Quantitative analysis of total β-subunit of human chorionic gonadotropin concentration in urine by immunomagnetic reduction to assist in the diagnosis of ectopic pregnancy

Abstract

Background The initial diagnosis of ectopic pregnancy depends on physical examination, ultrasound, and serial measurements of total β-subunit of human chorionic gonadotropin (hCGβ) concentrations in serum. The aim of this study was to explore the possibility of using quantitative analysis of total hCGβ in urine rather than in serum by immunomagnetic reduction (IMR) assay as an alternative method to diagnose an ectopic pregnancy. Methods We established a standard calibration curve of IMR intensity against total hCGβ concentration based on standard hCGβ samples, and used an IMR assay to detect total hCGβ concentrations in the urine of pregnant women with lower abdominal pain and/or vaginal bleeding. The final diagnosis of ectopic pregnancy was based on ultrasound scans, operative findings, and pathology reports. In this prospective study, ten clinical samples were used to analyze the relationship of total hCGβ IMR signals between urine and serum. Furthermore, 20 clinical samples were used to analyze the relationship between urine IMR signals and serum levels of total hCGβ. Results The calibration curve extended from 0.01 ng/mL to 10,000 ng/mL with an excellent correlation ( R 2 =0.999). In addition, an excellent correlation of total hCGβ IMR signals between urine and serum was noted ( R 2 =0.994). Furthermore, a high correlation between urine IMR signals and serum levels of total hCGβ was noted ( R 2 =0.862). Conclusion An IMR assay can quantitatively analyze total hCGβ concentrations in urine, and is a potential candidate for point-of-care testing to assist in the diagnosis of ectopic pregnancy.

Homogeneous Biosensing Based on Magnetic Particle Labels

“…In addition to proteins, IMR has also been applied for the sensing of small molecules like hormones, as it has been reported by Chen et al for the detection of the β-subunit of human chorionic gonadotropin in urine samples of pregnant women [ 165 ]. Furthermore, a general proof for the successful detection of DNA by IMR measurements can be found in the publication of Yang et al [ 166 ].…”

A facile and sensitive peptide-modulating graphene oxide nanoribbon catalytic nanoplasmon analytical platform for human chorionic gonadotropin

“…We can see that the RRS analytical system is more sensitive than the Abs and was thus chosen for sample detection. Compared to the reported hCG methods, [25][26][27][28][29][30][31][32][33][34][35][36] this RRS method is not only sensitive and selective but also facile, of low-cost and without nanoparticle aggregation. The clinical method of chemiluminescent immunoassay had a DL of 0.143 ng/mL, limit of quantitation (LQ) of 5 ng/mL and linear range of 5-540 ng/mL hCG; 37 the DL and LQ of this RRS method are better than the clinical method, and the linear range of the two methods are close to each other, as the upper LQ divided by the lower LQ is 108 and 100, respectively.…”

“…Recently, some new assays were developed for the detection of hCG. [31][32][33][34][35][36] Zhao et al 31 reported a microplate magnetic chemiluminescence enzyme immunoassay for the determination of hCG using the alkaline phosphatase (ALP) as a labeled reagent and 3-(2′-spiroadamantane)-4-methoxy-4-(3″-phosphoryloxy) phenyl-1,2-dioxetane (AMPPD) as a chemiluminescence reagent. Chang et al 32 combined catalytic gold nanoparticles with an hCG-specific peptide aptamer to create a simple, sensitive, label-free colorimetric assay for hCG.…”

“…Lei et al 34 reported a strategy of chemiluminescence resonance energy transfer for detection of 0.12 nmol/mL hCG using graphene as an efficient long-range energy acceptor and the magnetic nanoparticles for magnetic separation and immobilization of HRP-labeled anti-hCG antibody. Chen et al 35 reported an immunomagnetic assay for quantitative analysis of total β-subunit of hCG concentration in urine. The peptide of hCG was more stable than hCG antibody.…”

MicroRNAs as clinical biomarkers?

“…Extracellular biomarkers are often but not always linked with less invasive sampling, for example the withdrawal of a peripheral venous blood sample or urine collection. Examples are urine test for beta-human chorionic gonadotrophin (Chen et al, 2015 ) as an indicator of pregnancy or prostate specific antigen (PSA) (Ravery, 1999 ) in a suspected prostate cancer case.…”