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A highly sensitive competitive ELISA was standardized to determine aflatoxin M1 (AFM1) in milk and dairy samples randomly collected from Faisalabad city, using Riedel-de-Haen, Aflatoxin M1 ELISA Systems, (Art–No. 45169). Standards of 5, 10, 25, 50, and 100 ng L?1 AFM1 in sample/standard buffer were used in optimizing anti-AFM1 antibodies and peroxidase–AFM1 conjugate. Linear standard curve showed increase in concentration (log C) accompanied by decrease in maximal absorbance (%B/B0) values (%B/B0 = 124.3 ? 45.0 log C) with highly significant negative correlation (?0.973). The middle of the test (50% B/B0) was at 30 ng L?1 with 6.7 ng L?1 the lowest detection limit (90% B/B0). Duplicate analysis of 41 samples showed AFM1 levels below EC permissible limits (50 ng L?1) with maximums of 40, 13, and 7.4 ng L?1 in milk, yogurt and butter, respectively. However, possibility of exceeding limits cannot be excluded, and demands regular monitoring. 相似文献
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A. Hussain S.H. Tirmazi U. Maqbool M. Asi F.A. Chaughtai 《Journal of environmental science and health. Part. B》2013,48(1):141-151
Abstract The effects of temperatures and solar radiation on the dissipation of 14C‐p,p'‐DDT from a loam soil was studied by quantifying volatilization, mineralization and binding. The major DDT loss occurred by volatilization, which was 1.8 times more at 45oC than at ambient temperature (30°C). Mineralization of DDT slowly increased with time but it decreased slightly with increase in temperature. Binding of DDT to soil was found to be less at higher temperatures (35 and 45°C) as compared to ambient temperature. Degradation of DDT to DDE was faster at higher temperatures. Exposure of non‐sterilized and sterilized soils treated with 14C‐DDT to sunlight in quartz and dark tubes for 6 weeks resulted in significant losses. Volatilization and mineralization in quartz tubes were more as compared to dark tubes. The volatilized organics from the quartz tubes contained larger amounts of p,p'‐DDE than the dark tubes. Further, higher rates of volatilization were found in non‐sterilized soils than in sterilized soils. The results suggest that faster dissipation of DDT from soil under local conditions relates predominantly to increased volatilization as influenced by high temperature and intense solar radiation. 相似文献
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Uzma Maqbool Anwar-Ul-Haq M. Jamil Qureshi 《Journal of environmental science and health. Part. B》2013,48(3):224-230
In-house developed ELISA was standardized to monitor atrazine residues in different environmental samples. The standard curve was linear, indicating an increase in log concentration with decrease in absorbance (%B/B0 = 1.075–0.042 Log C; r = ?0.966). The middle of the test was at 75 ng/L and the lowest detection limit at 4 ng/L. ELISA significantly correlated with the high performance liquid chromatography (HPLC) (r = 0.990). Internal validation showed good accuracy and precision. Maximum atrazine residues were present in Jehlum River water/sediments and maize/sugarcane plant roots. Most of the food samples were found to be contaminated. ELISA required less clean-up steps than HPLC, but showed matrix effect in soil/colored extracts. 相似文献
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Sun-Kwon Kim Hye-Sung Won Shin Wha Lee Jeong Kon Kim Jae-Yoon Shim Pil Ryang Lee Ahm Kim 《黑龙江环境通报》2006,26(2):171-174
Congenital epulis is a benign intraoral tumor that has rarely been diagnosed prenatally. We report a fetus with congenital epulis diagnosed by three-dimensional (3-D) ultrasound and fetal magnetic resonance imaging (MRI) at 35 weeks' gestation. We show an image of congenital epulis using a new ultrasound technique, the 3-D multislice view, which shows images similar to CT or MRI. This is a short case report of congenital epulis diagnosed prenatally by 3-D ultrasound using multislice view and MRI. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Majeed Muhammad Tariq Yu Zhiyuan Maqbool Adnan Genie Mesfin G. Ullah Sana Ahmad Waheed 《Environmental science and pollution research international》2021,28(31):41922-41922
Environmental Science and Pollution Research - A Correction to this paper has been published: https://doi.org/10.1007/s11356-021-13968-6 相似文献
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Muhammad I. Chughtai Uzma Maqbool Mazhar Iqbal Muhammad S. Shah Terence Fodey 《Journal of environmental science and health. Part. B》2017,52(12):871-879
This study was undertaken to develop and validate direct competitive ELISA for the determination of chloramphenicol residues in bovine milk. Antisera and an enzyme-tracer for chloramphenicol were prepared and used to develop an ELISA with inhibition concentrations, IC20 and IC50, of 0.09 and 0.44 ng mL?1, respectively. Milk samples were spiked with standards equivalent to 0, 0.2, 0.3, 0.5, 1.0 &; 1.5 ng mL?1 and extracted in methanol. The mean recoveries were found to be 73–100% with coefficient of variance 7–11%. The decision limit (CCα) and detection capability (CCβ) were calculated as 0.10 and 0.12 ng mL?1, respectively. The results were found comparable with the commercial ELISA, having recoveries of 87 to 100%, CCα 0.09 ng mL?1 and CCβ 0.12 ng mL?1. As per Commission Decision 2002/657/EC, in-house ELISA was further validated by using LC-MS/MS. Mass spectral acquisition was done by using electrospray ionization in the negative ion mode applying single reaction monitoring of the diagnostic transition reaction for CAP (m/z 152, 194 and 257). The calibration curve showed good linearity in concentrations from 0.025 to 1.6 ng mL?1 with correction coefficient 0.9902. The mean recoveries were found to be 88 to 100%. The CCα was calculated as 0.057 ng mL?1 and CCβ 0.10 ng mL?1. Since CCα and CCβ are less than half of the MRPL (0.15 ng mL?1), the test was found suitable for screening and quantification of CAP residues in bovine milk samples. Results of surveillance studies indicated that out of 31 analyzed milk samples, 12.9% samples were found with CAP residues but only 3.2% samples were declared positive with maximum concentration 0.31 ng mL?1, slightly above the MRPL. 相似文献
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Zhao Weijun Hafeez Muhammad Maqbool Adnan Ullah Sana Sohail Sidra 《Environmental science and pollution research international》2021,28(37):51199-51209
Environmental Science and Pollution Research - With rapid economic growth, BRICS is facing enormous burdens of carbon emission and severe issues of income inequality. However, behind this economic... 相似文献
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The objective of this study was to determine the relative influence of reach-specific habitat variables and geographic location on benthic invertebrate assemblages within six ecoregions across the Western USA. This study included 417 sites from six ecoregions. A total of 301 taxa were collected with the highest richness associated with ecoregions dominated by streams with coarse substrate (19-29 taxa per site). Lowest richness (seven to eight taxa per site) was associated with ecoregions dominated by fine-grain substrate. Principle component analysis (PCA) on reach-scale habitat separated the six ecoregions into those in high-gradient mountainous areas (Coast Range, Cascades, and Southern Rockies) and those in lower-gradient ecoregions (Central Great Plains and Central California Valley). Nonmetric multidimensional scaling (NMS) models performed best in ecoregions dominated by coarse-grain substrate and high taxa richness, along with coarse-grain substrates sites combined from multiple ecoregions regardless of location. In contrast, ecoregions or site combinations dominated by fine-grain substrate had poor model performance (high stress). Four NMS models showed that geographic location (i.e. latitude and longitude) was important for: (1) all ecoregions combined, (2) all sites dominated by coarse-grain sub strate combined, (3) Cascades Ecoregion, and (4) Columbia Ecoregion. Local factors (i.e. substrate or water temperature) seem to be overriding factors controlling invertebrate composition across the West, regardless of geographic location. 相似文献