier","doi":"10.1155/2011/907317","DOIUrl":"10.1155/2011/907317","url":null,"abstract":"<p><p>Acetaldehyde (ethanal) is a genotoxic carcinogen, which may occur naturally or as an added flavour in foods. We have developed an efficient method to analyze the compound in a wide variety of food matrices. The analysis is conducted using headspace (HS) gas chromatography (GC) with flame ionization detector. Using a robot autosampler, the samples are digested in full automation with simulated gastric fluid (1 h at 37°C) under shaking, which frees acetaldehyde loosely bound to matrix compounds. Afterwards, an aliquot of the HS is injected into the GC system. Standard addition was applied for quantification to compensate for matrix effects. The precision of the method was sufficient (<3% coefficient of variation). The limit of detection was 0.01 mg/L and the limit of quantification was 0.04 mg/L. 140 authentic samples were analyzed. The acetaldehyde content in apples was 0.97 ± 0.80 mg/kg, orange juice contained 3.86 ± 2.88 mg/kg. The highest concentration was determined in a yoghurt (17 mg/kg). A first-exposure estimation resulted in a daily acetaldehyde intake of less than 0.1 mg/kg bodyweight from food, which is considerably lower than the exposures from alcohol consumption or tobacco smoking.</p>","PeriodicalId":15248,"journal":{"name":"Journal of Automated Methods & Management in Chemistry","volume":"2011 ","pages":"907317"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3124883/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"29999355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Determination of potassium, sodium, and total alkalies in portland cement, fly ash, admixtures, and water of concrete by a simple flow injection flame photometric system.","authors":"Jaroon Junsomboon, Jaroon Jakmunee","doi":"10.1155/2011/742656","DOIUrl":"https://doi.org/10.1155/2011/742656","url":null,"abstract":"<p><p>A simple flow injection with flame photometric detection has been developed for determination of sodium, potassium, and total alkalies in portland cement, fly ash, admixtures, and water of concrete. A liquid sample or a digest of solid sample was injected into a water carrier stream which flowed to a flame photometer. A change in emission intensity at a selected wavelength was recorded as a peak. An amplifier circuit was fabricated, which helped improve sensitivity of the flame photometer. Calibration graphs in the range of 0.05-1.0 mg L(-1) and 1.0-20.0 mg L(-1) were obtained with a detection limit of 0.02 mg L(-1), for both potassium and sodium determination. Relative standard deviations for 11 replicates of injecting of 10 mg L(-1) potassium and sodium solutions were 1.69 and 1.79%, respectively. Sample throughput of 120 h(-1) was achieved. The proposed method was successfully applied to portland cement, fly ash, admixtures, and water samples validated by the ASTM standard method and certified reference materials of portland cement.</p>","PeriodicalId":15248,"journal":{"name":"Journal of Automated Methods & Management in Chemistry","volume":"2011 ","pages":"742656"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2011/742656","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"29998880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vanessa N Alves, Simone S O Borges, Waldomiro B Neto, Nívia M M Coelho
{"title":"Determination of low levels of lead in beer using solid-phase extraction and detection by flame atomic absorption spectrometry.","authors":"Vanessa N Alves, Simone S O Borges, Waldomiro B Neto, Nívia M M Coelho","doi":"10.1155/2011/464102","DOIUrl":"https://doi.org/10.1155/2011/464102","url":null,"abstract":"<p><p>In this study, a method for the determination of low concentrations of lead in beer samples using solid-phase extraction with a flow injection analysis system and detection by flame atomic absorption spectrometry (FAAS) was developed. Moringa oleifera seeds were used as a biosorbent material. Chemical and flow variables of the online preconcentration system, such as sample pH, preconcentration flow rate, eluent flow rate, eluent concentration, particle size, and sorbent mass, were studied. The optimum extraction conditions were obtained using a sample pH of 6.0, sample flow rate of 6.0 mL min(-1), 63.0 mg of sorbent mass, and 2.0 mol L(-1) HNO(3) at a flow rate of 2.0 mL min(-1) as the eluent. With the optimized conditions, the preconcentration factor, precision, detection limit, consumption index, and sample throughput were estimated as 93, 0.3% (10.0 μg L(-1), n = 7), 7.5 μg L(-1), 0.11 mL, and 23 samples per hour, respectively. The method developed was successfully applied to beer samples and recovery tests, with recovery ranging from 80% to 100%.</p>","PeriodicalId":15248,"journal":{"name":"Journal of Automated Methods & Management in Chemistry","volume":"2011 ","pages":"464102"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2011/464102","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30075410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Determination of trace silver in water samples by online column preconcentration flame atomic absorption spectrometry using termite digestion product.","authors":"Joyce Nunes Bianchin, Edmar Martendal, Eduardo Carasek","doi":"10.1155/2011/839365","DOIUrl":"https://doi.org/10.1155/2011/839365","url":null,"abstract":"<p><p>A new method for Ag determination in water samples using solid phase extraction (SPE) coupled to a flow injection system and flame atomic absorption spectrometry was developed. The sorbent used for Ag preconcentration and extraction was the termite digestion product. Flow and chemical variables of the system were optimized through a multivariate procedure. The factors selected were adsorbent mass, buffer type and concentration, sample pH, and sample flow rate. The detection limit and precision were 3.4 μg L(-1) and 3.8% (n = 6, 15 μg L(-1)), respectively. The enrichment factor and the linear working range were, respectively, 21 and 10-50 μg L(-1). Results for recovery tests using different water samples were between 96 and 107%. The proposed methodology was applied with success for the determination of Ag in water used to wash clothes impregnated with silver nanoparticles, supplied by a factory located in Santa Catarina, Brazil.</p>","PeriodicalId":15248,"journal":{"name":"Journal of Automated Methods & Management in Chemistry","volume":"2011 ","pages":"839365"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2011/839365","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30044863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A LabVIEW-Based Virtual Instrument System for Laser-Induced Fluorescence Spectroscopy.","authors":"Qijun Wu, Lufei Wang, Lily Zu","doi":"10.1155/2011/457156","DOIUrl":"https://doi.org/10.1155/2011/457156","url":null,"abstract":"<p><p>We report the design and operation of a Virtual Instrument (VI) system based on LabVIEW 2009 for laser-induced fluorescence experiments. This system achieves synchronous control of equipment and acquisition of real-time fluorescence data communicating with a single computer via GPIB, USB, RS232, and parallel ports. The reported VI system can also accomplish data display, saving, and analysis, and printing the results. The VI system performs sequences of operations automatically, and this system has been successfully applied to obtain the excitation and dispersion spectra of α-methylnaphthalene. The reported VI system opens up new possibilities for researchers and increases the efficiency and precision of experiments. The design and operation of the VI system are described in detail in this paper, and the advantages that this system can provide are highlighted.</p>","PeriodicalId":15248,"journal":{"name":"Journal of Automated Methods & Management in Chemistry","volume":"2011 ","pages":"457156"},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2011/457156","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30220965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}