Electrochemistry yemethylene blue: maelectrode, zviyereso zveredox, nemasensa

Mudzidzi ari kuita dhigirii repamusoro anoyera cyclic voltammogram yemethylene blue paelectrode yeglassy carbon, oona mapiki maviri akajeka, opedzisa achiti sensor yapera kugadzirwa. Kwapera vhiki, mapiki acho anenge afamba, adzikira, kana kupatsanuka, uye hapana mumaitiro akanyorwa chinotsanangura chikonzero chacho. Dhayi haina kuchinja. Pfungwa yakashandiswa pakuyera yakanga isina kukwana.

Methylene blue ine nzvimbo yayo mu electrochemistry nezvikonzero zvitatu. Inochinjana maerekitironi ichikwanisa kudzokera pachanga iri pamapotenshiyari asina kunyanya kukwirira, inonamatira pamusoro pezvinhu uye inoita mapolymer anoumba mafirimu, uye inosunga nucleic acids. Chimwe nechimwe ipfungwa yakasiyana, uye chimwe nechimwe chinokundikana nenzira yacho. Ongororo iyi inozvipatsanura: peya yeredox, chiratidzo chinoyerwa, electrode yakagadziridzwa, basa remupfuudziri, nemagadzirirwo emasensa anobva pazviri.

Peya imwe, zvimiro zviviri, purotoni imwe

Reaction huru papH iri pakati nepakati inowanzonyorwa secation imwe yakaita oksidheshoni ichitora maerekitironi maviri nepurotoni imwe kuti ipe chimiro cheleuco chakaita reduction, chisina ruvara:

MB+ + H+ + 2e- gives LMB

Potenshiyari yeredox yemethylene blue papH 7 iri pedyo ne +11 mV zvichienzaniswa nestandard hydrogen electrode, sezvakataurwa muongororo ichangoburwa yenzira dzinoita reaction yedhayi muChemistry Europe. Sezvo purotoni imwe ichifambidzana nemaerekitironi maviri, formal potential inotsvedza ichienda kudivi renegative neinenge 30 mV pakukwira kwepH neyuniti imwe neimwe. Mwero uyu wekuchinja ndiwo chiratidzo chekutanga chakakodzera kuyeukwa. Kana piki yako ichifamba neinenge 30 mV payuniti yepH, uri kuona peya inotarisirwa. Kana ichifamba ne60 mV payuniti, nhamba yemapurotoni yachinja. Kana isingatomboiti kufamba, chiratidzo chinogona kunge chichibva mufirimu riri pamusoro peelectrode rine chemistry yaro yeasidhi nebhesi, kwete mudhayi yakanyunguduka.

Kujaira kutaura electrode yereferensi ndiyo tsika yechipiri. Mapotenshiyari anotaurwa zvichienzaniswa neAg/AgCl, SCE, neNHE anosiyana nemakumi kusvika kumazana emillivolts, uye mushonga wakazadza electrode unowedzera kuchinja nhamba idzi. Potenshiyari imwe neimwe iri muchinyorwa chino inotaura referensi yayo. Chero pepa retsvakurudzo risingaiti izvi harigoni kushandiswazve. Musiyano wechimiro pakati pezvimiro zviviri izvi, cation yakati sandara nemorekuru isina charge inokwanisa kuchinja chimiro, ndiwowo chikamu chenyaya, uye peji rinoenderana nerino rinotaura nezvepeya yeredox rinoutsanangura zvakadzama.

Zvinonyatsoratidzwa nevoltammogram yemethylene blue

Paelectrode yakachena, isina kupfekedzwa, yeglassy carbon iri mubhafa yephosphate ine pH inenge iri pakati nepakati, methylene blue yakanyunguduka inowanzopa piki yeanode iri pasi peAg/AgCl ne0.15 kusvika 0.18 V uye piki yecathode iri pasi pereferensi imwe chete ne0.20 kusvika 0.25 V. Nzvimbo dzacho chaidzo dzinoshanduka nekumhanya kwescan, mashandisirwo akamboitwa pamusoro peelectrode, uye mushonga wakazadza electrode yereferensi, uye kuyera kuchangoburwa kunowanikwa pachena kwakaitwa paglassy carbon isina kupfekedzwa kunoisa piki yecathode pedyo ne0.18 V kudivi renegative papH 7.4 mumamiriro akashandiswa ipapo.

Peya iyi inotsanangurwa zvakanaka seyakada kukwanisa kudzokera pachanga iri, kana kuti quasi-reversible. Peya yakakwana inochinjana maerekitironi maviri ichidzokera pachanga iri yaizoratidza mapiki akaparadzana neinenge 30 mV. Masaisai emethylene blue anowanzova akafara uye asina kuenzana mativi, uye kunamatira pamusoro peelectrode kunoomesa kududzira. Kuoma uku chiratidzo chinobatsira kuongorora, kwete ruzha rusina basa. Current yepiki inokura zvakananga zvichienderana nekumhanya kwescan inoratidza dhayi yakanamatira pamusoro. Current yepiki inokura zvichienderana nesquare root yekumhanya kwescan inoratidza dhayi iri kufamba ichibva mumushonga nekudiffuser. Magirafu mazhinji anowanikwa mukuyera anosanganisa zvose izvi, ndokusaka mushonga mumwe chete uchigona kupa mapiki ane hurefu hwakasiyana paelectrode ichangobva kuporishwa neyakamboshandiswa.

Oxygen yakanyunguduka inopawo current yayo yereduction mukati memuganhu mumwe chete wepotenshiyari, saka basa rekuyera huwandu rinowanzoitwa mushure mekubvisa oxygen kana kuti richiverengera kukanganisa kunokonzerwa neoxygen. Uye methylene blue inosvibisa electrode: dhayi yakanamatira inochinja pamusoro payo pakutenderera kwega kwega, saka kufamba kwepiki pamascan anodzokororwa uchapupu pamusoro peelectrode, kwete pamusoro pechinhu chiri kuongororwa.

Kubva padhayi yakanyunguduka kuenda kuelectrode yakagadziridzwa

Biosensa inoshandisa electrode yakagadziridzwa nemethylene blue inotangira pachinhu chiri nyore kucherechedza. Dhayi inonamatira zvakasimba pacarbon, saka kungonyika electrode mumushonga wedhayi kunenge kwatoigadziridza. Kunamatirisa kwoga uku ndiko zvakare kugadzirwa kusinganyanyi kugadzikana, nokuti dhayi inobuda ichidzokera mumushonga. Zvimwe zvose zviri muchikamu chino inzira dzekugadzirisa kubuda uku.

Mhinduro yakanyanya kusimbiswa neongororo ndeyepoly(methylene blue) inogadzirwa neelectropolymerization. Kutenderedza electrode mumushonga wedhayi ichiitwa oksidheshoni kunogadzika firimu rinoshanda paredox rinoramba riri panzvimbo zviri nani zvikuru kupfuura monomer yakanamatira. Maitiro akajairika erudzi rwaKaryakin anoshandisa inenge 1 mM yedhayi mubhafa yeborate ye0.02 M pedyo nepH 9.1 ine 0.1 M potassium chloride, achitenderera kubva painenge 0.40 V kudivi renegative kusvika ku1.20 V kudivi repositive kwekutenderera kunenge 30, sezvakanyorwa muthesis yeDurham inotsanangura nzira iyi. Bhafa ine alkalinity inokosha: kukura kwefirimu kunoitika kuburikidza nezvimiro zvakaita oksidheshoni zvinogadzirwa pamapotenshiyari ari positive, uye muganhu wepotenshiyari unoshandiswa unofanira kusvika pazviri.

Mamwe magadzirirwo anogadzirisa mamwe matambudziko. Maelectrode ecarbon paste neanodhindwa nescreen anoderedza kunyatsorurama achiitira kuti araseke mushure mekushandiswa. Misanganiswa ine nanotubes kana graphene inowedzera nzvimbo inoshanda uye inoita kuti mapiki anyatsotsanangurika. Maelectrode egoridhe ane maprobe akasungirirwa nethiol anoshandiswa mumasensa enucleic acid ari pasi apa. Kubatirira dhayi pasi pemafirimu eNafion kunononotsa kubuda kwayo, asi kuchinonotsawo kupindura kwesensor. Mubvunzo wekugadzira unogara wakafanana: ndeipi nzira yekukundikana yauri kudzivirira, uye chii chawarasikirwa nacho kuti uidzivirire?

Pfungwa yemupfuudziri: kufambisa maerekitironi, kwete reagent

Semupfuudziri weredox mucyclic voltammetry yemethylene blue, dhayi yakanyunguduka inofambisa maerekitironi pakati pechinhu chiri kuongororwa chisingachinjani nawo nyore neelectrode. Dhayi yakaita oksidheshoni inotora maerekitironi kubva kumareaction ari musampuli, electrode yoita oksidheshoni zvakare padhayi yakaita reduction, uye current inoyerwa inoratidza mwero wekufamba kwemareaction aya. Concentration dzinowanzoshandiswa dzedhayi inodiffuser yakasununguka dziri mumakumi emicromolar, dzinenge 10 kusvika 60, pane kuva nechiyero chimwe chakatarwa.

Mareaction matatu anoshandisa mupfuudziri anowanzodzokororwa. Dhayi inopfuudzira oksidheshoni yeNADH, kusanganisira kutenderera kwemareaction kwakabatana nemaenzyme, uye mafirimu epoly(methylene blue) anoita electrocatalysis yereaction imwe chete pamusoro peelectrode. Kana paine oxidases, inogona kushanda sechinotora maerekitironi chakagadzirwa. Muzvirongwa zvine peroxidase, dhayi yakaita reduction inofambisa maerekitironi ichiaendesa kuzvimiro zvepakati zvinoita reduction yeperoxide, izvo zvinobvumira kuona hydrogen peroxide pamapotenshiyari akaiswa ari pasi, apo kukanganiswa kunenge kuri kushoma. Ongororo ya2025 muChemical Science yeoksidheshoni yeNADH inoshandisa mupfuudziri inotsanangura nzira yacho zvakadzama. Kana dhayi yakawandisa, chiratidzo chekumashure chinobva kumupfuudziri nemareaction eoxygen zvinogona kudarika chiratidzo chekuongorora, saka concentration yemupfuudziri chinhu chinofanira kugadziridzwa kuti chinyatsokodzera, kwete reagent inongowedzerwa yakawandisa.

Masensa enucleic acid: apo kusunga kunova current

Methylene blue inosunga DNA kuburikidza nemusanganiswa wekupinda pakati pezvikamu zvayo, kukwezvana kwemacharge, nekudyidzana kwakanangana neguanine, saka kungoti inopinda pakati pezvikamu zveDNA chete kunoderedza kutsanangurwa kwechemistry yacho. Magadzirirwo emasensa anoshandura kusunga uku kuva current munzira mbiri dzakasiyana, uye kudzivhiringidza ndiko kukanganisa kunowanzoitika pakuverenga zvinyorwa zvetsvakurudzo iyi.

Mumagadzirirwo asina label, dhayi yakasununguka iri mumushonga inobatana neDNA yeprobe yakasungirirwa pamusoro peelectrode, uye kubatana kwetambo dzeDNA kunochinja chiratidzo. Imwe nzira inowanzoitwa ndeyekudzikira kwechiratidzo: probe ine tambo imwe inounganidza dhayi ichipa piki huru, ukuwo kubatana kwayo kuita DNA ine tambo mbiri kuchichinja mamiriro akatenderedza dhayi uye chiratidzo chodzikira. Nzira idzi dzinowanzosvika pamiganhu yekuona iri pananomolar. Mumwe muenzaniso wakaisa DNA inopindirana pane carbon nanotubes dzine rusvingo rumwe dziri pagoridhe, ukataura kuenderana kwakatwasuka kubva pa100 kusvika 1000 nM nemuganhu wekuona uri pedyo ne7 nM muElectroanalysis.

Mumagadzirirwo ane label, dhayi inosungirirwa necovalent bond kune rumwe rutivi rweprobe, rumwe rutivi ruchisungirirwa kugoridhe kuburikidza nethiol, uye square wave voltammetry inotevera chiratidziro chakasungirirwa. Masensa eelectrochemical aptamer anoshandisa kupeta anowedzera pfungwa iyi: kusunga chinhu chakanangwa kunorongazve aptamer uye kunofambisa chiratidziro zvichienzaniswa neelectrode. Sensor yeochratoxin A yakashandisa aptamer ine thiol nedhayi semalabel maviri pagoridhe yakataura huwandu kubva pa0.1 kusvika 1000 pg per mL nemuganhu wekuona uri pedyo ne0.095 pg per mL, yakabudiswa muAnalytica Chimica Acta.

Musiyano uyu unokosha pakutsvaga zvinokonzera matambudziko. Mumagadzirirwo asina label, dhayi chikamu chemushonga chine concentration yacho uye kutsamira kwayo papH. Mumagadzirirwo ane label, dhayi chikamu cheprobe, uye kuchinja kwechiratidzo kunoratidza daro nekufamba, kwete kutorwa kwedhayi.

Mienzaniso inoshandisa maenzyme nemisanganiswa

Mafirimu epoly(methylene blue) anosungirirawo masensa anoshandisa maenzyme. Imwe sensor yeammonium yakabatanidza electrode yakadhindwa nescreen nemanoparticles egoridhe nefirimu redhayi, ichibva yapfekedza pamusoro payo zvinhu zvemareaction eglutamate dehydrogenase. Firimu rinoita oksidheshoni yeNADH uku enzyme ichiishandisa muhuwandu hunoenderana neammonium: 0 kusvika 300 micromolar nemuganhu wekuona uri pedyo ne0.65 micromolar, sezvakataurwa muBiosensors. Mufananidzo wakazara webasa iri unotsanangurwa muongororo ya2025 yekushandiswa kwedhayi mukuona neelectrochemistry muAnalytica Chimica Acta.

Mamiriro anofanira kuperekedza mhedzisiro imwe neimwe

Chinyorwa chinofambidzana nerino pamusoro pemaitiro ekuongorora huwandu chinotsanangura zvinofanira kutevedzwa pakugadzirisa zviyereso zvakazara. Pamhedzisiro yeelectrochemistry kunyanya, zvinhu izvi zvinofanira kuva murekodhi imwe neimwe yerabhoritari:

Chiratidziro hachisi kurapa

Musiyano wekupedzisira ndiwo unoita kuti peji rino rivepo kuti uusimbise. Kudzikira kwepiki yesquare wave pakubatana kwetambo dzeDNA kunoratidza kuti label yeredox yafamba kana kuti kusunga kwedhayi kwachinja. Hakuratidzi chinhu pamusoro pezvinoitwa nemethylene blue mumurwere. Chemistry yekuyera nekushanda mumararamiro zvinongogovana morekuru, hapana chimwe: concentration dzakasiyana, zvinhu zvakapoteredza zvakasiyana, uye mamwe maelectrode akasiyana anotsiviwa nemamembrane nemaenzyme. Chengetai mibvunzo yekurapa pamapeji ekushanda mumararamiro, uye chengetai zvinotaurwa nezvemasensa zvakabatana neelectrode, bhafa, nenzira yekuyera zvakazviburitsa. Label yeredox chiratidziro. Zviratidziro zvinotsanangura kuyera, kwete muviri.