Ultrasensitive immunoassay of 7-aminoclonazepam in human urine based on CdTe nanoparticle bioconjugations by fabricated microfluidic chip

Biosens Bioelectron. 2009 Mar 15;24(7):2051-6. doi: 10.1016/j.bios.2008.10.015. Epub 2008 Oct 31.

Abstract

The present paper described a rapid and ultrasensitive detection method using a microfluidic chip for analyzing 7-aminoclonazepam (7-ACZP) residues in human urine. A microfluidic chip-based immunoassay with laser-induced fluorescence (LIF) detection based on the water-soluble denatured bovine serum albumin (dBSA)-coated CdTe quantum dots (QDs) was prepared for the ultrasensitive detection of 7-ACZP. The whole procedure including the chip and the control software was designed and constructed in our own laboratory. The detection of 7-ACZP could be completed within 5 min. The results demonstrated that under the optima conditions, 7-ACZP residues could be detected with a precision of 5% relative standard deviation (RSD), and the linear range and the limit of detection (LOD) for 7-ACZP were 1.1-60.1 and 0.021 ngmL(-1), respectively. This method was compared with ELISA and showed a good correlation. This microfluidic chip with LIF detection was applied to the determination of 7-ACZP residues in positive human urine samples, and the results were confirmed by high-performance liquid chromatography and tandem mass spectrometry (LC/MS/MS). This ultrasensitive detection technique was proved to be practical for clinical use.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anticonvulsants / urine
  • Biosensing Techniques / instrumentation
  • Cadmium Compounds / chemistry*
  • Clonazepam / analogs & derivatives*
  • Clonazepam / urine
  • Equipment Design
  • Equipment Failure Analysis
  • Immunoassay / instrumentation*
  • Luminescent Measurements / instrumentation*
  • Microchemistry / instrumentation
  • Microfluidic Analytical Techniques / instrumentation*
  • Microscopy, Fluorescence / instrumentation*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Tellurium / chemistry*
  • Urinalysis / instrumentation*

Substances

  • Anticonvulsants
  • Cadmium Compounds
  • 7-aminoclonazepam
  • Clonazepam
  • Tellurium
  • cadmium telluride