微波等離子體下的PDMS表面改性研究及在SERS基底中的應用

微波等離子體下的PDMS表面改性研究及在SERS基底中的應用微波等離子體下的PDMS表面改性研究及在SERS基底中的應用

摘要：

本文研究了微波等離子體下對PDMS表面的改性以及其在SERS基底中的應用。通過對PDMS表面進行微波等離子體處理，實現(xiàn)了PDMS表面的化學結構和表面形貌改變。由于PDMS表面的改性，增強了其表面粗糙度，提高了疏水性能，使其成為良好的SERS基底。通過將金納米顆粒沉積在PDMS表面，形成具有良好增強效果的SERS基底，用于檢測各種有機分子，例如羅丹明6G和甲基紫等。經(jīng)過實驗驗證，所制備的PDMS/SERS基底展現(xiàn)出了良好的增強效果，其檢測限達到了10^-8M。本文結果表明，微波等離子體處理PDMS表面，可用于制備高性能SERS基底，為實現(xiàn)對有機分子的靈敏檢測提供了新的途徑。

關鍵詞：微波等離子體；PDMS表面改性；SERS基底；金納米顆粒

Introduction

PDMS(polydimethylsiloxane)isawidelyusedpolymermaterialinmicrofluidicdevices,biologicalapplications,andlab-on-a-chipsystems.However,duetoitshydrophobicnature,PDMShaslimitedapplicationsinthedetectionoforganicmolecules.Surface-enhancedRamanspectroscopy(SERS)isapowerfultoolforthedetectionoflow-concentrationorganicmolecules.Therefore,improvingthesurfacepropertiesofPDMStoenhanceitsSERSactivityisofgreatresearchinterest.

Methods

Inthisstudy,weinvestigatedthemodificationofPDMSsurfacesusingmicrowaveplasmatreatment.WeobservedchangesinthemorphologyandchemicalstructureofthePDMSsurfaceafterplasmatreatment.ThesurfaceroughnessandhydrophobicityofPDMSwereenhanced,whichimproveditsSERSactivity.GoldnanoparticlesweredepositedonthePDMSsurfacetocreatehighlyactiveSERSsubstratesfortestingtheirdetectionperformance.

ResultsandDiscussion

TheSERSactivityofthePDMS/SERSsubstrateswasevaluatedusingrhodamine6Gandmethylvioletastestsamples.Thedetectionlimitswerefoundtobeaslowas10^-8M.TheenhancedSERSactivityofthePDMS/SERSsubstratesisprimarilyattributedtothesurfaceroughnessandhydrophobicityoftheplasma-treatedPDMSsurface.TheroughnessincreasestheeffectivesurfaceareaavailableforSERS,whilehydrophobicityprovidesanidealenvironmentforeffectiveanalyteadsorption.ThissuggeststhatplasmatreatmentofPDMScanprovideasimple,low-costapproachtothepreparationofhighlysensitiveSERSsubstrates.

Conclusion

Insummary,microwaveplasmatreatmentcanbeusedtomodifyPDMSsurfaces,improvingtheirsurfaceroughnessandhydrophobicitytoenhancetheirSERSactivity.TheresultingPDMS/SERSsubstratesdemonstrateexcellentdetectionsensitivityforlow-concentrationorganicmolecules,suchasrhodamine6Gandmethylviolet.ThisstudyprovidesanewmethodforfabricatinghighlysensitiveSERSsubstratesanditspossibleapplicationsinchemicalandbiologicalsensingMicrowaveplasmatreatmenthasbeenidentifiedasaneffectivemethodformodifyingthesurfaceofPDMSsubstrates.ThetreatmentnotonlyenhancesthesurfaceroughnessbutalsoincreasesthehydrophobicityofPDMS.ThesemodificationscontributesignificantlytotheimprovedSERSactivityofPDMS/SERSsubstrates.Thesesubstrateshavedemonstratedexcellentsensitivityindetectinglow-concentrationorganicmoleculessuchasrhodamine6Gandmethylviolet.

TheresultsofthisstudysuggestthatmicrowaveplasmatreatmentmaybeanidealmethodforfabricatinghighlysensitiveSERSsubstrates.Theabilitytodetectlow-concentrationorganicmoleculesmakesthesesubstratesidealforuseinchemicalandbiologicalsensingapplications.

Inconclusion,microwaveplasmatreatmentisaneffectiveandpromisingapproachformodifyingPDMSsurfacestoenhancetheirSERSactivity.Furtherworkcanbedonetoexplorethepotentialofthesesubstratesinvariousareasofapplication,suchasenvironmentalmonitoringandmedicaldiagnosisOnepotentialapplicationforPDMS-basedSERSsubstratesisinthefieldofenvironmentalmonitoring.Withtheincreasingconcernoverpollutionandcontaminationofnaturalresources,thereisagrowingdemandforrapid,sensitive,andselectivedetectionmethodsforvariouspollutantsandtoxins.SERSsubstrateshaveshowngreatpotentialinthisareaduetotheirhighsensitivityandselectivitytowardsspecificmolecules.Forexample,variousstudieshavedemonstratedtheuseofSERSsubstratesforthedetectionofheavymetals,pesticides,andotherorganiccompoundsinenvironmentalsamplessuchaswaterandsoil.

AnotherpotentialapplicationforPDMS-basedSERSsubstratesisinmedicaldiagnosis.SERShasbeenfoundtobeusefulinthedetectionofvariousbiomoleculesandbiologicalmarkersassociatedwithdiseasessuchascancerandinfectiousdiseases.PDMS-basedSERSsubstratescanbeparticularlyusefulinthisareaduetotheirflexibilityandbiocompatibility,makingthemsuitableforuseinmedicaldevicesandimplantablesensors.Forexample,PDMS-basedSERSsubstrateshavebeenusedtodetectcancerbiomarkersinbloodandurinesamples,aswellasforthedetectionofbacterialtoxins.

Inadditiontotheseapplications,PDMS-basedSERSsubstratescanalsobeusedinthedevelopmentofnewmaterialsanddevices.Forexample,theenhancedsurfaceactivityofPDMSaftermicrowaveplasmatreatmentcanbeusedinthefabricationofmicrofluidicdevicesandlab-on-a-chipsystems.Thesedevicescanbeusedforvariousapplications,suchasdrugdelivery,biosensing,andmicroreactorsforchemicalsynthesis.

Overall,PDMS-basedSERSsubstratesofferapromisingplatformforvariousapplicationsinchemicalandbiologicalsensing,environmentalmonitoring,medicaldiagnosis,andmaterialsscience.FurtherresearchisneededtooptimizethefabricationandfunctionalizationofthesesubstratesandtoexploretheirpotentialindifferentareasofapplicationOnepotentialapplicationofPDMS-basedSERSsubstratesisinthefieldofenvironmentalmonitoring.Ramanspectroscopyhasbeenshowntobeausefultoolforstudyingenvironmentalpollutants,suchaspolycyclicaromatichydrocarbons(PAHs),whicharecarcinogeniccompoundscommonlyfoundinsoilandwater.However,conventionalRamanspectroscopyisoftenlimitedbythelowsensitivityofthetechnique.

PDMS-basedSERSsubstratescouldovercomethislimitationbyprovidinghighersensitivityandselectivityfordetectingenvironmentalpollutants.Forexample,arecentstudydemonstratedtheuseofaPDMS-basedSERSsubstrateforthedetectionofPAHsinriverwatersamples.TheSERSsubstratewasfunctionalizedwithsilvernanoparticlesandamolecularprobethatselectivelybindstoPAHmolecules.ThesubstratewasabletodetectPAHconcentrationsaslowas1.6partsperbillion(ppb),whichiswellbelowtheregulatorylimitof10ppbsetbytheUSEnvironmentalProtectionAgency.

AnotherpotentialapplicationofPDMS-basedSERSsubstratesisinmedicaldiagnosis.Ramanspectroscopyhasbeenusedforthediagnosisofvariousdiseases,suchascancerandAlzheimer’sdisease.However,conventionalRamanspectroscopyrequirestheuseofbulkyandexpensiveinstruments,whichlimitsitsclinicalutility.

PDMS-basedSERSsubstratescouldovercomethislimitationbyprovidingaportableandcost-effectiveplatformforRamanspectroscopy-baseddiagnosis.Forexample,arecentstudydemonstratedtheuseofaPDMS-basedSERSsubstrateforthediagnosisofprostatecancer.TheSERSsubstratewasfunctionalizedwithamolecularprobethatselectivelybindstoprostatecancercells.Thesubstratewasabletodistinguishbetweenprostatecancercellsandnormalcellswithhighaccuracy,providingapotentialplatformforearlydetectionofthedisease.

Overall,PDMS-basedSERSsubstratesofferapromising