Te matūhiko o te kikorangi metilīni: ngā kawehiko, ngā pūtorotoro hāoratanga-whakahekenga, me ngā pūoko

Ka whakahaere tētahi ākonga paerunga i te woltametri ā-huringa o te kikorangi metilīni ki tētahi kawehiko waro ā-karāhe, ka kite i tētahi takirua tihi mārama, ā, ka whakatau kua oti te pūoko. Kotahi wiki i muri mai, kua neke, kua heke, kua wāwāhi rānei ngā tihi, ā, kāore he whakamārama i te kawa mō te take. Kāore te waikano i rerekē. Kāore i oti te ariā i tūāpapa ai te inenga.

E toru ngā take e whai wāhi ai te kikorangi metilīni ki te matūhiko. Ka whakawhiti whakahokinga i ngā irahiko i ngā pūmanawa hiko ngāwari, ka piri ki ngā mata, ka waerautia hei kiriata, ā, ka here ki ngā waikawa karihi. He ariā motuhake ia mea, ā, he ara rerekē tō ia mea ki te hapa. Ka wehewehea ēnei e tēnei arotake: te takirua, te pānuitanga, te kawehiko whakarerekē, te mahi takawaenga, me ngā hanganga pūoko ka hangaia ki runga i aua tūāpapa.

Kotahi takirua, e rua āhua, kotahi iraoho

I te pH kūpapa, ka tuhia te tauhohenga matua hei katote tōrunga kua hāoratia, e tango ana i ngā irahiko e rua me te iraoho kotahi, kia puta ai te āhua leuco kua whakahekea, kāore ōna tae:

MB+ + H+ + 2e- gives LMB

I te pH 7, kei te takiwā o +11 mV te pūmanawa hāoratanga-whakahekenga o te kikorangi metilīni, e whakatauritea ana ki te kawehiko hauwai paerewa, e ai ki tētahi rangahau o nā tata nei mō te tikanga tauhohe o te waikano i Chemistry Europe. Nā te haere tahi o te iraoho kotahi me ngā irahiko e rua, ka neke te pūmanawa ōkawa ki te taha tōraro mā te 30 mV pea mō ia pikinga kotahi o te wae pH. Ko taua rōnaki te tohu tautuhi tuatahi e tika ana kia mau ki te mahara. Ki te neke tō tihi mā te 30 mV pea mō ia wae pH, ko te takirua e tūmanakohia ana tāu e mātakitaki ana. Ki te neke mā te 60 mV mō ia wae, kua rerekē te maha o ngā iraoho. Ki te tata kore rawa e neke, tērā pea nō tētahi kiriata mata te tohu, he matū waikawa-pāpā tōna ake, kaua nō te waikano kua rewa.

Ko ngā kawehiko tohutoro te tikanga tuarua hei whai. He rerekētanga kei ngā pūmanawa e whakatauritea ana ki Ag/AgCl, SCE, me NHE, mai i ngā tekau ki ngā rau o te millivolt, ā, ka neke anō ngā tau i te wairewa whakakī. Ka whakaingoatia te tohutoro o ia pūmanawa i tēnei tuhinga. Kāore e taea te whakamahi anō i tētahi pepa rangahau ki te kore e pērā. He wāhanga anō o te kōrero te rerekētanga hanganga o ngā āhua e rua: he katote tōrunga papatahi tētahi, he rāpoi ngohengohe kūpapa tētahi. Ka whakamāramatia whānuitia tēnei i te whārangi hoa mō te takirua hāoratanga-whakahekenga.

He aha tonu tā te kauwhata woltametri o te kikorangi metilīni e whakaatu ana

I runga i tētahi kawehiko waro ā-karāhe mā, kāore anō kia pania, i roto i te wairewa ārai phosphate āhua kūpapa, ko te tikanga ka puta i te kikorangi metilīni kua rewa tētahi tihi ā-anode kei te takiwā o te 0.15 ki te 0.18 V ki te taha tōraro o Ag/AgCl, me tētahi tihi ā-cathode kei te takiwā o te 0.20 ki te 0.25 V ki te taha tōraro o taua tohutoro anō. Ka neke ngā tūranga pū i runga i te tere matawai, te hītori o te mata, me te wairewa whakakī o te tohutoro. E ai ki tētahi inenga whai urunga tūmatanui o nā tata nei ki te waro ā-karāhe kāore anō kia pania, kei te takiwā o te 0.18 V ki te taha tōraro te tihi ā-cathode i te pH 7.4, i raro i ōna ake tikanga.

Ko te whakamārama pai rawa mō te takirua, he āhua whakahokinga. Mēnā he takirua whakahokinga tino pai, e rua ōna irahiko, ka tata ki te 30 mV te wehenga o ngā tihi. I te nuinga o te wā, he whānui ake, he hangarite-kore hoki ngā ngaru o te kikorangi metilīni, ā, ka uaua ake te whakamāramatanga nā te piringa ā-mata. He tohu tautuhi taua āhuatanga uaua, ehara i te ngangau. Ki te piki te ia o te tihi i te ōwehenga tōtika ki te tere matawai, e tohu ana tērā i te waikano kua piri ki te mata. Ki te piki te ia o te tihi i runga i te pakiaka tapawhā o te tere matawai, e tohu ana tērā i te waikano e tūringiringi mai ana i te wairewa. He maha ngā kauwhata tūturu e whakakotahi ana i ēnei e rua. Nā reira ka rerekē pea ngā teitei tihi o taua wairewa kotahi i runga i tētahi kawehiko kātahi anō ka whakakanapahia, me tētahi kua whakamahia kē.

Ka tāpiri te hāora kua rewa i tōna ake ia whakahekenga ki taua awhe pūmanawa anō. Nō reira ko te tikanga mō ngā mahi ine rahinga, ka tangohia te hāora i te tuatahi, ka whakaarohia rānei tōna pānga. Ka whakaparu hoki te kikorangi metilīni: ka whakarerekē te waikano kua piri i te mata i ia huringa. Nō reira he taunakitanga te nekeneke o ngā tihi i ngā matawai tukurua mō te kawehiko, ehara mō te matū e tātarihia ana.

Mai i te waikano kua rewa ki te kawehiko whakarerekē

Ka tīmata te pūoko koiora whai kawehiko kua whakarerekētia ki te kikorangi metilīni i tētahi kitenga māmā. He kaha te piri o te waikano ki te waro, nō reira ka whakarerekētia kē te kawehiko mā te rumaki noa ki te wairewa waikano. Ko te piringa ā-mata noa hoki te hanganga iti rawa te pūmautanga, nā te mea ka turuturu te waikano ki te wairewa anō. Ko ngā mea katoa atu i tēnei wāhanga he urupare ki taua turuturu.

Ko te whakautu kua tino whakatūturutia ko te poly(kikorangi metilīni) kua waerautia ā-hiko. Mā te tuku i te kawehiko ki ngā huringa hāoratanga i roto i te wairewa waikano, ka whakatakotoria he kiriata hohe ki te hāoratanga-whakahekenga. He tino pai ake te noho pūmau o taua kiriata i tō te waetahi kua piri noa ki te mata. E whakamahi ana te kawa paerewa o te momo Karyakin i te waikano e tata ana ki te 1 mM i roto i te wairewa ārai borate 0.02 M, tata ki te pH 9.1, me te konurehu pūhaumāota 0.1 M. Ka huri mai i te takiwā o te 0.40 V tōraro ki te 1.20 V tōrunga mō ngā huringa e tata ana ki te 30, e ai ki tētahi tuhinga whakapae nō Durham e tuhi ana i te tikanga. He mea nui te wairewa ārai kawakore: ka tupu te kiriata mā ngā āhua kua hāoratia ka puta i ngā pūmanawa tōrunga, ā, me tae te awhe pūmanawa ki aua āhua.

He rerekē ngā raruraru e whakatikaia ana e ētahi atu hanganga. Ka whakaae ngā kawehiko whakapiri waro me ngā kawehiko tā-mata kia iti iho te tōtikatanga kia taea ai te whakamahi kotahi, ka whakarere. Ka whakapiki ngā matū hiato whai ngongo nano, whai graphene rānei i te horahanga hohe, ā, ka whakakoi i ngā tihi. Ka whakamahia ngā kawehiko koura whai pūtorotoro e mau ana mā te thiol mō ngā pūoko waikawa karihi kei raro nei. Mā te here i raro i ngā kiriata Nafion ka pōturi te turuturu, engari ka pōturi hoki te urupare. He ōrite tonu te pātai hoahoa: ko tēhea momo hapa e whakaitihia ana e koe, ā, he aha te utu o taua whakaitinga.

Te ariā takawaenga: he kaikawe whakawhiti, ehara i te matū tauhohe

Ina whakamahia hei takawaenga hāoratanga-whakahekenga i te woltametri ā-huringa o te kikorangi metilīni, ka noho te waikano kua rewa hei kaikawe whakawhiti irahiko i waenga i tētahi matū e tātarihia ana, e uaua ana te tauhohe, me te kawehiko. Ka tango te waikano kua hāoratia i ngā irahiko mai i ngā tauhohenga matū o te tauira, ka hāoratia anō e te kawehiko te waikano kua whakahekea, ā, ka pūrongo te ia kua inea i te tere o te hurihanga tauhohe. Ko ngā kukūtanga e tūringiringi noa ana kei ngā tekau o te micromolar i te nuinga o te wā, kei te takiwā o te 10 ki te 60, kaua ko tētahi paerewa pūmau.

E toru ngā momo tauhohenga matū takawaenga ka hoki mai anō. Ka takawaengatia e te waikano te hāoratanga o NADH, tae atu ki te hurihanga tauhohe kua honoa ki te whākōkī, ā, ka whakakōkī ā-hiko ngā kiriata poly(kikorangi metilīni) i taua tauhohenga anō ki te mata. Ki te whakamahi tahi me ngā whākōkī hāora, ka taea te noho hei kaiwhiwhi irahiko horihori. I ngā pūnaha whākōkī peroxidase, ka whakawhiti te waikano kua whakahekea i ngā irahiko ki ngā matū takawaenga e whakaheke ana i te peroxide. Mā konei ka taea te kite i te hauwai peroxide i ngā pūmanawa iti kua whakamahia, he iti ake ai ngā pānga whakararuraru. Ka whakaatuhia whānuitia te tikanga tauhohe i tētahi rangahau o 2025 i Chemical Science mō te hāoratanga takawaenga o NADH. Ina nui te uta waikano, ka nui ake pea te tohu papamuri o te takawaenga me ngā tauhohenga matū o te hāora i te tohu tātari. Nō reira, he taurangi hei arotau te kukūtanga takawaenga, kaua he matū tauhohe hei tāpiri tuwhene.

Ngā pūoko waikawa karihi: te wāhi ka huri te herenga hei ia

Ka here te kikorangi metilīni ki te DNA mā te huinga o te kuhu ki waenga i ngā paparanga, te kukume hiko-pateko, me te pāhekoheko motuhake ki te guanine. Nō reira, ki te kī noa he matū kuhu-waenga, kāore tērā e whakaatu i te whānuitanga o ngā tauhohenga matū. Ka hurihia e ngā hoahoa pūoko taua herenga hei ia mā ngā hanganga motuhake e rua. Ko te pōhēhē he ōrite ēnei te hapa pānui tino auau i ēnei tuhinga rangahau.

I ngā hoahoa kāore he tapanga, ka hono te waikano herekore i roto i te wairewa ki te DNA pūtorotoro kua herea ki te mata, ā, ka whakarerekē te whakahononga whenu i te tohu. He hōputu noa e whakaweto ana i te tohu: ka whakaemi te pūtorotoro whenu-kotahi i te waikano, ka puta he tihi nui; engari ka whakarerekē te whakahononga ki te DNA whenu-rua i te taiao o te waikano, ā, ka heke te tohu. I te nuinga o te wā ka tae ngā paepae kitenga o ēnei hōputu ki te taumata nanomolar. I tētahi tauira, i whakanohoia he DNA kīnaki ki ngā ngongo nano waro pakitara-kotahi i runga i te koura. I pūrongotia he hononga rārangi mai i te 100 ki te 1000 nM, me tētahi paepae kitenga e tata ana ki te 7 nM i Electroanalysis.

I ngā hoahoa whai tapanga, ka herea te waikano mā te here kotahitanga ki tētahi pito o te pūtorotoro, ka herea tērā atu pito ki te koura mā te thiol, ā, ka whai te woltametri ngaru-tapawhā i te pūpūrongo kua herea. Ka whakawhānui ngā pūoko aptamer matūhiko e ahu mai ana i te kōpaki i tēnei ariā: mā te herenga o te matū whāinga ka whakaritea anō te āhua o te aptamer, ā, ka neke te pūpūrongo ki tētahi tūranga rerekē e pā ana ki te kawehiko. I pūrongotia e tētahi pūoko ochratoxin A, e whakamahi ana i te aptamer whai tapanga takirua thiol me te waikano i runga i te koura, he awhe 0.1 ki te 1000 pg mō ia mL, me tētahi paepae kitenga e tata ana ki te 0.095 pg mō ia mL. I whakaputaina tēnei i Analytica Chimica Acta.

He mea nui te wehewehenga mō te rapu hapa. I ngā hōputu kāore he tapanga, he wāhanga te waikano nō te wairewa, kei a ia tōna ake kukūtanga me tōna whakawhirinaki ki te pH. I ngā hōputu whai tapanga, he wāhanga te waikano nō te pūtorotoro, ā, ka pūrongo ngā huringa tohu i te tawhiti me te nekeneke, kaua i te tangohanga waikano.

Ngā tauira whākōkī me ngā tauira hiato

Ka noho hoki ngā kiriata poly(kikorangi metilīni) hei tūāpapa pupuri mō ngā pūoko whākōkī. I whakakotahi tētahi pūoko haukinia i tētahi kawehiko tā-mata me ngā matūriki nano koura me tētahi kiriata waikano, kātahi ka pania ki runga he pūnaha tauhohe glutamate dehydrogenase. Ka hāora te kiriata i te NADH, ā, ka pau taua NADH i te whākōkī i runga i te ōwehenga ki te haukinia: he awhe 0 ki te 300 micromolar, me tētahi paepae kitenga e tata ana ki te 0.65 micromolar, e ai ki te pūrongo i Biosensors. Ka kōrerotia te whānuitanga katoa o tēnei kaupapa i tētahi arotake o 2025 mō te waikano i roto i te rapunga matūhiko, i Analytica Chimica Acta.

Ngā āhuatanga me haere tahi me ia hua

Ka kōrero whānui te tohutoro hoa mō ngā tikanga whakamātautau ine rahinga mō te āta whai i ngā tikanga whakatika ine. Mō ngā hua matūhiko tonu, me noho ēnei tūemi ki ia pūkete taiwhanga:

Ehara te pūpūrongo i te rongoā

Ko te wehewehenga whakamutunga te take i hangaia ai tēnei whārangi. Mā te hekenga o tētahi tihi ngaru-tapawhā i te wā o te whakahononga whenu ka whakamātauhia kua neke tētahi tapanga hāoratanga-whakahekenga, kua rerekē rānei te herenga o te waikano. Kāore e whakamātauhia tētahi mea mō ngā mahi a te kikorangi metilīni i roto i te tangata e tiakina ana. He rāpoi kotahi tā te matū inenga me te mahi koiora e whakamahi ana, engari kāore he mea kē atu e ōrite ana: he rerekē ngā kukūtanga, he rerekē ngā taiao matū, ā, ko ngā kiriuhi me ngā whākōkī hei whakakapi i ngā kawehiko tauaro. Waiho ngā pātai maimoatanga ki ngā whārangi mahi koiora, ā, kia herea ngā kerēme mō ngā pūoko ki te kawehiko, te wairewa ārai, me te tikanga i whakaputa ai aua hua. He pūpūrongo te tapanga hāoratanga-whakahekenga. Ka whakaahua ngā pūpūrongo i te whakamātautau, kaua i te tinana.