I-Methylene Blue Novithamini C: Kungani Isixazululo Singaphelelwa Umbala

Ufaka ithebhulethi likavithamini C engilazini enesixazululo se-methylene blue esiluhlaza okwesibhakabhaka, uxove, bese ubuka umbala ulokhu ufiphala. Ngemva komzuzu uketshezi lubukeka njengamanzi nje. Kulula ukuphetha ngokuthi uvithamini C ubhubhise idayi noma uyenze yangabe isasebenza.

Leyo ndlela yokucabanga ayilungile, futhi lelo phutha libalulekile. Okubonayo kuwukushintsha kwesimo se-oxidation okungahlehliswa, hhayi ukubhujiswa. Idayi isekhona. Uma izimo zivuma, umbala uyabuya.

Izimo ezimbili zedayi

I-methylene blue inezimo ezimbili ezichazwe kahle. Isimo sayo esenziwe i-oxidation, esivame ukubhalwa ngokuthi MB+, sinesistimu yezindandatho ezixhumene ngokuhlanganyela kwama-electron, enwebekile, emunca ukukhanya ngamandla eduze kuka-664 nm. Lokho kumuncwa kokukhanya yikho okubangela umbala oluhlaza okwesibhakabhaka. Isimo esenziwe i-reduction, i-leucomethylene blue (LMB), asisenalo lelo bhande elinamandla lokumunca ukukhanya okubonakalayo, ngakho isixazululo esihlanjululiwe sibukeka singenambala.

Cabanga ngedayi njengesigcini esincane sama-electron esingashajwa kabusha. Ukuyishaja ngama-electron ne-proton kuyayiqeda umbala. Ukukhipha lawo ma-electron kubuyisela umbala:

MB+ + H+ + 2e- to LMB (engenambala)

Uvithamini C unikeza lokho kushaja. I-ascorbate yenziwa i-oxidation iye ku-dehydroascorbate futhi inikele ngokulingana kwama-electron amabili okwenza i-reduction. Ngakho, ekubalweni okulula kwezimo eziphelele, i-mole eyodwa ye-ascorbate yenza i-reduction cishe ku-mole eyodwa ye-MB+. Ezixazululweni zangempela zaselabhorethri ukubala kuyinkimbinkimbi kakhulu ngoba umoya-mpilo oncibilikile uncintisana ngawo lawo ma-electron. Yingakho ngokuvamile kudingeka i-ascorbate eyeqile ukuze isixazululo sihlale singenambala.

Le nqubo akudingeki ibe isinyathelo esisodwa esiqondile sokudluliswa kwama-electron amabili. Ama-radical nezimo eziphakathi nendawo ezenziwe i-reduction ngokwengxenye kuyabamba iqhaza, futhi indlela eqondile iyashintsha ngokuya ngesincibilikisi, izinga lobumuncu nokugxila. Nokho, umphumela wokugcina uyafana. I-MB+ eluhlaza okwesibhakabhaka iba yi-LMB engenambala, futhi uvithamini C uyasetshenziswa aphele kule nqubo.

Kungani ukunyakazisa kubuyisa umbala oluhlaza okwesibhakabhaka

Indlela evamile yokwenza lesi sivivinyo ekilasini inesigaba sesibili. Shiya ibhodlelana elingenambala linganyakaziswa, futhi lihlala lingenambala. Linyakazise, bese umbala oluhlaza okwesibhakabhaka uyabuya. Linda, bese uyafiphala futhi.

Okubuyisela umbala umoya-mpilo. I-O2 encibilikile yenza i-oxidation ku-LMB ibuyele ku-MB+, ngakho ukunyakazisa akuvusi ukusebenza kwedayi. Kugcwalisa umoya-mpilo oncibilikile ngokuxuba umoya osesikhaleni esingenhla koketshezi noketshezi, okusheshisa ukusabela okubuyela emuva. Uma nje kusekhona i-ascorbate esele, i-MB+ esiphinde yakheka yenziwa i-reduction futhi. Lokhu kudala umjikelezo ojwayelekile: ukuphumula kwenza kungabi nambala, ukunyakazisa kubuyisa okuluhlaza okwesibhakabhaka, ukulinda kwenza kungabi nambala futhi. Lapho i-ascorbate isiphelile, umoya-mpilo unqoba unomphela futhi isixazululo sihlala siluhlaza okwesibhakabhaka.

Yingakho umboniso we-methylene blue novithamini C uthinteka ngokuma nobukhulu besitsha. I-cuvette evaliwe enesikhala esincane somoya ngaphezu koketshezi ihlala ingenambala isikhathi eside kune-beaker ebanzi. Ukufaka umoya ngamandla kufinyeza isigaba sokungabi nambala. Ngakho noma ubani obika lesi sivivinyo kufanele asho izimo zomoya-mpilo, hhayi amanani ama-reagent kuphela.

Umboniso olawulwayo nezimo zawo

Isithombe sekhava salesi sihloko sibonisa ukuqhathanisa okuhlosiwe: isampula yokulawula ye-MB+ eluhlaza okwesibhakabhaka eduze kwesampula ye-LMB eyenziwe i-reduction nge-ascorbate, ngaphansi kokukhanya okufanayo. Ukuze umphumela ukwazi ukuphindwa, gcina kungashintshi zonke izici eziguqula isivinini:

Thatha izithombe zawo womabili amabhodlelana ngezikhathi ezinqunyiwe, ngokwesibonelo ngemva kwemizuzu engu-0, 1, 5, no-15, bese uwanyakazisa futhi uthatha izithombe futhi. Ibhodlelana elikhishwe umoya nge-nitrogen kufanele lihlale lingenambala isikhathi eside kunawo wonke. Ibhodlelana elifakwe umoya kufanele libuye libe luhlaza okwesibhakabhaka ngokushesha ngemva kokunyakaziswa. Uma isampula ingaphinde ibe luhlaza okwesibhakabhaka ngisho noma inyakaziswa futhi ifakwa umoya, sola ukuwohloka okungahlehliseki kunokuba kube i-reduction elula.

Abakha izingxube basebenzisa umqondo ofanayo ngezinga elikhulu. Indlela i-methylene blue eziphatha ngayo engxubeni incike esimweni esiphelele se-redox nasendleleni ingxube eyakhiwe ngayo. Ukuhlolwa kokuzinza kufanele kurekhode i-pH, umoya-mpilo oncibilikile, inani lokukhanya elitholakele nezinsimbi ezincane kakhulu, kanye nokubonwa kombala.

I-pH, ukukhanya nokugxila kudonsela ezinhlangothini ezihlukene

Abaqalayo bavame ukubuza ukuthi i-asidi noma i-base kuyakusheshisa yini ukusabela. Impendulo eqotho iwukuthi i-pH ithinta izingxenye ezimbili ezihlukene zomjikelezo. Ezimweni ezinamanzi ne-asidi, ukutholakala kwama-proton kungasheshisa isinyathelo lapho i-ascorbate yenza i-reduction ku-MB+. Kodwa i-LMB ngokwayo imelana kakhulu nokwenziwa i-oxidation ngomoya uma isesimweni esine-asidi, futhi yenziwa i-oxidation kabusha ngokushesha kakhulu lapho i-pH ikhuphuka. Ngakho isampula ene-asidi ingaphelelwa umbala ngokushesha bese ihlala ingenambala, kanti isampula ene-alkali iphelelwa umbala futhi ibuye ibe luhlaza okwesibhakabhaka ngokushesha. Kokubili lokhu okubonwayo kulungile ngaphansi kwezimo zakho.

Ukukhanya kwengeza indlela ehlukile. I-methylene blue enikwe amandla ukukhanya ifinyelela esimweni se-triplet esihlala isikhathi eside, lapho kwenzeka khona ukudluliswa kwama-electron ne-ascorbate nomoya-mpilo. Leyo khemistri ebangelwa ukukhanya ingasheshisa ukuphela kombala, ibuyisele umbala, noma ikhiqize izinhlobo zomoya-mpilo ezisabela kalula, kuye ngobude begagasi, izinga lomoya-mpilo nokugxila. Phatha ukukhanyisa njengesici sesivivinyo futhi ukurekhode.

Ukugxila kunquma ukuthi yiluphi uhlangothi olunqobayo. I-ascorbate eningi isho ukuphela kombala ngokushesha nemijikelezo eminingi yokunyakazisa nokufiphala. Idayi eningi idinga ama-electron okwenza i-reduction amaningi ngokwesilinganiso esifanayo. Umoya-mpilo oncibilikile omningi uvuna umbala oluhlaza okwesibhakabhaka. Lapho idayi igxile kakhulu kuvela enye inkinga, ngoba i-methylene blue iyazihlanganisa ibe ama-dimer namaqoqo aneziboniso ze-spectrum ezishintshile. Ngakho ukuphinda kabili inani ledayi akusaphindi kabili indlela efanayo yokuziphatha.

Ingabe uvithamini C wenza i-methylene blue ingabe isasebenza?

Lona ngumbuzo oyisisekelo sokusesha okuningi nge-methylene blue novithamini C, futhi udinga impendulo eqondile. Cha, ukuphela kombala akusho ukuthi idayi yenziwe yangabe isasebenza. Ingxenye yemolekyuli ebangela umbala ishintshe isimo, kodwa umongo we-phenothiazine nokusebenza kwayo kwe-redox kusekhona esixazululweni. Ukusabela kungahlehliswa ngumoya, futhi isimo esenziwe i-reduction naso siyasabela: i-LMB ayinashaji kagesi futhi ithanda amafutha kakhulu uma iqhathaniswa ne-MB+, kanti emsebenzini owenziwa ngamaseli idlula olwelwesini ngaphambi kokwenziwa i-oxidation kabusha ngaphakathi.

Imibhalo yesayensi ephathelene namaseli iyalicacisa leli phuzu. Emaselini e-endothelium akhuliswa elabhorethri, i-methylene blue esekugxileni okuphansi okulinganiswa nge-micromolar ivuselela ukusebenza kwendlela ye-pentose phosphate kuyilapho yenza i-oxidation ku-NADPH ne-NADH. Ngaphezu kokugxila okungaba ngu-5 micromolar, inyusa izimpawu zezinto ezenza i-oxidation ngaphakathi kwamaseli lapho kungekho ukwesekwa yi-glucose. Amaseli afakwe i-ascorbate enza i-oxidation kuleyo ascorbate ngokuqhubekayo lapho echayeka kudayi, futhi inani le-ascorbate elifakiwe licindezela kuphela ingxenye yesignali yezinto ezenza i-oxidation, njengoba kubikwe ocwaningweni lwe-redox yedayi kumaseli e-endothelium. Ngamanye amazwi, i-ascorbate ibamba iqhaza ekudluliselaneni kwe-redox. Ayicishi ukusebenza kwedayi.

Ukukhanya kwenza lokhu kucace nakakhulu. Lapho kukhanyisiwe, izingxube ze-methylene blue, i-ascorbate nomoya-mpilo zisebenzisa umoya-mpilo, ziqongelele i-hydrogen peroxide, futhi uma kukhona insimbi esebenza njenge-catalyst zikhiqize i-radical ye-hydroxyl ngekhemistri ye-Fenton, njengoba kuboniswe yizivivinyo zokubamba ama-radical nge-spin trapping nokulinganisa ukusetshenziswa komoya-mpilo. Ama-radical e-hydroxyl angalimaza ama-biomolecule ngendlela engahlehliseki futhi awohloze idayi ngokwayo. Ngakho isampula ephelelwe umbala unomphela ngaphansi kokukhanya nokungcoliswa yinsimbi ayibonisi i-reduction engenazo izinqubo eziseceleni. Kungenzeka ibonise ukubhujiswa yikhemistri eseceleni.

Lokho isixazululo esingenambala esingakufakazeli

Iziphetho ezintathu ezivamile zeqa ubufakazi futhi kufanele zigwenywe emanothini aselabhorethri, kumalebula nakuma-slide okufundisa.

Okokuqala, ukungabi nambala akusho ukungabi yingozi. I-LMB kanye nomoya-mpilo nezinsimbi ezincane kakhulu kungaqhubekisela izindlela ze-peroxide nama-radical, ikakhulukazi ngaphansi kokukhanya. Ukuqinisekisa ukungabi yingozi kudinga isayensi yobuthi, hhayi ukukalwa kombala.

Okwesibili, ukungabi nambala akusho ukuthi ukungcola kususiwe. Idayi nezinto ezisebenzisana nayo ku-redox kusekhona. Izinto ezichithekile, uketshezi olukhishwa njengemfucuza nezinto ezinamabala azilungiswa ngokungeza i-ascorbate. Kudingeka ukuqinisekiswa ngokuhlaziya, okuyisihloko esidingidwa emikhubeni yokuhlola izinsalela nokususwa kokungcola.

Okwesithathu, ukungabi nambala akuchazi uhlelo oluwusizo lokusebenzisa lezi zinto ndawonye. Ukusabela okwenzeka eshubhini lokuhlola akusho lutho ngokumuncwa, ukusatshalaliswa ezicutshini, imithamo noma ukuphepha kokusebenzisana kwazo kubantu. Noma ubani ocabanga ukuhlanganisa lezi zinto ezimbili ngenjongo yezempilo kufanele aqale afunde imibhalo ephathelene nokusebenzisana nokuphepha, futhi abonisane nemithombo efanelekayo kunokuba afinyelele eziphethweni esuselwe ebhodlelaneni.

Ukuqonda okufanele kunomkhawulo omncane kodwa kuwusizo kakhulu. I-methylene blue ne-ascorbate kuyimodeli encane yomjikelezo we-redox: uvithamini C unikela ngama-electron, idayi iphelelwa umbala, umoya-mpilo uthatha lawo ma-electron, umbala ubuye, bese ukukhanya, i-pH, ukugxila nensimbi kunquma isivinini nemikhiqizo eseceleni. Uma lowo mqondo usucacile, umboniso uyeka ukuba iqhinga bese uba indlela yokuthola ukuthi kwenzekani. Uma isampula yakho iziphatha ngendlela ehlukile, hlola ukufinyelela komoya-mpilo, inani lokukhanya elitholakele, i-pH nokungcoliswa yizinsimbi ngaphambi kokungabaza idayi.