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Title: Quantum dot-based microfluidic biosensor for cancer detection

We report results of the studies relating to fabrication of an impedimetric microfluidic–based nucleic acid sensor for quantification of DNA sequences specific to chronic myelogenous leukemia (CML). The sensor chip is prepared by patterning an indium–tin–oxide (ITO) coated glass substrate via wet chemical etching method followed by sealing with polydimethylsiloxane (PDMS) microchannel for fluid control. The fabricated microfluidic chip comprising of a patterned ITO substrate is modified by depositing cadmium selenide quantum dots (QCdSe) via Langmuir–Blodgett technique. Further, the QCdSe surface has been functionalized with specific DNA probe for CML detection. The probe DNA functionalized QCdSe integrated miniaturized system has been used to monitor target complementary DNA concentration by measuring the interfacial charge transfer resistance via hybridization. The presence of complementary DNA in buffer solution significantly results in decreased electro-conductivity of the interface due to presence of a charge barrier for transport of the redox probe ions. The microfluidic DNA biosensor exhibits improved linearity in the concentration range of 10{sup −15} M to 10{sup −11} M.
Authors:
 [1] ;  [2] ; ;  [1] ;  [3]
  1. Biomedical Instrumentation Section, CSIR-National Physical Laboratory, New Delhi-110012 (India)
  2. (India)
  3. Department of Biotechnology, Delhi Technological University, Delhi-110042 (India)
Publication Date:
OSTI Identifier:
22399067
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 19; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 60 APPLIED LIFE SCIENCES; CADMIUM; CONCENTRATION RATIO; DETECTION; DNA; ETCHING; FLUIDS; GLASS; INDIUM COMPOUNDS; INTERFACES; LEUKEMIA; PROBES; QUANTUM DOTS; SENSORS; SUBSTRATES; SURFACES; TIN OXIDES