• Home
  • Search Results
  • Electrochemical detection of leukemia oncogenes using enzyme-loaded carbon nanotube labels.

Electrochemical detection of leukemia oncogenes using enzyme-loaded carbon nanotube labels.

The Analyst (2014-06-26)
Ai-Cheng Lee, Dan Du, Baowei Chen, Chew-Kiat Heng, Tit-Meng Lim, Yuehe Lin
ABSTRACT

We describe an ultrasensitive electrochemical nucleic acid assay amplified by carbon nanotubes (CNTs)-based labels for the detection of human acute lymphocytic leukemia (ALL)-related p185 BCR-ABL fusion transcript. The carboxylated CNTs were functionalized with horseradish peroxidase (HRP) molecules and target-specific detection probes (DP) via diimide-activated amidation and used to label and amplify the target hybridization signal. The activity of captured HRP was monitored by square-wave voltammetry measuring the electroactive enzymatic product in the presence of 2-aminophenol and hydrogen peroxide substrate solution. The signal-amplified assay achieved a detection limit of 83 fM (5 × 10(-18) mol in 60 μL) targets oligonucleotides and has a 4-order-wide dynamic range of target concentration. The resulting assay allowed robust discrimination between the perfect match and a three-base mismatch sequence. When exposed to the full-length (491 bp) DNA oncogene, the approach demonstrated a detection limit of 1 × 10(-16) mol in 60 μL, corresponding to approximately 33 pg of the target gene. The high sensitivity and specificity of the assay enabled a PCR-free detection of target transcripts in as little as 65 ng of mRNA extracted from positive ALL cell lines SUP-B15 in comparison to those obtained from negative cell line HL-60. The approach enables a simple, low-cost and ultrasensitive electrochemical nucleic acid detection in portable devices, point-of-care and early disease diagnostic applications.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Sodium azide, ReagentPlus®, ≥99.5%
Sigma-Aldrich
Chloroform, contains 100-200 ppm amylenes as stabilizer, ≥99.5%
Sigma-Aldrich
Chloroform, anhydrous, ≥99%, contains 0.5-1.0% ethanol as stabilizer
Sigma-Aldrich
MES, low moisture content, ≥99% (titration)
Sigma-Aldrich
Chloroform, anhydrous, contains amylenes as stabilizer, ≥99%
Sigma-Aldrich
Chloroform, suitable for HPLC, ≥99.8%, contains 0.5-1.0% ethanol as stabilizer
Sigma-Aldrich
Chloroform, HPLC Plus, for HPLC, GC, and residue analysis, ≥99.9%, contains amylenes as stabilizer
Sigma-Aldrich
Phenol solution, BioReagent, Equilibrated with 10 mM Tris HCl, pH 8.0, 1 mM EDTA, for molecular biology
Sigma-Aldrich
Phenol, puriss. p.a., ACS reagent, reag. Ph. Eur., 99.0-100.5%
Sigma-Aldrich
Phenol, for molecular biology
Sigma-Aldrich
Sodium azide, BioXtra
Sigma-Aldrich
Liquified Phenol, ≥89.0%
Sigma-Aldrich
Sodium azide, BioUltra, ≥99.5% (T)
Sigma-Aldrich
Phenol, BioXtra, ≥99.5% (GC)
Sigma-Aldrich
Chloroform, contains ethanol as stabilizer, ACS reagent, ≥99.8%
Sigma-Aldrich
Phenol solution, Saturated with 0.1 M citrate buffer, pH 4.3 ± 0.2, BioReagent, for molecular biology
Sigma-Aldrich
Phenol, ≥99%
Supelco
Phenol, Pharmaceutical Secondary Standard; Certified Reference Material
Sigma-Aldrich
Chloroform, suitable for HPLC, ≥99.8%, amylene stabilized
Sigma-Aldrich
Chloroform, puriss. p.a., reag. ISO, reag. Ph. Eur., 99.0-99.4% (GC)
Sigma-Aldrich
Sodium azide, purum p.a., ≥99.0% (T)
Sigma-Aldrich
Chloroform, contains amylenes as stabilizer, ACS reagent, ≥99.8%
Sigma-Aldrich
Chloroform, HPLC Plus, for HPLC, GC, and residue analysis, ≥99.9%, contains 0.5-1.0% ethanol as stabilizer
Sigma-Aldrich
Phenol, contains hypophosphorous as stabilizer, loose crystals, ACS reagent, ≥99.0%
Sigma-Aldrich
Chloroform, contains ethanol as stabilizer, meets analytical specification of BP, 99-99.4% (GC)
Supelco
Chloroform, analytical standard
Sigma-Aldrich
Chloroform, ACS spectrophotometric grade, ≥99.8%, contains 0.5-1.0% ethanol as stabilizer
Sigma-Aldrich
MES solution, BioUltra, for molecular biology, 0.5 M in H2O
Sigma-Aldrich
Chloroform, ReagentPlus®, ≥99.8%, contains 0.5-1.0% ethanol as stabilizer
Sigma-Aldrich
Phenol, unstabilized, ReagentPlus®, ≥99%