| Authors | Hossain-Ali Rafiee-Pour, Mohsen Behpour, Mahin Keshavarz |
|---|---|
| Journal | Biosensors and Bioelectronics |
| Page number | 202–207 |
| Volume number | 77 |
| Paper Type | Full Paper |
| Published At | 2016-1-01 |
| Journal Grade | ISI |
| Journal Type | Typographic |
| Journal Country | United Kingdom |
| Journal Index | ISI ,SCOPUS ,PubMed |
Abstract
Small noncodingmicroRNAs(miRNAs)haveemergedasidealnoninvasivebiomarkersforearly-phase
cancer detection.Inthisreport,alabel-freeandsimpleelectrochemicalmiRNAbiosensorisdeveloped
based onemployingmethyleneblue(MB)asaredoxindicator.Thesuccessfullyimmobilizationofthe
single strandDNA(ss-DNA)probeandhybridizationwiththetargetmiRNAsequencewereconfirmed by
electrochemical impedancespectroscopy(EIS)andcyclicvoltammetry(CV)methods.Differentialpulse
voltammetry (DPV)techniquewasusedtorecordtheoxidationpeakcurrentofMBunderoptimal
condition andanincreaseinthepeakcurrentwasobservedafterhybridization.Byemployingthis
strategy,miRNAcandetectinarangefrom0.1to500.0pMwitharelativelylowdetectionlimitof
84.3 fM.TheelectrochemicalresponseofMBonss-DNAandduplexofmiRNA/DNAwascharacterizedby
CV andchronocoulometrymethod.Thelinearrelationbetweentheredoxpeakcurrents(Ip) andscanrate
(ν) indicatesthattheelectrontransfer(ET)betweenMBandtheelectrodesurfacewasmediatedbythe
miRNA/DNA π-stackedduplex.Thevalueofsurfacecoverage(Γ) wascalculatedthatindicatedincrease
amount ofMBonthesurfaceofmodified electrodeafterhybridizationeventandrevealedtheadsorption
of MBatmodified electrodeismonolayer.Also,theelectrontransferrateconstants(ks) ofMBwere
estimated. Theresultsofkineticanalysiswereconfirmed bychronocoulometrymethod.Thedis-
crimination abilityofmiRNAbiosensorevenagainstanoncomplementarytargetwasalsostudied.
Consequently,thisstrategywillbevaluableforsensitive,selectiveandlabel-freedetectionofmiRNA.