Tinokutendai nekushanyira Nature.com. Shanduro yebrowser yauri kushandisa ine rutsigiro rushoma rweCSS. Kuti uwane ruzivo rwakanaka, tinokurudzira kuti ushandise browser yakagadziridzwa (kana kuti udzime Compatibility Mode muInternet Explorer). Panguva ino, kuti tive nechokwadi chekuti rutsigiro runoramba ruchienderera mberi, tichaisa saiti iyi isina masitayera uye JavaScript.
Munguva pfupi yapfuura, puratifomu isina mishonga inorwisa utachiona yakavakirwa pa nanotechnology inoshandisa nanostructures dzemvura dzekugadzira (EWNS) yakagadzirwa. EWNS ine simba guru pamusoro uye yakazara ne reactive oxygen species (ROS) inogona kusangana nekumisa tupukanana twakawanda, kusanganisira tupukanana tunobva muchikafu. Pano zvinoratidzwa kuti hunhu hwayo panguva yekugadzira hunogona kugadziriswa zvakanaka uye kugadziriswa kuti iwedzere simba rayo rekurwisa tupukanana. Puratifomu yerabhoritari yeEWNS yakagadzirwa kuti igadzirise hunhu hweEWNS nekushandura maparamita ekugadzira. Kutsanangurwa kwehunhu hweEWNS (charge, saizi uye zviri mukati meROS) uchishandisa nzira dzemazuva ano dzekuongorora. Pamusoro pezvo, dzakaongororwa kuti dzione kugona kwadzo kwekudzivirira tupukanana tunobva muchikafu twakadai seEscherichia coli, Salmonella enterica, Listeria innocuous, Mycobacterium paraaccidentum uye Saccharomyces cerevisiae. Mhedzisiro yakapihwa pano inoratidza kuti hunhu hweEWNS hunogona kugadziriswa zvakanaka panguva yekugadzira, zvichikonzera kuwedzera kukuru mukushanda kweinactivation. Kunyanya, simba repamusoro rakawedzera nechina uye mhando dze reactive oxygen dzakawedzera. Kubviswa kwehutachiona kwaienderana nehutachiona uye kwaibva pa1.0 kusvika 3.8 log mushure mekunwa mushonga we40,000 #/cc EWNS kwemaminitsi makumi mana nemashanu.
Kusvibiswa kwehutachiona ndiko kunonyanya kukonzera zvirwere zvinokonzerwa nekudya zvinokonzerwa nekunwa utachiona kana chepfu yahwo. MuUnited States chete, zvirwere zvinokonzerwa nekudya zvinokonzera zvirwere zvinosvika mamiriyoni makumi manomwe nematanhatu, vanhu vanopinda muchipatara vanosvika zviuru mazana matatu nemakumi maviri nemashanu, uye vanhu zviuru zvishanu vanofa gore rega rega1. Pamusoro pezvo, Dhipatimendi rezvekurima reUnited States (USDA) rinofungidzira kuti kuwedzerwa kwekudya kwezvirimwa zvitsva ndiko kunokonzera 48% yezvirwere zvese zvinozivikanwa zvinokonzerwa nekudya muUnited States2. Mutengo wezvirwere nerufu zvinokonzerwa nehutachiona hunokonzerwa nekudya muUnited States wakakwira zvikuru, unofungidzirwa neCenters for Disease Control and Prevention (CDC) kuti upfuure US$15.6 bhiriyoni pagore3.
Parizvino, mishonga inorwisa utachiona yemakemikari4, radiation5 uye thermal6 kuitira kuona kuti chikafu chakachengeteka inonyanya kuitwa panzvimbo dzakaganhurirwa dzekudzora (CCPs) pamwe chete nekugadzirwa (kazhinji mushure mekukohwa uye/kana panguva yekurongedza) pane kugara ichishandiswa. Saka, inogona kusvibiswa zvakanyanya. 7. Kudzora zviri nani zvirwere zvinokonzerwa nechikafu uye kuora kwechikafu kunoda mishonga inorwisa utachiona inogona kushandiswa munzvimbo dzese dzekurima uku ichideredza kukanganisa kwezvakatipoteredza nemitengo.
Munguva pfupi yapfuura, puratifomu isina makemikari, ine nanotechnology-based antimicrobial yakagadzirwa inogona kumisa mabhakitiriya epamusoro neanobhururuka achishandisa nanostructures dzemvura dzekugadzira (EWNS). EWNS yakagadzirwa uchishandisa maitiro maviri akafanana, electrospray uye water ionization (Mufananidzo 1a). Zvidzidzo zvekare zvakaratidza kuti EWNS ine seti yakasiyana yehunhu hwepanyama nehwepamuviri8,9,10. EWNS ine avhareji yemaerekitironi gumi pachivakwa chimwe nechimwe uye avhareji yehukuru hwenanoscale ye25 nm (Mufananidzo 1b,c)8,9,10. Pamusoro pezvo, electron spin resonance (ESR) yakaratidza kuti EWNS ine huwandu hwakawanda hwe reactive oxygen species (ROS), kunyanya hydroxyl (OH•) uye superoxide (O2-) radicals (Mufananidzo 1c)8. EVNS iri mumhepo kwenguva yakareba uye inogona kurovera ne microorganisms dzakamiswa mumhepo uye dziripo pamusoro, dzichipa ROS payload yavo uye zvichikonzera kusashanda kwe microorganisms (Mufananidzo 1d). Zvidzidzo izvi zvepakutanga zvakaratidzawo kuti EWNS inogona kusangana nehutachiona hwakasiyana-siyana hwe gram-negative ne gram-positive, kusanganisira mycobacteria, pamusoro nepamhepo. Kuongororwa kwema electron microscopy kwakaratidza kuti kusagadzikana kwacho kwakakonzerwa nekukanganiswa kwe membrane yesero. Pamusoro pezvo, zvidzidzo zvekufema zvakaratidza kuti huwandu hwakawanda hweEWNS hahukonzeri kukuvara kwemapapu kana kuzvimba 8.
(a) Kupfapfaidza kwemagetsi kunoitika kana simba remagetsi rakakwira rakaiswa pakati pechubhu ye capillary ine mvura uye counter electrode. (b) Kushandiswa kwekumanikidzwa kwakanyanya kunoguma nezviitiko zviviri zvakasiyana: (i) kupfapfaidza kwemvura nemagetsi uye (ii) kuumbwa kwemhando dzeokisijeni dzinoshanda (ions) dzakabatwa muEWNS. (c) Maumbirwo akasiyana eEWNS. (d) Nekuda kwehunhu hwadzo hwe nanoscale, EWNS dzinofamba zvakanyanya uye dzinogona kusangana nezvirwere zvinotapukira zviri mumhepo.
Kugona kwepuratifomu yeEWNS inorwisa utachiona kudzima tupukanana tunobva muchikafu pamusoro pechikafu chitsva kwakaratidzwawo munguva pfupi yapfuura. Zvakaratidzwawo kuti simba repamusoro reEWNS pamwe chete nesimba remagetsi rinogona kushandiswa kusvika pakuendeswa kwakatarwa. Uyezve, mhedzisiro yekutanga yematomatisi eorganic mushure mekusangana neEWNS kwemaminitsi makumi mapfumbamwe pa50,000 #/cm3 yaikurudzira, netupukanana twakasiyana-siyana tunobva muchikafu senge E. coli naListeria 11 twakaonekwa. Pamusoro pezvo, bvunzo dzekutanga dze organoleptic hadzina kuratidza mhedzisiro yekunzwa kana tichienzanisa nematomatisi ekudzora. Kunyangwe mhedzisiro iyi yekutanga yekudzima ichikurudzira kushandiswa kwechikafu kunyangwe pamadhora mashoma eEWNS e50,000#/cc. ona, zviri pachena kuti mukana wepamusoro wekudzima ungave wakanakira kuderedza njodzi yehutachiona nekuora.
Pano, tichatarisa tsvakiridzo yedu pakugadzira chikuva chekugadzira EWNS kuti tigone kugadzirisa zvakanaka maparamita ekugadzira uye kugadzirisa hunhu hwefizikisi yeEWNS kuti iwedzere kugona kwayo kurwisa mabhakitiriya. Kunyanya, kugadzirisa kwakatarisana nekuwedzera simba rayo repamusoro (kuvandudza kuendeswa kwakatarwa) uye huwandu hweROS (kuvandudza kushanda zvakanaka kwekusashanda). Rondedzera hunhu hwefizikisi-kemikari hwakagadziriswa (hukuru, simba uye huwandu hweROS) uchishandisa nzira dzemazuva ano dzekuongorora uye shandisa tupukanana twakajairika twechikafu senge E. .
EVNS yakagadzirwa nekupfapfaidza nemagetsi panguva imwe chete uye ionization yemvura yakachena (18 MΩ cm–1). Nebulizer yemagetsi 12 inowanzo shandiswa pakugadzira atomization yezvinwiwa uye kugadzira polymer neceramic particles 13 uye fibers 14 dzehukuru hwakadzorwa.
Sezvakatsanangurwa muzvinyorwa zvekare 8, 9, 10, 11, mukuyedza kwakajairika, voltage yakakwira yakashandiswa pakati pesimbi capillary ne grounded counter electrode. Munguva iyi, zviitiko zviviri zvakasiyana zvinoitika: i) electrospray uye ii) water ionization. Simba remagetsi rakasimba pakati pema electrodes maviri rinoita kuti negative charges iungane pamusoro pemvura yakakomberedzwa, zvichikonzera kuumbwa kwemaTaylor cones. Nekuda kweizvozvo, madonhwe emvura ane chaji yakawanda anoumbwa, ayo anoramba achipatsanuka kuita zvidimbu zvidiki, sezviri muRayleigh theory16. Panguva imwe chete, minda yemagetsi yakasimba inoita kuti mamwe mamorekuru emvura apatsanuke uye abvise maerekitironi (ionize), izvo zvinotungamira pakuumbwa kwehuwandu hwakawanda hwe reactive oxygen species (ROS)17. ROS18 yakagadzirwa panguva imwe chete yakavharirwa muEWNS (Mufananidzo 1c).
Pamufananidzo 2a panoratidza sisitimu yekugadzira EWNS yakagadzirwa uye yakashandiswa mukugadzirwa kweEWNS muchidzidzo ichi. Mvura yakachena yakachengetwa mubhodhoro rakavharwa yakapinzwa kuburikidza nechubhu yeTeflon (dhayamita yemukati ye2 mm) mutsono yesimbi isina ngura ye30G (capillary yesimbi). Kuyerera kwemvura kunodzorwa nekumanikidzwa kwemhepo mukati mebhodhoro, sezvakaratidzwa paMufananidzo 2b. Tsono yacho yakaiswa paTeflon console uye inogona kugadziriswa nemaoko kusvika kure kubva paelectrode yecounter. Electrode yecounter idhisiki realuminium rakaporishwa rine gomba pakati pekutora sampling. Pasi peelectrode yecounter pane funnel yealuminium sampling, iyo yakabatana kune zvimwe zvese zvekugadzirisa kuburikidza nechiteshi chesampling (Mufananidzo 2b). Kuti kudzivirira kuunganidza chaji kunogona kukanganisa mashandiro esampler, zvikamu zvese zvesampler zvinoiswa pasi pemagetsi.
(a) Sisitimu yekugadzira mvura ine mainjiniya (EWNS). (b) Chikamu chemuchina wekuongorora sampler neelectrospray, zvichiratidza zvinhu zvakakosha. (c) Kugadzirira kwekuyedza kwekusashanda kwebhakitiriya.
Sisitimu yekugadzira EWNS yakatsanangurwa pamusoro apa inokwanisa kuchinja ma parameter ekushanda akakosha kuti zvive nyore kugadzirisa zvakanaka hunhu hweEWNS. Gadzirisa voltage inoshandiswa (V), daro riri pakati petsono ne counter electrode (L), uye kuyerera kwemvura (φ) kuburikidza ne capillary kuti igadzirise hunhu hweEWNS. Chiratidzo chinoshandiswa kumiririra misanganiswa yakasiyana: [V (kV), L (cm)]. Gadzirisa kuyerera kwemvura kuti uwane Taylor cone yakagadzikana yeimwe seti [V, L]. Pachinangwa chechidzidzo ichi, dhayamita yekuvhura kwe counter electrode (D) yakachengetwa pa 0.5 inches (1.29 cm).
Nekuda kwe geometry shoma uye kusaenzana, simba remagetsi harigone kuverengerwa kubva pamisimboti yekutanga. Pane kudaro, software yeQuickField™ (Svendborg, Denmark)19 yakashandiswa kuverenga magetsi. Magetsi haana kufanana, saka kukosha kwemagetsi ari pamucheto we capillary kwakashandiswa sereferensi yemaitiro akasiyana-siyana.
Munguva yekudzidza, kusanganiswa kwakawanda kwemagetsi uye daro riri pakati petsono ne counter electrode kwakaongororwa maererano nekuumbwa kweTaylor cone, kugadzikana kweTaylor cone, kugadzikana kwekugadzirwa kweEWNS, uye kugona kudzokororwa. Kusanganiswa kwakasiyana-siyana kunoratidzwa muSupplementary Table S1.
Kubuda kwehurongwa hwekugadzira EWNS kwakabatana zvakananga neScanning Mobility Particle Size Analyzer (SMPS, Model 3936, TSI, Shoreview, MN) yekuyera huwandu hwe particle number, pamwe neAerosol Faraday Electrometer (TSI, Model 3068B, Shoreview, MN). ) ye aerosol currents yakayerwa sezvakatsanangurwa mubhuku redu rapfuura. SMPS ne aerosol electrometer zvakayerwa pa flow rate ye 0.5 L/min (total sample flow 1 L/min). Nhamba ye particles uye aerosol flow yakayerwa kwemasekonzi zana nemakumi maviri. Kuyerwa kunodzokororwa ka30. Zvichibva pa current measurements, total aerosol charge inoverengerwa uye avhareji ye EWNS charge inofungidzirwa yehuwandu hwe EWNS particles dzakasarudzwa. Avhareji yemutengo we EWNS inogona kuverengerwa uchishandisa Equation (1):
apo IEl ndiyo current yakayerwa, NSMPS ndiyo digital concentration yakayerwa neSMPS, uye φEl ndiyo flow rate pa electrometer.
Nekuti hunyoro (RH) hunokanganisa simba repamusoro, tembiricha uye (RH) zvakachengetwa zvakafanana panguva yekuyedza pa21°C uye 45%, zvichiteerana.
Michina yeAtomic force microscopy (AFM), Asylum MFP-3D (Asylum Research, Santa Barbara, CA) uye AC260T probe (Olympus, Tokyo, Japan) zvakashandiswa kuyera saizi uye hupenyu hweEWNS. Kuongororwa kweAFM kwaive 1 Hz, nzvimbo yekuongororwa yaive 5 μm × 5 μm, uye mitsara yekuongororwa 256. Mifananidzo yese yakaongororwa uchishandisa software yeAsylum (mask range 100 nm, threshold 100 pm).
Funnel yekuyedza yakabviswa uye pamusoro pemica pakaiswa chinhambwe che 2.0 cm kubva pa counter electrode kwenguva yeavhareji ye 120 s kudzivirira kuungana kwezvikamu uye kuumbwa kwemadonhwe asina kurongeka pamusoro pemica. EWNS yakapfapfaidzwa zvakananga pamusoro pemica ichangobva kuchekwa (Ted Pella, Redding, CA). Mufananidzo wepamusoro pemica mushure mekunge AFM yadonha. Kona yekubatana pamusoro pemica ichangobva kuchekwa isina kugadziriswa iri pedyo ne 0°, saka EVNS inoparadzirwa pamusoro pemica muchimiro che dome. Dhayamita (a) nekukwirira (h) kwemadonhwe anopararira zvakayerwa zvakananga kubva kuAFM topography uye zvakashandiswa kuverenga vhoriyamu yeEWNS domed diffusion uchishandisa nzira yedu yatakambo simbisa. Tichifunga kuti EWNS iri mubhodhi ine vhoriyamu yakafanana, dhayamita yakaenzana inogona kuverengerwa uchishandisa Equation (2):
Zvichibva panzira yedu yatakashandisa kare, electron spin resonance (ESR) spin trap yakashandiswa kuona kuvapo kweradical intermediates yenguva pfupi muEWNS. MaAerosols akaburitswa kuburikidza ne650 μm Midget sparger (Ace Glass, Vineland, NJ) ine 235 mM solution yeDEPMPO(5-(diethoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide) (Oxis International Inc.). Portland, Oregon). Kuyerwa kwese kweESR kwakaitwa uchishandisa Bruker EMX spectrometer (Bruker Instruments Inc. Billerica, MA, USA) uye flat panel cell. Acquisit software (Bruker Instruments Inc. Billerica, MA, USA) yakashandiswa kuunganidza nekuongorora data. Kuongororwa kwehunhu hweROS kwakaitwa chete kune seti yemamiriro ekushanda [-6.5 kV, 4.0 cm]. Kuwanda kweEWNS kwakayerwa uchishandisa SMPS mushure mekuverenga kurasikirwa kweEWNS mu impactor.
Mazinga eOzone akaongororwa uchishandisa 205 Dual Beam Ozone Monitor™ (2B Technologies, Boulder, Co)8,9,10.
Pazvinhu zvese zveEWNS, avhareji ndiyo inoshandiswa sechiyero chekuyera, uye standard deviation ndiyo inoshandiswa sechikanganiso chekuyera. T-tests dzakaitwa kuenzanisa kukosha kweEWNS attributes dzakagadziriswa nemitengo inoenderana nebase EWNS.
Mufananidzo 2c unoratidza sisitimu ye "kudhonza" yakagadzirwa kare uye yakasarudzika inogona kushandiswa pakuunza EWNS pamusoro. EPES inoshandisa machaji eEVNS anogona "kutungamirirwa" zvakananga pamusoro pechinangwa pasi pekupesvedzwa nesimba remagetsi rakasimba. Ruzivo rwesisitimu yeEPES rwunoratidzwa muchinyorwa chazvino chaPyrgiotakis et al. 11. Saka, EPES ine kamuri rePVC rakadhindwa re3D rine magumo akatetepa uye rine maplate maviri esimbi akafanana (304 stainless steel, mirror coated) ari pakati pe15.24 cm. Mabhodhi akabatanidzwa kune sosi yekunze ine voltage yakakwira (Bertran 205B-10R, Spellman, Hauppauge, NY), ndiro yepasi yaigara yakabatana nevoltage yakanaka, uye ndiro yepamusoro yaigara yakabatana nepasi (pasi rinoyangarara). Madziro ekamuri akafukidzwa nealuminium foil, iyo yakagadzikwa nemagetsi kudzivirira kurasikirwa kwezvikamu. Kamuri iri rine gonhi rekumberi rakavharirwa rinobvumira nzvimbo dzekuyedza kuti dziiswe pamapurasitiki anodzisimudza pamusoro pesimbi yepasi kudzivirira kukanganiswa kwemagetsi akawanda.
Kushanda zvakanaka kweEWNS muEPES kwakaverengerwa zvichienderana neprotocol yakagadzirwa kare yakatsanangurwa muSupplementary Figure S111.
Sekamuri yekudzora, imba yechipiri yekuyerera yakaita sedenderedzwa yakabatana nehurongwa hweEPES, umo firita yepakati yeHEPA yakashandiswa kubvisa EWNS. Sezvakaratidzwa muMufananidzo 2c, aerosol yeEWNS yakapombwa nemakamuri maviri akavakirwa mukati. Sefa iri pakati pekamuri yekudzora neEPES inobvisa chero EWNS yasara zvichikonzera tembiricha yakafanana (T), hunyoro (RH) uye ozone levels.
Mabhakitiriya akakosha anowanikwa muchikafu akawanikwa achisvibisa chikafu chitsva chakadai seE. coli (ATCC #27325), fecal indicator, Salmonella enterica (ATCC #53647), foodborne pathogen, Listeria isina njodzi (ATCC #33090), inotsiva Listeria monocytogenes inouraya utachiona, inobva kuATCC (Manassas, VA) Saccharomyces cerevisiae (ATCC #4098), inotsiva mbiriso inoora, uye bhakitiriya risingashande rinorwisa utachiona, Mycobacterium paralucky (ATCC #19686).
Tenga mabhokisi ematomatisi emazambiringa asina kugadzirwa kubva kumusika wemuno moaisa mufiriji pa4°C kusvika ashandiswa (kusvika mazuva matatu). Matomatisi ekuyedza ese aive akaenzana, dhayamita yawo inenge 1/2 inch.
Maitiro ekurima, kubaya, kusangana, uye huwandu hwemakoloni zvakatsanangurwa muchinyorwa chedu chekare uye zvakatsanangurwa muSupplementary Data. Kushanda kweEWNS kwakaongororwa nekuisa madomasi akapinzwa muchikamu che40,000 #/cm3 kwemaminitsi makumi mana nemashanu. Muchidimbu, madomasi matatu akashandiswa kuongorora tupukanana twakasara panguva t = 0 min. Madomasi matatu akaiswa muEPES ndokuiswa muchikamu cheEWNS pa40,000 #/cc (madomasi akapinzwa muEWNS) uye mamwe matatu akasara akaiswa mukamuri rekudzora (madomasi ekudzora). Kugadziriswa kwemamwe madomasi mumapoka ese maviri hakuna kuitwa. Madomasi akapinzwa muchikamu cheEWNS nematomasi ekudzora akabviswa mushure memaminitsi makumi mana nemashanu kuti aongorore kushanda kweEWNS.
Kuedza kwega kwega kwakaitwa katatu. Kuongororwa kwedata kwakaitwa zvichienderana neprotocol yakatsanangurwa muSupplementary Data.
Maitiro ekusashanda akaongororwa nekuisa mvura mumasampuli eEWNS akafumurwa (45 min pa 40,000 #/cm3 EWNS aerosol concentration) uye masampuli asina kupiswa emabhakitiriya asina njodzi E. coli, Salmonella enterica neLactobacillus. Zvidimbu zvakaiswa mu 2.5% glutaraldehyde, 1.25% paraformaldehyde uye 0.03% picric acid mu 0.1 M sodium cacodylate buffer (pH 7.4) kwemaawa maviri patembiricha yemumba. Mushure mekusuka, gadzirisai ne 1% osmium tetroxide (OsO4)/1.5% potassium ferrocyanide (KFeCN6) kwemaawa maviri, gezai katatu mumvura uye chengetai mu 1% uranyl acetate kweawa imwe, mozosuka kaviri mumvura, mozobvisa mvura kwemaminitsi gumi mu 50%, 70%, 90%, 100% alcohol. Masampuleti acho akaiswa mupropylene oxide kweawa imwe chete ndokuiswa mumusanganiswa we1:1 wepropylene oxide neTAAP Epon (Marivac Canada Inc. St. Laurent, CA). Masampuleti akaiswa muTAAB Epon uye akaiswa polymer pa60°C kwemaawa makumi mana nemasere. Resin yakachekwa uye yakatorwa neTEM ichishandisa microscope yemagetsi inonzi JEOL 1200EX (JEOL, Tokyo, Japan) ine kamera yeAMT 2k CCD (Advanced Microscopy Techniques, Corp., Woburn, Massachusetts, USA).
Kuedza kwese kwakaitwa katatu. Panguva yega yega, kushambidzwa kwemabhakitiriya kwakadyarwa katatu, zvichikonzera huwandu hwemapoinzi mapfumbamwe papoinzi imwe neimwe, avhareji yacho yakashandiswa sehuwandu hwemabhakitiriya ehutachiona ihwohwo. Kutsauka kwakajairwa kwakashandiswa sekukanganisa kwekuyera. Mapoinzi ese anoverengwa.
Kuderera kwehuwandu hwebhakitiriya muhuwandu hwe t = 0 min kwakaverengerwa uchishandisa fomura inotevera:
apo C0 ihuwandu hwebhakitiriya mumuenzaniso wekudzora panguva 0 (kureva mushure mekunge pamusoro paoma asi usati waiswa mukamuri) uye Cn ihuwandu hwebhakitiriya pamusoro mushure memaminitsi n ekusangana.
Kuti tinzwisise kuparara kwemabhakitiriya kwechisikigo panguva yekusangana nehutachiona kwemaminitsi makumi mana nemashanu, kuderedzwa kwehuremu hwebhakitiriya zvichienzaniswa nekudzora mushure memaminitsi makumi mana nemashanu kwakaverengerwawo seizvi:
apo Cn iri huwandu hwemabhakitiriya ari mumuenzaniso wekudzora panguva n uye Cn-Control iri huwandu hwemabhakitiriya ekudzora panguva n. Data rinoratidzwa sekudzikira kwelog zvichienzaniswa nekudzora (hapana kusangana neEWNS).
Munguva yekudzidza, kusanganiswa kwakati wandei kwevoltage uye daro pakati petsono ne counter electrode zvakaongororwa maererano nekuumbwa kweTaylor cone, kugadzikana kweTaylor cone, kugadzikana kwekugadzirwa kweEWNS, uye kudzokororwa. Kusanganiswa kwakasiyana-siyana kunoratidzwa muSupplementary Table S1. Zviitiko zviviri zvinoratidza hunhu hwakagadzikana uye hunodzokororwa (Taylor cone, kugadzirwa kweEWNS, uye kugadzikana nekufamba kwenguva) zvakasarudzwa kuti zviongororwe zvizere. Pamufananidzo. Mufananidzo 3 unoratidza mhedzisiro yekuchaja, saizi, uye zviri mukati meROS muzviitiko zvese. Mhedzisiro yacho yakapfupikiswawo muTafura 1. Kuti zviongororwe, ese Mufananidzo 3 neTafura 1 zvinosanganisira hunhu hweEWNS8, 9, 10, 11 yakambogadzirwa isina kugadziriswa (baseline-EWNS). Kuverengerwa kwekukosha kwestatistical uchishandisa two-tailed t-test kwakaburitswazve muSupplementary Table S2. Pamusoro pezvo, data rekuwedzera rinosanganisira zvidzidzo zvemhedzisiro yecounter electrode sampling hole diameter (D) uye daro pakati peground electrode netip (L) (Supplementary Figures S2 neS3).
(ac) Kugoverwa kwehukuru kwakayerwa neAFM. (df) Hunhu hwechaji yepamusoro. (g) Kutsanangurwa kweROS kweEPR.
Zvakakoshawo kuziva kuti pamamiriro ese ari pamusoro apa, ionization current yakayerwa yaive pakati pe2 ne6 μA uye voltage iri pakati pe -3.8 ne -6.5 kV, zvichikonzera kushandiswa kwesimba kusingasviki 50 mW kune iyi single EWNS generation contact module. Kunyangwe EWNS yakagadzirwa pasi pekumanikidzwa kwakanyanya, mazinga e ozone aive akaderera zvikuru, asingambopfuuri 60 ppb.
Mufananidzo Wekuwedzera S4 unoratidza minda yemagetsi yakaedzwa ye [-6.5 kV, 4.0 cm] uye [-3.8 kV, 0.5 cm] zvichiteerana. Paminda ye [-6.5 kV, 4.0 cm] uye [-3.8 kV, 0.5 cm], kuverenga kwemumunda kuri 2 × 105 V/m uye 4.7 × 105 V/m, zvichiteerana. Izvi zvinotarisirwa, sezvo muchiitiko chechipiri chiyero chevoltage-distance chakakwira zvikuru.
Pamufananidzo 3a, b panoratidza dhayamita yeEWNS yakayerwa neAFM8. Avhareji yemadhayamita eEWNS akaverengerwa aive 27 nm uye 19 nm yezvirongwa zve [-6.5 kV, 4.0 cm] uye [-3.8 kV, 0.5 cm], zvichiteerana. Pazviitiko zve [-6.5 kV, 4.0 cm] uye [-3.8 kV, 0.5 cm], kutsauka kwechiyero chejometri kwekugoverwa kuri 1.41 uye 1.45, zvichiteerana, zvichiratidza kupararira kwehukuru hwakamanikana. Kutsauka kwepakati uye kutsauka kwechiyero chejometri zviri pedyo zvikuru neEWNS yekutanga, pa25 nm uye 1.41, zvichiteerana. Pamufananidzo 3c panoratidza kupararira kwehukuru hweEWNS yenheyo yakayerwa uchishandisa nzira imwechete pasi pemamiriro akafanana.
Pamufananidzo 3d,e inoratidza mhedzisiro yekutsanangurwa kwechaji. Data iavhareji yekuyerwa kwe30 panguva imwe chete kwekuyera kwehuwandu (#/cm3) uye current (I). Ongororo inoratidza kuti avhareji yekuchaja paEWNS i22 ± 6 e- uye 44 ± 6 e- ye [-6.5 kV, 4.0 cm] uye [-3.8 kV, 0.5 cm], zvichiteerana. Vane surface charges yakakwira zvakanyanya zvichienzaniswa ne baseline EWNS (10 ± 2 e-), yakakura kaviri pane [-6.5 kV, 4.0 cm] uye yakakura kane kupfuura [-3 .8 kV, 0.5 cm]. Mufananidzo 3f unoratidza charge. data reBaseline-EWNS.
Kubva pamamepu ehuwandu hweEWNS (Zvifananidzo Zvekuwedzera S5 neS6), zvinogona kuonekwa kuti mamiriro ezvinhu e [-6.5 kV, 4.0 cm] ane zvidimbu zvakawanda kupfuura mamiriro ezvinhu e [-3.8 kV, 0.5 cm]. Zvakakoshawo kuziva kuti huwandu hwehuwandu hweEWNS hwakatariswa kusvika maawa mana (Zvifananidzo Zvekuwedzera S5 neS6), uko kugadzikana kwechizvarwa cheEWNS kwakaratidza mazinga akafanana ehuwandu hwezvikamu muzviitiko zvese zviri zviviri.
Pamufananidzo 3g inoratidza EPR spectrum mushure mekubvisa optimized EWNS control (background) pa [-6.5 kV, 4.0 cm]. MaROS spectra akaenzaniswawo neBaseline-EWNS scenario mubasa rakamboburitswa. Huwandu hweEWNS hunoita spin traps hwakaverengerwa kuva 7.5 × 104 EWNS/s, hwakafanana neBaseline-EWNS8 yakamboburitswa. MaEPR spectra akaratidza pachena kuvapo kwemarudzi maviri eROS, neO2- iri mhando huru uye OH• isina kuwanda. Pamusoro pezvo, kuenzanisa zvakananga kwepeak intensities kwakaratidza kuti maOptimized EWNS aive nehuwandu hweROS hwakakwira zvakanyanya zvichienzaniswa nebaseline EWNS.
Pamufananidzo 4 panoratidza kushanda zvakanaka kweEWNS muEPES. Data iri rakapfupikiswawo muTable I uye richienzaniswa nedata rekutanga reEWNS. Pazviitiko zvese zveEUNS, kuiswa kwacho kuri pedyo ne100% kunyangwe paine voltage yakaderera ye3.0 kV. Kazhinji, 3.0 kV inokwana kuisa 100%, zvisinei nekuchinja kwechaji yepamusoro. Pasi pemamiriro akafanana, kushanda zvakanaka kweBaseline-EWNS kwaingova 56% chete nekuda kwekuchaja kwavo kwakaderera (avhareji maerekitironi gumi paEWNS imwe neimwe).
Pamufananidzo 5 uye mutafura 2 inoratidza kukosha kwekusashanda kwetupukanana twakaiswa pamusoro pematomatisi mushure mekusangana ne40,000 #/cm3 EWNS kwemaminitsi 45 pamhando yepamusoro [-6.5 kV, 4.0 cm]. E. coli neLactobacillus innocuous zvakaiswa mujecha zvakaratidza kudzikira kukuru kwematanda 3.8 panguva yekusangana nematanda kwemaminitsi 45. Pasi pemamiriro akafanana, S. enterica yakaderedzwa ne2.2-log, nepo S. cerevisiae neM. parafortutum zvakaderera ne1.0-log.
Ma electron micrographs (Mufananidzo 6) anoratidza shanduko dzemuviri dzinokonzereswa neEWNS pamasero eEscherichia coli, Streptococcus, uye Lactobacillus asingakuvadzi zvichiita kuti asashande. Mabhakitiriya ekudzora aive nemasero asina kukuvadzwa, nepo mabhakitiriya akafumurwa akakuvadza masero ekunze.
Kutorwa kwemaelektroni nemaikorosikopu kwemifananidzo yekudzora uye mabhakitiriya akaonekwa pachena kwakaratidza kukuvara kwemembrane.
Ruzivo pamusoro pehunhu hwefizikisi yeEWNS yakagadziriswa pamwe chete runoratidza kuti hunhu (surface charge uye ROS content) hweEWNS hwakavandudzwa zvakanyanya zvichienzaniswa nedata rekutanga reEWNS rakabudiswa kare8,9,10,11. Kune rumwe rutivi, saizi yavo yakaramba iri mu nanometer range, yakafanana zvikuru nemhedzisiro yakambotaurwa kare, zvichivabvumira kuramba vari mumhepo kwenguva yakareba. Kupararira kwakaonekwa kunogona kutsanangurwa nekuchinja kwechaja yepamusoro kunosarudza saizi yeEWNS, kurongeka kweRayleigh effect, uye kugona kubatana. Zvisinei, sezvakatsanangurwa naNielsen et al. 22, chaja yepamusoro yepamusoro inoderedza evaporation nekuwedzera simba repamusoro/kumanikidzwa kwedonhwe remvura zvinobudirira. Mubhuku redu rekare8 dzidziso iyi yakasimbiswa nekuyedza kune microdroplets 22 neEWNS. Kurasikirwa nechaja panguva yekuwedzera kunogonawo kukanganisa saizi uye kubatsira mukugoverwa kwehukuru kwakaonekwa.
Pamusoro pezvo, muripo pachivako chimwe nechimwe ungangoita 22-44 e-, zvichienderana nemamiriro ezvinhu, izvo zvakakwirira zvakanyanya kana tichienzanisa neEWNS yekutanga, ine avhareji yekuchaja ye10 ± 2 maerekitironi pachivako chimwe nechimwe. Zvisinei, zvinofanira kucherechedzwa kuti iyi ndiyo avhareji yekuchaja yeEWNS. Seto et al. Zvakaratidzwa kuti muripo hauna kufanana uye unotevera kugoverwa kwakajairika kwe log-normal21. Zvichienzaniswa nebasa redu rekare, kupeta kaviri muripo wepamusoro kunowedzera kaviri kushanda kwekuisa muEPES system kusvika pa100%11.