A channel-resolved approach coupled with magnet-captured technique for multianalyte chemiluminescent immunoassay

Key Laboratory of Analytical Chemistry for Life Science (Ministry of Education of China), Department of Chemistry, Nanjing University, Nanjing 210093, China.
Biosensors & Bioelectronics (Impact Factor: 6.41). 06/2008; 23(10):1422-8. DOI: 10.1016/j.bios.2007.11.017
Source: PubMed


A concept of channel-resolved multianalyte immunoassay (MAIA) and a semi-automated flow-through chemiluminescent (CL) MAIA system coupled with magnet-captured technique were proposed for rapid quantitation of different analytes in a single run. Using alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA) and carcinoma antigen 125 (CA 125) as model analytes. They were firstly incubated in the mixtures of capture antibodies-immobilized paramagnetic microspheres (PMs) and corresponding alkaline phosphatase-labeled antibodies under stir and pumped into three parallel detection channels, the PMs were simultaneously captured by magnet, and the CL signals from the three channels were then sequentially collected with the aid of optical shutters to perform quantitative detection. AFP, CEA and CA 125 could be rapidly assayed in the ranges of 1.0-40microg/l, 0.20-30microg/l and 1.0-50kU/l with the detection limits of 0.60microg/l, 0.080microg/l and 0.70kU/l at 3sigma, respectively. After manual dispensing of specimen and reagents the whole assay process could be completed in 18min. The assay results of clinical serum samples with the proposed method were in acceptable agreement with the reference values. This system, based on the designed channel-resolved strategy and magnet-captured technique provides a semi-automated, reusable, simple, sensitive, rapid and low-cost approach for MAIA without using of expensive array detector.

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    • "125 1.5 lm, MPs coated with anti – AFP or anti –CEA or anti –CA 125 ALP-labeled antibodies ALP – Sapphire-IITM in Tris-HCl buffer (pH 9.5)– Disodium 3-(4- methoxyspiro{1,2- dioxetane-3,2¢-(5¢chloro) tricycle [,7] decan}-4-yl) phenyl phosphate Sandwich- type 1.0–40 lg L À1 (0.60 lg L À1 ) 0.20–30 lg L À1 (0.080 lg L À1 ) and 1.0– 50 kU L À1 (0.70 kU L À1 ), respectively Human serum [54] a-fetoprotein (AFP) 2 lm, MPs were coated with FITC labeled anti- AFP monoclonal antibody HRP-labeled anti-AFP monoclonal antibody HRP–luminol–H 2 O 2 Sandwich- type 0–2500 ng mL À1 (1.5 ng mL À1 ) Human serum [50] a-fetoprotein (AFP) 3 lm, coated with anti- FITC antibody ALP-labeled anti- AFP antibody ALP with 4-methoxy-4- (3-phosphate-phenyl)- spiro-(1,2-dioxetane- 3,2_-adamantane) (AMPPD) Sandwich- type 0–1200 U mL À1 (3.0 U mL À1 ) Human serum [39] Linear alkylbenzene sulfonates (LAS) 100 lm, MPs coated with anti-LAS monoclonal antibody HRP labeled LAS Luminol – H 2 O 2 – piodophenol – HRP Competitive- type 0–500 ppb (25 ppb a ) N.R. [26] Alkylphenol polyethoxylates (APnEOs) 100 lm, MPs were coated with anti-APnEOs monoclonal antibody HRP labeled APnEOs Luminol – H 2 O 2 – piodophenol – HRP Competitive- type 0–1000 ppb (10 ppb a ) River water samples [27] "
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