Kutheni ukufunxwa kokukhanya yi-methylene blue kutshintsha ngoxinaniso

Thatha ibhotile enye yesisombululo esingumthombo se-methylene blue uze ugalele kwiiglasi ezimbini. Zalisa eyokuqala ngesisombululo esingumthombo, uze eyesibini uyizalise ngesisombululo esixutywe ukuze uxinaniso lwaso lube sisinye kwishumi lolo lomthombo. Iglasi yesibini inombala okhanyayo ngakumbi, njengoko kulindelekile. Jonga ngononophelo, ubone ukuba kukho enye into etshintshileyo. Ithoni yombala itshintshile. Esinye isisombululo sithanda umbala ozuba ocacileyo wesibhakabhaka, esinye sithanda ozuba othe thsuphe ngemfusa. Ukuxuba akwenzanga nje ukunciphisa ubunzulu bombala. Kutshintshe ukuba loluphi uhlobo lwemichiza olufunxa ukukhanya kakhulu.

Ingcamango engunobangela wolu tshintsho ilula. I-methylene blue enyibilikileyo ayikho kuhlobo olunye kuphela. I-cation enye yedayi, ebizwa ngokuba yimonomer, inokubekwa ubuso ngobuso nenye i-cation ukuze zenze idimer, zize iidimer zidibane zibe ngamaqela amakhulu ngakumbi. Uhlobo ngalunye lunespektram yalo yokufunxa ukukhanya. Into eboniswa yi-spectrophotometer sisiphumo esidityanisiweyo somxube okhoyo kuloo cuvette, phantsi kwezo meko. Tshintsha umxube, itshintshe nespektram, nokuba umthamo uwonke wedayi ulandela umlinganiselo wokuxuba othe ngqo.

Imonomer nedimer zifunxa ukukhanya ngokwahlukileyo

Yiba nomfanekiso wemonomer njengekhadi elisicaba elinentlawulo yombane evumayo esasazeke kuyo yonke inkqubo yalo yezangqa. Amakhadi amabini anjalo anokubekwa ubuso ngobuso. Iintlawulo ezivumayo ziyatyhalana, kodwa imiphezulu esicaba enesakhiwo se-aromatic iyatsalana ngenxa yokudibana ngokubekwa enye phezu kwenye, yaye amanzi nee-ion ezinentlawulo echaseneyo ezingqongileyo zinciphisa ukutyhalana. Isiphumo sisibini esibambeneyo esabelana ngeemeko zee-elektroni. Utshintsho lwaso oluvumelekileyo luphakathi kweemeko ezinamandla aphezulu kunotshintsho lwemonomer, ngoko ibhendi yedimer ibonakala kubude bamaza obufutshane kunebhendi yemonomer, amaqela amakhulu wona esongeza igxalaba kwicala elizuba lespektram.

Xa uxinaniso lusezantsi kakhulu emanzini acocekileyo, iimonomer zezona zininzi, yaye ibhendi yobude bamaza obude yeyona ibalaseleyo. Njengoko uxinaniso lulonke lukhula, uhlobo oluzizibini luthatha isabelo esandayo, nebhendi yobude bamaza obufutshane ikhula xa ithelekiswa neyokuqala. Ngoko umlinganiselo wezi bhendi zimbini ubonisa ukwakheka komxube, hayi uxinaniso lulonke ngokuthe ngqo. Umlinganiselo othathwe kubude bamaza obunye awukwazi ukwahlula ezi ntlobo zimbini ngaphandle kokucingela ukuba loluphi uhlobo olukhoyo.

Yiyo loo nto iispektram zesalathiso kufuneka zisoloko zikhatshwa ziimeko zazo. Isalathiso sespektram se-methylene blue sibeka kwitheyibhile iindawo zeebhendi, kunye nesinyibilikisi, umxholo wetyuwa, i-pH, iqondo lobushushu noluhlu loxinaniso ezizivelisileyo. Chaza incopho ngaphandle kwezo meko, elo nani alichazwanga ngokwaneleyo. Iilabhoratri ezimbini zinokuba zichanile zombini ngeespektram ezahlukeneyo zedayi enye, kuba zilinganise imixube eyahlukeneyo.

Yintoni etshintsha ulungelelwaniso

Uxinaniso yeyona nto iphambili elutshintshayo. Ukwenziwa kwedimer kufuna ukuba iimonomer ezimbini zidibane, ngoko isabelo sayo sikhula ngokukhawuleza kunokwanda okuthe ngqo komthamo uwonke wedayi. Amaxabiso axeliweyo ezizinzi zolungelelwaniso lokwenziwa kweedimer emanzini akumawaka nge-molar kufuphi neqondo lobushushu begumbi, ngoko isabelo seedimer sikhula ngokukhawuleza kuluhlu lwe-micromolar. Ukulungelelaniswa kwemodeli kwidatha iyonke, ukusuka kwi-micromolar ukuya kwi-millimolar yedayi, kwafumanisa ukuba iitetramer sele zinegalelo elingenguye uziro nangaphantsi kwe-34 micromolar. Oku kusilumkisa ukuba singathembeli kwimodeli eneentlobo ezimbini kuphela xa uxinaniso lungamashumi e-micromolar. Izabelo ezichanekileyo zixhomekeke kulwelo ezikulo, yiyo loo nto eli nqaku linika indlela utshintsho oluya ngayo kunokuba linike itheyibhile yoguqulelo esebenza kuyo yonke imeko.

Ityuwa yinto yesibini elutshintshayo. Ii-ion ezinyibilikileyo zinciphisa ukutyhalana phakathi kwee-cation ezimbini, ngoko ukongeza i-sodium chloride nee-electrolyte ezifana nayo kutyhalela umxube kwiidimer nakumaqela amakhulu ngoxa uxinaniso lwedayi luhlala lunjalo. Esi siphumo siyabonakala kwizifundo zokudibana kwe-methylene blue kwizisombululo zetyuwa nasemanzini, apho idayi emalunga ne-1 micromolar ukuya kwi-3.4 millimolar yalinganiswa kwi-sodium chloride ukusuka kwi-0 ukuya kwi-0.15 molar. Kuloo modeli, isabelo seetetramer safikelela malunga ne-0.93 kwimeko enoxinaniso oluphezulu lwedayi nolwetyuwa. Ngoko ispektram erekhodwe emanzini nenye erekhodwe kwisisombululo setyuwa esihambelana nolwelo lomzimba azinakusetyenziswa njengezalathiso ezithatha indawo yesinye.

Iqondo lobushushu litsalela kwelinye icala. Ukubekwa kweemolekyuli enye phezu kwenye kukhulula amanzi abebambekile, yaye kuchaswa kukushukuma okubangelwa bubushushu. Ngoko ukufudumeza isisombululo kudla ngokwahlula ezinye iidimer zibuyele kwiimonomer, ngoxa ukupholisa kuxhasa ukudibana kwazo. I-enthalpy yokwahlukana efunyenwe ngokulungelelanisa imodeli ayivumanga, imalunga nothabatha 30 kilojoules per mole phakathi kwe-282 ukuya kwi-333 kelvin, nto leyo eqinisekisa ukuba ukudibana kukhulula ubushushu. Isampulu ebandayo elinganiswa ngoko nangoko emva kokuphuma efrijini inokubonakala inamaqela adibeneyo ngakumbi kunaloo sampulu inye ilinganiswe emva kokufikelela kulungelelwaniso neqondo lobushushu begumbi.

Isinyibilikisi sibeka imeko esisiseko. Amanzi, ngenxa yempembelelo yawo enamandla kwiindawo ezingatsalelwa ngamanzi, akhuthaza ii-cation zedayi ezisicaba ukuba zibekwe enye phezu kwenye. Ii-alcohol ezifana ne-ethanol ne-methanol zingqonga izangqa zedayi ngcono ngeemolekyuli zesinyibilikisi zize zahlule amaqela adibeneyo, ngoko uxinaniso olunye lwedayi lubonakala luneemonomer ezininzi kwi-ethanol kunasemanzini. Izinyibilikisi ezongezelelweyo ze-aprotic zenza okufanayo: kwimixube yamanzi ne-DMSO kwi-293 kelvin, i-DMSO eyongeziweyo yanciphisa ukwenziwa kweedimer, nto leyo ebonisa ukuba isakhiwo samanzi sikhuthaza ukubekwa kweemolekyuli enye phezu kwenye. Izinto ezisebenza kumphezulu wolwelo zifuna ukuqwalaselwa ngononophelo kuwo omabini amacala. Xa zingaphezu koxinaniso olubalulekileyo lokwenziwa kweemicelle, iimicelle zinokunyibilikisa iimonomer nganye ngokwayo zize zibuyisele ispektram efana neyemonomer. Ngaphantsi kwelo nqanaba, into esebenza kumphezulu enentlawulo echaseneyo inokukhuthaza ukubekwa kweemolekyuli enye phezu kwenye: kwidayi eyi-100 micromolar, ukwenziwa kweepolymer okubangelwa yi-SDS kwafikelela encotsheni kufuphi ne-4 millimolar SDS, malunga nesiqingatha senqanaba lokwenziwa kweemicelle, ngaphambi kokusasazwa ngokutsha xa umlinganiselo wale nto usebenza kumphezulu unyuka ngakumbi. Umsebenzi ngeempembelelo zesinyibilikisi sedayi neenkqubo ezicwangcisiweyo kwiispektram ze-methylene blue ubonisa indlela iimolekyuli ezikufuphi ngqo nedayi, hayi nje uxinaniso lulonke, ezimisela ngayo ngamandla iibhendi ezibonwayo.

I-pH ibaluleke ikakhulu kumanqanaba aseziphelweni. Kuluhlu olusondele kwi-pH engathathi cala olusetyenziswa kuninzi lomsebenzi waselebhu, i-methylene blue ihlala ikuhlobo lwayo oluqhelekileyo oluzuba oluyication, yaye ukudibana kweemolekyuli kuko okuchaphazela ispektram kakhulu. Iasidi enamandla okanye isiseko esinamandla, utshintsho lwe-redox oluvelisa uhlobo lwe-leuco olungenambala, okanye ukubophelela kwiiproteni namasuntswana, nganye kuzo yongeza iimeko ezingaphaya kwesibini semonomer nedimer. Xa ispektram itshintsha emva kokongeza isithinteli se-pH, jonga ukwakheka kwaso ukuze ufumane ityuwa nezinto ezibophelelayo ngaphambi kokuba ubeke yonke into kwi-pH kuphela. Isalathiso semichiza nokongezwa kweeproton sigcina le mibuzo yokuchonga iintlobo yahlukile kumbuzo wokudibana oxoxwa apha.

Kutheni umgca othe ngqo we-Beer-Lambert ugoba

Ubudlelwane be-Beer-Lambert buthi umlinganiselo wokufunxwa kokukhanya ulingana nesakhono sokufunxa siphindaphindwe ngoxinaniso siphindaphindwe ngobude bendlela yokukhanya. Ngumthetho wokubala. Ucingela ukuba izinto ezibalwayo zihlala zifana njengoko inani lazo litshintsha: uhlobo olunye olufunxa ukukhanya, ispektram engatshintshiyo, akukho tshintsho lwemichiza ngenxa yoxinaniso, ukukhanya kokuvavanya okunobude bamaza obunye, akukho kusasazeka okanye kuphinda kukhutshwe ukukhanya, nokukhanya okuhamba ngokwenene kubude bendlela obuchaziweyo.

Ukudibana kweemolekyuli kwaphula ingcinga yokuqala. Ngokwemigaqo yezibalo, ukufunxwa kokukhanya okupheleleyo kuhlala kusisiphumo esidityanisiweyo seentlobo ezikhoyo: ubude bendlela yokukhanya buphindaphindwe ngesakhono sokufunxa sohlobo ngalunye buphindaphindwe ngoxinaniso lwalo. Uhlobo ngalunye luthobela umthetho. Umxube awuwuthobeli, kuba uxinaniso lweentlobo alutshintshi ngokuthe ngqo ngokomthamo uwonke wedayi. Ngoko igophe lokulinganisa ukufunxwa kokukhanya kwibhendi yemonomer xa kuthelekiswa nomthamo uwonke wedayi liqala lithe ngqo kwinqanaba elixutywe kakhulu, lize ligobele ezantsi njengoko uxinaniso lukhula, kuba ukongezwa ngakunye kuzisa isabelo esincinci semonomer. Igophe elifundwa kwibhendi yedimer ligobela kwelinye icala. Umsebenzi ophanda ukudibana kweemolekyuli uchonga le nkqubo kanye njengomthombo wokutenxa okubonwayo kumthetho we-Lambert-Beer. Ukulungelelanisa umgca othe ngqo kummandla ogobileyo uze uwandise ngaphaya kwawo yimpazamo eqhelekileyo. Umgca usebenza kuphela kuluhlu nakumxube osisiseko owakhiwe kuwo.

Ukuxuba kudala umgibe ofanayo. Ukuxuba isisombululo esingumthombo esinoxinaniso oluphezulu ukuze sifike kuluhlu lwesixhobo akuwugcini umlinganiselo weentlobo. Isisombululo esixutywe kwi-cuvette siphinda sifikelele kulungelelwaniso oluthanda imonomer, ngoko ispektram yaso ichaza ngokuchanekileyo isampulu exutywe kakhulu, kodwa iyichaza ngokungachanekanga leyo ingumthombo. Ukubala ispektram yomthombo ngokunyusa amaxabiso okufunxwa kokukhanya ngokomlinganiselo wokuxuba kubuyisela uqikelelo lomthamo uwonke kuphela xa ukulinganisa sele kuthathela ingqalelo olo tshintsho. Akubuyiseli imilo yebhendi yokuqala. Nabani na othelekisa ispektram yesisombululo esinoxinaniso oluphezulu nesalathiso esixutywe kakhulu uthelekisa imixube emibini eyahlukeneyo.

Ubude bendlela yokukhanya buyinxalenye yesiphumo

Umlinganiselo wokufunxwa kokukhanya uyanda ngokomgama ukukhanya okuwuhambayo kwisampulu. I-cuvette eyi-10 mm inika ukufunxwa kokukhanya okuphindwe kalishumi kunokwe-cuvette eyi-1 mm enesisombululo esifanayo. Olo lwalamano luchaneka kuphela xa isisombululo sifana, yaye ukudibana kweemolekyuli kwenza loo mqathango ubaluleke kakhulu.

Emsebenzini, ubude bendlela yokukhanya sisixhobo sokuhlala kuluhlu olusebenzayo. Indlela ende inika uvakalelo kwizisombululo ezixutywe kakhulu, ubukhulu becala ezineemonomer. Indlela emfutshane igcina isampulu enoxinaniso oluphezulu kuluhlu lokulinganisa ngaphandle kwenyathelo elikhulu lokuxuba elinokutshintsha ulungelelwaniso. Inkqubo yokuphanda ukudibana kweemolekyuli evelise amanani angasentla yenze kanye oku: iiseli eziyi-1 centimeter kwidayi eyi-1.1 ukuya kwi-34 micromolar, neeseli eziyi-0.01 centimeter kwi-94 micromolar ukuya kwi-3.4 millimolar. Izixhaso zokulinganisa imithamo emincinci nezifundi zeepleyiti zongeza ezazo iimilo, ezineendlela ezimfutshane nezithi ngamanye amaxesha zitshintshe, kwakunye nemiphezulu enokubambelela kuyo idayi eyication. Chaza ubude bendlela kunye nenani, njengoko isalathiso sespektram sichaza isinyibilikisi netyuwa. Umlinganiselo wokufunxwa kokukhanya ongenabude bendlela yokukhanya awusosiphumo. Ngamarhe.

Ulandelelwano oluchanekileyo lokulinganisa luvela kule nkqubo. Yenza iisampulu zifikelele kulungelelwaniso kwiqondo lobushushu elinye ngaphambi kokuzifunda. Sebenzisa uhlobo olunye lwe-cuvette kwaye uyibeke ngendlela efanayo, iisampulu ezingenadayi ezihambelanayo ezinetyuwa nesithinteli se-pH ezifanayo, kunye nezixhobo zeglasi ezicocekileyo, kuba i-methylene blue ibambelela kwiglasi nakwiplastiki, yaye i-cuvette enamabala igcina umkhondo wesampulu yokugqibela eyayinoxinaniso oluphezulu. Funda ngokukhawuleza emva kokulungiselela xa isantya sokudibana kweemolekyuli sibalulekile, uze wakhe igophe ngalinye lokulinganisa kumxube osisiseko ofanayo nakubude bendlela yokukhanya obufanayo nobeesampulu ezingaziwayo. Xa ujonga ngamehlo, khumbula ukuba iliso alisiso isixhobo esilungileyo sokulinganisa ispektram. Umbuzo wokuba umbala wesisombululo unokuqinisekisa ukucoceka kwaso ngowahlukileyo, onempendulo enguhayi, yaye ukutshintsha kwethoni yombala ngenxa yokudibana kweemolekyuli sesinye sezizathu.

Umzobo wokugcina ecaleni kwesixhobo

Umzobo ongezantsi ushwankathela eli nqaku ube sisalathiso esinye setafile yokusebenza. Izisombululo ezithathu zinedayi efanayo kodwa ziyahluka ngoxinaniso lulonke nangomxholo wetyuwa. Iispektram zazo eziyimizobo zibonisa ibhendi yemonomer yobude bamaza obude iphulukana nesabelo sayo, esithathwa yibhendi yedimer yobude bamaza obufutshane njengoko ukubekwa kweemolekyuli enye phezu kwenye kusanda. Iimeko zishicilelwe kumzobo kuba ngaphandle kwazo amagophe akanakuphinda asetyenziswe. Ukufumana iindawo zeebhendi ezilinganisiweyo phantsi kweemeko ezichaziweyo, sebenzisa isalathiso sespektram. Ukuze wazi ukuba idayi ingena njani kwiiseli xa sele ikwisisombululo, jonga ukungena kwiiseli ngokuncitshiswa nokwahlulwa phakathi kweendawo. Ukuze wazi ukuba isixa sokukhanya nokwakheka kwendawo yokulinganisa kuzichaphazela njani ngakumbi iziphumo zemichiza ebangelwa kukukhanya, jonga ukuchanabeka ekukhanyeni nokwakheka kwendawo yokulinganisa.

Umgaqo omele ukhunjulwe uneenxalenye ezimbini. Ispektram ichonga umxube okhoyo kwi-cuvette phantsi kweemeko ezichaziweyo. Kuphela ukulinganisa okwakhiwe phantsi kwezo meko zinye okunokuguqula umlinganiselo wokufunxwa kokukhanya ube luxinaniso lulonke.