Sandwich ELISA and immunochromatographic strip of Kunitz trypsin inhibitor using sensitive monoclonal antibodies

A dual-labelled immunoassay using goldmag nanoparticles (GMNPs) and CdTe quantum dots (QDs) was applied for the quantification of casein in milk. In this method, anti-casein monoclonal antibody bound to GMNPs was used as capture probe, and the anti-casein polyclonal antibody, labelled with CdTe QDs, was employed as detection probe. This dual-labelled immunoassay was optimized and applied in the testing of casein content of three brands of commercial milks. The results showed a good linear tendency between casein concentrations and fluorescent intensities in the range of 4.617-289.9 ng/mL, and the half inhibition concentration (IC 50 ) was 36.59 ng/mL. Besides, the recovery rates of this developed immunoassay were in accordance with those in traditional enzyme-linked immunosorbent assay for rapid detection of casein content in commercial milks. It suggested that this dual-labelled immunoassay was reliable, and could provide important theoretical value and practical significance in the identification and quantification of milk allergens. ARTICLE HISTORY

Section: Introductionmentioning

confidence: 99%

Dual-labelled immunoassay with goldmag nanoparticles and quantum dots for quantification of casein in milk

Wang

et al. 2017

“…AA Ⅰ-OVA was used as coating antigen in the ic-ELISA. The procedure for immunization was similar to that used in our previous work (Chen, Li, et al, 2017;Xu et al, 2016a;Xu et al, 2016b). Ic-ELISA was used to screen the mice with the highest serum antibody titre and lowest 50% inhibitory concentration (IC50).…”

Section: Mab Preparationmentioning

confidence: 99%

Development of ic-ELISA and an immunochromatographic strip assay for the detection of aristolochic acid Ⅰ

Song

et al. 2019

Self Cite

“…After this, the solution was centrifuged for 30 min at 20000 rpm, at 4°C (D-37520 Osterode Made in Germany). Finally, the pellet was resuspended in 20 mmol/L Tris (pH 8.2), 0.1% Tween, 0.1% PEG, 5% trehalose, 5% sucrose, 5% Brij and 0.2% BSA) and stored at 4°C Xu et al, 2016).…”

Section: Labelling Mcabs With Colloidal Gold Particlesmentioning

confidence: 99%

Preparation of an anti-4,4′-dinitrocarbanilide monoclonal antibody and its application in an immunochromatographic assay for anticoccidial drugs

Zheng³

et al. 2018

Self Cite

This study outlines the successful development and testing of an immunochromatographic test strip for the detection of the anticoccidial drug, nicarbazin in milk. The preparation and characterization of an anti-4,4 ′-dinitrocarbanilide monoclonal antibody was based on hapten re-4,4 ′-dinitrocarbanilide. The monoclonal antibody was highly specific for 4, 4 ′dinitrocarbanilide, with a half-life inhibitory concentration (IC 50) of 3.46 ng/mL. The detection limit was 0.86 ng/mL. The linear range was 1.71-7 ng/mL. The cutoff values of colloidal gold-based immunochromatographic test paper in phosphate buffered saline (PBS) and in milk were 10 ng/mL, 100 ng/mL, respectively. These results were in good agreement with ELISA analyses and suggest that immunochromatographic test strips are a fast and sensitive method for the semi-quantitative and qualitative analysis of nicarbazin in milk.