Nanomaterials Based Electrochemical Approaches for Biosensing and Bacterial Disinfection.ppt

Nanomaterials Based Electrochemical Approaches for Biosensing and Bacterial Disinfection

1. 1.Introduction
2.Background and Rational
3.Research objectives
4.Experimental details
5.Results and Discussions
6.Summary and Future prospectus
7.Acknowledgements
1
Outline of presentation

2. Introduction
2
Electrochemicalapproachesareconsidereda
physicochemicaldisciplinewithwide-
rangingapplicationsthatareusefulinour
dailylifee.g.sensingtodisinfection(Otaet
al.2014)
Duetotheirpoint-of-careapplications,
electrochemicalapproachesarethemost
promisingcandidatetechnologies.
Sensorsaredeviceswhichcapturethe
physical,chemicalandbiologicalchanges
andconvertchangesintomeasurablesignal
Electrochemicalbiosensorcontaina
biologicalrecognitionelement(enzymes,
proteins,antibodies,nucleicacids)reacts
withtargetanalytesandproduceanelectrical
signal.
substrate product
Reporter
(enzyme)
Apply voltage
Measure current prop.
to concentration of substrate
Electrode ( Transducer)
N. Ronkainen, H. Halsall, W Heineman. Electrochemcial biosensors. Chem. Soc. Rev., 2010, 39, 1747-1763

3. Applications
3
Electrochemical
approaches
Detection of pathogens
( bacteria, viruses)
Testing of bloods (
biochemistry)
Quality control
monitoring
Contamination detection
Food and drug process
monitoring
Diagnosis of plant and
animal diseases
Monitoring of chemicals
Quality control of meat
and plant products
Environmental
Detection of toxic
chemicals in air, water
and soil
Pollutants degradation
and bacterial
disinfection
R.S. Sethi, Biosens. Bioelectron. 9, 243 (1994).
Clinical/Medical
Industrial
Agriculture

4. Role of nanomaterials in electrochemistry
4
Anyparticlesizeinbetween1-100nmare
nanomaterials
Increasethesurface/volumeratio
Reduceddistancese.g.betweenimmobilized
biomoleculesandelectrodes-lowertheresponse
time
EnhancestheproductionofReactiveoxygen
species(ROSs)sufficienttodisinfectbacteriaand
organiccompounds
Similarsizewithbiomoleculescause-intracellular
taggingandidealforbioconjugation
Y.Wang,Z.Tang,N.A.Kotov.MaterialsToday.8,Issue5,Supplement1,20(2005).
W.Kulisch,R.Freudenstein(Eds.),p.3,SpringerVerlag,Dordrecht,TheNetherlands(2009)

5. 5
Background and Rational of thesis
Carbonmaterials,anelementinnature,hasbeen
recognisedbyhumansforalongtime.
DiverseallotropesofCNsfromzero-dimensional
(0D)tothree-dimensional(3D).1,2-nanoscale
Carbonnanomaterials;graphene,carbon
nanotubes(CNTs),carbondots(CDs),carbon
nanofibers(CNFs),nanodiamonds(NDs)and
fullerenes(C60)havebeenextensivelyusedas
electrodematerialsforsensordesign(nanoscale)
CNshaveintrinsicelectrochemicalactivity,high
electricalconductivity,largesurfacearea,easeof
functionalisationand biocompatibility.
(Nanoscale)
Lowcostoffabrication,highstability,fast
responsetimeandspecificdetectionofanalytes
arethekeyrequirementofthebiosensordesign.

6. 6
Contd..
Grapheneisatwo-dimensional(2D),single-
layersheetofSp
2
-hybridizedcarbonatomsthat
arecloselypackedintoahexagonallattice
structure.(small)
Chemicalreductionmethodsvsgreenmethods
forpreparationofgraphene
Studyonnanocompositebehaviourof
graphenematerialswithsinglewalledcarbon
nanotubes-newlevelofcatalyticresponse

7. 7
Contd..
Furtherexploringtheapplicationofnanostrucutredmaterials;the
propertiesofTiO
2havebeeninvestigatedextensivelyfor
photoelectrochemicalbacterialdisinfection.(xin19-20)
Itispromisingphotocatalystduetolowcost,highphotocatalytic
activity,andchemicalstability(17-chenpaper)
Avarietyofelectrocatalystsforanodematerialsincludingcarbon,Pt,
PbO
2,IrO
2,SnO
2,Pt-Ir,andboron-dopeddiamondelectrodeshave
beenextensivelyinvestigatedforelectrocatalyticoxidation(Chen
paper)

8. 8
Quantitativeanalysisofpharmaceuticalsisessentialduringdrug
developmentandclinicaltrialphaseformonitoringbio-availability,
pharmacokineticsandpossibledrugabuse
Acetaminophen(AP)andvalacycloviraretheextensivelyused
analgesicandantiviraldrugs.
GlobalAnalgesicsMarketofAPUS$34.6billionandvalacyclovir
$4.8billionby2017.
Theestimatedincidenceofannualhospitalizationfor
acetaminophenoverdoseinCanadais27to46per100,000persons
Contd..