scholarly journals Carboxyl-Functionalized, Europium Nanoparticle-Based Fluorescent Immunochromatographic Assay for Sensitive Detection of Citrinin in Monascus Fermented Food

Toxins ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 605 ◽  
Author(s):  
Erjing Chen ◽  
Ying Xu ◽  
Biao Ma ◽  
Haifeng Cui ◽  
Chuanxin Sun ◽  
...  
Keyword(s):  
Detection Limit ◽  
High Performance ◽  
Visual Detection ◽  
Test Strip ◽  
Fermented Food ◽  
Fermented Foods ◽  
Optimum Conditions ◽  
Matrix Interference ◽  
Relative Standard ◽  
Europium Nanoparticles

A fluorescent immunochromatographic test strip (FICTS) based on the use of europium nanoparticles (EuNPs) was developed and applied to detect citrinin (CIT) in Monascus fermented food. The sensitivity of the immunoassay to detect CIT was greatly improved by the use of a specific monoclonal antibody to attach EuNPs to form a probe. Under optimum conditions, the visual detection limit was 2.5 ng/mL, and the detection limit of the instrument was 0.05 ng/mL. According to the results, the IC50 was 0.4 ng/mL. Matrix interference from various Monascus fermented foods was investigated in food sample detection. The immunosensor also demonstrated high recoveries (86.8–113.0%) and low relative standard deviations (RSDs) (1.8–15.3%) when testing spiked Monascus fermented food. The detection results of this method showed a good correlation (R2 > 0.98) with high-performance liquid chromatography (HPLC). The results showed that the FICTS method could be used as a rapid, sensitive method to detect CIT in Monascus fermented food.

scholarly journals Simultaneous Rapid Detection of Aflatoxin B1 and Ochratoxin A in Spices Using Lateral Flow Immuno-Chromatographic Assay

Foods ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2738
Author(s):  
Xue Zhao ◽  
Xindi Jin ◽  
Zhang Lin ◽  
Qi Guo ◽  
Bin Liu ◽  
...  
Keyword(s):  
Ochratoxin A ◽  
Aflatoxin B1 ◽  
High Performance ◽  
Simultaneous Detection ◽  
High Sensitivity ◽  
Strong Stability ◽  
Test Strip ◽  
Chromatography Analysis ◽  
Relative Standard ◽  
Strip Test

Spices are susceptible to contamination by aflatoxin B1 (AFB1) and ochratoxin A (OTA), which are both mycotoxins with high toxicity and carcinogenicity. In this study, we aimed to develop an immuno-chromatographic strip test for the simultaneous quantification of AFB1 and OTA in spices by spraying the coupled antigens AFB1–ovalbumin (AFB1–OVA) and OTA–ovalbumin (OTA–OVA) on a nitrocellulose membrane. The test strip had high sensitivity, good specificity, and strong stability. The detection limits of these two mycotoxins in Chinese prickly ash, pepper, chili, cinnamon, and aniseed were 5 μg/kg. The false positivity rate was 2%, and the false negativity rate was 0%. The maximum coefficient of variation was 4.28% between batches and 5.72% within batches. The average recovery rates of AFB1 and OTA in spices were 81.2–113.7% and 82.2–118.6%, respectively, and the relative standard deviation (RSD) was <10%. The actual sample detection was consistent with high performance liquid chromatography analysis results. Therefore, the immuno-chromatographic test strips developed in this study can be used for the on-site simultaneous detection of AFB1 and OTA in spices. This method would allow the relevant regulatory agencies to strengthen supervision in an effort to reduce the possible human health hazards of such contaminated spices.

A Study on Gadolinium Sensitized Chemiluminescence System

2012 ◽  
Vol 535-537 ◽  
pp. 1337-1340 ◽  
Author(s):  
Chi Yang ◽  
Nai Lin Ren
Keyword(s):  
Standard Deviation ◽  
Detection Limit ◽  
Linear Relationship ◽  
Relative Standard Deviation ◽  
Optimum Conditions ◽  
Chemiluminescence Intensity ◽  
Experimental Conditions ◽  
Relative Standard

A new chemiluminescence system was built by using gadolinium as sensitizer, and the analysis capabilities of this system was tested as below. The method is based on chemluminescence of Ce (IV)-SO32- sensitized by Gd3+-OFLX. The effects of some critical experimental conditions were discussed and the optimum conditions for chemluminescence emission were investigated. The linear relationship between the relative chemiluminescence intensity and the concentration of OFLX is in the range of 2×10-9 g/mL～5×10-7 g/mL with a detection limit of 1.0×10-9g/mL .The relative standard deviation is 2.8% (n=11) for a level of 5.0×10-7 g/mL. The method has been applied to the analysis of OFLX in tablets with satisfactory results.

Cloud Point Extraction-Fluorimetric Combined Methodology for the Determination of Magnolol

2013 ◽  
Vol 699 ◽  
pp. 34-39
Author(s):  
Li Liu ◽  
Xia Shi Zhu
Keyword(s):  
Standard Deviation ◽  
Detection Limit ◽  
Cloud Point ◽  
Relative Standard Deviation ◽  
Cloud Point Extraction ◽  
Calibration Graph ◽  
Optimum Conditions ◽  
Relative Standard ◽  
Triton X

A new Triton X-114 cloud point extraction combined with fluorometry method for analysis of magnolol in drug samples was developed. Under the optimum conditions, the calibration graph was linear in the range of 2.0-150.0ng/mL of magnolol in the initial solution with r = 0.9998. Detection limit (DL) was 0.03ng/mL (S/N=3) and the relative standard deviation (RSD) for 20.0ng/mL of magnolol was 2.79%(n=11). The method was successfully applied for the determination of magnolol in drug samples with satisfactory results.

Chemiluminescence Enhancement Effect for the Determination of Acetaminophen with the Catalysis of Manganese Deuteroporphyrin (Mn(III)DP)

2013 ◽  
Vol 575-576 ◽  
pp. 249-252 ◽  
Author(s):  
Ying Jun Chao ◽  
Liang Xiao Xie ◽  
Wei Cao
Keyword(s):  
Detection Limit ◽  
Pharmaceutical Preparations ◽  
Peak Height ◽  
Enhancement Effect ◽  
Optimum Conditions ◽  
Chemiluminescence Intensity ◽  
Relative Standard ◽  
Alkaline Conditions ◽  
Flow Injection Chemiluminescence

It is found thatManganese Deuteroporphyrin (Mn(Ⅲ)DP) can greatly enhance the chemiluminescence intensity of luminol-hydrogen peroxide system in alkaline conditions. Basing on that fact a flow injection chemiluminescence (CL) method has been developed for the determination of acetaminophen. With the peak height as a quantitative parameter applying optimum conditions, the relative CL intensity was linear with acetaminophen concentration in the range of 1.0×10-9～1.0×10-7 g/mL with a detection limit of 2.8×10-10 g/mL. The relative standard deviation (RSD) was 2.7% for 2.0 x10-8 g/mL acetaminophen (n = 11). The proposed method held low detection limit and was successfully applied to determination of acetaminophen in pharmaceutical preparations.

Spctrophotometric Determination of Trace Ruthenium by its Catalytic Effect on Oxidation of 3,5-DiBr-PADAP with KIO4

2012 ◽  
Vol 554-556 ◽  
pp. 1999-2005
Author(s):  
Zhi Rong Zhou ◽  
Qun Wang ◽  
Shu Yuan Zhang
Keyword(s):  
Activation Energy ◽  
Standard Deviation ◽  
Detection Limit ◽  
Catalytic Reaction ◽  
Oxidation Reaction ◽  
Catalytic Effect ◽  
Optimum Conditions ◽  
Potassium Periodate ◽  
Relative Standard

A spectrophotometric method for the determination of ruthenium (III) is described, based on its catalytic effect on the oxidation reaction of 2-[(3,5-dibromo-2-pyridy)azo]-5-diethylaminophenol (3,5-diBr-PADAP) with potassium periodate in 0.008 mol/L sodium hydroxide medium and in the presence of OP emulsifier (p-iso-octyl phenoxy polyethoxy ethanol) at 100 °C. The above reaction is followed spectrophotometrically by measuring the decrease in the absorbance at 530 nm for the catalytic reaction of 3,5-diBr-PADAP. The calibration curve for the recommended method was linear in the concentration range over 0.04 µg/L–1.0 µg/L and the detection limit of the method for Ru (III) is 0.012 µg/L. The influence of the factors such as acidity, concentration of reactants, reaction time, temperature and co-existing ions on the reaction is discussed. The optimum conditions of reaction are established and some kinetic parameters are determined. The apparent activation energy of catalytic reaction is 100.48 kJ/mol. The relative standard deviation for the determination of ruthenium (III) at the concentration of 0.02 µg/25mL is calculated to be 2.30 % (n=11). In combination with distilled separation, the method has been successfully applied for the determination of trace ruthenium (III) in some ores and metallurgy products with the relative standard deviations (RSD) over 1.8 %–2.9 % and the recovery over 98.1 %–103.1 %.

scholarly journals Determination of Aflatoxins in Medicinal Plants by High-Performance Liquid Chromatography–Tandem Mass Spectrometry

2013 ◽  
Vol 16 (2) ◽  
pp. 321 ◽  
Author(s):  
Nadeem Ahmad Siddique ◽  
Mohd Mujeeb ◽  
Sayeed Ahmad ◽  
Bibhu P. Panda ◽  
Mohd Makhmoor
Keyword(s):  
Mass Spectrometry ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Detection Limit ◽  
Medicinal Plants ◽  
High Performance ◽  
Mucuna Pruriens ◽  
Relative Standard ◽  
Liquid Chromatography Tandem Mass ◽  
Quality Of Products

Purpose. The intention of the proposed work is to study the presence of the aflatoxins B1, B2, G1 and G2 in medicinal plants, namely Mucuna pruriens, Delphinium denudatum and Portulaca oleraceae. Methodology. The aflatoxins were extracted, purified by immunoaffinity column chromatography and analysed by high-performance liquid chromatography–tandem quadrupole mass spectrometry with electrospray ionisation (HPLC–MS/MS). Fungal count was carried out in PDA media. Results. A good linear relationship was found for AFB1, AFB2, AFG1 and AFG2 at 1–10 ppb (r>0.9995). The analyte accuracy under three different spiking levels was 86.7–108.1 %, with low per cent relative standard deviations in each case. The aflatoxins can be separated within 5 to7 min using an Agilent XDB C18-column. We found that AFB1 and AFB2 were in trace amounts below the detection limit in M. pruriens whilst they were not detected in D. denudatum. P. oleraceae was found to be contaminated with AFB1 and AFB2. AFG1 and AFG2 were not detected in M. pruriens, P. oleraceae and were below the detection limit in D. denudatum. This was consistent with very low numbers of fungal colonies observed after 6 hr of incubation. Conclusion. The analytical method developed is simple, precise, accurate, economical and can be effectively used to determine the aflatoxins in medicinal plants and therefore to control the quality of products. The aflatoxin levels in the plant extracts examined were related to the minimal fungal load in the medicinal plants examined. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

scholarly journals Analysis of ochratoxin A in malt beverage samples using dispersive liquid–liquid microextraction coupled with liquid chromatography-fluorescence detection

2013 ◽  
Vol 31 (No. 5) ◽  
pp. 520-525 ◽  
Author(s):  
M. Maham ◽  
V. Kiarostami ◽  
S. Waqif-Husain ◽  
R. Karami-Osboo ◽  
M. Mirabolfathy
Keyword(s):  
Liquid Chromatography ◽  
Ochratoxin A ◽  
Fluorescence Detection ◽  
High Performance ◽  
Optimum Conditions ◽  
Beverage Samples ◽  
Extraction Solvent ◽  
Relative Standard ◽  
The Mean ◽  
Liquid Microextraction

A simple and economic procedure based on dispersive liquid&ndash;liquid microextraction has been applied to extract and pre-concentrate trace levels of ochratoxin A (OTA) in malt beverage prior to analysis using high performance liquid chromatography with fluorescence detection. The method was based on the formation of fine droplets of a water-immiscible extraction solvent in the sample solution using a water-miscible disperser solvent. The influences of various parameters such as the type and volume of extraction and disperser solvents, centrifuging time, sonication time, and salt concentration on the extraction efficiency of ochratoxin A were investigated. Under optimum conditions, the relative standard deviations for five replicates of 2 ng/ml of OTA were 3.4% as within-day and 6.2% as between-day precisions. The detection limit (S/N = 3) was 0.1 ng/ml and the mean recoveries of OTA from malt beverage samples at spiking levels of 0.5, 2, and 4 ng/ml were in the range of 104&ndash;108.2%.

scholarly journals Quantitative Determination of Arbutin and Hydroquinone in Different Plant Materials by HPLC

2012 ◽  
Vol 40 (2) ◽  
pp. 109 ◽  
Author(s):  
Izabela RYCHLINSKA ◽  
Slawomira NOWAK
Keyword(s):  
High Performance ◽  
Raw Materials ◽  
Hplc Method ◽  
Fast Method ◽  
Optimum Conditions ◽  
Plant Materials ◽  
Ledum Palustre ◽  
Relative Standard ◽  
First Time

A simple, fast method of high-performance liquid chromatography for the determination and quantification of arbutin and hydroquinone in many different raw materials was developed and validated. The optimum conditions for the separation and detection of these two constituents were achieved on a LiChro-CARD 125-4 Superspher®100 RP-18 column with the water-methanol (gradient elution) mobile phase and recorded at 289 nm. The purities of peaks were verified by PDA analysis of impurities. The results of validation have shown that the HPLC method is stable and accurate for the simultaneous determination of arbutin and hydroquinone in extracts from various plants. The developed method gave a good sensitivity (LOD 1µg/ml for arbutin and 0.49 µg/ml for hydroquinone) with linearity R2 >0.9993 (for both). The relative standard deviation of the method was less than 2.53% for intra-day assays and 3.23% for inter-day assay, the accuracy of the recovery test ranged from 98.96% to 106.4%. This method was used in comparative qualitative analysis of arbutin and hydroquinone in 16 different raw materials from families Lamiaceae, Ericacaeae, Saxifragaceae, Rosaceae. The content of arbutin in B. ciliata, B. cordifolia and Ledum palustre was examined for the first time.

scholarly journals Development and validation of kinetic spectrophotometric method for herbicide bromfenoxim determination

2016 ◽  
Vol 14 (2) ◽  
pp. 115-123
Author(s):  
Emilija Pecev-Marinkovic ◽  
Zora Grahovac ◽  
Snezana Mitic ◽  
Aleksandra Pavlovic ◽  
Ivana Rasic-Misic ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Detection Limit ◽  
Spectrophotometric Method ◽  
Inhibitory Effect ◽  
Sulfanilic Acid ◽  
Hplc Method ◽  
Optimum Conditions ◽  
Relative Standard ◽  
Kinetic Spectrophotometric ◽  
Development And Validation

A kinetic spectrophotometric method for determining the residues of herbicide bromofenoxim (BrFX) has been developed and validated. The proposed method is based on the inhibitory effect of BrFX on the oxidation of sulfanilic acid (SA) by hydrogen peroxide in the presence of Cu(II) ion, which was monitored at 370 nm. The variables affecting the rate of the reaction were investigated and the optimum conditions were established. BrFX can be measured in the range of 0.041 - 0.46 ?g/ml and 0.46 - 13.86 ?g/ml. The detection limit of the method with 3? criteria is 0.0077 ?g/ml. The relative standard deviations for five replicate determinations of 0.041, 0.24 and 0.46 ?g/ml BrFX are 3.0, 5.32 and 2.85%, respectively. This method can be successfully used to determine BrFX concentration in baby juice samples. The HPLC method is used to verify the results. The results obtained for the same samples by the two methods are quite comparable.

scholarly journals Detection of Urethane in Non-alcoholic Fermented Food

2020 ◽  
Vol 189 ◽  
pp. 02003
Author(s):  
Zhang Lihua
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Work Experience ◽  
High Performance ◽  
Isotope Labeling ◽  
Fermented Food ◽  
Detection Methods ◽  
Gas Chromatography Mass Spectrometry ◽  
Fermented Foods ◽  
Resonance Detection

Among fermented foods, urethane often appears, which is a “2A” grade carcinogen. There are many types of fermented foods in my country, and the detection methods are not uniform enough, and no specific urethane detection standards have been formed. This article summarizes the specific experiments and results analysis based on previous work experience. At the same time, this article discusses six aspects from thin layer analysis, gas chromatography, gas chromatography-mass spectrometry, two-dimensional live multidimensional gas chromatography with stable isotope labeling mass spectrometry, high performance liquid chromatography-fluorescence, and nuclear magnetic resonance detection. The detection method of urethane in non-alcoholic fermented foods is introduced.

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