Imethylene blue neleucomethylene blue: isibini esinye seredox, imibala emibini

Umfundi ugalela amathontsi ambalwa edayi eluhlaza okwesibhakabhaka kwiflaski, ayijikelezise, aze abukele umbala unyamalala. Uyayishukumisa iflaski, uze umbala oluhlaza okwesibhakabhaka ubuye. Akukho nto yongeziweyo okanye esusiweyo phakathi kwezi meko zimbini ngaphandle kwee-elektroni nokudibana nomoya. Loo flaski iqulethe wonke umxholo weli nqaku: imethylene blue neqabane layo elincitshisiweyo, ileucomethylene blue, eziguqulelana kwisibini seredox esinokubuyela umva, apho umbala ubonisa iziphumo.

Eyona nto iluncedo iza kuqala. Ukutshintsha kombala apha akusosiphumo esingundoqo. Kungumqondiso wohlalutyo. Nabani na owenza imixube ngemethylene blue, oyisebenzisela ititration, okanye ofundisa ngayo ufanele akwazi ukubhala isiqingatha sereakshini ngaphandle kokujonga, achaze iimeko eziqhubela ngasekhohlo okanye ngasekunene, aze abize izinto ezingacocekanga ezenza iziphumo zingacaci.

Isibini kwiequation enye

Imethylene blue eyenziwe ioksideshini yikationi yemethylthioninium: isakhiwo esisicaba sephenothiazinium esinesalfure nenitrojeni kwiringi ephakathi, kunye neqela ledimethylamino kwisiphelo ngasinye, esibonelelwa njengetyuwa yeklorayidi. IPubChem iyibhalisa njengemethylthioninium chloride, C.I. Basic Blue 9. Emanzini, imonomer ifunxa ukukhanya kufutshane ne-664 nm, nto leyo evelisa umbala oluhlaza okwesibhakabhaka obonwa liliso.

Ileucomethylene blue encitshisiweyo (LMB) inesakhiwo esisiseko esifanayo, kodwa initrojeni yeringi ephakathi ifumene iprotoni, yaye ichromophore iphazamisekile. Ayinantlawulo yombane kwi-pH ekufutshane nengathathi cala, yaye iphantse ingabi nambala, ifunxa ukukhanya okubonakalayo kancinci kakhulu, kodwa inommandla owomeleleyo wokufunxa ukukhanya kwe-ultraviolet kufutshane ne-258 nm (ingxelo yePubChem yeleucomethylene blue, CAS 613-11-6). Inani leeprotoni kwisiqingatha sereakshini lixhomekeke kwi-pH, kuba uhlobo oluncitshisiweyo lufumana iiprotoni kwi-asidi (amaxabiso aqikelelweyo e-pKa akufutshane no-4.5 no-5.8). Iimeko ezintathu zigubungela uluhlu olusetyenziswa ngokuqhelekileyo:

MB(+) + 2 e(-) + H(+) <=> LMB, luhlaza okwesibhakabhaka <=> ayinambala (kwi-pH ekufutshane nengathathi cala, 1 iprotoni)

MB(+) + 2 e(-) + 2 H(+) <=> LMBH(+), luhlaza okwesibhakabhaka <=> ayinambala (ine-asidi ephakathi, 2 iiprotoni)

MB(+) + 2 e(-) + 3 H(+) <=> uhlobo lweleuco olufumene iiprotoni ezimbini (ine-asidi kakhulu, 3 iiprotoni)

Zontathu ezi ndlela zokubhala zichaza isibini esifanayo kwiimeko ezahlukeneyo zokufumana iiprotoni, ingongoma ephathwa ngokucwangcisiweyo kuncwadi lokuziphatha kweredox kwiidayi zethiazine. Ukuxhomekeka kwi-pH kulandela iequation kaNernst ye-Ox + mH(+) + 2e(-) <=> Red, enika ukuthambeka okumalunga no-29.6, 59.2, okanye 88.7 mV ngeyunithi nganye ye-pH xa m = 1, 2, okanye 3. Ukuthambeka okulinganisiweyo kufutshane no-28, 58, no-87 mV ngeyunithi nganye ye-pH kuqinisekisa le ndlela yokwahlula, ngoko ipotenshiyali exeliweyo ngaphandle kwe-pH yayo ayinantsingiselo.

Into exelelwa ngiequation umenzi wemixube

Iinyaniso ezintathu zivela kwistoichiometry. Okokuqala, ii-elektroni ezimbini ngemolekyuli nganye zithetha ukuba imethylene blue sisalathisi nomlamli wee-elektroni ezimbini, hayi umthuthi we-elektroni enye, kwireakshini yayo iyonke. Okwesibini, iiprotoni ziyathatha inxaxheba, ngoko ipotenshiyali esesikweni itshintsha ngokwe-pH njengoko kuchaziwe ngasentla. Okwesithathu, ipotenshiyali esesikweni kwi-pH 7 ikufutshane ne-+0.011 V xa ithelekiswa ne-electrode yehayidrojeni esemgangathweni (malunga ne-+0.53 V kwi-pH 0), nto leyo ebeka esi sibini phakathi kwezinto ezenza ioksideshini ngobulali: sinamandla ngokwaneleyo okuthatha ii-elektroni kubanikeli abalungileyo abafana ne-NAD(P)H okanye iascorbate, kodwa sibuthathaka ngokwaneleyo ukuzinika ioksijini enyibilikileyo okanye amaziko e-ferric. Eso sikhundla siphakathi sesona sizathu sokuba idayi ijikeleze endaweni yokuxinga kwelinye icala.

Uxinaniso longeza omnye umba. Xa lungaphezulu kweemicromolar ezimalunga nekhulu emanzini, ngokuhambelana nexabiso elixeliweyo lesigxina sokwahlukana kwedimer ibe ziimonomer elikufutshane ne-170 ukuya kwi-250 uM kwi-pH 7, iicationi ezenziwe ioksideshini ziyapakishana zibe ziidimer neendibaniselwano ezinkulu, ezinommandla wokufunxa otshintshele kufutshane ne-610 ukuya kwi-615 nm. Ngoko ispektrum esibonakala singekho kwincopho elindelekileyo sinokuthetha ukudibana kweemolekyuli, kungekhona ukungacoceki. Nciphisa uxinaniso kuqala, uze uvavanye.

Iimeko eziqhuba icala ngalinye

Itheyibhile engezantsi sisalathiso sokusebenza elebhu. Ukuncitshiswa kufuna umnikeli wee-elektroni; ukuphinda kwenziwe ioksideshini kufuna umamkeli wee-elektroni, yaye umoya udla ngokwanela.

Umqolo ngamnye uthobela iequation efanayo. Kutshintsha kuphela amandla aqhubayo. Yiloo ntsingiselo yokuba isibini sinokubuyela umva: indlela iyafana, ihanjwa kumacala achaseneyo phantsi kweemeko ezichaseneyo.

Ukuchazwa kwebhotile eluhlaza okwesibhakabhaka

Lo mboniso ufanele uchazelwe ngokucacileyo indlela osebenza ngayo kuba ubonisa isibini ngomlinganiselo omncinci. Kwisisombululo seglucose esinealkali, ibheyisi ikhuthaza ukuguquka kweglucose ibe yienol, ize ienediolate evelayo inciphise imethylene blue ibe yileucomethylene blue, ngoko iflaski ayibi nambala. Ukushukumisa kunyibilikisa ioksijini ekwindawo engaphezulu kolwelo, ioksijini iphinde yenze ioksideshini kuhlobo lweleuco, uze umbala oluhlaza okwesibhakabhaka ubuye. Ukuyeka iflaski ingashukumi kuphelisa ioksijini enyibilikileyo kufutshane nommandla wereakshini ongaphezulu, ize iglucose iphinde yoyise. Umjikelo uyaphindaphinda de iglucose iphele, yaye ukushukumisa ngakunye kubonisa iequation kaNernst: nyusa umsebenzi wento eyenza ioksideshini, luze ulungelelwano lutshintshele kwicala lombala oluhlaza okwesibhakabhaka.

Iradical ephakathi

Ireakshini iyonke ihambisa ii-elektroni ezimbini, kodwa amanyathelo ayo asisiseko ahambisa enye ngexesha. Phakathi kwecationi eluhlaza okwesibhakabhaka nohlobo lweleuco olungenambala kukho iradical ephakathi yesemiquinone, edla ngokuguquka nge-disproportionation ibuyele kwezi ntlobo zimbini endaweni yokufumba. Ipotenshiyali yayo ye-elektroni enye ekufutshane nothabatha u-0.23 V kwi-pH 7 isezantsi kakhulu kunendawo ephakathi yereakshini iyonke yee-elektroni ezimbini, nto leyo ebangela ukuba iradical ihlale iluhlobo oluncinci kwimeko ezinzileyo. Ibalulekile ngezizathu ezibini. Xa ikhanyisiwe, idayi ifikelela kwiimeko ezivuselelweyo ezivula iindlela zeeradical, yiyo loo nto izisombululo zemethylene blue zibuthathaka ekukhanyeni, nokuba kutheni ikhemistri yokukhanya ifanele ibe yinxalenye yayo nayiphi na inkqubo yovavanyo lokuzinza. Kwaye xa uxinaniso luphezulu, uhlobo olwenziwe ioksideshini lwenza iidimer, nto leyo etshintsha ispektrum nesantya sereakshini esibonakalayo ngaphandle kokutshintsha isibini esisiseko. Akukho nanye kwezi nyaniso ethintela ukubuyela umva. Zombini zichaza izinto eziqatshelwayo ebezinokubonakala ngathi ireakshini ayinakubuyela umva.

Izalamane ezisuswe amaqela emethyl zitshintsha isikali

Susa amaqela emethyl kwiingalo ezimbini zedimethylamino, size isibini sihlale sikhona kodwa sineempawu ezitshintshileyo. Eyona ndawo iphezulu yokufunxa ihamba ngokuthe ngcembe kwicala eliluhlaza okwesibhakabhaka ngokususwa ngakunye kweqela lemethyl: imethylene blue kufutshane ne-664 nm, i-Azure B kufutshane ne-654, i-Azure A kufutshane ne-630, i-Azure C kufutshane ne-615, nethionine kufutshane ne-600 nm. I-Azure B, engenalo iqela elinye lemethyl, sesona salamane sisondeleyo: yimveliso ephambili yemetabolism yemethylene blue, kunye nento engacocekanga ebhaliweyo kwimathiriyeli yemethylene blue. I-Azure A ne-Azure C ziqhubeka nolu luhlu zinesakhiwo esisiseko esifanayo esisebenzayo kwiredox. Ithionine, enamaqela omabini eamino asuswe onke amaqela emethyl, isekupheleni, inepotenshiyali esesikweni ekufutshane ne-+0.06 V kwi-pH 7 xa ithelekiswa nemethylene blue ekwi-+0.011 V, nto leyo eyenza kube lula ngakumbi ukuyinciphisa. Iipotenshiyali zeredox kulo lonke olu luhlu zixhomekeke kwindawo ekwenzeka kuyo ireakshini nakwi-electrode, ngoko thelekisa amaxabiso kuphela xa ephantsi kweemeko ezifanayo. Yiyo loo nto ukuhlalutya izinto ezingacocekanga kungumba weredox, kungengombandela nje wokuphawula ukuba imveliso icocekile. Iipesenti ezimbalwa ze-Azure B zithetha iipesenti ezimbalwa zesibini esahlukileyo seredox ebhotileni, yaye i-Azure B njengento engacocekanga nemveliso yemetabolism ichaza indlela esilawulwa ngayo eso sabelo.

Indawo engena kuyo ibhayoloji

Ngaphakathi kwiseli ebomvu yegazi, i-NADPH inciphisa imethylene blue ibe yileucomethylene blue, luze uhlobo lweleuco ludlulisele ii-elektroni kwi-iron yeheme ekwimeko ye-ferric, lubuyisele ihemoglobin kwimeko ye-ferrous. Loo ndlela yokudluliselwa kwe-elektroni sisiseko sekhemistri sokusetyenziswa kwemethylene blue kwimethemoglobinemia efunyenwe kamva. Yonke into elandela olo dluliselo, imetabolism yamandla, ukuhamba kwee-elektroni kwimitochondria, kunye nasiphi na isiphumo sebhayoloji, yeyomxholo wothutho lwee-elektroni kwimitochondria yaye ishiywe apho ngabom.

Thenga isibini, hayi umbala kuphela

Umgangatho wedayi yeredox uxhomekeke kuphela kwiimfuno zayo ezichaziweyo. Ukucoceka okuphezulu kubalulekile kuba imethylene blue engeyiyo eye-USP idla ngokuba yeyo kushishino lwamalaphu, iphethe i-Azure B, izinyithi ezinzima, okanye izinyibilikisi ezishiyekileyo ezitshintsha izilinganiso zeredox zize zenze iindawo zokuphela kwereakshini zingacaci, izinto ezingavavanywa yiyo nayiphi na inkqubo yokufaka umbala. Abathengisi abaninzi abathi bayayithobela i-USP bavavanya kuphela izinyithi ezinzima baze bavakalise ukuba baphumelele. Ukuthobela ngokupheleleyo kubandakanya ukuqinisekiswa kwesazisi, umlinganiselo wesiqulatho, izinto ezingacocekanga ze-organic, izinyibilikisi ezishiyekileyo, izinto ezingacocekanga zeziqalelo, intsalela emva kokutshiswa, imida yeentsholongwane, kunye nee-endotoxin zeebhaktiriya, yaye indlela yokukhetha imethylene blue yodidi lwamayeza ichaza indlela yokufunda loo maxwebhu. IBlupreme isebenza nomvelisi wemethylene blue yodidi lwamayeza, ivavanya zonke iimfuno ezichaziweyo ze-USP, ize ipapashe i-COA epheleleyo. Xa umbala ingumlinganiselo, loo maxwebhu ayinxalenye yesixhobo.