title: Poly(A) Extensions of miRNAs for Amplification-Free Electrochemical Detection on Screen-Printed Gold Electrodes.
abstract: Current amplification-based microRNA (miRNA) detection approaches are limited by the small sizes of miRNAs as well as amplification bias/artifacts. Herein, we report on an amplification-free miRNA assay based on elevated affinity interaction between polyadenylated miRNA and bare gold electrode. The poly(A) extension on the 3' ends of magnetically isolated miRNA targets facilitated high adsorption efficiency onto gold electrode surfaces for electrochemical detection without any cumbersome electrode surface functionalization procedures. The assay showed excellent detection sensitivity (10 fM) and specificity and was demonstrated for quantitative miR-107 detection in human cancer cell lines and clinical urine samples. We believe our assay could be useful as an amplification-free alternative for miRNA detection.
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland , Brisbane, Queensland 4072, Australia.
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Koo
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland , Brisbane, Queensland 4072, Australia.
authors.forename: Laura G
authors.initials: LG
authors.lastname: Carrascosa
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland , Brisbane, Queensland 4072, Australia.
authors.forename: Muhammad J A
authors.initials: MJ
authors.lastname: Shiddiky
authors.affiliation: Centre for Personalized Nanomedicine, Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland , Brisbane, Queensland 4072, Australia.|School of Chemistry and Molecular Biosciences, The University of Queensland , Brisbane, Queensland 4072, Australia.
authors.forename: Matt
authors.initials: M
authors.lastname: Trau
mesh_terms: D015374:Biosensing Techniques; D045744:Cell Line, Tumor; D055664:Electrochemical Techniques; D004566:Electrodes; D005292:Ferricyanides / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D006801:Humans; D061986:MCF-7 Cells; D008280:Magnetics; D035683:MicroRNAs / Q000032:analysis* / Q000302:isolation & purification / Q000652:urine; D011061:Poly A / Q000737:chemistry
chemical_list: D005292:Ferricyanides; D035683:MicroRNAs; C007931:hexacyanoferrate III; D011061:Poly A; D006046:Gold