Highly sensitive and selective lateral flow immunoassay based on magnetic nanoparticles for quantitative detection of carcinoembryonic antigen

• Published in: Talanta (Oxford) Vol. 161; pp. 205 - 210
• Main Authors: Liu, Fangming, Zhang, Honglian, Wu, Zhenhua, Dong, Haidao, Zhou, Lin, Yang, Dawei, Ge, Yuqing, Jia, Chunping, Liu, Huiying, Jin, Qinghui, Zhao, Jianlong, Zhang, Qiqing, Mao, Hongju
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.12.2016
• Subjects: Antibodies - immunology; Biomarkers, Tumor - blood; Biomarkers, Tumor - immunology; Biotin - chemistry; Carcinoembryonic antigen; Carcinoembryonic Antigen - blood; Carcinoembryonic Antigen - immunology; Diagnosis; DNA, Single-Stranded - chemistry; Humans; Immunoassay - methods; Lateral-flow immunoassay; Limit of Detection; Magnetic nanoparticles; Magnetic Phenomena; Nanoparticles - chemistry; Streptavidin - chemistry; MNPs; LOD; CRP; cTnI; Lateral-flow immunoassay; MRI; HFABP; Magnetic nanoparticles; ECLIA; LFIA; Carcinoembryonic antigen; GMBN; SNR; AuNPs; NC membrane; Diagnosis; CEA; ssDNA
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2016.08.048

Carcinoembryonic antigen (CEA) is an important biomarker in cancer diagnosis. Here, we present an efficient, selective lateral-flow immunoassay (LFIA) based on magnetic nanoparticles (MNPs) for in situ sensitive and accurate point-of-care detection of CEA. Signal amplification mechanism involved linking of detection MNPs with signal MNPs through biotin-modified single-stranded DNA (ssDNA) and streptavidin. To verify the effectiveness of this modified LFIA system, the sensitivity and specificity were evaluated. Sensitivity evaluation showed a broad detection range of 0.25–1000ng/ml for CEA protein by the modified LFIA, and the limit of detection (LOD) of the modified LFIA was 0.25ng/ml, thus producing significant increase in detection threshold compared with the traditional LFIA. The modified LFIA could selectively recognize CEA in presence of several interfering proteins. In addition, this newly developed assay was applied for quantitative detection of CEA in human serum specimens collected from 10 randomly selected patients. The modified LFIA system detected minimum 0.27ng/ml of CEA concentration in serum samples. The results were consistent with the clinical data obtained using commercial electrochemiluminescence immunoassay (ECLIA) (p<0.01). In conclusion, the MNPs based LFIA system not only demonstrated enhanced signal to noise ratio, it also detected CEA with higher sensitivity and selectivity, and thus has great potential to be commercially applied as a sensitive tumor marker filtration system. [Display omitted] •Biotin-streptavidin system is effective in signal enhancement of MNPs based LFIA.•A mathematic relationship between optical density and CEA content is established.•The enhanced LFIA exhibits selectivity in presence of interfering proteins.•There is consistence between our modified LFIA and routinely used ECLIA in hospital.