Quick genotyping detection of HBV by giant magnetoresistive biochip combined with PCR and line probe assay

Abstract

Genotyping of human hepatitis B virus (HBV) can be used to direct clinically effective therapeutic drug-selection. Herein we report that a quick genotyping method for human HBV was established by a specially designed giant magnetoresistive (GMR) biochip combined with magnetic nanoclusters (MNCs), PCR and line probe assay. Magnetic nanoclusters of around 180 nm in diameter were prepared and modified with streptavidin, and resultant streptavidin-modified magnetic nanoclusters were used for capturing biotin-labeled hybrid products on the detection interface of the sensor. The gene fragments of HBV's B and C gene types were obtained by PCR based on a template of B- and C-type plasmids. After gene fragments were hybridized with captured probes, streptavidin-modified magnetic nanoclusters could bind with biotin-conjugated gene fragments, and the resultant hydride products could be quickly detected and distinguished by the GMR sensor, with a detection sensitivity of 200 IU mL(-1) target HBV DNA molecules. The novel method has great potential application in clinical HBV genotyping diagnosis, and can be easily extended to other biomedical applications based on molecular recognition.

Magnetoresistive performance and comparison of supermagnetic nanoparticles on giant magnetoresistive sensor-based detection system

“…Different kinds of ultra-sensitive biosensors have been designed and developed1234567. Chip-based detection of biological agents using giant magnetoresistive (GMR) sensors and magnetic labels have emerged recently8910111213141516, and this GMR sensing technology has the merits of low cost, portability, high sensitivity, and real-time electronic readout. In addition, the fabrication of GMR sensors is compatible with the current large-scale integration technologies, so GMR sensors can be easily integrated and their cost can be greatly reduced as mass production is carried out.…”

Micro Total Analysis Systems: Fundamental Advances and Applications in the Laboratory, Clinic, and Field

“…Giant magnetoresistive sensors were recently used to genotype the four variants of hepatitis B virus, data that may be of clinical relevance in diagnosis and therapy. 134 The ability of μTAS platforms to couple diverse functionalities has been well-demonstrated in genotyping applications. An excellent example incorporated continuous-flow PCR amplification, bioaffinity-based sample purification and concentration, and detection by capillary electrophoresis for gender and ethnicity determination of genetic samples.…”

Microfluidic Biosensing Systems Using Magnetic Nanoparticles

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