An electrochemical genosensor for Leishmania major detection based on dual effect of immobilization and electrocatalysis of cobalt-zinc ferrite quantum dots.
Identification of Leishmania parasites is important in diagnosis and clinical studies of leishmaniasis. Although epidemiological and clinical methods are available, they are not sufficient for identification of causative agents of leishmaniasis. In the present study, quantum dots of magnetic cobalt-zinc ferrite (Co0.5Zn0.5Fe2O4) were synthesized and characterized by physicochemical methods. The quantum dots were then employed as an electrode modifier to immobilize a 24-mer specific single stranded DNA probe, and fabrication of a label-free, PCR-free and signal-on electrochemical genosensor for the detection of Leishmania major. Hybridization of the complementary single stranded DNA sequence with the probe under the selected conditions was explored using methylene blue as a redox marker, utilizing the electrocatalytic effect of the quantum dots on the methylene blue electroreduction process. The genosensor could detect a synthetic single stranded DNA target in a range of 1.0×10(-11) to 1.0×10(-18)molL(-1) with a limit of detection of 2.0×10(-19)molL(-1), and genomic DNA in a range of 7.31×10(-14) to 7.31×10(-6)ngμL(-1) with a limit of detection of 1.80×10(-14)ngμL(-1) with a high selectivity and sensitivity.
Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran. Electronic address: hheli7@yahoo.com.
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Heli
Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; Department of Medical Physics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
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Sattarahmady
Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran; Basic Sciences in Infectious Diseases Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
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Hatam
Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; Department of Nanomedicine, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran.
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Reisi
Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
R Dehdari
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Vais
D015374:Biosensing Techniques / Q000379:methods; D003035:Cobalt / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000235:genetics; D055664:Electrochemical Techniques / Q000379:methods*; D005290:Ferric Compounds / Q000737:chemistry*; D006801:Humans; D061925:Immobilized Nucleic Acids / Q000737:chemistry* / Q000235:genetics; D018320:Leishmania major / Q000235:genetics / Q000302:isolation & purification*; D016773:Leishmaniasis, Cutaneous / Q000175:diagnosis* / Q000469:parasitology; D057230:Limit of Detection; D009693:Nucleic Acid Hybridization / Q000379:methods; D045663:Quantum Dots / Q000737:chemistry* / Q000648:ultrastructure; D015032:Zinc / Q000737:chemistry*
D004277:DNA, Single-Stranded; D005290:Ferric Compounds; D061925:Immobilized Nucleic Acids; C001215:ferrite; D003035:Cobalt; D015032:Zinc
DNA biosensor; Electrocatalysis; Ferrite; Magnetic nanoparticles; Signal-on genosensor