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Seyfi Mazraeno M, Fazlali A, Hosseini SN. Application of hydrocyclone for separation of Pichia pastoris produced r-HBsAg from fermentation culture: impact of concentration and pressure on hydrocyclone performance. Prep Biochem Biotechnol 2019; 49:813-821. [PMID: 31169457 DOI: 10.1080/10826068.2019.1621891] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Separation of biomass from culture media by centrifugation and then washing the biomass are mandatory steps in the fermentation process of recombinant Pichia pastoris expressed HBsAg intracellularly. Biomass has to be washed many times to eliminate the culture media residues thoroughly. In this study, we tried to develop the hydrocyclone as an alternative method for separation of biomass from fermentation culture, an attractive replacement for centrifugation processes. The advantages of using hydrocyclone in biomass separation could be summarized in its suitability for continuous separation and its low risk of contamination. To evaluate the performance of hydrocyclone, concentration ratio in underflow to feed stream, capacity, and centrifugal force by considering three parameters of pressure drop, concentration, and the type of hydrocyclone were investigated. Using three level factorial design a concentration ratio equation was developed, with the correlation coefficient R2 = 0.977 ensured the good fitness of the predicted data with the experimental results. In optimal conditions, maximum concentration ratio was 1.246, for flow rate 13.5 LPM and C-force equal to 1276.11 at maximum pressure drop (3 bar) and minimum concentration (0.5% w/w) in hydrocyclone 1. Herein, two different hydrocyclones with the cylindrical diameters of 19 mm and 21 mm were used for separating the yeast cells.
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Affiliation(s)
| | - Alireza Fazlali
- a Department of Chemical Engineering, Arak University , Arak , Iran
| | - Seyed Nezamedin Hosseini
- b Department of Hepatitis B vaccine Production, Production and Research, Complex Pasteur Institute of Iran , Tehran , Iran
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2
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Naeiji P, Varaminian F. Kinetic study of carbon dioxide hydrate formation by thermal analysis in the presence of two surfactants: Sodium dodecyl sulfate (SDS) and lauryl alcohol ethoxylate (LAE). J Mol Liq 2018. [DOI: 10.1016/j.molliq.2017.11.087] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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3
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Li L, Lai X, Xu X, Li J, Yuan P, Feng J, Wei L, Cheng X. Determination of bromate via the chemiluminescence generated in the sulfite and carbon quantum dot system. Mikrochim Acta 2018; 185:136. [PMID: 29594442 DOI: 10.1007/s00604-017-2653-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 12/29/2017] [Indexed: 10/18/2022]
Abstract
The authors describe a chemiluminescence (CL)-based assay for the determination of bromate. The method is based on the use of a solution of carbon quantum dots (CQDs) and sulfite. Strong CL (peak at 490 nm) is observed when bromate is injected into the solution. The CL increases linearly in the 0.3 to 10 μmol L-1 bromate concentration range, giving a 0.1 μmol L-1 limit of detection (at an S/N ratio of 3). A possible CL mechanism is suggested that involves a redox reaction between the CQDs, bromate and sulfite in the acidic medium. This leads to the formation of hole-injected and electron-injected CQDs. Radiative recombination of oxidant-injected holes and electrons in the CQDs accounts for the occurrence of CL. This mechanism contradicts the previous assumption that the transfer of energy occurs from SO2* to the CQDs. Although nitrite may interfere in the determination of bromate, its effect can be eliminated by adding sulfamic acid. The assay is sensitive and represents a new tool for the determination of bromate, which is a carcinogen. Graphical abstract Under acidic condition, carbon quantum dots (CQDs) can react with sulfite and bromate transforming to hole-injected CQDs (CQDs•-) and electron-injected CQDs (CQDs•+), respectively. Thereafter, strong chemiluminescence (490 nm) aroused from the radiative electron-hole annihilation between CQDs•- and CQDs•+.
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Affiliation(s)
- Liping Li
- Jiangxi Province Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, People's Republic of China.,School of Public Health, Nanchang University, 461 Bayi Road, Nanchang, 330006, People's Republic of China
| | - Xiaojing Lai
- Jiangxi Province Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, People's Republic of China.,School of Public Health, Nanchang University, 461 Bayi Road, Nanchang, 330006, People's Republic of China
| | - Xin Xu
- Jiangxi Province Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, People's Republic of China.,School of Public Health, Nanchang University, 461 Bayi Road, Nanchang, 330006, People's Republic of China
| | - Jie Li
- Jiangxi Province Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, People's Republic of China.,School of Public Health, Nanchang University, 461 Bayi Road, Nanchang, 330006, People's Republic of China
| | - Ping Yuan
- Jiangxi Province Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, People's Republic of China.,School of Public Health, Nanchang University, 461 Bayi Road, Nanchang, 330006, People's Republic of China
| | - Jiangao Feng
- Jiangxi Province Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, People's Republic of China.,School of Public Health, Nanchang University, 461 Bayi Road, Nanchang, 330006, People's Republic of China
| | - Lijun Wei
- Jiangxi Province Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, People's Republic of China. .,School of Public Health, Nanchang University, 461 Bayi Road, Nanchang, 330006, People's Republic of China.
| | - Xianglei Cheng
- Jiangxi Province Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, People's Republic of China. .,School of Public Health, Nanchang University, 461 Bayi Road, Nanchang, 330006, People's Republic of China.
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Crista DMA, Miranda MS, Esteves da Silva JCG. Degradation in chlorinated water of the UV filter 4-tert-butyl-4'-methoxydibenzoylmethane present in commercial sunscreens. ENVIRONMENTAL TECHNOLOGY 2015; 36:1319-1326. [PMID: 25399819 DOI: 10.1080/09593330.2014.988184] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
4-tert-Butyl-4'-methoxydibenzoylmethane (BMDM) is a widely used ultraviolet A filter. In this work, we have studied the effect of chlorine and dissolved organic matter (DOM) concentrations on the stability of UV filter (BMDM) present in two commercial sunscreen cream formulations in water. An experimental design was used to assess the effect of the two experimental factors on the degradation of BMDM. Higher concentrations of chlorine lead to higher degradation percentages of BMDM and higher concentrations of DOM inhibit its degradation. Moreover, a mono and a dichloro derivate of BMDM were identified as by-products.
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Affiliation(s)
- Diana M A Crista
- a Centro de Investigação em Química, Departamento de Química e Bioquímica, Faculdade de Ciências , Universidade do Porto , Porto , Portugal
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Al-Saidi HM, El-Shahawi MS. Extractive liquid-liquid spectrofluorometric determination of trace and ultra concentrations of bromate in water samples by the fluorescence quenching of tetraphenylphosphonium iodide. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 138:736-742. [PMID: 25544189 DOI: 10.1016/j.saa.2014.11.050] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 11/08/2014] [Accepted: 11/20/2014] [Indexed: 06/04/2023]
Abstract
A low cost and selective spectrofluorimetric method has been developed for trace determination of bromate ions in water. The method has been based upon complete extraction of the produced yellow colored ion associate of the reagent tetraphenylphosphonium iodide (TPP(+) I(-)) and bromate ions from aqueous media into chloroform and measuring the fluorescence quenching at λex/em=242/305nm. The composition, stability and the most probable mechanism of the produced associate have been determined. The plot of fluorescence intensity of TPP(+) I(-)vs. bromate concentration was linear in the range 0.86-150.0μgL(-1). The limits of detection (LOD) and quantification (LOQ) of BrO3(-) were 0.24 and 0.76μgL(-1), respectively. The method was found free from most of the interferences present in chromatographic, spectrofluorometric and spectrophotometric methods. Intra and inter-day laboratory accuracy and precision for analysis of bromate in water were determined. The method provides better performance compared to the international standard method recently issued (ISO 11206:2011). The method was applied satisfactorily for analysis of 1.0μgL(-1) bromate in the presence of high excess of chloride (50mg/L) without pretreatment with a relative standard deviation (RSD) of ±2.9%. The method was applied for analysis of bromate in various water samples. Statistical comparison of the results of the proposed method with those obtained by the standard method revealed no significant differences in the accuracy and precision.
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Affiliation(s)
- H M Al-Saidi
- Department of Chemistry, University College, Umm Al-Qura University, Makkah, Saudi Arabia.
| | - M S El-Shahawi
- Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
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Maznaya YI, Zuy OV, Vasilchuk TA, Goncharuk VV. Determination of bromate ions in waters by diffusion reflection spectroscopy. J WATER CHEM TECHNO+ 2014. [DOI: 10.3103/s1063455x14040043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Seyed Shahabadi SM, Reyhani A. Optimization of operating conditions in ultrafiltration process for produced water treatment via the full factorial design methodology. Sep Purif Technol 2014. [DOI: 10.1016/j.seppur.2014.04.051] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Rocha DL, Machado MC, Melchert WR. A sensitive flow-based procedure for spectrophotometric speciation analysis of inorganic bromine in waters. Talanta 2014; 129:93-9. [PMID: 25127569 DOI: 10.1016/j.talanta.2014.05.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 04/11/2014] [Accepted: 05/11/2014] [Indexed: 11/18/2022]
Abstract
A flow-based system with solenoid micro-pumps and long path-length spectrophotometry for bromate and bromide determination in drinking water is proposed. The method is based on the formation of an unstable dye from the reaction between bromate, 2-(5-dibromo-2-pyridylazo)-5-(diethylamino)phenol (5-Br-PADAP) and thiocyanate ions. A multivariate optimization was carried out. A linear response was observed between 5.0 and 100 µg L(-1) BrO3(-) and the detection limit was estimated as 2.0 µg L(-1) (99.7% confidence level). The coefficient of variation (n=20) and sampling rate were estimated as 1.0% and 40 determinations per hour, respectively. Reagent consumption was estimated as 0.17 µg of 5-Br-PADAP and 230 μg of NaSCN per measurement, generating 6.0 mL of waste. Bromide determination was carried out after UV-assisted conversion with K2S2O8 using 300 µL of sample within the range 20-400 µg L(-1) Br(-). The generated bromate was then determined by the proposed flow system. The results for tap and commercial mineral water samples agreed with those obtained with the reference procedure at the 95% confidence level. The proposed procedure is therefore a sensitive, environmentally friendly and reliable alternative for inorganic bromine speciation.
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Affiliation(s)
- Diogo L Rocha
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, PO Box 96, 13400-970, Piracicaba, SP, Brazil
| | - Marcos C Machado
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, PO Box 96, 13400-970, Piracicaba, SP, Brazil
| | - Wanessa R Melchert
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, PO Box 9, 13418-970, Piracicaba, SP, Brazil.
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Leepipatpaiboon N, Pancharoen U, Sunsandee N, Ramakul P. Factorial design in optimization of the separation of uranium from yellowcake across a hollow fiber supported liquid membrane, with mass transport modeling. KOREAN J CHEM ENG 2014. [DOI: 10.1007/s11814-013-0294-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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10
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Saraji M, Khaje N, Ghani M. Cetyltrimethylammonium-coated magnetic nanoparticles for the extraction of bromate, followed by its spectrophotometric determination. Mikrochim Acta 2014. [DOI: 10.1007/s00604-014-1188-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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11
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Al-Saidi HM. Highly sensitive procedure for the determination of ultra-trace amounts of bromate ions in water by dispersive liquid-liquid microextraction combined with UV-Vis spectrophotometry. ACTA ACUST UNITED AC 2012. [DOI: 10.5155/eurjchem.3.2.202-207.590] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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12
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CdSe quantum dots capped PAMAM dendrimer nanocomposites for sensing nitroaromatic compounds. Talanta 2011; 83:1335-40. [DOI: 10.1016/j.talanta.2010.10.056] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Revised: 10/20/2010] [Accepted: 10/29/2010] [Indexed: 11/19/2022]
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13
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Oliveira SM, Segundo MA, Rangel AOSS, Lima JLFC, Cerdà V. Spectrophotometric Determination of Bromate in Water Using Multisyringe Flow Injection Analysis. ANAL LETT 2011. [DOI: 10.1080/00032719.2010.500771] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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14
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Duarte AJ, Rocha C, Silveira F, Aguilar GG, Jorge PAS, Leitão JMM, Algarra M, Esteves da Silva JCG. Luminol-Doped Nanostructured Composite Materials for Chemiluminescent Sensing of Hydrogen Peroxide. ANAL LETT 2010. [DOI: 10.1080/00032711003731456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Platikanov S, Tauler R, Rodrigues PMSM, Antunes MCG, Pereira D, Esteves da Silva JCG. Factorial analysis of the trihalomethane formation in the reaction of colloidal, hydrophobic, and transphilic fractions of DOM with free chlorine. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2010; 17:1389-1400. [PMID: 20419477 DOI: 10.1007/s11356-010-0320-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 02/24/2010] [Indexed: 05/29/2023]
Abstract
BACKGROUND, AIM, AND SCOPE This study focuses on the factors that affect trihalomethane (THMs) formation when dissolved organic matter (DOM) fractions (colloidal, hydrophobic, and transphilic fractions) in aqueous solutions were disinfected with chlorine. MATERIALS AND METHODS DOM fractions were isolated and fractionated from filtered lake water and were characterized by elemental analysis. The investigation involved a screening Placket-Burman factorial analysis design of five factors (DOM concentration, chlorine dose, temperature, pH, and bromide concentration) and a Box-Behnken design for a detailed assessment of the three most important factor effects (DOM concentration, chlorine dose, and temperature). RESULTS The results showed that colloidal fraction has a relatively low contribution to THM formation; transphilic fraction was responsible for about 50% of the chloroform generation, and the hydrophobic fraction was the most important to the brominated THM formation. DISCUSSION When colloidal and hydrophobic fraction solutions were disinfected, the most significant factors were the following: higher DOM fraction concentration led to higher THM concentration, an increase of pH corresponded to higher concentration levels of chloroform and reduced bromoform, higher levels of chlorine dose and temperature produced a rise in the total THM formation, especially of the chlorinated THMs; higher bromide concentration generates higher concentrations of brominated THMs. Moreover, linear models were implemented and response surface plots were obtained for the four THM concentrations and their total sum in the disinfection solution as a function of the DOM concentration, chlorine dose, and temperature. Overall, results indicated that THM formation models were very complex due to individual factor effects and significant interactions among the factors. CONCLUSIONS In order to reduce the concentration of THMs in drinking water, DOM concentrations must be reduced in the water prior to the disinfection. Fractionation of DOM, together with an elemental analysis of the fractions, is important issue in the revealing of the quality and quantity characteristics of DOM. Systematic study composed from DOM fraction investigation and factorial analysis of the responsible parameters in the THM formation reaction can, after an evaluation of the adjustment of the models with the reality, serves well for the evaluation of the spatial and temporal variability in the THM formation in dependence of DOM. However, taking into consideration the natural complexity of DOM, different operations and a strict control of them (like coagulation/flocculation and filtration) has to be used to quantitatively remove DOM from the raw water. RECOMMENDATIONS AND PERSPECTIVES Assuming that this study represents a local case study, similar experiments can be easily applied and will supply with relevant information every local water treatment plant meeting problems with THM formation. The coagulation/flocculation and the filtration stages are the main mechanisms to remove DOM, particularly the colloidal DOM fraction. With the objective to minimize THMs generation, different unit operation designed to quantitatively remove DOM from water must be optimized.
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Affiliation(s)
- Stefan Platikanov
- Department of Environmental Chemistry, IIQAB-CSIC, Jordi Girona 18-26, 08026, Barcelona, Spain
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Almendral MJ, Alonso A, Fuentes MS. Development of new methodologies for on-line determination of the bromate ion in samples of water subjected to ozonation treatment. ACTA ACUST UNITED AC 2009; 11:1381-8. [DOI: 10.1039/b900773c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Almendral-Parra MJ, Alonso-Mateos A, Fuentes-Prieto MS. Online Monitoring of Bromate in Ozonized Water Without a Previous Separation Process. J Fluoresc 2008; 18:1169-79. [DOI: 10.1007/s10895-008-0369-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2008] [Accepted: 03/14/2008] [Indexed: 10/21/2022]
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Marques SM, da Silva JCGE. An optimized luciferase bioluminescent assay for coenzyme A. Anal Bioanal Chem 2008; 391:2161-8. [PMID: 18437362 DOI: 10.1007/s00216-008-2117-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Revised: 03/31/2008] [Accepted: 04/02/2008] [Indexed: 11/30/2022]
Abstract
A new bioluminescent method for coenzyme A (CoA) quantification is described. It is based on the enzymatic conversion of dehydroluciferyl-adenylate (L-AMP) into dehydroluciferyl-coenzyme A (L-CoA) by firefly luciferase (E.C. 1.13.12.7) (LUC), which causes a flash of light that can be measured in a luminometer. The method was subjected to optimization using experimental design methodologies to obtain optimum values for the concentrations of L-AMP ([L-AMP]), luciferase ([LUC]), ATP ([ATP]) and luciferin ([LH(2)]). This method has a linear response over the range of 0.25-4 microM of CoA, with a limit of detection (LOD) of 0.24 microM and a limit of quantification (LOQ) of 0.80 microM. The assay has a relative standard deviation of about 7%. By coupling this optimized procedure to bioluminescent detection, a sensible and robust method can be obtained for the analysis of CoA.
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Affiliation(s)
- Simone M Marques
- Centro de Investigação em Química (CIQ-UP), Chemistry Department, Faculty of Sciences, University of Porto, R. Campo Alegre 687, 4169-007, Porto, Portugal
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Leitão JM, Esteves da Silva JC. Factorial analysis optimization of a Diltiazem kinetic spectrophotometric quantification method. Anal Chim Acta 2008; 609:1-12. [DOI: 10.1016/j.aca.2007.12.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2007] [Revised: 12/14/2007] [Accepted: 12/18/2007] [Indexed: 11/24/2022]
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Francis PS, Hogan CF. Luminescence. ADVANCES IN FLOW INJECTION ANALYSIS AND RELATED TECHNIQUES 2008. [DOI: 10.1016/s0166-526x(08)00613-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Rodrigues PMSM, Esteves da Silva JCG, Antunes MCG. Factorial analysis of the trihalomethanes formation in water disinfection using chlorine. Anal Chim Acta 2007; 595:266-74. [PMID: 17606009 DOI: 10.1016/j.aca.2006.12.031] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2006] [Revised: 12/12/2006] [Accepted: 12/14/2006] [Indexed: 11/18/2022]
Abstract
The factors that affect trihalomethane (THM) (chloroform, bromodichloromethane, chlorodibromomethane and bromoform) formation from the chlorination of aqueous solutions of hydrophobic fulvic acids (FA) were investigated in a prototype laboratorial simulation using factorial analysis. This strategy involved a fractional factorial design (16 plus 5 center experiments) of five factors (fulvic acids concentration, chlorine dose, temperature, pH and bromide concentration) and a Box Behnken design (12 plus 3 center experiments) for the detailed analysis of three factors (FA concentration, chlorine dose and temperature). The concentration of THM was determined by headspace analysis by GC-ECD. The most significant factors that affect the four THM productions were the following: chloroform-FA concentration and temperature; bromodichloromethane-FA concentration and chlorine dose; chlorodibromomethane-chlorine dose; and, bromoform-chlorine dose and bromide concentration. Moreover, linear models were obtained for the four THM concentrations in the disinfection solution as function of the FA concentration, chlorine dose and temperature, and it was observed that the complexity of the models (number of significant factors and interactions) increased with increasing bromine atoms in the THM. Also, this study shows that reducing the FA concentration the relative amount of bromated THM increases.
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Affiliation(s)
- Pedro M S M Rodrigues
- Departamento de Engenharia Civil, Instituto Politécnico da Guarda, Av. Francisco Sá Carneiro 50, 6300-559 Guarda, Portugal
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Uraisin K, Takayanagi T, Nacapricha D, Motomizu S. Novel oxidation reaction of prochlorperazine with bromate in the presence of synergistic activators and its application to trace determination by flow injection/spectrophotometric method. Anal Chim Acta 2006; 580:68-74. [PMID: 17723757 DOI: 10.1016/j.aca.2006.07.045] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2006] [Revised: 07/18/2006] [Accepted: 07/20/2006] [Indexed: 11/26/2022]
Abstract
A simple and fast flow injection spectrophotometric method for the determination of bromate in water samples was developed. The detection system is based on the oxidation of prochlorperazine (PCP) with bromate in strongly acidic medium. Large amounts of chloride and bromide was found, for the first time, to act as an activator, and to enhance the sensitivity for bromate detection. The oxidation product of PCP gives pink color, which can be used to monitor the reaction spectrophotometrically at 525 nm. Under the optimal conditions, the method is selective; only nitrite, chlorite and hypochlorite can interfere with the determination of bromate. The elimination of these three ions is discussed. The calibration graph for bromate determination was linear in the range of 10-130 microg L(-1) with a detection limit of 2.3 microg L(-1). The repeatability was satisfactory, with the relative standard deviation of 1.1% (25 microg L(-1), n=10). The sample throughput was 44 h(-1). The proposed method was found to be highly reliable for screening drinking waters containing bromate, which is above or below legislation limit of 10 microg L(-1).
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Affiliation(s)
- Kanchana Uraisin
- Department of Chemistry, Faculty of Science, Okayama University, 3-1-1 Tsushimanaka, Okayama 700-8530, Japan
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Ordeig O, Banks C, Del Campo F, Muñoz F, Compton R. Electroanalysis of Bromate, Iodate and Chlorate at Tungsten Oxide Modified Platinum Microelectrode Arrays. ELECTROANAL 2006. [DOI: 10.1002/elan.200603570] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Chen XL, Zhao LX, Lin JM. Chemiluminescence of ClO3−-SO32−-Rh6G-SDBS System and Its Application to the Determination of Sulfite. CHINESE J CHEM 2006. [DOI: 10.1002/cjoc.200690023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Soto-Chinchilla JJ, Gámiz-Gracia L, García-Campaña AM, Cuadros-Rodríguez L. A new strategy for the chemiluminescent screening analysis of total N-methylcarbamate content in water. Anal Chim Acta 2005. [DOI: 10.1016/j.aca.2004.11.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Fay N, Dempsey E, McCormac T. Assembly, electrochemical characterisation and electrocatalytic ability of multilayer films based on [Fe(bpy)3]2+, and the Dawson heteropolyanion, [P2W18O62]6−. J Electroanal Chem (Lausanne) 2005. [DOI: 10.1016/j.jelechem.2004.07.038] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Li B, Liu M, Zhang Z, Xu C. Flow-Injection Chemiluminescence Determination of Formaldehyde with a Bromate-Rhodamine 6G System. ANAL SCI 2003; 19:1643-6. [PMID: 14696929 DOI: 10.2116/analsci.19.1643] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In this paper, a novel flow-injection chemiluminescence (CL) system for the determination of formaldehyde is described. It is based on a strong enhance effect of formaldehyde on the weak CL emission of the reaction between potassium bromate and rhodamine 6G in a sulfuric acid medium. A possible mechanism for this CL reaction is proposed. A CL calibration graph was linear in the range of 0.8 - 200 microg l(-1) and the detection limit was 0.3 microg l(-1) (3sigma). The relative standard deviation was less than 3% for 10 microg l(-1) formaldehyde (n = 11). The method has been applied to determine formaldehyde in the air samples.
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Affiliation(s)
- Baoxin Li
- Department of Chemistry, School of Chemistry and Materials Science, Shaanxi Normal University, Xi'an, 710062, PR China
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