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Mulyasuryani A, Prananto YP, Fardiyah Q, Widwiastuti H, Darjito D. Application of Chitosan-Based Molecularly Imprinted Polymer in Development of Electrochemical Sensor for p-Aminophenol Determination. Polymers (Basel) 2023; 15:polym15081818. [PMID: 37111963 PMCID: PMC10144842 DOI: 10.3390/polym15081818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/26/2023] [Accepted: 04/04/2023] [Indexed: 04/29/2023] Open
Abstract
Molecularly Imprinted Polymers (MIPs) have specific recognition capabilities and have been widely used for electrochemical sensors with high selectivity. In this study, an electrochemical sensor was developed for the determination of p-aminophenol (p-AP) by modifying the screen-printed carbon electrode (SPCE) with chitosan-based MIP. The MIP was made from p-AP as a template, chitosan (CH) as a base polymer, and glutaraldehyde and sodium tripolyphosphate as the crosslinkers. MIP characterization was conducted based on membrane surface morphology, FT-IR spectrum, and electrochemical properties of the modified SPCE. The results showed that the MIP was able to selectively accumulate analytes on the electrode surface, in which MIP with glutaraldehyde as a crosslinker was able to increase the signal. Under optimum conditions, the anodic peak current from the sensor increased linearly in the range of 0.5-35 µM p-AP concentration, with sensitivity of (3.6 ± 0.1) µA/µM, detection limit (S/N = 3) of (2.1 ± 0.1) µM, and quantification limit of (7.5 ± 0.1) µM. In addition, the developed sensor exhibited high selectivity with an accuracy of (94.11 ± 0.01)%.
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Affiliation(s)
- Ani Mulyasuryani
- Chemistry Department, Faculty of Mathematics and Natural Sciences, Universitas Brawijaya, Jl. Veteran, Malang 65145, Indonesia
| | - Yuniar Ponco Prananto
- Chemistry Department, Faculty of Mathematics and Natural Sciences, Universitas Brawijaya, Jl. Veteran, Malang 65145, Indonesia
| | - Qonitah Fardiyah
- Chemistry Department, Faculty of Mathematics and Natural Sciences, Universitas Brawijaya, Jl. Veteran, Malang 65145, Indonesia
| | - Hanandayu Widwiastuti
- Pharmaceutical and Food Analysis Department, Health Polytechnic, Jl. Besar Ijen 77C, Malang 65112, Indonesia
| | - Darjito Darjito
- Chemistry Department, Faculty of Mathematics and Natural Sciences, Universitas Brawijaya, Jl. Veteran, Malang 65145, Indonesia
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Da’na E, Taha A, El-Aassar MR. Catalytic Reduction of p-Nitrophenol on MnO 2/Zeolite -13X Prepared with Lawsonia inermis Extract as a Stabilizing and Capping Agent. Nanomaterials (Basel) 2023; 13:785. [PMID: 36839153 PMCID: PMC9960385 DOI: 10.3390/nano13040785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/12/2023] [Accepted: 02/18/2023] [Indexed: 06/18/2023]
Abstract
p-nitrophenol (pNP) is a highly toxic organic compound and is considered carcinogenic and mutagenic. It is a very stable compound with high resistance to chemical or biological degradation. As a result, the elimination of this pollutant has been very challenging for many researchers. Catalytic reduction is one of the most promising techniques, if a suitable catalyst is developed. Thus, this work aims to prepare an eco-friendly catalyst via a simple and low-cost route and apply it for the conversion of the toxic p-nitrophenol (pNP) into a non-toxic p-aminophenol (pAP) that is widely used in industry. Manganese oxide was prepared in an environmentally friendly manner with the aid of Lawsonia inermis (henna) extract as a stabilizing and capping agent and loaded on the surface of 13X molecular sieve zeolite. The UV-Vis spectrum, EDS, and XRD patterns confirmed the formation of the pure MnO2 loaded on the zeolite crystalline network. The TGA analysis showed that the samples prepared by loading MnO2 on zeolite (Mn2Z, Mn3Z, and Mn4Z) lost more mass than pure MnO2 (Mn) or zeolite (Z), which is mainly moisture adsorbed on the surface. This indicates a better dispersion of MnO2 on the surface of zeolite compared to pure MnO2, and thus a higher number of active adsorption sites. SEM images and EDS confirmed the dispersion of the MnO2 on the surface of the zeolite. Results showed a very fast reduction rate, following the order Mn2Z > Mn3Z > Mn4Z > Mn > Z. With sample Mn2Z, 96% reduction of pNP was achieved in 9 min and 100% in 30 min. For Mn3Z, Mn4Z, and Mn, 98% reduction was achieved in 20 min and 100% in 30 min. Zeolite was the slowest, with only a 40% reduction in 30 min. Increasing the amount of zeolite in the synthesis mixture resulted in lower reduction efficiency. The kinetic study indicated that the reduction of p-nitrophenol on the surface of the prepared nanocomposite follows the pseudo-first-order model. The results show that the proposed nanocomposite is very effective and very promising to be commercially applied in water treatment, due to its low cost, simple synthesis procedure, and reusability.
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Affiliation(s)
- Enshirah Da’na
- Department of Biomedical Engineering, King Faisal University, P.O. Box 400, Alahsa 31982, Saudi Arabia
| | - Amel Taha
- Department of Chemistry, King Faisal University, P.O. Box 400, Alahsa 31982, Saudi Arabia
- Department of Chemistry, Faculty of Science and Technology, Al-Neelain University, Khartoum 1112, Sudan
| | - Mohamed R. El-Aassar
- Department of Chemistry, College of Science, Jouf University, Sakaka 2014, Saudi Arabia
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Buckey G, Owens OE, Gabriel AW, Downing CM, Calhoun MC, Cliffel DE. Adsorption and Electropolymerization of p-Aminophenol Reduces Reproducibility of Electrochemical Immunoassays. Molecules 2022; 27:6046. [PMID: 36144780 DOI: 10.3390/molecules27186046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/08/2022] [Accepted: 09/10/2022] [Indexed: 11/21/2022]
Abstract
This paper investigates the electrochemical behavior of p-aminophenol (PAP) on commercially available carbon screen-printed electrodes (CSPEs) and gold screen-printed electrodes (GSPEs) at neutral and basic pHs for the development of inexpensive immunoassays. The electrochemical oxidative signal from PAP results from its adsorption to the electrode. The formation of self-assembled monolayers on gold electrodes prevented PAP adsorption but also reduced its oxidative current, confirming that adsorption increases signal production. On bare electrodes, PAP adsorption results in oxidative current variability depending on the electroactive surface area of the screen-printed electrode. This variability could not be remedied by cleaning and reusing the same GSPE. Decreasing the PAP concentration to 3.8 μM greatly improved the consistency of the measurements, suggesting that the adsorption of PAP is concentration-dependent. Multiple PAP oxidations on the same electrode caused polymerization, limiting PAP in continuous monitoring applications. Infrared and Raman spectroscopy allow the distinction between adsorbed PAP and electropolymerized PAP on the surface of a gold wafer. The results from this study suggest that the use of PAP production in immunoassays with SPEs must be fine-tuned, and electrodes must be cleaned or disposed of between measurements.
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Shaban SM, Moon BS, Pyun DG, Kim DH. A colorimetric alkaline phosphatase biosensor based on p-aminophenol-mediated growth of silver nanoparticles. Colloids Surf B Biointerfaces 2021; 205:111835. [PMID: 33992822 DOI: 10.1016/j.colsurfb.2021.111835] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 04/14/2021] [Accepted: 05/08/2021] [Indexed: 01/13/2023]
Abstract
Alkaline phosphatase (ALP) is an enzyme that catalyzes the dephosphorylation of proteins, nucleic acids, and biomolecules. It is a potential biomarker for diverse diseases such as breast cancer, osteopenia, and hepatobiliary. Herein, we developed a colorimetric sensor for the ALP assay based on its enzymatic activity to dephosphorylate the p-aminophenol phosphate (pAPP) into pAP. In a solution containing silver nanoparticles (AgNPs) and Ag+ ions prepared using a low concentration of NaBH4, pAP mediates the growth of AgNPs by reducing the concentration of Ag+ ions to enhance the intensity of localized surface plasmon resonance as the pAPP cannot induce a reduction of the remaining Ag+ due to the masking of the hydroxyl with phosphate. The quantitative assay of the ALP was demonstrated via the colorimetric detection of the pAP-mediated growth of AgNPs in the presence of an ALP. The highly sensitive enzymatic growth of AgNPs provided a wider dynamic linear range of 0.5-225 U/L with a lower limit of detection of 0.24 U/L than that previously reported. The use of pAP resulted in excellent selectivity of the sensor for the ALP assay in human serum, yielding a high recovery rate and a high precision of 99.2 ± 1.5 % for the standard addition method.
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Affiliation(s)
- Samy M Shaban
- School of Chemical Engineering, Sungkyunkwan University, 16419, Republic of Korea; Biomedical Institute for Convergence at SKKU (BICS), Sungkyunkwan University, 16419, Republic of Korea; Petrochemical Department, Egyptian Petroleum Research Institute, Egypt
| | - Byeong-Seok Moon
- School of Chemical Engineering, Sungkyunkwan University, 16419, Republic of Korea
| | - Do-Gi Pyun
- Biomedical Polymer R&D institute, T&L Co., Ltd, Anseong, 17554, South Korea
| | - Dong-Hwan Kim
- School of Chemical Engineering, Sungkyunkwan University, 16419, Republic of Korea; Biomedical Institute for Convergence at SKKU (BICS), Sungkyunkwan University, 16419, Republic of Korea.
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Smarr MM, Kannan K, Chen Z, Kim S, Buck Louis GM. Male urinary paracetamol and semen quality. Andrology 2017; 5:1082-1088. [PMID: 28853221 PMCID: PMC10506067 DOI: 10.1111/andr.12413] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/28/2017] [Accepted: 07/12/2017] [Indexed: 11/29/2022]
Abstract
The endocrine-disrupting properties of paracetamol have been previously demonstrated in rodent studies of abnormal sperm morphology and diminished testosterone production, in addition to epidemiologic studies of diminished couple fecundity. In this study, we examined the relationship between paracetamol and its metabolite p-aminophenol quantified in a single spot urine and semen quality among 501 male partners of couples planning for pregnancy. Men provided a urine specimen and two fresh semen samples collected approximately one month apart and underwent 24-h analysis for 35 semen quality parameters. Paracetamol and p-aminophenol were quantified in urine by ultra-high-performance liquid chromatography coupled with an electrospray triple quadrupole mass spectrometry. The relationship between natural-log-transformed urinary paracetamol and p-aminophenol rescaled by their standard deviation and 21 Box-Cox-transformed, 14 non-transformed semen parameters was assessed using linear mixed-effects models. The median concentrations (IQR) of urinary paracetamol and p-aminophenol were 15.5 ng/mL (5.44, 73.5) and 978 ng/mL (500, 1596), respectively. Following adjustment for creatinine and age, a 1-standard deviation increase in log-transformed urinary paracetamol was associated with a reduction in beat cross-frequency and an increase in DNA fragmentation [β (95% CI): -0.59 Hz (-1.16, -0.03) and 0.05% (0.01, 0.09), respectively]. These findings were corroborated in models of categorical chemical concentrations; higher concentrations of paracetamol remained associated with reduced beat cross-frequency and increased DNA fragmentation. A 1-standard deviation increase in log-transformed urinary p-aminophenol was associated with a reduction in sperm head area [β (95% CI): -0.1 μm2 (-0.18, -0.02) and width -0.02 μm (-0.04, -0.01)]. However, only the association with sperm head area remained statistically significant in models of p-aminophenol quartiles. Our findings suggest that adult male urinary paracetamol is associated with sperm motility and DNA fragmentation, while the metabolite, p-aminophenol, is predominantly associated with sperm head morphometry.
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Affiliation(s)
- Melissa M. Smarr
- Office of the Director, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20829, USA
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health, and Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Albany, New York 12201, USA
| | - Zhen Chen
- Biostatistic and Bioinformatics Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20829, USA
| | - Sungduk Kim
- Biostatistics Branch Division of Cancer Epidemiology and Genetics National Cancer Institute Bethesda, Maryland, USA
| | - Germaine M. Buck Louis
- Office of the Director, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20829, USA
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Wang C, Zholudov YT, Nsabimana A, Xu G, Li J. Sensitive and selective electrochemical detection of artemisinin based on its reaction with p-aminophenylboronic acid. Anal Chim Acta 2016; 937:39-42. [PMID: 27590543 DOI: 10.1016/j.aca.2016.07.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/16/2016] [Accepted: 07/19/2016] [Indexed: 10/21/2022]
Abstract
The electrochemical detection of artemisinin generally requires high oxidation potential or the use of complex electrode modification. We find that artemisinin can react with p-aminophenylboronic acid to produce easily electrochemically detectable aminophenol for the first time. By making use of the new reaction, we report an alternative method to detect artemisinin through the determination of p-aminophenol. The calibration curve for the determination of artemisinin is linear in the range of 2 μmol L(-1) to 200 μmol L(-1) with the detection limit of 0.8 μmol L(-1), which is more sensitive than other reported electrochemical methods. The relative standard deviation is 4.83% for the determination of 10 μM artemisinin. Because the oxidation potential of p-aminophenol is around 0 V, the present method is high selective. When 40 μM, 90 μM and 140 μM of artemisinin were spiked to compound naphthoquine phosphate tablet samples, the recoveries are 107.6%, 105.4% and 101.7%, respectively. This detection strategy is attractive for the detection of artemisinin and its derivatives. The finding that artemisinin can react with aromatic boronic acid has the potential to be exploited for the development of other sensors, such as fluorescence artemisinin sensors.
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Affiliation(s)
- Chao Wang
- College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, China; State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China
| | - Yuriy T Zholudov
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China; Laboratory of Analytical Optochemotronics, Kharkiv National University of Radio Electronics, 14 Nauka Ave., Kharkiv 61166, Ukraine
| | - Anaclet Nsabimana
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China; University of the Chinese Academy of Sciences, Chinese Academy of Sciences, No. 19A Yuquanlu, Beijing 100049, China
| | - Guobao Xu
- College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, China; State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China.
| | - Jianping Li
- College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, China.
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Smarr MM, Grantz KL, Sundaram R, Maisog JM, Honda M, Kannan K, Buck Louis GM. Urinary paracetamol and time-to-pregnancy. Hum Reprod 2016; 31:2119-27. [PMID: 27412248 DOI: 10.1093/humrep/dew172] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 06/13/2016] [Indexed: 01/01/2023] Open
Abstract
STUDY QUESTION Is preconception urinary paracetamol (acetaminophen) associated with time-to-pregnancy (TTP)? SUMMARY ANSWER Higher urinary paracetamol concentrations among male partners were associated with a longer TTP. WHAT IS KNOWN ALREADY Paracetamol is a commonly used analgesic among women and men of all ages. As metabolites of select chemicals used in the manufacturing of polyurethane foam, dyes and various industrial products, as well as a common medicinal product, paracetamol and its primary metabolite p-aminophenol, are ubiquitous in the environment. Studies investigating the relationship between adult urinary concentrations of paracetamol and TTP are lacking. STUDY DESIGN, SIZE, DURATION This prospective cohort included 501 couples discontinuing contraception for the purposes of attempting conception during the years 2005-2009 and residing in Michigan or Texas, USA. PARTICIPANTS/MATERIALS, SETTING, METHODS Total urinary paracetamol, its metabolite para-aminophenol (p-aminophenol), and a summary measure of both urinary biomarkers were quantified by ultra-performance liquid chromatography coupled with an electrospray triple quadrupole mass spectrometry (UPLC-ESI-MS/MS). Female partners used the Clearblue® digital home test to confirm pregnancy. Cox's proportional odds models for discrete survival time were used to estimate fecundability odds ratios (FORs) and 95% confidence intervals (CIs), adjusting for age, body mass index (BMI), urinary creatinine, preconception smoking status, race/ethnicity and household income. Models were further adjusted for hypothyroidism and hypertension as an attempt to account for possible indications of paracetamol medication use. FOR estimates <1.0 denote a longer TTP (diminished fecundity). Models were performed to examine urinary concentrations of paracetamol as a continuous and variable or categorized into quartiles. In light of TTP being a couple-dependent outcome, models were first performed for females and males, modeled separately, and then modeled for couples with each partner's concentrations being adjusted for the other. MAIN RESULTS AND THE ROLE OF CHANCE Among the 501 enrolled couples, 347 (69%) had an human chorionic gonadotrophin confirmed pregnancy. Urinary concentrations of paracetamol were lowest among females and males who achieved pregnancy and p-aminophenol concentrations were lowest among those not achieving pregnancy. Urinary paracetamol concentrations were higher among female than male partners (Median = 26.6 and 13.2 ng/ml, respectively; P < 0.0001). After adjustment for age, BMI, urinary creatinine, preconception smoking status, race/ethnicity and household income, the highest quartile of male urinary paracetamol was associated with a longer TTP [FOR = 0.67; 95% CI = (0.47, 0.95)]. This association remained after adjustment for chronic health conditions, hypothyroidism and hypertension and female partner's urinary paracetamol concentration [FOR = 0.65; 95% CI = (0.45, 0.94)]. No associations were observed between female or male partners' urinary concentrations of paracetamol or of its metabolite p-aminophenol when urinary concentrations were modeled continuously. LIMITATIONS, REASONS FOR CAUTION Only a single spot urine was available for analysis despite the short-lived nature of paracetamol. Additionally, participants were not asked to provide information on indication of use for paracetamol medications; any underlying conditions for the paracetamol use would have been potential confounders. WIDER IMPLICATIONS OF THE FINDINGS If corroborated with more robust studies, findings from our exploratory analysis may have both clinical and public health relevance among reproductive aged individuals, including those trying for pregnancy, given the prevalent use of paracetamol/acetaminophen medications and the ubiquitous nature of paracetamol in the environment. STUDY FUNDING/COMPETING INTERESTS This research was supported by the National Institutes of Health, Intramural Research Program, and Eunice Kennedy Shriver National Institute of Child Health and Human Development (contracts N01-HD-3-3355; N01-HD-3-3356; NOH-HD-3-3358; HHSN27500001/HHSN27500001). None of the authors have any conflicts to declare.
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Affiliation(s)
- Melissa M Smarr
- Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 6100 Executive Blvd., Room 7B05, Rockville, MD 20852, USA
| | - Katherine L Grantz
- Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Rockville, MD 20852, USA
| | - Rajeshwari Sundaram
- Biostatics and Bioinformatics Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Rockville, MD 20852, USA
| | - José M Maisog
- Glotech, Inc., Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Rockville, MD 20852, USA
| | - Masato Honda
- Wadsworth Center, New York State Department of Health, and Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Albany, NY 12201, USA
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health, and Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Albany, NY 12201, USA
| | - Germaine M Buck Louis
- Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 6100 Executive Blvd., Room 7B05, Rockville, MD 20852, USA
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Rochelet M, Solanas S, Betelli L, Chantemesse B, Vienney F, Hartmann A. Rapid amperometric detection of Escherichia coli in wastewater by measuring β-D glucuronidase activity with disposable carbon sensors. Anal Chim Acta 2015; 892:160-6. [PMID: 26388487 DOI: 10.1016/j.aca.2015.08.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 08/11/2015] [Accepted: 08/19/2015] [Indexed: 11/30/2022]
Abstract
An assay on the indirect amperometric quantification of the β-D-Glucuronidase (GLUase) activity was developed for the rapid and specific detection of Escherichia coli (E. coli) in complex environmental samples. The p-aminophenyl β-D-glucopyranoside (PAPG) was selected as an electrochemical substrate for GLUase measurement and the p-aminophenol (PAP) released during the enzymatic hydrolysis was monitored by cyclic voltammetry with disposable carbon screen-printed sensors. The intensity of the measured anodic peak current was proportional to the amount of GLUase, and therefore to the number of E. coli in the tested sample. Once the substrate concentration and pH values optimized, a GLUase detection limit of 10 ng mL(-1) was achieved. Using a procedure involving a filtration step of the bacteria followed by their incubation with the substrate solution containing both the nonionic detergent Triton X-100 as permeabilization agent and the culture media Luria broth to monitor the growth, filtered bacterial cells ranging from 5 × 10(4) to 10(8) UFC/membrane were detected within 3 h. The amperometric assay was applied to the determination of fecal contamination in raw and treated wastewater samples and it was successfully compared with conventional bacterial plating methods and uidA gene quantitative PCR. Owing to its ability to perform measurements in turbid media, the GLUase amperometric method is a reliable tool for the rapid and decentralized quantification of viable but also nonculturable E. coli in complex environmental samples.
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Affiliation(s)
- Murielle Rochelet
- Université Bourgogne Franche-Comté, UMR1347 Agroécologie, 17 Rue Sully, 21000 Dijon, France.
| | - Sébastien Solanas
- Université Bourgogne Franche-Comté, UMR1347 Agroécologie, 17 Rue Sully, 21000 Dijon, France
| | - Laetitia Betelli
- Université Bourgogne Franche-Comté, UMR1347 Agroécologie, 17 Rue Sully, 21000 Dijon, France
| | - Benoît Chantemesse
- Université Bourgogne Franche-Comté, UMR1347 Agroécologie, 17 Rue Sully, 21000 Dijon, France
| | - Fabienne Vienney
- Université Bourgogne Franche-Comté, UMR1347 Agroécologie, 17 Rue Sully, 21000 Dijon, France
| | - Alain Hartmann
- INRA, UMR1347 Agroécologie, 17 Rue Sully, 21000 Dijon, France
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Javaid R, Kawasaki SI, Suzuki A, Suzuki TM. Simple and rapid hydrogenation of p-nitrophenol with aqueous formic acid in catalytic flow reactors. Beilstein J Org Chem 2013; 9:1156-63. [PMID: 23843908 PMCID: PMC3701373 DOI: 10.3762/bjoc.9.129] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 05/23/2013] [Indexed: 11/23/2022] Open
Abstract
The inner surface of a metallic tube (i.d. 0.5 mm) was coated with a palladium (Pd)-based thin metallic layer by flow electroless plating. Simultaneous plating of Pd and silver (Ag) from their electroless-plating solution produced a mixed distributed bimetallic layer. Preferential acid leaching of Ag from the Pd–Ag layer produced a porous Pd surface. Hydrogenation of p-nitrophenol was examined in the presence of formic acid simply by passing the reaction solution through the catalytic tubular reactors. p-Aminophenol was the sole product of hydrogenation. No side reaction occurred. Reaction conversion with respect to p-nitrophenol was dependent on the catalyst layer type, the temperature, pH, amount of formic acid, and the residence time. A porous and oxidized Pd (PdO) surface gave the best reaction conversion among the catalytic reactors examined. p-Nitrophenol was converted quantitatively to p-aminophenol within 15 s of residence time in the porous PdO reactor at 40 °C. Evolution of carbon dioxide (CO2) was observed during the reaction, although hydrogen (H2) was not found in the gas phase. Dehydrogenation of formic acid did not occur to any practical degree in the absence of p-nitrophenol. Consequently, the nitro group was reduced via hydrogen transfer from formic acid to p-nitrophenol and not by hydrogen generated by dehydrogenation of formic acid.
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Affiliation(s)
- Rahat Javaid
- Research Center for Compact Chemical System, National Institute of Advanced Industrial Science and Technology, AIST, 4-2-1 Nigatake, Miyagino-ku, Sendai, Miyagi 983-8551, Japan
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