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Kungekudala, i-platform ye-antimicrobial engenamichiza esekelwe kwi-nanotechnology esebenzisa i-nanostructures yamanzi eyenziweyo (EWNS) yenziwe.I-EWNS inomrhumo ophezulu ophezulu kwaye igcwele iintlobo ze-oksijini esebenzayo (ROS) enokuthi idibanise kwaye ingasebenzi inani le-microorganisms, kuquka i-pathogens yokutya.Apha kuboniswa ukuba iipropathi zabo ngexesha lokudibanisa zinokulungiswa kakuhle kwaye ziphuculwe ngakumbi ukunyusa amandla abo okulwa ne-antibacterial.Iqonga lebhubhoratri ye-EWNS yenzelwe ukulungisa kakuhle iipropati ze-EWNS ngokuguqula iiparamitha ze-synthesis.Iimpawu zeempawu ze-EWNS (intlawulo, ubukhulu kunye nomxholo we-ROS) usebenzisa iindlela zokuhlalutya zanamhlanje.Ukongeza, baye bavavanyelwa amandla abo okungasebenzi kwe-microbial ngokuchasene ne-microorganisms ezifumaneka kukutya ezifana ne-Escherichia coli, i-Salmonella enterica, i-Listeria innocuous, i-Mycobacterium paraaccidentum kunye ne-Saccharomyces cerevisiae.Iziphumo ezithiwe thaca apha zibonisa ukuba iipropathi ze-EWNS zinokulungiswa kakuhle ngexesha lokudityaniswa, okukhokelela ekwandeni okubonakalayo kokusebenza kakuhle kokungasebenzi kakuhle.Ngokukodwa, umrhumo we-surface wanda nge-factor of four kunye neentlobo ze-oksijini ezisebenzayo zanda.Izinga lokususa i-microbial lalixhomekeke kwi-microbially kwaye livela kwi-1.0 ukuya kwi-3.8 log emva kokutshatyalaliswa kwemizuzu ye-45 kwi-dose ye-aerosol ye-40,000 #/cc EWNS.
Ungcoliseko lweMicrobial ngoyena nobangela wokugula kokutya okubangelwa kukutya iintsholongwane okanye ityhefu yazo.EUnited States kuphela, izigulo ezibangelwa kukutya zibangela izigulo ezimalunga nezigidi ezingama-76, abantu abalaliswa esibhedlele abangama-325 000 baze bafe abangama-5 000 nyaka ngamnye.Ukongeza, iSebe lezoLimo laseMelika (i-USDA) liqikelela ukuba ukusetyenziswa okwandisiweyo kwemveliso entsha kunoxanduva lwe-48% yazo zonke izifo ezixeliweyo ezibangelwa kukutya e-United States2.Iindleko zezifo nokufa okubangelwa zizifo ezibangelwa kukutya eUnited States ziphezulu kakhulu, kuqikelelwa ngamaZiko oLawulo lweSifo kunye noThintelo (CDC) ngaphezu kwe-US $ 15.6 yezigidigidi ngonyaka3.
Okwangoku, ungenelelo lwekhemikhali4, i-radiation5 kunye ne-thermal6 ye-antimicrobial ukuqinisekisa ukhuseleko lokutya luqhutywa ikakhulu kwiindawo zolawulo olubalulekileyo (CCPs) ecaleni kwekhonkco lemveliso (ngokuqhelekileyo emva kokuvuna kunye/okanye ngexesha lokupakishwa) kunokuqhubekeka.ngoko ke, batyekele ekungcolisekeni.7. Ulawulo olungcono lokugula kokutya kunye nokonakala kokutya kufuna ungenelelo lwe-antimicrobial olunokuthi lusetyenziswe kwifama-to-table continuum ngelixa kuncitshiswa impembelelo yokusingqongileyo kunye neendleko.
Kungekudala, i-platform ye-antimicrobial esekelwe kwi-chemical-free, i-nanotechnology-based based that can inactivate surface and airborne bacteria usebenzisa i-nanostructures yamanzi (EWNS).I-EWNS yaqulunqwa ngokusebenzisa iinkqubo ezimbini ezihambelanayo, i-electrospray kunye ne-ionization yamanzi (Umfanekiso 1a).Izifundo zangaphambili zibonise ukuba i-EWNS ineseti ekhethekileyo yezinto eziphathekayo kunye ne-biological8,9,10.I-EWNS inomlinganiselo wee-electron ezili-10 kwisakhiwo ngasinye kunye nobukhulu be-nanoscale obuyi-25 nm (Fig. 1b,c)8,9,10.Ukongezelela, i-electron spin resonance (ESR) ibonise ukuba i-EWNS iqulethe inani elikhulu leentlobo ze-oxygen esebenzayo (ROS), ngokukodwa i-hydroxyl (OH•) kunye ne-superoxide (O2-) radicals (Fig. 1c)8.I-EVNS isemoyeni ixesha elide kwaye inokungqubana ne-microorganisms emisiwe emoyeni kwaye ikhoyo phezu komhlaba, ihambisa i-ROS yayo yokuhlawula imali kwaye ibangele ukungasebenzi kwe-microorganisms (Umfanekiso 1d).Olu phononongo lwakwangoko lubonise ukuba i-EWNS inokunxibelelana kunye kwaye ingasebenzi iibhaktheriya ezahlukeneyo zegram-negative kunye negram-positive, kubandakanya i-mycobacteria, kumphezulu kunye nomoya.Ukuhanjiswa kwe-electron microscopy kubonise ukuba ukungasebenzi kubangelwa ukuphazamiseka kwe-membrane yeseli.Ukongezelela, izifundo ze-acute inhalation zibonise ukuba amanani aphezulu e-EWNS awabangeli umonakalo wemiphunga okanye ukuvuvukala kwe8.
(a) I-Electrospray yenzeka xa kusetyenziswa amandla ombane aphezulu phakathi kwetyhubhu ye-capillary equlethe ulwelo kunye ne-electrode yokubala.(b) Ukusetyenziswa koxinzelelo oluphezulu kubangela izinto ezimbini ezahlukeneyo: (i) i-electrospraying yamanzi kunye (ii) nokwakheka kweentlobo ze-oksijini ezisebenzayo (ion) ezibanjwe kwi-EWNS.(c) Ulwakhiwo olulodwa lwe-EWNS.(d) Ngenxa yobume bayo be-nanoscale, i-EWNS ihamba kakhulu kwaye inokunxibelelana neentsholongwane ezihamba emoyeni.
Ukukwazi kweqonga le-antimicrobial ye-EWNS ukwenza i-microorganisms yokutya ingasebenzi kwindawo yokutya okutsha nayo ibonakalisiwe kutshanje.Kwakhona kuye kwaboniswa ukuba umrhumo womphezulu we-EWNS ngokudibanisa nentsimi yombane ingasetyenziselwa ukuphumeza ukuhanjiswa okujoliswe kuko.Ngaphezu koko, iziphumo zokuqala zeetamatato eziphilayo emva kokuvezwa kwemizuzu engama-90 kwi-EWNS malunga ne-50,000 #/cm3 yayikhuthaza, kunye neentlobo ezahlukeneyo ze-microorganisms zokutya ezifana ne-E. coli kunye ne-Listeria 11.Ukongeza, iimvavanyo zokuqala ze-organoleptic zibonise ukuba akukho ziphumo zoluvo xa kuthelekiswa nokulawula utamatisi.Nangona ezi ziphumo zokuqala zokungasebenzi zikhuthaza izicelo zokhuseleko lokutya nakumadosi e-EWNS aphantsi kakhulu angama-50,000#/cc.bona, kucacile ukuba amandla aphezulu okungasebenzi anokuba luncedo ngakumbi ekunciphiseni ngakumbi umngcipheko wosulelo kunye nokonakala.
Apha, siza kugxila kuphando lwethu kuphuhliso lweqonga lokuvelisa i-EWNS ukwenza ukulungiswa kakuhle kweeparamitha ze-synthesis kunye nokwenza ngcono iipropathi ze-physicochemical ze-EWNS ukunyusa amandla abo okulwa ne-antibacterial.Ngokukodwa, ukulungelelaniswa kugxininise ekwandiseni intlawulo yabo yomhlaba (ukuphucula ukuhanjiswa okujoliswe kuyo) kunye nomxholo we-ROS (ukuphucula ukusebenza kakuhle kokungasebenzi).Iimpawu eziphuculweyo ze-physico-chemical properties (ubungakanani, intlawulo kunye nomxholo we-ROS) usebenzisa iindlela zokuhlalutya zanamhlanje kunye nokusebenzisa ii-microorganisms zokutya eziqhelekileyo ezifana ne-E.
I-EVNS yenziwe nge-electrospraying ngaxeshanye kunye ne-ionization yamanzi ahlambulukileyo aphezulu (18 MΩ cm-1).I-nebulizer yombane i-12 isetyenziselwa i-atomization ye-liquids kunye ne-synthesis ye-polymer kunye ne-ceramic particles 13 kunye ne-fibers 14 yobukhulu obulawulwayo.
Njengoko kucacisiwe kupapasho lwangaphambili 8, 9, 10, 11, kuvavanyo oluqhelekileyo, umbane ophezulu wasetyenziswa phakathi kwecapillary yentsimbi kunye ne-grounded counter electrode.Ngethuba le nkqubo, iziganeko ezimbini ezihlukeneyo zenzeka: i) i-electrospray kunye nee) i-ionization yamanzi.Intsimi yombane eyomeleleyo phakathi kwee-electrode ezimbini ibangela ukuba iintlawulo ezingalunganga zakheke phezu kwamanzi ajiyileyo, okukhokelela ekuyilweni kweecones zeTaylor.Ngenxa yoko, amaconsi amanzi ahlawuliswa kakhulu ayenziwa, aqhubeka eqhekeka abe ngamancinci amancinci, njengakwithiyori yeRayleigh16.Ngelo xesha, amasimi ombane anamandla abangela ukuba ezinye iimolekyuli zamanzi zihlulwe kwaye zihluthe ii-electron (ionize), ezikhokelela ekubunjweni kweentlobo ezininzi ze-oxygen esebenzayo (ROS)17.I-ROS18 eyenziwe ngaxeshanye ifakwe kwi-EWNS (Fig. 1c).
Kwikhiwane.I-2a ibonisa inkqubo yokuvelisa i-EWNS ephuhliswe kwaye isetyenziswe kwi-EWNS synthesis kolu phononongo.Amanzi ahlambulukileyo agcinwe kwibhotile evaliweyo yondliwa nge-tube yeTeflon (2 mm ububanzi bangaphakathi) kwi-30G yenaliti yensimbi engenasici (i-metal capillary).Ukuhamba kwamanzi kulawulwa nguxinzelelo lomoya ngaphakathi kwebhotile, njengoko kuboniswe kuMfanekiso 2b.Inaliti ifakwe kwi-console yeTeflon kwaye inokulungiswa ngesandla kumgama othile ukusuka kwi-electrode counter.I-electrode yekhawuntari yidiski yealuminiyam ekhazimlisiweyo enomngxuma embindini wokuthatha iisampulu.Ngaphantsi kwe-electrode ye-counter yi-aluminium yesampulu ye-funnel, edityaniswe kuyo yonke isethingi yovavanyo ngokusebenzisa i-port yesampuli (Umfanekiso we-2b).Ukunqanda ukwakhiwa kwentlawulo enokuphazamisa ukusebenza kwesampulu, zonke iinxalenye zesampulu zisekelwe ngombane.
(a) INkqubo yobuNjineli yokuDala iNanostructure yaManzi (EWNS).(b) I-cross-section ye-sampler kunye ne-electrospray, ebonisa eyona parameters ibaluleke kakhulu.(c) Ukuseta umfuniselo wokungasebenzi kwebhaktiriya.
Inkqubo yokuvelisa i-EWNS echazwe ngasentla iyakwazi ukutshintsha iiparameters eziphambili zokusebenza ukuququzelela ukulungiswa kakuhle kweepropati ze-EWNS.Lungisa i-voltage esetyenzisiweyo (V), umgama phakathi kwenaliti kunye ne-electrode counter (L), kunye nokuhamba kwamanzi (φ) nge-capillary ukulungelelanisa iimpawu ze-EWNS.Uphawu olusetyenziselwa ukumela imidibaniso eyahlukeneyo: [V (kV), L (cm)].Lungisa ukuhamba kwamanzi ukuze ufumane i-Taylor cone ezinzileyo yesethi ethile [V, L].Ngenjongo yolu phononongo, i-diameter yokuvula i-counter electrode (D) igcinwe kwi-intshi ye-0.5 (1.29 cm).
Ngenxa yejometri encinci kunye ne-asymmetry, amandla ombane ombane akanakubalwa kwimigaqo yokuqala.Endaweni yoko, isoftware ye-QuickField™ (eSvendborg, eDenmark)19 yasetyenziswa ukubala indawo yombane.Intsimi yombane ayifani, ngoko ke ixabiso lendawo yombane kwinqanaba le-capillary lisetyenziswe njengexabiso lokubhekisela kwiindlela ezahlukeneyo.
Ngexesha lophononongo, udibaniso oluninzi lombane kunye nomgama phakathi kwenaliti kunye ne-electrode ye-counter yavavanywa ngokwemiqathango ye-Taylor cone formation, i-Taylor cone stability, i-EWNS yokuzinza kwemveliso, kunye nokuphindaphinda.Iindibaniso ezahlukeneyo zibonisiwe kwiTheyibhile eyoNgezelelweyo S1.
Imveliso yenkqubo yokuvelisa i-EWNS idibaniswe ngokuthe ngqo kwi-Scanning Mobility Particle Size Analyzer (SMPS, Model 3936, TSI, Shoreview, MN) yokulinganisa inani le-particle concentration, kunye ne-Aerosol Faraday Electrometer (TSI, Model 3068B, Shoreview, MN).) imisinga ye-aerosol yalinganiswa njengoko kuchaziwe kupapasho lwethu lwangaphambili.Zombini i-SMPS kunye ne-aerosol electrometer isampuli kwisantya sokuhamba kwe-0.5 L / min (iisampulu iyonke yokuhamba kwe-1 L / min).Inani lokugxininiswa kwamaqhekeza kunye nokuhamba kwe-aerosol kulinganiswe imizuzwana ye-120.Umlinganiselo uphindwa ngamaxesha angama-30.Ngokusekelwe kwimilinganiselo yangoku, intlawulo ye-aerosol iyonke ibalwa kwaye umyinge wentlawulo ye-EWNS uqikelelwa kwitotali yenani elinikiweyo lamasuntswana e-EWNS akhethiweyo.I-avareji yeendleko ze-EWNS ingabalwa kusetyenziswa i-Equation (1):
apho i-IEl ingumlinganiselo wangoku, i-NSMPS yingxingwa yedijithali elinganiswe nge-SMPS, kwaye i-φEl yizinga lokuhamba nge-electrometer nganye.
Ngenxa yokuba umswakama ohambelanayo (RH) uchaphazela intlawulo yomhlaba, iqondo lokushisa kunye (RH) zigcinwe zihlala zihlala ngexesha lovavanyo kwi-21 ° C kunye ne-45%, ngokulandelanayo.
I-Atomic force microscopy (AFM), i-Asylum MFP-3D (i-Asylum Research, i-Santa Barbara, i-CA) kunye ne-AC260T probe (i-Olympus, i-Tokyo, eJapan) zisetyenziselwa ukulinganisa ubungakanani kunye nobomi be-EWNS.I-AFM yokuskena i-frequency yayingu-1 Hz, indawo yokuskena yayiyi-5 μm × 5 μm, kunye nemigca ye-scan ye-256.Yonke imifanekiso yayiphantsi komyalelo we-1 wokulungelelaniswa komfanekiso usebenzisa i-Asylum software (i-mask range 100 nm, i-threshold 100 pm).
I-funnel yokuvavanya isusiwe kwaye i-mica surface ibekwe kumgama we-2.0 cm ukusuka kwi-electrode ye-counter kwi-avareji yexesha le-120 ukuphepha i-particle agglomeration kunye nokwakhiwa kwamaconsi angaqhelekanga kwi-mica surface.I-EWNS yatshizwa ngokuthe ngqo kumphezulu wemica esandula kusikwa (Ted Pella, Redding, CA).Umfanekiso womphezulu we-mica ngokukhawuleza emva kokutshiza kwe-AFM.I-engile yoqhagamshelwano yomphezulu we-mica esanda kusikwa engalungiswanga isondele ku-0°, ngoko ke i-EVNS isasazwa kumphezulu we-mica ngendlela yedome.Idayamitha (a) kunye nobude (h) bamathontsi asasazayo balinganiswa ngokuthe ngqo ukusuka kwi-AFM topography kwaye isetyenziselwa ukubala i-EWNS i-domed diffusion volume usebenzisa indlela yethu eqinisekisiweyo yangaphambili.Ukucinga ukuba i-EWNS ekwibhodi inomthamo ofanayo, idiameter elinganayo ingabalwa kusetyenziswa i-Equation (2):
Ngokusekelwe kwindlela yethu eyaphuhliswa ngaphambili, i-electron spin resonance (ESR) i-spin trap yayisetyenziselwa ukufumanisa ubukho bexesha elifutshane eliphakathi kwe-radical intermediates kwi-EWNS.I-aerosols yaxutywa nge-650 μm Midget sparger (i-Ace Glass, iVineland, NJ) equlethe isisombululo se-235 mM se-DEPMPO (5- (diethoxyphosphoryl) -5-methyl-1-pyrroline-N-oxide) (Oxis International Inc.).Portland, Oregon).Yonke imilinganiselo ye-ESR yenziwa ngokusebenzisa i-spectrometer ye-Bruker EMX (i-Bruker Instruments Inc. Billerica, MA, USA) kunye ne-flat panel cell.I-software ye-Acquisit (i-Bruker Instruments Inc. Billerica, MA, USA) yayisetyenziselwa ukuqokelela kunye nokuhlalutya idatha.Ukumiselwa kweempawu zeROS zenziwa kuphela kwisethi yeemeko zokusebenza [-6.5 kV, 4.0 cm].Ugxininiso lwe-EWNS lulinganiswa kusetyenziswa i-SMPS emva kokubalwa kwelahleko ye-EWNS kwimpembelelo.
Amanqanaba e-ozone abekwe esweni kusetyenziswa i-205 Dual Beam Ozone Monitor™ (2B Technologies, Boulder, Co)8,9,10.
Kuzo zonke iipropati ze-EWNS, ixabiso eliqhelekileyo lisetyenziswa njengexabiso lomlinganiselo, kwaye ukutenxa okusemgangathweni kusetyenziswa njengempazamo yokulinganisa.Uvavanyo lwe-T lwenziwa ukuthelekisa amaxabiso eempawu ze-EWNS eziphuculweyo kunye namaxabiso ahambelanayo esiseko se-EWNS.
Umfanekiso we-2c ubonisa inkqubo ye-electrostatic precipitation (EPES) ephuhliswe ngaphambili kunye nephawulwe “yokutsala” engasetyenziselwa ukuhanjiswa kwe-EWNS ekujoliswe kuyo kumphezulu.I-EPES isebenzisa iintlawulo ze-EVNS ezinokuthi "zikhokelwe" ngokuthe ngqo kwindawo ekujoliswe kuyo phantsi kwefuthe lentsimi yombane enamandla.Iinkcukacha zenkqubo ye-EPES zinikezelwe kupapasho lwakutsha nje nguPyrgiotakis et al.11 .Ngaloo ndlela, i-EPES iqulethe i-3D eprintiweyo ye-PVC yegumbi elineziphelo ezinqamlekileyo kwaye iqulethe intsimbi emibini ehambelanayo (i-304 insimbi engenasici, i-mirror coated) iipleyiti zetsimbi kwiziko le-15.24 cm ngaphandle.Iibhodi zixhunywe kumthombo wangaphandle we-voltage yangaphandle (i-Bertran 205B-10R, i-Spellman, i-Hauppauge, i-NY), i-plate ephantsi yayihlala ixhunywe kwi-voltage efanelekileyo, kwaye i-plate top yayihlala idibaniswa nomhlaba (umhlaba ojikelezayo).Iindonga zegumbi zigqunywe ngefoyile ye-aluminium, esekelwe ngombane ukuthintela ukulahleka kweesuntswana.Igumbi linocango oluvaliweyo lwangaphambili lokulayisha oluvumela umphezulu wovavanyo ukuba ubekwe kwizitendi zeplastiki eziziphakamisa ngaphezu kwepleyiti yentsimbi esezantsi ukunqanda ukuphazamiseka kwamandla ombane aphezulu.
Ukusebenza kakuhle kokubekwa kwe-EWNS kwi-EPES kubalwe ngokomgaqo ophuhliswe ngaphambili ochazwe kwi-Supplementary Figure S111.
Njengegumbi lokulawula, igumbi lesibini le-cylindrical flow flow lixhunywe kwi-series kwinkqubo ye-EPES, apho i-HEPA filter ephakathi yayisetyenziselwa ukususa i-EWNS.Njengoko kubonisiwe kuMfanekiso 2c, i-aerosol ye-EWNS yampontshwa kumagumbi amabini awakhelwe ngaphakathi.Isihluzi phakathi kwegumbi lolawulo kunye ne-EPES sisusa nayiphi na i-EWNS eseleyo ebangela ubushushu obufanayo (T), ukufuma okuhambelanayo (RH) kunye namanqanaba e-ozone.
Iimicroorganisms ezibalulekileyo zokutya zifunyenwe zingcolisa ukutya okutsha okufana ne-E. coli (ATCC #27325), isalathisi se-fecal, i-Salmonella enterica (ATCC #53647), i-pathogen yokutya, i-Listeria engenabungozi (ATCC #33090), i-surrogate ye-pathogenic Listeria monocytogenes, i-Mavisiamy ye-ATCC evela kwi-ATCC, i-Mavisinamies (ATCC #4098), endaweni yegwele lokubola, kunye nebhaktiriya enganyangekiyo engasebenziyo, iMycobacterium paralucky (ATCC #19686).
Thenga iibhokisi ezingacwangciswanga zeetumato zesidiliya kwimarike yasekhaya kwaye uzifake efrijini kwi-4°C de uyisebenzise (ukuya kutsho kwiintsuku ezi-3).Iitumato zokulinga zonke zazilingana, malunga ne-1/2 intshi ububanzi.
Inkcubeko, isitofu, ukuvezwa, kunye neeprothokholi zokubala zekholoni zichazwe kupapasho lwethu lwangaphambili kwaye zichazwe kwiDatha eyoNgezelelweyo.Ukusebenza kwe-EWNS kwavavanywa ngokubeka utamatisi ofakwe kwi-40,000 #/cm3 imizuzu engama-45.Ngokufutshane, iitumato ezintathu zazisetyenziselwa ukuvavanya i-microorganisms ephilayo ngexesha t = 0 min.Iitamatisi ezintathu zafakwa kwi-EPES kwaye zavezwa kwi-EWNS kwi-40,000 # / cc (i-EWNS evezwe utamatisi) kwaye ezintathu eziseleyo zafakwa kwigumbi lokulawula (iitamatisi zokulawula).Ukucutshungulwa okongeziweyo kweetamatato kumaqela omabini akuzange kwenziwe.I-EWNS-i-tomato evezwe kunye neetamatato zokulawula zisuswe emva kwemizuzu ye-45 ukuvavanya umphumo we-EWNS.
Uvavanyo ngalunye lwenziwa ngokuphindwe kathathu.Uhlalutyo lwedatha lwenziwa ngokweprotocol echazwe kwiDatha eyoNgezelelweyo.
Iindlela zokungasebenzi zihlolwe ngentlenga yeesampulu ze-EWNS eziveziweyo (imizuzu eyi-45 kwi-40,000 #/cm3 EWNS i-aerosol concentration) kunye neesampuli ezingenayo i-radiated ze-bacteria engenabungozi i-E. coli, i-Salmonella enterica kunye ne-Lactobacillus.Iinqununu zilungiswe kwi-2.5% ye-glutaraldehyde, i-1.25% ye-paraformaldehyde kunye ne-0.03% ye-picric acid kwi-0.1 M i-sodium cacodylate buffer (pH 7.4) kwiiyure ze-2 kwiqondo lokushisa.Emva kokuhlamba, lungisa i-post-fix kunye ne-1% ye-osmium tetroxide (OsO4) / 1.5% ye-potassium ferrocyanide (KFeCN6) kwiiyure ze-2, uhlambe amaxesha ama-3 emanzini kwaye udibanise kwi-1% ye-uranyl acetate ngeyure eli-1, uze uhlambe kabini emanzini, uze uchithe amanzi kwi-10%, i-9 imizuzu kwi-0% ye-0% ye-alcohol.Iisampuli zaye zafakwa kwi-propylene oxide kwiyure ye-1 kwaye zifakwe ngomxube we-1: 1 wepropylene oxide kunye ne-TAAP Epon (Marivac Canada Inc. St. Laurent, CA).Iisampuli zifakwe kwi-TAAB Epon kwaye zenziwe nge-polymerized kwi-60 ° C kwiiyure ze-48.I-resin ye-granular ephilisiwe yasikwa kwaye yabonwa yi-TEM usebenzisa i-electron microscopy microscope ye-JEOL 1200EX (JEOL, Tokyo, Japan) exhotyiswe ngekhamera ye-AMT 2k CCD (i-Advanced Microscopy Techniques, Corp., Woburn, Massachusetts, USA).
Zonke iimvavanyo zenziwe ngokuphindwe kathathu.Ngexesha ngalinye, ukuhlanjwa kwebhaktheriya kuye kwahlwayelwa ngokuphindwe kathathu, okubangele inani elipheleleyo lamanqaku edatha alithoba kwindawo nganye, umyinge owawusetyenziswa njengogxininiso lwebhaktiriya kuloo microorganism ethile.Ukutenxa okusemgangathweni kusetyenziswe njengempazamo yokulinganisa.Onke amanqaku abalwa.
I-logarithm yokuhla kwe-concentration yebhaktheriya xa kuthelekiswa ne-t = i-0 min ibalwe kusetyenziswa le fomula ilandelayo:
apho i-C0 yingqokelela yebhaktheriya kwisampulu yolawulo ngexesha le-0 (oko kukuthi emva kokuba umphezulu womile kodwa ngaphambi kokuba ubekwe kwigumbi) kunye ne-Cn kukuxinana kweebhaktheriya kumphezulu emva kwemizuzu ye-exposure.
Ukuqwalasela ukuthotywa kwemvelo kweebhaktheriya ngexesha lokuvezwa kwemizuzu ye-45, ukunciphisa ilogi xa kuthelekiswa nolawulo emva kwemizuzu ye-45 nayo ibalwe ngolu hlobo lulandelayo:
apho i-Cn i-concentration yebhaktheriya kwisampuli yokulawula ngexesha n kunye ne-Cn-Control yi-concentration ye-bacteria yokulawula ngexesha n.Idatha iboniswe njengokunciphisa ilogi xa kuthelekiswa nolawulo (akukho kubonakaliswa kwe-EWNS).
Ngexesha lokufunda, udibaniso oluninzi lombane kunye nomgama phakathi kwenaliti kunye ne-electrode ye-counter yavavanywa ngokwemiqathango ye-Taylor cone formation, i-Taylor cone stability, i-EWNS yokuzinza kwemveliso, kunye nokuphindaphinda.Iindibaniso ezahlukeneyo zibonisiwe kwiTheyibhile eyoNgezelelweyo S1.Iimeko ezimbini ezibonisa iipropati ezizinzileyo kunye nezinokuveliswa kwakhona (i-Taylor cone, isizukulwana se-EWNS, kunye nozinzo ngokuhamba kwexesha) zakhethwa ukuba kufundwe ngokubanzi.Kwikhiwane.Umzobo we-3 ubonisa iziphumo zentlawulo, ubungakanani, kunye nomxholo we-ROS kuzo zombini iimeko.Iziphumo zikwabonisiwe kwiThebhile 1. Ukwenza ireferensi, zombini iSazobe 3 kunye neTheyibhile 1 ibandakanya iipropathi ze-EWNS8, 9, 10, 11 (esisiseko-EWNS) eyazenziwe ngaphambili.Ubalo lokubaluleka kwamanani kusetyenziswa uvavanyo lwe-t olunemisila emibini lupapashwa kwakhona kwiTheyibhile eyoNgezelelweyo S2.Ukongezelela, idatha eyongezelelweyo ibandakanya izifundo zempembelelo ye-counter electrode isampula yesampulu ye-diameter (D) kunye nomgama phakathi kwe-electrode yomhlaba kunye ne-tip (L) (i-Supplementary Figures S2 kunye ne-S3).
(c) Ubungakanani bokuhanjiswa bulinganiswe yi-AFM.(df) Uphawu lwentlawulo engaphezulu.(g) Iimpawu ze-ROS ze-EPR.
Kwakhona kubalulekile ukuqaphela ukuba kuzo zonke iimeko ezingentla, umlinganiselo we-ionization wangoku wawuphakathi kwe-2 kunye ne-6 μA kunye ne-voltage phakathi kwe--3.8 kunye ne -6.5 kV, okubangelwa ukusetyenziswa kwamandla angaphantsi kwe-50 mW kule modyuli yoqhagamshelwano yesizukulwana esisodwa se-EWNS.Nangona i-EWNS yenziwa phantsi koxinzelelo oluphezulu, amanqanaba e-ozone ayephantsi kakhulu, awazange adlule kwi-60 ppb.
Umzobo owongezelelweyo S4 ubonisa iindawo zombane ezifanisiweyo ukwenzela [-6.5 kV, 4.0 cm] kunye ne [-3.8 kV, 0.5 cm] iimeko, ngokulandelanayo.Kwiimeko ze- [-6.5 kV, 4.0 cm] kunye ne- [-3.8 kV, 0.5 cm], izibalo zentsimi ziyi-2 × 105 V / m kunye ne-4.7 × 105 V / m, ngokulandelanayo.Oku kulindelekile, ekubeni kwimeko yesibini i-voltage-distance ratio iphezulu kakhulu.
Kwikhiwane.I-3a,b ibonisa i-EWNS idayamitha elinganiswa nge-AFM8.Umlinganiselo obaliweyo weediameter ze-EWNS bezingama-27 nm ne-19 nm kwizikim [-6.5 kV, 4.0 cm] kunye ne-[-3.8 kV, 0.5 cm] ngokulandelelanayo.Kwiimeko ze- [-6.5 kV, 4.0 cm] kunye ne- [-3.8 kV, 0.5 cm], ukutenxa komgangatho wejometri wonikezelo yi-1.41 kunye ne-1.45, ngokulandelanayo, ebonisa ukusabalalisa ubungakanani obumxinwa.Bobabini ubungakanani bentsingiselo kunye nokuphambuka komgangatho wejometri kusondele kakhulu kwisiseko se-EWNS, kwi-25 nm kunye ne-1.41, ngokulandelanayo.Kwikhiwane.I-3c ibonisa ukusabalalisa ubungakanani besiseko se-EWNS esilinganiswe ngokusebenzisa indlela efanayo phantsi kweemeko ezifanayo.
Kwikhiwane.3d,e ibonisa iziphumo zokuchazwa kwentlawulo.Idatha yimilinganiselo ye-avareji ye-30 yokulinganisa ngexesha elinye lokugxininiswa (#/cm3) kunye ne-current (I).Uhlalutyo lubonisa ukuba umyinge wentlawulo kwi-EWNS yi-22 ± 6 e- kunye ne-44 ± 6 e-ye- [-6.5 kV, 4.0 cm] kunye ne- [-3.8 kV, 0.5 cm], ngokulandelanayo.Zineentlawulo eziphezulu kakhulu zomphezulu xa kuthelekiswa ne-baseline EWNS (10 ± 2 e-), ngokuphindwe kabini ngaphezu kwemeko ye- [-6.5 kV, 4.0 cm] kunye namaxesha amane amakhulu kune [-3 .8 kV, 0.5 cm].Umzobo 3f ubonisa intlawulo.idatha yeBaseline-EWNS.
Ukusuka kwiimephu zoxinaniso zenombolo ye-EWNS (Amanani abongezelelweyo S5 kunye ne-S6), kunokubonwa ukuba imeko [-6.5 kV, 4.0 cm] inamasuntswana angaphezulu kakhulu [-3.8 kV, 0.5 cm].Kwakhona kuyafaneleka ukuba uqaphele ukuba ugxininiso lwenombolo ye-EWNS lubekwe esweni ukuya kwiiyure ze-4 (iFigure ezongezelelweyo ze-S5 kunye ne-S6), apho ukuzinza kwesizukulwana se-EWNS kubonise amanqanaba afanayo okugxininiswa kwenombolo ye-particle kwiimeko zombini.
Kwikhiwane.I-3g ibonisa i-spectrum ye-EPR emva kokuthabatha ulawulo lwe-EWNS oluphuculweyo (imvelaphi) kwi- [-6.5 kV, 4.0 cm].I-spectra ye-ROS nayo yathelekiswa ne-Baseline-EWNS scenario kumsebenzi opapashwe ngaphambili.Inani le-EWNS esabelayo nge-spin traps libalwe ukuba libe yi-7.5 × 104 EWNS / s, efana ne-Baseline-EWNS8 epapashwe ngaphambili.Imbonakalo ye-EPR ibonise ngokucacileyo ubukho beentlobo ezimbini ze-ROS, kunye ne-O2- iyeyona ntlobo iphambili kunye ne-OH• inganinzi kakhulu.Ukongeza, uthelekiso oluthe ngqo lokuqina kwencopho lubonise ukuba i-EWNS ephuculweyo inomxholo we-ROS ophezulu kakhulu xa kuthelekiswa nesiseko se-EWNS.
Kwikhiwane.I-4 ibonisa ukusebenza kakuhle kwe-EWNS kwi-EPES.Idatha iphinde ishwankathelwe kwiThebhile I kwaye ithelekiswa nedatha ye-EWNS yokuqala.Kuzo zombini iimeko ze-EUNS, i-deposition isondele kwi-100% nakwi-voltage ephantsi ye-3.0 kV.Ngokuqhelekileyo, i-3.0 kV yanele kwi-100% yokubekwa, kungakhathaliseki utshintsho lwentlawulo yomphezulu.Ngaphantsi kweemeko ezifanayo, ukusebenza kakuhle kwe-Baseline-EWNS kwaba yi-56% kuphela ngenxa yentlawulo yabo ephantsi (i-avareji ye-electron ye-10 nge-EWNS).
Kwikhiwane.5 kunye netafile.I-2 ishwankathela ixabiso lokungasebenzi kwee-microorganisms ezifakwe kumphezulu weetumato emva kokuvezwa malunga ne-40,000 #/cm3 EWNS imizuzu engama-45 kwimowudi efanelekileyo [-6.5 kV, 4.0 cm].Inoculated E. coli kunye neLactobacillus innocuous ibonise ukunciphisa okukhulu kweelogi ze-3.8 ngexesha lemizuzu ye-45.Ngaphantsi kweemeko ezifanayo, i-S. enterica yayine-2.2-log yehla, ngelixa i-S. cerevisiae kunye ne-M. parafortutum ine-1.0-log yehla.
I-electron micrographs (Umfanekiso we-6) ubonisa utshintsho lomzimba olubangelwa yi-EWNS kwi-Escherichia coli engenabungozi, i-Streptococcus, kunye neeseli zeLactobacillus ezikhokelela ekubeni zingasebenzi.Ibhaktheriya yokulawula yayineembrane zeeseli eziqinileyo, ngelixa ibhaktheriya evezwayo yonakalise i-membrane yangaphandle.
I-electron microscopic imaging yolawulo kunye neebhaktheriya eziveziweyo zibonise umonakalo we-membrane.
Idatha kwiipropathi ze-physicochemical ze-EWNS eziphuculweyo zibonisa ukuba iipropati (intlawulo ephezulu kunye nomxholo we-ROS) we-EWNS ziphuculwe kakhulu xa kuthelekiswa nedatha yesiseko ye-EWNS epapashwe ngaphambili8,9,10,11.Ngakolunye uhlangothi, ubukhulu babo buhlala kuluhlu lwe-nanometer, lufana kakhulu neziphumo ezichazwe ngaphambili, ezivumela ukuba bahlale emoyeni ixesha elide.I-polydispersity eqatshelweyo inokuchazwa ngotshintsho lwentlawulo yomphezulu obonisa ubungakanani be-EWNS, ukungahambi kakuhle kwe-Rayleigh effect, kunye nokubambisana okunokwenzeka.Nangona kunjalo, njengoko kucacisiwe nguNielsen et al.I-22, intlawulo ephezulu yomphezulu inciphisa ukuguquka kwamanzi ngokwandisa ngokufanelekileyo amandla angaphezulu / uxinzelelo lokuhla kwamanzi.Kupapasho lwethu lwangaphambili8 le nkcazo-bungcali yaqinisekiswa ngokuvavanywa kwi-microdroplets 22 kunye ne-EWNS.Ilahleko yentlawulo ngexesha elongezelelekileyo nako kunokuchaphazela ubungakanani kwaye kube negalelo kulwabiwo lobungakanani obuqatshelweyo.