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Ngokuphuhliswa kwezixhobo ezitsha ze-ultra-soft kwizixhobo zonyango kunye nokusetyenziswa kwe-biomedical, ukuchazwa ngokubanzi kweempawu zabo zomzimba kunye noomatshini zibalulekile kwaye zinzima.Ubuchule be-atomic force microscopy (AFM) obulungisiweyo be-nanoindentation busetyenzisiwe ukubonisa imodyuli yomphezulu ephantsi kakhulu yelehfilcon entsha I-biomimetic silicone hydrogel lens yoqhagamshelwano eqatywe umaleko wezakhiwo zebrashi yepolymer enegatsha.Le ndlela ivumela ukuzimisela okuchanekileyo kwamanqaku oqhagamshelwano ngaphandle kwemiphumo ye-viscous extrusion xa usondela kwiipolymers zebranched.Ukongezelela, kwenza kube lula ukumisela iimpawu zemishini yezinto zebrashi zomntu ngaphandle kwempembelelo ye-poroelasticity.Oku kuphunyezwa ngokukhetha i-AFM probe enoyilo (ubungakanani bencam, ijometri kunye nesantya sentwasahlobo) esilungele ngokukodwa ukulinganisa iimpawu zemathiriyeli ethambileyo kunye neesampuli zebhayoloji.Le ndlela iphucula ubuntununtunu kunye nokuchaneka komlinganiselo ochanekileyo wezinto ezithambileyo kakhulu i-lehfilcon A, enemodyuli ephantsi kakhulu yokunwebeka kwindawo ephezulu (ukuya kwi-2 kPa) kunye nokunwebeka okuphezulu kakhulu ngaphakathi (malunga ne-100%) kubume bendalo enamanzi. .Iziphumo zesifundo somphezulu azizange zibonise kuphela iipropati ze-ultra-soft surface ze-lehfilcon A lens, kodwa zibonise ukuba imodyuli yeebrashi ze-polymer ze-branched yayifaniswa ne-silicon-hydrogen substrate.Le ndlela yokulinganisa umphezulu ingasetyenziswa kwezinye izinto ezithambileyo kakhulu kunye nezixhobo zonyango.
Iimpawu zomatshini wezinto ezilungiselelwe ukudibana ngokuthe ngqo kunye nezicubu eziphilayo zihlala zigqitywa yimeko yebhayoloji.Umdlalo ogqibeleleyo wale mpahla yezinto eziphathekayo unceda ukufezekisa iimpawu zeklinikhi ezifunwayo zezinto ngaphandle kokubangela iimpendulo ezimbi zeselula1,2,3.Kwizinto ezininzi ezilinganayo, ukubonakaliswa kweempawu zoomatshini kulula ngenxa yokufumaneka kweenkqubo ezisemgangathweni kunye neendlela zokuvavanya (umzekelo, i-microindentation4,5,6).Nangona kunjalo, kwizinto ezithambileyo ezinje ngejeli, ii-hydrogels, ii-biopolymers, iiseli eziphilayo, njl.njl., ezi ndlela zovavanyo ngokubanzi azisebenzi ngenxa yokulinganiselwa kwesisombululo somlinganiselo kunye nokungahoyi kwezinye izinto7.Ukutyhubela iminyaka, iindlela zendabuko ze-indentation ziye zatshintshwa kwaye zatshintshwa ukuze zibonakalise uluhlu olubanzi lwezinto ezithambileyo, kodwa iindlela ezininzi zisabandezeleka ngenxa yeentsilelo ezinzulu ezinciphisa ukusetyenziswa kwazo8,9,10,11,12,13.Ukunqongophala kweendlela zovavanyo ezikhethekileyo ezinokuthi zibonakalise ngokuchanekileyo nangokuthembekileyo iipropathi zoomatshini bezixhobo zesupersoft kunye neengqimba zomphezulu zinciphisa kakhulu ukusetyenziswa kwazo kwizicelo ezahlukeneyo.
Kumsebenzi wethu wangaphambili, sazise i-lehfilcon A (CL) lens yoqhagamshelwano, imathiriyeli ethambileyo ene-heterogeneous enazo zonke iipropathi zomphezulu ezithambileyo ezithathwe kuyilo olunokubakho lwe-biomimetic oluphefumlelwe ngumphezulu we-cornea yeliso.Le biomaterial yaphuhliswa ngokuxhunyelelwa i-branched, i-cross-linked polymer layer ye-poly (2-methacryloyloxyethylphosphorylcholine (MPC)) (PMPC) kwi-silicone hydrogel (SiHy) 15 eyenzelwe izixhobo zonyango ezisekelwe kuyo.Le nkqubo yokuxhunyelelwa idala umaleko kumphezulu oquka ibrashi ethambileyo kakhulu kunye nelastiki yepolymeric.Umsebenzi wethu wangaphambili uqinisekisile ukuba isakhiwo se-biomimetic se-lehfilcon A CL sibonelela ngeempawu eziphezulu eziphezulu ezifana nokuphuculwa kokumanzisa kunye nokuthintela ukungcola, ukunyuka kwe-lubricity, kunye nokunciphisa iseli kunye ne-bacterial adhesion15,16.Ukongeza, ukusetyenziswa kunye nokuphuhliswa kwesi sixhobo se-biomimetic sikwacebisa ukwandiswa okungakumbi kwezinye izixhobo ze-biomedical.Ngoko ke, kubalulekile ukubonakalisa iimpawu zomphezulu wale nto i-ultra-soft kwaye uqonde ukusebenzisana kwayo ngoomatshini kunye neso ukwenzela ukudala isiseko solwazi olubanzi ukuxhasa uphuhliso oluzayo kunye nezicelo.Uninzi lwee-lens zoqhagamshelwano ze-SiHy ezithengiswayo zenziwe ngomxube we-homogeneous we-hydrophilic kunye ne-hydrophobic polymers eyenza i-uniform material structure17.Uphononongo oluninzi luye lwenziwa ukuphanda iipropathi zabo zoomatshini kusetyenziswa ukucinezelwa kwemveli, ukunyanzeliswa kunye neendlela zovavanyo lwe-microindentation18,19,20,21.Nangona kunjalo, idizayini ye-biomimetic yenoveli ye-lehfilcon A CL yenza kube yinto ekhethekileyo ye-heterogeneous apho iipropathi ze-mechanical ze-branched polymer brush structures zihluke kakhulu kwezo ze-SiHy base substrate.Ngoko ke, kunzima kakhulu ukulinganisa ngokuchanekileyo ezi mpawu usebenzisa iindlela eziqhelekileyo kunye ne-indentation.Indlela ethembisayo isebenzisa indlela yokuvavanya i-nanoindentation ephunyezwe kwi-atomic force microscopy (AFM), indlela esetyenzisiweyo ukumisela iimpawu zomatshini wezinto ezithambileyo ze-viscoelastic ezifana neeseli zebhayoloji kunye nezicubu, kunye neepolymers ezithambileyo22,23,24,25 .,26,27,28,29,30.Kwi-AFM nanoindentation, izinto ezisisiseko zovavanyo lwe-nanoindentation zidityaniswe nenkqubela phambili yamva nje kwitekhnoloji ye-AFM ukubonelela ngovakalelo lomlinganiselo owandisiweyo kunye novavanyo loluhlu olubanzi lwezinto ezibonakalayo ze-supersoft31,32,33,34,35,36.Ukongeza, itekhnoloji inika ezinye izibonelelo ezibalulekileyo ngokusetyenziswa kweejometri ezahlukeneyo.I-indenter kunye ne-probe kunye nokwenzeka kovavanyo kumajelo ohlukeneyo olwelo.
I-AFM nanoindentation inokwahlulwa ngokwemiqathango ibe ngamacandelo amathathu aphambili: (1) izixhobo (i-sensor, detectors, probes, njl.);(2) iiparamitha zokulinganisa (njengamandla, ukufuduswa, isantya, ubungakanani berempu, njl.);(3) Ukulungiswa kwedatha (ulungiso olusisiseko, ukuqikelelwa kwendawo yokuchukumisa, ukufakwa kwedatha, imodeli, njl.).Ingxaki ebalulekileyo ngale ndlela kukuba izifundo ezininzi kwiincwadi zisebenzisa i-AFM nanoindentation ingxelo ehluke kakhulu kwiziphumo zobungakanani besampuli efanayo / iseli / uhlobo lwezinto37,38,39,40,41.Ngokomzekelo, uLekka et al.Impembelelo ye-AFM probe geometry kwimodyuli elinganiselweyo ye-Young's yeesampulu ze-hydrogel ene-homogeneous ngomatshini kunye neeseli ezingafaniyo zafundwa kwaye zathelekiswa.Banika ingxelo yokuba amaxabiso emodulus axhomekeke kakhulu ekukhethweni kwe-cantilever kunye nokumila kwencam, enexabiso eliphezulu leprobe emile okwephiramidi kunye nelona xabiso liphantsi le-42 leprobe engqukuva.Ngokufanayo, uSelhuber-Unkel et al.Kuye kwaboniswa ukuba isantya se-indenter, ubukhulu be-indenter kunye nobukhulu beesampuli ze-polyacrylamide (PAAM) zichaphazela i-Young's modulus elinganiswe yi-ACM43 nanoindentation.Enye into enzima kukungabikho komgangatho ophantsi kakhulu wemathiriyeli yovavanyo kunye neenkqubo zovavanyo lwasimahla.Oku kwenza kube nzima kakhulu ukufumana iziphumo ezichanekileyo ngokuzithemba.Nangona kunjalo, indlela iluncedo kakhulu kwimilinganiselo ehambelanayo kunye nokuvavanya okuthelekisayo phakathi kweentlobo zesampuli ezifanayo, umzekelo usebenzisa i-AFM nanoindentation ukuhlula iiseli eziqhelekileyo kwiiseli zomhlaza 44, 45.
Xa uvavanya imathiriyeli ethambileyo nge-AFM nanoindentation, umthetho jikelele wobhontsi kukusebenzisa i-probe ene-low spring constant (k) ehambelana ngokusondeleyo nemodyuli yesampulu kunye ne-hemispherical/round tip ukuze i-probe yokuqala ingayigqobhozi imiphezulu yesampulu. uqhagamshelwano lokuqala ngezinto ezithambileyo.Kwakhona kubalulekile ukuba isignali yokuphambuka eyenziwa yi-probe ibe yomelele ngokwaneleyo ukuba ibonwe yi-laser detector system24,34,46,47.Kwimeko yeeseli ze-ultra-soft heterogeneous, izicubu kunye neegels, omnye umngeni kukunqoba amandla okubambelela phakathi kweprobe kunye nomgangatho wesampulu ukuze kuqinisekiswe imilinganiselo yokuvelisa kunye nokuthembekileyo48,49,50.Kuze kube kutshanje, umsebenzi omninzi kwi-AFM nanoindentation ugxininise ekufundweni kokuziphatha komatshini weeseli zebhayoloji, izicubu, iigels, i-hydrogels, kunye ne-biomolecules zisebenzisa ii-probes ezinkulu ze-spherical, ezibizwa ngokuba yi-colloidal probes (CPs)., 47, 51, 52, 53, 54, 55. Ezi ngcebiso zine-radius ye-1 ukuya kwi-50 µm kwaye zenziwe ngeglasi ye-borosilicate, i-polymethyl methacrylate (PMMA), i-polystyrene (PS), i-silicon dioxide (SiO2) kunye ne-diamond- njengekhabhoni (DLC) .Nangona i-CP-AFM i-nanoindentation idla ngokuba yinto yokuqala yokukhetha ukulinganiswa kwesampulu ethambileyo, ineengxaki zayo kunye nemida.Ukusetyenziswa kweengcebiso ezinkulu, ezinobungakanani be-micron-spherical kwandisa indawo yokunxibelelana yencam kunye nesampulu kwaye kukhokelela kwilahleko enkulu yesisombululo sendawo.Kwimizekelo ethambileyo, engabonakaliyo, apho iimpawu zomatshini zezinto zendawo zingahluka kakhulu ukusuka kumyinge kwindawo ebanzi, i-CP indentation inokufihla nayiphi na inhomogeneity kwiipropati kwi-scale52 yendawo.I-Colloidal probes iqhele ukwenziwa ngokuncamathisela i-micron-ubungakanani be-colloidal spheres kwii-cantilevers ezingenazo iincam zisebenzisa i-epoxy adhesives.Inkqubo yokwenziwa kwemveliso ngokwayo izele ziingxaki ezininzi kwaye inokukhokelela ekungahambelani kwenkqubo yokulinganisa iprobe.Ukongezelela, ubungakanani kunye nobuninzi beengqungquthela ze-colloidal zichaphazela ngokuthe ngqo iiparitha eziphambili zokulinganisa i-cantilever, njenge-resonant frequency, ukuqina kwentwasahlobo, kunye ne-deflection sensitivity56,57,58.Ngaloo ndlela, iindlela eziqhelekileyo ezisetyenziswayo kwiiprobes eziqhelekileyo ze-AFM, ezifana nokulinganisa ubushushu, azinako ukunika ulungelelwaniso oluchanekileyo lwe-CP, kwaye ezinye iindlela zingafuneka ukuba zenze ezi zilungiso57, 59, 60, 61. Iimvavanyo ze-CP ze-indentation eziqhelekileyo zisebenzisa ukuphambuka okukhulu kwi-cantilever ukuya funda iipropathi zeesampulu ezithambileyo, ezidala enye ingxaki xa ulinganisa indlela yokuziphatha engahambelaniyo ye-cantilever ngokunxaxha okukhulu62,63,64.Iindlela ze-colloidal probe indentation zanamhlanje zihlala ziqwalasela i-geometry ye-cantilever esetyenziselwa ukulinganisa i-probe, kodwa ungayihoyi impembelelo ye-colloidal particles, eyenza ukungaqiniseki okongezelelweyo ekuchanekeni kwendlela38,61.Ngokufanayo, i-moduli e-elastic ebalwa ngokulinganisa imodeli yoqhagamshelwano ixhomekeke ngokuthe ngqo kwijometri ye-indentation probe, kunye nokungahambi kakuhle phakathi kwe-tip kunye neempawu zomphezulu wesampula kunokukhokelela ekungalungiyo27, 65, 66, 67, 68. Omnye umsebenzi wamva nje nguSpencer et al.Imiba ekufuneka ithathelwe ingqalelo xa ibonakalisa iibrashi zepolymer ezithambileyo zisebenzisa indlela ye-CP-AFM ye-nanoindentation igxininisiwe.Bachaza ukuba ukugcinwa kwe-viscous fluid kwiibrashi ze-polymer njengomsebenzi wesantya kubangela ukwanda kwentloko yokulayisha kwaye ngoko ke imilinganiselo eyahlukeneyo yeempawu ezixhomekeke kwisantya30,69,70,71.
Kolu phononongo, siye sabonakalisa imodyuli yomphezulu we-ultra-soft kakhulu elastic material lehfilcon A CL usebenzisa indlela ye-AFM nanoindentation elungisiweyo.Ukunikezelwa kweempawu kunye nesakhiwo esitsha sale nto, uluhlu lobuntununtunu bendlela yendabuko ye-indentation alwanelanga ngokucacileyo ukubonakalisa i-modulus yale nto ithambileyo kakhulu, ngoko ke kuyimfuneko ukusebenzisa indlela ye-AFM ye-nanoindentation kunye novelwano oluphezulu kunye nobuthathaka obuphantsi.inqanaba.Emva kokuphonononga iintsilelo kunye neengxaki zeendlela ezikhoyo ze-colloidal AFM probe nanoindentation, sibonisa ukuba kutheni sikhethe i-probe ye-AFM encinci, eyenzelwe ngokwezifiso ukuphelisa ubuntununtunu, ingxolo yangasemva, i-pinpoint point of contact, ukulinganisa i-modulus ye-velocity ye-soft heterogeneous materials ezifana nokugcinwa kwamanzi. ukuxhomekeka.kunye nobungakanani obuchanekileyo.Ukongeza, siye sakwazi ukulinganisa ngokuchanekileyo imilo kunye nemilinganiselo yencam ye-indentation, esivumela ukuba sisebenzise imodeli ye-cone-sphere fit ukugqiba imodyuli ye-elasticity ngaphandle kokuvavanya indawo yoqhagamshelwano ye-tip kunye nezinto.Iingqikelelo ezimbini ezingacacanga ezibalwe kulo msebenzi ziimpawu zemathiriyeli ezinwebekayo ngokupheleleyo kunye nemodyuli ezimeleyo yobunzulu be-indentation.Sisebenzisa le ndlela, saqala savavanya imigangatho ethambileyo ethambileyo ngemodyuli eyaziwayo yokulinganisa indlela, emva koko sasebenzisa le ndlela ukubonisa umphezulu wezinto ezimbini ezahlukeneyo zoqhagamshelwano.Le ndlela yokubonakalisa iindawo ze-AFM ze-nanoindentation kunye novakalelo olwandisiweyo kulindeleke ukuba lusetyenziswe kuluhlu olubanzi lwezixhobo ze-biomimetic heterogeneous ultrasoft ezinokusetyenziswa kwizixhobo zonyango kunye nezicelo ze-biomedical.
I-Lehfilcon A iilensi zoqhagamshelwano (i-Alcon, i-Fort Worth, i-Texas, i-USA) kunye ne-silicone substrates zabo ze-hydrogel zikhethwe kwiimvavanyo ze-nanoindentation.I-lens eyilwe ngokukodwa isetyenziswe kuvavanyo.Ukufakela i-lens yokuvavanya, ibekwe ngononophelo kwi-stand-shaped stand, iqinisekisa ukuba akukho maqamza omoya angena ngaphakathi, kwaye agxininiswe ngamaphethelo.Umngxuma kwindawo ephezulu yomphathi we-lens unikezela ukufikelela kwiziko le-optical lens kwiimvavanyo ze-nanoindentation ngelixa ubambe ulwelo kwindawo.Oku kugcina iilensi zimanzi ngokupheleleyo.I-500 μl yesisombululo sokupakisha i-lens yasetyenziswa njengesisombululo sovavanyo.Ukuqinisekisa iziphumo zobungakanani, i-polyacrylamide (PAAM) ekhoyo ngokurhweba engasetyenziswanga (PAAM) hydrogels yalungiswa ukusuka kwi-polyacrylamide-co-methylene-bisacrylamide ukwakheka (100 mm Petrisoft Petri izitya, iMatrigen, Irvine, CA, USA), imodyuli eyaziwayo ye-elastic ye-1. kPa.Sebenzisa i-4-5 yehla (malunga ne-125 µl) ye-phosphate buffered saline (PBS esuka kwi-Corning Life Sciences, Tewkesbury, MA, USA) kunye ne-1 drop of OPTI-FREE Puremoist contact lens solution (Alcon, Vaud, TX, USA).) kwi-AFM hydrogel-probe interface.
Iisampulu zeLehfilcon A CL kunye ne-SiHy substrates zabonwa kusetyenziswa inkqubo yeFEI Quanta 250 Field Emission Scanning Electron Microscope (FEG SEM) exhotyiswe ngeScanning Transmission Electron Microscope (STEM) detector.Ukulungiselela iisampulu, iilensi ziqale zihlanjwe ngamanzi kwaye zisikwe zibe ngamacangca amile okwephayi.Ukufezekisa ulwahlulo olwahlukileyo phakathi kwecandelo le-hydrophilic kunye ne-hydrophobic yeesampuli, isisombululo se-0.10% esizinzile se-RuO4 sisetyenziswe njengedayi, apho iisampulu zacwiliswa kwi-30 min.I-lehfilcon A CL RuO4 staining ibalulekile kungekuphela nje ukuphumeza ukuchasana okuphuculweyo okuphuculweyo, kodwa inceda nokugcina ulwakhiwo lweebrashi zepolymer zebranched kwimo yazo yokuqala, ezithi zibonakale kwimifanekiso ye-STEM.Emva koko zahlanjwa kwaye zachithwa kuluhlu lwemixube ye-ethanol / amanzi kunye nokunyuka kwe-ethanol.Iisampuli zaye zaphoswa nge-EMBed 812/Araldite epoxy, eyaphilisa ngobusuku kwi-70 ° C.Iibhloko zesampuli ezifunyenwe nge-resin polymerization zinqunywe nge-ultramicrotome, kwaye amacandelo amancinci aphunyeziweyo abonakaliswe nge-STEM detector kwimodi yokucoca ephantsi kwi-voltage ekhawulezayo ye-30 kV.Inkqubo efanayo ye-SEM isetyenziselwe ukuchazwa kweenkcukacha zePFQNM-LC-A-CAL AFM probe (Bruker Nano, Santa Barbara, CA, USA).Imifanekiso ye-SEM yeprobe ye-AFM ifunyenwe kwimowudi yevacuum ephezulu eqhelekileyo kunye nombane okhawulezayo wama-30 kV.Fumana imifanekiso kwii-engile ezahlukeneyo kunye nokwandisa ukurekhoda zonke iinkcukacha zemilo kunye nobukhulu be-tip probe ye-AFM.Zonke iincam zomdla kwimifanekiso zilinganiswe ngedijithali.
I-Dimension FastScan Bio Icon ye-atomic force microscope (i-Bruker Nano, i-Santa Barbara, i-CA, i-USA) enemodi ye-"PeakForce QNM kwi-Fluid" yayisetyenziselwa ukujonga kunye ne-nanoindentate lehfilcon A CL, i-substrate ye-SiHy, kunye neesampuli ze-hydrogel ze-PAAm.Ukuvavanya imifanekiso, i-PEAKFORCE-HIRS-FA probe (i-Bruker) ene-radius ye-tip ye-1 nm yayisetyenziselwa ukubamba imifanekiso ephezulu yesampuli kwizinga lokuskena kwe-0.50 Hz.Yonke imifanekiso ithathwe kwisisombululo esimanzi.
Uvavanyo lwe-AFM lwe-nanoindentation lwenziwa kusetyenziswa i-PFQNM-LC-A-CAL probe (Bruker).I-AFM probe inencam yesilicon kwi-nitride cantilever 345 nm ubukhulu, 54 µm ubude kunye ne-4.5 µm ububanzi kunye ne-resonant frequency ye-45 kHz.Yenzelwe ngokukodwa ukubonisa kunye nokwenza imilinganiselo yobuninzi be-nanomechanical kwiisampuli zebhayoloji ezithambileyo.Abenzi boluvo balungelelaniswa ngokwahlukeneyo kumzi-mveliso kunye nezicwangciso ezilinganiswe kwangaphambili zasentwasahlobo.Iingqungquthela zentwasahlobo zeprobes ezisetyenzisiweyo kulolu cwaningo zazikuluhlu lwe-0.05-0.1 N / m.Ukucacisa ngokuchanekileyo imilo kunye nobukhulu besicatshulwa, i-probe ibonakaliswe ngokweenkcukacha usebenzisa i-SEM.Kwikhiwane.Umzobo we-1a ubonisa isisombululo esiphezulu, ukunyusa okuphantsi ukuskena i-electron micrograph ye-PFQNM-LC-A-CAL probe, ebonelela ngombono opheleleyo woyilo lweprobe.Kwikhiwane.I-1b ibonisa imbonakalo eyandisiweyo yomphezulu wencam yeprobe, inika ulwazi malunga nokumila kunye nobukhulu bencam.Kwisiphelo esigqithiseleyo, inaliti yi-hemisphere malunga ne-140 nm ububanzi (Umfanekiso 1c).Ngezantsi oku, i-tip tapers ibe yi-conical shape, ifikelela kubude obulinganisiweyo malunga ne-500 nm.Ngaphandle kommandla we-tapering, incam yicylindrical kwaye iphela kubude bencam bubonke be-1.18 µm.Le yeyona nxalenye isebenzayo yengcebiso yeprobe.Ukongeza, i-polystyrene enkulu engqukuva (PS) probe (Novascan Technologies, Inc., Boone, Iowa, USA) enencam yobubanzi obuyi-45 µm kunye nespring constant ye-2 N/m nayo yasetyenziswa ukuvavanywa njenge-colloidal probe.ngePFQNM-LC-A-CAL 140 nm probe ukuthelekisa.
Kuye kwaxelwa ukuba ulwelo lunokubanjiswa phakathi kweprobe ye-AFM kunye nesakhiwo se-polymer brush ngexesha le-nanoindentation, eya kuthi isebenzise amandla aphezulu kwi-probe ye-AFM ngaphambi kokuba ichukumise umphezulu69.Le mpembelelo ye-viscous extrusion ngenxa yokugcinwa kwamanzi inokutshintsha indawo ebonakalayo yoqhagamshelwano, ngaloo ndlela ichaphazela imilinganiselo yemodyuli yomphezulu.Ukuphonononga isiphumo sejiyometri ye-probe kunye nesantya sokungeniswa ekugcinweni kolwelo, iigophe zamandla e-indentation ziye zacwangciswa kwiisampuli ze-lehfilcon A CL kusetyenziswa i-140 nm idayamitha yeprobe kumazinga okufuduswa rhoqo kwe-1 µm/s kunye ne-2 µm/s.probe idayamitha 45 µm, amandla azinzileyo useto 6 nN iphunyezwe nge-1 µm/s.Imifuniselo ene-probe eyi-140 nm ububanzi yenziwe ngesantya sokungeniswa kwe-1 µm/s kunye neseti yamandla angama-300 pN, ekhethwe ukudala uxinzelelo loqhagamshelwano ngaphakathi koluhlu lwefiziyoloji (1–8 kPa) lwenkophe ephezulu.uxinzelelo 72. Iisampulu ezithambileyo esele zenziwe nge-PAA hydrogel kunye noxinzelelo lwe-1 kPa zivavanyelwe amandla okufakelwa kwe-50 pN ngesantya se-1 μm / s usebenzisa i-probe enobubanzi be-140 nm.
Ekubeni ubude benxalenye ye-conical yencam ye-PFQNM-LC-A-CAL probe imalunga ne-500 nm, kuyo nayiphi na i-indentation deep <500 nm kunokucingelwa ngokukhuselekileyo ukuba ijometri ye-probe ngexesha lokungena iya kuhlala iyinyani kwi-indentation yayo. imilo yekhowuni.Ukongezelela, kucingelwa ukuba umphezulu wezinto eziphantsi kovavanyo uya kubonisa impendulo eguqukayo e-elastic, eya kuqinisekiswa kwakhona kula macandelo alandelayo.Ngoko ke, kuxhomekeke kwimilo kunye nobukhulu besicatshulwa, sakhetha imodeli ehambelana ne-cone-sphere eyaphuhliswa nguBriscoe, uSebastian kunye no-Adams, okhoyo kwisofthiwe yomthengisi, ukucubungula iimvavanyo zethu ze-AFM ze-nanoindentation (NanoScope).Isoftware yokuhlalutya idatha yokwahlula, iBruker) 73. Imodeli ichaza ubudlelwane bokufuduka ngamandla F (δ) kwikhowuni enesiphako se-apex.Kwikhiwane.Umzobo wesi-2 ubonisa ijometri yoqhagamshelwano ngexesha lokudityaniswa kwekhowuni eqinileyo enencam engqukuva, apho u-R yiradiyasi yencam engqukuva, a yiradiyasi yoqhagamshelwano, b yiradiyo yoqhagamshelwano ekupheleni kwencam yespherical, δ Irediyasi yoqhagamshelwano.ubunzulu bokujongwa, θ sisiqingatha se-engile yekhowuni.Umfanekiso we-SEM wale probe ubonisa ngokucacileyo ukuba i-140 nm yedayamitha ye-spherical incam idibana ngokuthe ngqo kwikhowuni, ngoko ke apha b uchazwa kuphela nge-R, okt b = R cos θ.Isoftware ebonelelwa ngumthengisi ibonelela ngobudlelwane be-cone-sphere ukubala amaxabiso emodyuli ye-Young's (E) ukusuka kwidatha yokwahlulwa kwamandla ngokuthatha i> b.Ubudlelwane:
apho u-F angamandla okungenisa, u-E yimodyuli kaLutsha, ν ngumlinganiselo wePoisson.Irediyasi yoqhagamshelwano a inokuqikelelwa kusetyenziswa:
Isicwangciso sejiyometri yoqhagamshelwano lwekowuni eqinileyo enencam engqukuva ecinezelwe kwimathiriyeli yeLefilcon yoqhagamshelwano lens enomaleko ongaphezulu weebhrashi zepolymer ezinamagatsha.
Ukuba u-≤ b, unxulumano lunciphisa kwi-equation kwi-indenter yesiqhelo engqukuva;
Sikholelwa ukuba unxibelelwano lweprobe yokujikela kunye nolwakhiwo lwebrashi yepolymer ye-PMPC kuya kubangela ukuba iradiyasi yoqhagamshelwano a ibe nkulu kune-spherical contact radius b.Ke ngoko, kuyo yonke imilinganiselo yobungakanani bemodyuli elastiki eyenziwe kolu phononongo, sisebenzise ukuxhomekeka okufunyenweyo kwimeko a > b.
Iimathiriyeli ze-ultrasoft zebhayomimetic ezifundwe kolu phononongo zazekeliswa ngokupheleleyo kusetyenziswa iscanning transmission electron microscopy (STEM) yecandelo lomnqamlezo wesampulu kunye ne-atomic force microscopy (AFM) yomphezulu.Olu phawu lomphezulu oluneenkcukacha lwenziwa njengokwandiswa komsebenzi wethu opapashwe ngaphambili, apho sinqume ukuba i-branchally branched polymeric brush structure ye-PMPC-modified lehfilcon A CL surface ibonise iimpawu ezifanayo zomatshini kwi-corneal tissue ye-14.Ngesi sizathu, sibhekisa kumphezulu welensi zoqhagamshelwano njengemathiriyeli ye-biomimetic14.Kwikhiwane.I-3a,b ibonisa amacandelo anqamlezayo we-branched PMPC polymer brush structures kumphezulu we-lehfilcon A CL substrate kunye ne-SiHy substrate engaphathwanga, ngokulandelelanayo.Imiphezulu yazo zombini iisampuli zahlaziywa ngakumbi kusetyenziswa imifanekiso ye-AFM ephezulu, eqinisekisa ngakumbi iziphumo zohlalutyo lwe-STEM (Umfanekiso 3c, d).Idityaniswe kunye, le mifanekiso inika ubude obuqikelelweyo be-PMPC branched polymer brush structure kwi-300-400 nm, ebaluleke kakhulu ekutolikeni imilinganiselo ye-AFM ye-nanoindentation.Olunye uqwalaselo oluphambili olusuka kwimifanekiso kukuba ulwakhiwo lomhlaba wonke lwe-CL biomimetic material luhluke ngokwe-morphologically ukusuka kwi-substrate ye-SiHy.Lo mahluko kwi-morphology yawo yomphezulu unokubonakala ngexesha lokusebenzisana kwabo ngoomatshini kunye ne-indenting AFM probe kwaye emva koko kumaxabiso alinganisiweyo emodyuli.
Imifanekiso ye-STEM enqamlezileyo (a) ye-lehfilcon A CL kunye (b) ne-SiHy substrate.Isikali bar, 500 nm.Imifanekiso ye-AFM yomphezulu we-lehfilcon A CL substrate (c) kunye nesiseko se-SiHy substrate (d) (3 µm × 3 µm).
Iipolymers zeBioinspired kunye nezakhiwo zebrashi yepolymer zithambile ngokwendalo kwaye zifundwe ngokubanzi kwaye zisetyenziswa kwizicelo ezahlukeneyo zebhayoloji74,75,76,77.Ngoko ke, kubalulekile ukusebenzisa indlela ye-AFM ye-nanoindentation, enokulinganisa ngokuchanekileyo nangokuthembekileyo iimpawu zabo zomatshini.Kodwa kwangaxeshanye, iipropathi ezizodwa zezi zixhobo ze-ultra-soft, ezifana ne-elastic modulus ephantsi kakhulu, umxholo wolwelo oluphezulu kunye ne-elasticity ephezulu, zihlala zenza kube nzima ukukhetha imathiriyeli efanelekileyo, imilo kunye nokumila kwe-indenting probe.ubukhulu.Oku kubalulekile ukuze i-indenter ingagqobhozi indawo ethambileyo yesampulu, nto leyo eya kukhokelela kwiimpazamo ekumiseleni indawo yokunxibelelana nomphezulu kunye nendawo yoqhakamshelwano.
Kule nto, ukuqonda okubanzi kwe-morphology ye-ultra-soft biomimetic materials (i-lehfilcon A CL) ibalulekile.Ulwazi malunga nobukhulu kunye nesakhiwo seebrashi ze-polymer zebranched ezifunyenwe ngokusebenzisa indlela yokucinga ibonelela ngesiseko sombonakaliso womatshini womphezulu usebenzisa iindlela ze-AFM ze-nanoindentation.Endaweni ye-micron-ubungakanani bespherical colloidal probes, sikhethe iPFQNM-LC-A-CAL silicon nitride probe (Bruker) enencam yobubanzi obuyi-140 nm, eyilelwe ngokukodwa ukwenza imaphu yobungakanani bepropathi yomatshini yeesampulu zebhayoloji 78, 79, 80 , 81, 82, 83, 84 Ingqiqo yokusebenzisa i-probes ebukhali xa kuthelekiswa ne-colloidal probes eqhelekileyo inokuchazwa ngeempawu zesakhiwo sezinto eziphathekayo.Ukuthelekisa ubungakanani bencam yeprobe (~ 140 nm) kunye neebrashi zepolymer zebranched kumphezulu weCL lehfilcon A, eboniswe kwiFig. 3a, kunokugqitywa ukuba incam inkulu ngokwaneleyo ukuba idibane ngqo nezi zakhiwo zebrashi, ezinokuthi zifikeleleke. kunciphisa ithuba lokugqobhoza incam kubo.Ukucacisa le ngongoma, kwi-Fig. 4 ngumfanekiso we-STEM we-lehfilcon A CL kunye ne-indenting tip ye-AFM probe (etsalwe kwisikali).
I-Schematic ebonisa umfanekiso we-STEM we-lehfilcon A CL kunye ne-ACM ye-indentation probe (etsalwa kwisikali).
Ukongeza, ubungakanani bencam ye-140 nm buncinci ngokwaneleyo ukuphepha umngcipheko wayo nayiphi na imiphumo ye-extrusion enamathelayo echazwe ngaphambili kwiibrashi ze-polymer eziveliswe yi-CP-AFM nanoindentation method69,71.Sicinga ukuba ngenxa yobume obukhethekileyo be-cone-spherical kunye nobukhulu obuncinci beli nqaku le-AFM (umzobo 1), ubume be-curve yamandla eveliswa yi-lehfilcon A CL nanoindentation ayiyi kuxhomekeka kwisantya sokungeniswa okanye ukulayisha / ukukhulula isantya. .Ngoko ke, ayichatshazelwa yimiphumo ye-poroelastic.Ukuvavanya le ngqikelelo, iisampulu ze-lehfilcon A CL zaye zafakwa kumandla angatshintshiyo aphezulu kusetyenziswa i-PFQNM-LC-A-CAL probe, kodwa ngesantya ezibini ezahlukeneyo, kunye nesiphumo sokuqina kunye nokurhoxa kwamandla okugobileyo kwasetyenziselwa ukucwangcisa amandla (nN) ngokwahlula (µm) ibonisiwe kuMfanekiso 5a.Kucacile ukuba amandla amagophe ngexesha lokulayishwa kunye nokukhulula zigqithisene ngokupheleleyo, kwaye akukho bungqina bucacileyo bokuba ukucheba okunyanzeliswayo kubunzulu be-zero kunyuka kunye nesantya sokufakela emfanekisweni, kubonisa ukuba izakhi zebrashi nganye zibonakaliswe ngaphandle kwesiphumo se-poroelastic.Ngokwahlukileyo, iziphumo zokugcinwa kwamanzi (i-viscous extrusion kunye ne-poroelasticity effects) ibonakala kwi-probe ye-45 µm ububanzi be-AFM kwisantya esifanayo sokungena kwaye igxininiswe yi-hysteresis phakathi kwe-stretch and retract curves, njengoko kuboniswe kuMfanekiso 5b.Ezi ziphumo zixhasa i-hypothesis kwaye zicebisa ukuba i-140 nm ye-diameter probes lukhetho olulungileyo lokubonisa umphezulu onjalo othambileyo.
i-lehfilcon A CL indentation force curves usebenzisa i-ACM;(a) usebenzisa iprobe enobubanzi obuyi-140 nm kumazinga amabini okulayisha, ebonisa ukungabikho kwempembelelo ye-poroelastic ngexesha lokuhlehla komphezulu;(b) usebenzisa iiprobe ezinobubanzi obuyi-45 µm kunye ne-140 nm.s ibonisa imiphumo ye-viscous extrusion kunye ne-poroelasticity yeeprobes ezinkulu xa kuthelekiswa neeprobes ezincinci.
Ukubonakalisa iindawo ze-ultrasoft, iindlela ze-AFM ze-nanoindentation kufuneka zibe neyona probe ingcono kakhulu yokufunda iipropati zezinto eziphantsi kwesifundo.Ukongeza kwi-tip shape kunye nobukhulu, uvakalelo lwe-AFM detector system, ukuvakalelwa kwi-tip deflection kwindawo yokuvavanya, kunye nokuqina kwe-cantilever kudlala indima ebalulekileyo ekunqumeni ukuchaneka kunye nokuthembeka kwe-nanoindentation.imilinganiselo.Kwinkqubo yethu ye-AFM, i-Position Sensitive Detector (PSD) umda wokufunyaniswa malunga ne-0.5 mV kwaye isekelwe kwinqanaba lentwasahlobo elilinganiswe kwangaphambili kunye novakalelo olubaliweyo lokuphambuka kolwelo lwe-PFQNM-LC-A-CAL probe, ehambelana Uvakalelo lomthwalo wethiyori.ingaphantsi kwe-0.1 pN.Ngoko ke, le ndlela ivumela ukulinganisa ubuncinci be-indentation force ≤ 0.1 pN ngaphandle kwenxalenye yengxolo ye-peripheral.Nangona kunjalo, akunakwenzeka ukuba inkqubo ye-AFM yokunciphisa ingxolo ye-peripheral ukuya kweli nqanaba ngenxa yezinto ezifana nokungcangcazela komatshini kunye ne-fluid dynamics.Ezi zinto zinciphisa uvakalelo olupheleleyo lwendlela ye-AFM ye-nanoindentation kwaye iphinda ibangele umqondiso wesandi sangasemva malunga ne-≤ 10 pN.Ukubonakaliswa komphezulu, iisampuli ze-lehfilcon A CL kunye ne-SiHy substrate zifakwe phantsi kweemeko ze-hydrated ngokupheleleyo zisebenzisa i-140 nm probe ye-SEM characterization, kwaye i-curves force curves yafakwa phakathi kwamandla (pN) kunye noxinzelelo.Iploti yokwahlula (µm) iboniswe kuMfanekiso 6a.Xa kuthelekiswa ne-substrate yesiseko se-SiHy, i-lehfilcon A CL force curve ibonisa ngokucacileyo isigaba senguqu eqala kwindawo yokudibanisa ne-polymer brashi ephothiweyo kunye nokuphela kokutshintsha okubukhali kwi-slope marking contact of the tip kunye nezinto eziphantsi.Le nxalenye yenguqu yegophe lamandla iqaqambisa ukuziphatha okunwebekayo okwenyani kwebrashi yepolymer yebranched kumphezulu, njengoko kungqinwa ligophe loxinzelelo ngokusondeleyo kwigophe loxinzelelo kunye nokwahluko kwiipropathi zoomatshini phakathi kwesakhiwo sebrashi kunye nezinto ezinkulu zeSiHy.Xa uthelekisa i-lefilcon.Ukwahlulwa komndilili wobude bebrashi yepolymer branched kumfanekiso we-STEM we-PCS (Umfanekiso 3a) kunye negophe layo lamandla ecaleni kwe-abscissa kwi-Fig. 3a.I-6a ibonisa ukuba indlela iyakwazi ukubona i-tip kunye ne-polymer branched ifikelela phezulu phezulu.Uqhagamshelwano phakathi kwezakhiwo zebrashi.Ukongeza, ukugqithelana ngokusondeleyo kweegophe zamandla kubonisa ukuba akukho siphumo sokugcina ulwelo.Kule meko, akukho kubambelela ngokupheleleyo phakathi kwenaliti kunye nomphezulu wesampuli.Amacandelo aphezulu kakhulu eengqungquthela zamandla kwiisampuli ezimbini zidibanisa, ezibonisa ukufana kweempawu zomatshini we-substrate materials.
(a) Iigophe ze-AFM ze-nanoindentation force ye-lehfilcon A CL substrates kunye ne-SiHy substrates, (b) ukunyanzeliswa kweegophe ezibonisa uqikelelo lwendawo yoqhagamshelwano kusetyenziswa indlela yengxolo yangasemva yongqameko.
Ukuze ufunde iinkcukacha ezicacileyo ze-curve yamandla, i-curve ye-tension ye-lehfilcon A CL isampula iphinda ifakwe kwi-Fig.Le grafu ibonelela ngolwazi olubalulekileyo malunga nengxolo yokuqala yangasemva.Ingxolo ikuluhlu lwe-±10 pN, olusetyenziselwa ukumisela ngokuchanekileyo indawo yoqhagamshelwano kunye nokubala ubunzulu bokungena.Njengoko kuchazwe kuncwadi, ukuchongwa kwamanqaku oqhagamshelwano kubalulekile ukuvavanya ngokuchanekileyo iimpawu zezinto eziphathekayo ezifana ne-modulus85.Indlela ebandakanya ukusetyenzwa okuzenzekelayo kwedatha yegophe lamandla ibonise ukufaneleka okuphuculweyo phakathi kokufaneleka kwedatha kunye nemilinganiselo yobungakanani bemathiriyeli ethambileyo86.Kulo msebenzi, ukhetho lwethu lwamanqaku oqhagamshelwano lulula kwaye lunenjongo, kodwa lunemida yalo.Indlela yethu egcinayo yokumisela indawo yoqhagamshelwano inokukhokelela kumaxabiso emodulus aqikelelwe kancinci kubunzulu obuncinci bokungeniswa (<100 nm).Ukusetyenziswa kwe-algorithm-based based touchpoint monitor kunye ne-automated data processing ingaba ukuqhubeka kwalo msebenzi kwixesha elizayo ukuqhubela phambili ukuphucula indlela yethu.Ngaloo ndlela, kwingxolo yangaphakathi yangaphakathi kumyalelo we-±10 pN, sichaza indawo yoqhagamshelwano njengendawo yokuqala yedatha kwi-x-axis kuMfanekiso 6b ngexabiso le-≥10 pN.Emva koko, ngokuhambelana nomda wengxolo we-10 pN, umgca othe nkqo kwinqanaba le-~0.27 µm uphawula indawo yokudibanisa nomphezulu, emva koko i-curve eyolula iqhubekile de i-substrate idibane nobunzulu bo- ~ 270 nm.Okubangel 'umdla kukuba, ngokusekwe kubungakanani bebrashi ye-polymer enee-branched (300-400 nm) ilinganiswe kusetyenziswa indlela yokucinga, ubunzulu be-indentation ye-CL lehfilcon Isampulu eqatshelweyo kusetyenziswa indlela yomqolo wengxolo yangasemva imalunga ne-270 nm, ekufutshane kakhulu ubungakanani bomlinganiselo nge-STEM.Ezi ziphumo ziqinisekisa ngakumbi ukuhambelana nokusebenziseka kobume kunye nobukhulu bencam ye-AFM yokuphonononga ukuhlohlwa kwesi sakhiwo sebhrashi yepolymer ethambileyo kakhulu kwaye enwenwe kakhulu.Le datha ikwabonelela ngobungqina obunamandla bokuxhasa indlela yethu yokusebenzisa ingxolo yangasemva njengondoqo wokukhomba iindawo zoqhagamshelwano.Ke ngoko, naziphi na iziphumo zobungakanani ezifunyenwe kwimodeli yezibalo kunye nokunyanzeliswa kwegophe kufuneka zichaneke.
Imilinganiselo yobungakanani beendlela ze-AFM ze-nanoindentation zixhomekeke ngokupheleleyo kwiimodeli zemathematika ezisetyenziselwa ukukhethwa kwedatha kunye nohlalutyo olulandelayo.Ngoko ke, kubalulekile ukuqwalasela zonke izinto ezinxulumene nokukhethwa kwe-indenter, iipropati eziphathekayo kunye noomatshini bokusebenzisana kwabo ngaphambi kokukhetha imodeli ethile.Kule meko, i-geometry ye-tip yayibonakaliswe ngononophelo usebenzisa i-SEM micrographs (umzobo 1), kwaye isekelwe kwiziphumo, i-140 nm ububanzi be-AFM i-nanoindenting probe kunye ne-cone enzima kunye ne-spherical tip geometry lukhetho oluhle lokubonisa i-lehfilcon A CL79 iisampulu. .Enye into ebalulekileyo ekufuneka ihlolwe ngononophelo kukuqina kwe-polymer material evavanywayo.Nangona idatha yokuqala ye-nanoindentation (iFig. 5a kunye ne-6a) ichaza ngokucacileyo iimpawu zokugqithwa kwe-tension kunye ne-compression curves, oko kukuthi, ukubuyiswa okupheleleyo kwe-elastiki yezinto eziphathekayo, kubaluleke kakhulu ukuqinisekisa ubume be-elastic abafowunelwa. .Ukuza kuthi ga ngoku, ukujongwa okubini okulandelelanayo kwenziwa kwindawo enye kumphezulu we-lehfilcon A CL isampuli kumyinge wokungeniswa kwe-1 µm/s phantsi kweemeko ezigcweleyo zokugalela amanzi.Isiphumo sedatha yegophe iboniswe kwifig.7 kwaye, njengoko kulindelekile, ukwanda kunye nokunyanzeliswa kweegophe zeeprinta ezimbini ziphantse zifane, ziqaqambisa ukuqina okuphezulu kwesakhiwo sebrashi yepolymer.
Iigophe zamandla amabini okufakwa kwindawo enye kumphezulu we-lehfilcon A CL zibonisa ukuqina okufanelekileyo komphezulu welensi.
Ngokusekelwe kulwazi olufunyenwe kwi-SEM kunye ne-STEM imifanekiso ye-probe tip kunye ne-lehfilcon A CL surface, ngokulandelanayo, imodeli ye-cone-sphere yimbonakaliso yeemathematika efanelekileyo yokusebenzisana phakathi kwe-AFM probe tip kunye ne-soft polymer material evavanywayo.Ukongeza, kule modeli ye-cone-sphere, uqikelelo olusisiseko malunga neepropathi ezinwebekayo zemathiriyeli eprintiweyo zibambe inyaniso kule mathiriyeli intsha ye-biomimetic kwaye zisetyenziselwa ukulinganisa imodyuli elastiki.
Emva kovavanyo olubanzi lwendlela ye-AFM ye-nanoindentation kunye namacandelo ayo, kubandakanywa iimpawu ze-indentation probe (imilo, ubukhulu, kunye nokuqina kwentwasahlobo), uvakalelo (ingxolo yangasemva kunye noqikelelo lwendawo yoqhagamshelwano), kunye neemodeli ezifanelekileyo zedatha (imilinganiselo yemodulus yobungakanani), indlela yayiyiyo. esetyenzisiweyo.bonisa iisampulu ezithambileyo ezifumaneka kurhwebo ukuqinisekisa iziphumo zobungakanani.I-polyacrylamide yorhwebo (PAAM) i-hydrogel ene-elastic modulus ye-1 kPa yavavanywa phantsi kweemeko ze-hydrated ngokusebenzisa i-140 nm probe.Iinkcukacha zovavanyo lwemodyuli nokubala zinikiwe kuLwazi oloNgezelelweyo.Iziphumo zabonisa ukuba i-avareji yemodyuli elinganisiweyo yi-0.92 kPa, kwaye i-%RSD kunye nepesenti (%) ukutenxa kwimodyuli eyaziwayo yayingaphantsi kwe-10%.Ezi ziphumo ziqinisekisa ukuchaneka kunye nokuphindaphinda kwendlela ye-AFM ye-nanoindentation esetyenziswe kulo msebenzi ukulinganisa i-moduli yezinto ze-ultrasoft.Imiphezulu yeesampulu ze-lehfilcon A CL kunye ne-SiHy base substrate zibonakaliswe ngakumbi ngokusebenzisa indlela efanayo ye-AFM ye-nanoindentation yokufunda imodyuli ebonakalayo ye-ultrasoft surface njengomsebenzi wobunzulu be-indentation.I-indentation force curves curves yenzelwe imizekelo emithathu yohlobo ngalunye (n = 3; i-indentation enye kwi-specimen) kumandla we-300 pN, isantya se-1 µm / s, kunye ne-hydration epheleleyo.Igophe lolwabelwano lwe-indentation force yaqikelelwa kusetyenziswa imodeli ye-cone-sphere.Ukufumana i-modulus exhomekeke kubunzulu be-indentation, i-40 nm inxalenye ebanzi ye-curve yamandla yamiselwa kwinqanaba ngalinye le-20 nm ukusuka kwindawo yoqhagamshelwano, kunye namaxabiso alinganisiweyo emodyuli kwinqanaba ngalinye le-curve yamandla.Spin Cy et al.Indlela efanayo isetyenziselwe ukubonakalisa i-modulus gradient ye-poly(lauryl methacrylate) (P12MA) iibhrashi zepolymer zisebenzisa i-colloidal AFM probe nanoindentation, kwaye ziyahambelana nedatha usebenzisa imodeli yoqhagamshelwano lweHertz.Le ndlela ibonelela ngeploti yemodyuli ecacileyo yoqhagamshelwano (kPa) ngokuchasene nobunzulu bokungena (nm), njengoko kubonisiwe kuMfanekiso 8, obonisa imodyuli ebonakalayo/ubunzulu bethambeka.I-modulus elastic edibeneyo ye-CL lehfilcon A isampuli ikwi-2-3 kPa ngaphakathi kwe-100 nm ephezulu yesampuli, ngaphaya kwayo iqala ukunyuka ngobunzulu.Ngakolunye uhlangothi, xa uvavanya i-substrate yesiseko se-SiHy ngaphandle kwefilimu efana ne-brush ebusweni, ubunzulu obuphezulu bokungeniswa obufunyenwe kumandla we-300 pN bungaphantsi kwe-50 nm, kwaye ixabiso lemodulus elifunyenwe kwidatha li malunga ne-400 kPa. , ethelekiseka kumaxabiso emodyuli eNtsha kwizinto ezininzi.
Imodyuli yoqhagamshelwano olubonakalayo (kPa) vs. ubunzulu bokungena (nm) kwi-lehfilcon A CL kunye ne-SiHy substrates esebenzisa indlela ye-AFM ye-nanoindentation kunye ne-cone-sphere geometry ukulinganisa imodyuli.
Owona mphezulu uphezulu wenoveli yebhayomimetic yebrashi yepolymer yebrashi yebrashi ibonisa imodyuli ephantsi kakhulu yokwaluka (2–3 kPa).Oku kuya kuhambelana nesiphelo esijingayo esikhululekileyo sebhrashi yepholima efojiweyo njengoko kubonisiwe kumfanekiso we-STEM.Nangona kukho ubungqina be-modulus gradient kumda wangaphandle we-CL, i-modulus substrate engundoqo ephezulu inempembelelo ngakumbi.Nangona kunjalo, i-100 nm ephezulu yomphezulu ingaphakathi kwe-20% yobude obupheleleyo bebrashi yepolymer edibeneyo, ngoko kunengqiqo ukucinga ukuba amaxabiso alinganisiweyo emodyuli kolu luhlu lobunzulu bobunzulu buchanekile kwaye abunamandla. kuxhomekeke kwisiphumo sento esezantsi.
Ngenxa yoyilo olulodwa lwe-biomimetic ye-lehfilcon A iilensi zoqhagamshelwano, ezibandakanya izakhiwo zebhrashi yepolymer ye-PMPC emiliselwe kumphezulu we-SiHy substrates, kunzima kakhulu ukuchaza ngokuthembekileyo iimpawu zomatshini wezakhiwo zabo zomphezulu usebenzisa iindlela zemveli zokulinganisa.Apha sibonisa indlela ephucukileyo ye-AFM ye-nanoindentation yokuchaza ngokuchanekileyo izinto ezithambileyo ezifana ne-lefilcon A enomxholo ophezulu wamanzi kunye nokuqina okuphezulu kakhulu.Le ndlela isekelwe ekusetyenzisweni kwe-AFM probe ubukhulu bayo bencam kunye nejometri zikhethwe ngononophelo ukuze zihambelane nemilinganiselo yesakhiwo se-ultra-soft surface features ukuba ishicilelwe.Le ndibaniselwano yemilinganiselo phakathi kweprobe kunye nolwakhiwo ibonelela ngovakalelo olwandisiweyo, okusivumela ukuba silinganise imodyuli ephantsi kunye neempawu zendalo ezilastiki zezinto zebrashi yepolymer, nokuba zithini na iziphumo ze-poroelastic.Iziphumo zabonisa ukuba iibhrashi zepolymer ze-PMPC ezikhethekileyo zebrashi zomphezulu welensi zinemodulus elastiki esezantsi kakhulu (ukuya kuthi ga kwi-2 kPa) kunye nokunwebeka okuphezulu kakhulu (malunga ne-100%) xa zivavanywa kwindawo enamanzi.Iziphumo ze-AFM nanoindentation nazo zisivumele ukuba sibonakalise imodyuli ebonakalayo yoqhagamshelwano / i-gradient enzulu (30 kPa / 200 nm) yendawo ye-lens ye-biomimetic.Le gradient inokuba ngenxa yomehluko wemodyuli phakathi kweebrashi zepolymer zebranched kunye ne-SiHy substrate, okanye i-branched structure / density ye-polymer brushes, okanye indibaniselwano yayo.Nangona kunjalo, uphando olunzulu olongezelelweyo luyafuneka ukuqonda ngokupheleleyo ubudlelwane phakathi kwesakhiwo kunye neepropati, ngakumbi umphumo we-brush branching kwiipropati zoomatshini.Imilinganiselo efanayo inokunceda ukubonakalisa iimpawu zemishini yobuso bezinye izinto ezithambileyo kunye nezixhobo zonyango.
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