Wash-Free Multiplexed Mix-and-Read Suspension Array Fluorescence Immunoassay for Anthropogenic Markers in Wastewater

Objectives: Staphylococcus aureus is a Gram-positive microorganism. S. aureus can grow in various foods and cause food poisoning by secreting enterotoxins. The most common enterotoxins involved in food poisoning are staphylococcal enterotoxin A and staphylococcal enterotoxin B, but Staphylococcal Enterotoxin A (SEA) is predominant. The main types of food contaminated with SEs are meat and meat products, poultry and eggs, milk and dairy products. The aim of this study was to develop a rapid and sensitive fluorescence immunoassay for detection of staphylococcal enterotoxin A in milk. Methods: Monoclonal and polyclonal antibodies for SEA were produced and characterized. Competitive fluorescence immunoassay based on Magnetic Nanoparticles (MNPs) was performed and optimized. MNPs were used as a solid carrier of the antibodies. The first step of the assay was immunoreaction between the immobilized antibody onto MNPs and SEA in milk sample. Then the fluorescein-SEA conjugate was added to the sample. Thus, competitive immunoreaction between MNP-mAb/MNP-pAb with SEA and SEA-FITC was performed. These immuno-complexes were separated by a magnetic separator and the obtained supernatants were analyzed. The fluorescent signal from the excess of conjugated SEA was proportional to the SEA contained in the milk. The assay duration was only 30 min. Results: The fluorescence immunoassays performed with polyclonal antibody had linear ranges from 5 pg/mL to 100 ng/mL SEA in a buffer, and from 50 pg/mL to 50 ng/mL SEA in spiked milk samples. While the same assays performed with monoclonal antibody had linear ranges from 1 pg/mL to 20 ng/mL SEA in buffer, and from 10 pg/mL to 10 ng/mL SEA in spiked milk samples. The detection limits of the developed immunoassays performed in milk were: 48 pg/mL with polyclonal antibody and 9 pg/mL with monoclonal antibody. Conclusion: A rapid and sensitive fluorescence immunoassay based on magnetic nanoparticles with a polyclonal and monoclonal antibody for determination of staphylococcal enterotoxin A in milk was developed.

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Ball-lens assisted sensitivity improvement of fluorescence immunoassay in microchannels

RSC Advances ◽

10.1039/d1ra04360a ◽

2021 ◽

Vol 11 (44) ◽

pp. 27541-27546

Author(s):

Qingquan Zhang ◽

Jiajia Li ◽

Yuting Su ◽

Xiaoyan Pan ◽

Hongwei Gai

Keyword(s):

Fluorescence Immunoassay ◽

Improvement Method ◽

Sensitivity Improvement

A contactless and ball-lens assisted sensitivity improvement method was present for the fluorescence or luminescence immunoassay in microchannel.

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Development of a multicolor upconversion fluorescence immunoassay for the simultaneous detection of thiamethoxam and dextran by magnetic separation

RSC Advances ◽

10.1039/d0ra07954e ◽

2021 ◽

Vol 11 (1) ◽

pp. 517-524

Author(s):

Chuanyong Li ◽

Wanlin Sun ◽

Lianrun Huang ◽

Nana Sun ◽

Xiude Hua ◽

...

Keyword(s):

Monoclonal Antibodies ◽

Simultaneous Determination ◽

Magnetic Separation ◽

Simultaneous Detection ◽

Fluorescence Immunoassay ◽

Upconversion Fluorescence

The anti-thiamethoxam and anti-dextran monoclonal antibodies were prepared to develop a multicolor upconversion fluorescence immunoassay for the simultaneous determination of thiamethoxam (544 nm) and dextran (477 nm).

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Combination of Suspension Array and Mycelial Growth Assay for Detecting Multiple-Fungicide Resistance in Botrytis cinerea in Hebei Province in China

Plant Disease ◽

10.1094/pdis-07-18-1269-re ◽

2019 ◽

Vol 103 (6) ◽

pp. 1213-1219

Author(s):

Zehua Su ◽

Xin Zhang ◽

Jianjiang Zhao ◽

Wenqiao Wang ◽

Lei Shang ◽

...

Keyword(s):

Botrytis Cinerea ◽

High Throughput ◽

Fungicide Resistance ◽

Mycelial Growth ◽

Accurate Method ◽

Hebei Province ◽

Combination Method ◽

Major Type ◽

Suspension Array ◽

Growth Assay

To provide a high-throughput, efficient, and accurate method to monitor multiple-fungicide resistance of Botrytis cinerea in the field, we used the suspension array, sequencing, and mycelial growth assay in our research. Discriminating-dose bioassays for detecting carbendazim, diethofencarb, boscalid, and iprodione resistance (CarR, DieR, BosR, and IprR, respectively) were used to analyze 257 isolates collected from Hebei Province in China during 2016 and 2017. High resistance frequencies to carbendazim (100%), diethofencarb (92.08%), and iprodione (86.59%) were detected. BosR isolates accounted for 11.67% of the total. In addition, 103 isolates were randomly selected for phenotype and genotype detection. The high-throughput suspension array was utilized to detect eight genotypes simultaneously, including BenA-E198, BenA-198A, SdhB-H272, SdhB-272Y, BcOS1-I365, BcOS1-365S, erg27-F412, and erg27-412S, which were associated with resistance toward carbendazim or diethofencarb, boscalid, iprodione, and fenhexamid (FenR), respectively. Most of the benzimidazole-resistant isolates (81.55%) possessed the E198V mutation in the BenA gene. Ninety-three isolates with dual resistance to carbendazim and diethofencarb showed the E198V/K mutation. All BosR isolates carried the H272R mutation in the SdhB gene. The I365S and Q369P+N373S (66.99%) mutations in the BcOS1 gene were more frequently observed. No mutation was detected in the erg27 gene in Hebei isolates. There were 13 resistance profile phenotypes. Phenotypes with triple resistance were the most common (83.50%), and CarRDieRBosSIprRFenS was the major type. CarR isolates that carried E198V/K/A were all highly resistant (HR) and only one F200Y mutant was moderately resistant (MR) to carbendazim. Isolates that possessed E198V/K were MR or HR to diethofencarb. BosR isolates that possessed H272R mutation were lowly resistant (LR). IprR isolates were all LR or MR. The distribution of half maximal effective concentrations of CarR isolates with E198V/K mutations and IprR isolates with Q369P+N373S mutations significantly increased from 2016 to 2017. Combined with our observations, a combination method of the high-throughput suspension array and the mycelial growth assay was suggested to accurately monitor multiple resistance of B. cinerea in the field.

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Plasmodium vivax: comparison of immunogenicity among proteins expressed in the cell-free systems of Escherichia coli and wheat germ by suspension array assays

Malaria Journal ◽

10.1186/1475-2875-10-192 ◽

2011 ◽

Vol 10 (1) ◽

pp. 192 ◽

Cited By ~ 24

Author(s):

Edmilson Rui ◽

Carmen Fernandez-Becerra ◽

Satoru Takeo ◽

Sergi Sanz ◽

Marcus VG Lacerda ◽

...

Keyword(s):

Escherichia Coli ◽

Plasmodium Vivax ◽

Wheat Germ ◽

Suspension Array

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Evaluation of the time resolved fluorescence immunoassay (TRFIA) for the detection of varicella zoster virus (VZV) antibodies following vaccination of healthcare workers

Journal of Virological Methods ◽

10.1016/j.jviromet.2010.12.021 ◽

2011 ◽

Vol 172 (1-2) ◽

pp. 60-65 ◽

Cited By ~ 13

Author(s):

S.L.R. McDonald ◽

P.A.C. Maple ◽

N. Andrews ◽

K.E. Brown ◽

K.L. Ayres ◽

...

Keyword(s):

Varicella Zoster Virus ◽

Healthcare Workers ◽

Fluorescence Immunoassay ◽

Time Resolved Fluorescence ◽

Time Resolved ◽

Varicella Zoster

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Optical transformation of a CdTe quantum dot-based paper sensor for a visual fluorescence immunoassay induced by dissolved silver ions

Journal of Materials Chemistry B ◽

10.1039/c6tb03042d ◽

2017 ◽

Vol 5 (4) ◽

pp. 826-833 ◽

Cited By ~ 49

Author(s):

Zhenzhen Lin ◽

Shuzhen Lv ◽

Kangyao Zhang ◽

Dianping Tang

Keyword(s):

Quantum Dots ◽

Quantum Dot ◽

Cation Exchange ◽

Carcinoembryonic Antigen ◽

Silver Ions ◽

Fluorescence Immunoassay ◽

Cation Exchange Reaction ◽

Optical Transformation ◽

Cdte Quantum Dot ◽

Paper Sensor

This work designs a visual fluorescence immunoassay for carcinoembryonic antigen based on structural and optical transformation of CdTe quantum dots immobilized on paper by cation-exchange reaction.

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Near-Infrared Fluorescence Immunoassay Using Streptavidin-Conjugated Oxygen-Doped Carbon Nanotubes

ECS Meeting Abstracts ◽

10.1149/ma2021-0271896mtgabs ◽

2021 ◽

Vol MA2021-02 (7) ◽

pp. 1896-1896

Author(s):

Keiko Kojima ◽

Yoko Iizumi ◽

Minfang Zhang ◽

Toshiya Okazaki

Keyword(s):

Carbon Nanotubes ◽

Near Infrared ◽

Fluorescence Immunoassay ◽

Near Infrared Fluorescence

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Abstract 4336: Interrogating the Human Myocardial Interstitium during Myocardial Arrest and Reperfusion: Dynamic Changes in Cytokines and Protease Activity

Circulation ◽

10.1161/circ.118.suppl_18.s_867-a ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Robert E Stroud ◽

Christine N Koval ◽

Isabelle Gengler ◽

Anne M Deschamps ◽

John S Ikonomidis ◽

...

Keyword(s):

Detection System ◽

Ischemia Reperfusion ◽

Dynamic Assessment ◽

High Sensitivity ◽

Fluorescent Detection ◽

Suspension Array ◽

Cytokine Analysis ◽

And Function ◽

Inflammatory Molecules ◽

Pulmonary Bypass

Background. Cytokines, such as the interleukins (IL1β, IL2, IL6) and tumor necrosis factor (TNF) can modulate myocardial structure and function with ischemia/reperfusion (I/R) but dynamic assessment of these biological molecules within the human myocardial interstitium with I/R has not been performed, and the inter-relationship to matrix metalloproteinases activity (MMPact) remains unexplored. Accordingly, a fluorogenic microdialysis method was used to simultaneously measure myocardial interstitial cytokine levels and MMPact in patients during and following I/R. Methods . MMPact was measured in patients (n=13) undergoing cardio-pulmonary bypass (CPB) at baseline, during myocardial arrest and CPB (on-CPB), and immediately following reperfusion and separation from CPB (post-CPB) by a validated in-line microdialysis fluorescent detection system. Myocardial interstitial fluid was subjected to cytokine analysis by high sensitivity multiplex suspension array. Results . Interstitial MMPact increased by over 30% post-CPB and was accompanied by a specific change in cytokine profiles (Figure ). The classical pro-inflammatory molecules such as TNF and IL6 were either not detectable or unchanged, whereas IL1β and IL2 which can be proinflammatory, were increased. Conclusions. These unique results demonstrated that a dynamic cytokine signature occurs within the human myocardial interstitium following I/R and is temporally related to heightened MMP activity. Direct interrogation of the human myocardial interstitium may provide a unique insight into critical signaling pathways which may evoke adverse structural and functional events following I/R.

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Abstract 3050: Assessment of Genetic Risk for Thoracic Aortic Aneurysm Among Hypertensive Patients

Circulation ◽

10.1161/circ.116.suppl_16.ii_683-b ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Kimihiko Kato ◽

Mitsutoshi Oguri ◽

Tetsuro Yoshida ◽

Takeshi Hibino ◽

Kazuhiro Yajima ◽

...

Keyword(s):

Risk Factor ◽

Genetic Risk ◽

Odds Ratio ◽

The United States ◽

Multivariable Logistic Regression Analysis ◽

Forward Selection ◽

Structural Formation ◽

Hypertensive Patients ◽

Mortality And Morbidity ◽

Suspension Array

Introduction: Aneurysms and dissections at the thoracic aorta (TAA) are the leading causes of mortality and morbidity in the United States and Japan. Although hypertension is a major risk for TAA, several studies have indicated that genetic factors also influence the structural formation of TAA. The purpose of the present study was to identify gene polymorphisms associated with TAA among hypertensive patients for assessment of the genetic risk for this condition. Methods: This case-control study comprised 1351 hypertensive individuals, including 88 subjects with TAA and 1263 without any cardiovascular complications. The genotypes for 142 polymorphisms of 121 candidate genes were determined by a method that combines the polymerase chain reaction and sequence-specific oligonucleotide probes with suspension array technology. Results: Evaluation of genotype distributions by the chi-square test and subsequent multivariable logistic regression analysis with adjustment for age, sex, body mass index, and prevalence of smoking, diabetes mellitus, hypercholesterolemia, and metabolic syndrome revealed that the T→G (3′ UTR) polymorphism of the thrombospondin 2 gene ( THBS2 ; odds ratio, 4.7) is significantly (P < 0.05) associated with TAA in hypertensive subjects, with the variant G allele representing a risk factor for this condition. Furthermore, the -110A→C polymorphism of heat-shock 70-kD protein 8 gene ( HSPA8 ; odd ratio, 0.3), the C→T (Pro198Leu) polymorphism of the glutathione peroxidase gene ( GPX1 ; odds ratio, 0.3), the -6G→A polymorphism of angiotensin 1 gene ( AGT ; odds ratio, 0.3), and the -850C→T polymorphism of tumor necrosis factor gene ( TNF ; odds ratio, 0.5) were significantly associated with this condition, with the variant allele of each polymorphism being protective against this condition. A stepwise forward selection procedure revealed that polymorphisms of THBS2 , HSPA8 , GPX1 , AGT , and TNF significantly affected the prevalence of TAA. Conclusions: Genetic variant of THBS2 may be a risk factor for TAA in hypertensive patients, whereas variants of HSPA8 , GPX1 , AGT , and TNF may be protective against this condition. Determination of genotypes for these polymorphisms may prove informative for assessment of the genetic risk for TAA.

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