Nkhani
Methylene Blue ndi Vitamini C: Chifukwa Chake Madziwo Angakhale Opanda Mtundu
Mumaika piritsi la vitamini C m'galasi la madzi okhala ndi methylene blue ya buluu, kusonkhezera, n'kuona mtundu wa buluu ukuzimiririka. Pakatha miniti imodzi madziwo amaoneka ngati madzi wamba. N'zosavuta kuganiza kuti vitamini C wawononga utotowo kapena wachititsa kuti usagwirenso ntchito.
Maganizo amenewa ndi olakwika, ndipo cholakwikacho n'chofunika kuchizindikira. Zimene mukuona ndi kusintha kwa mkhalidwe wa oksideshoni komwe kungabwerere m'mbuyo, osati kuwonongeka. Utotowo udakalipo. Zinthu zikakhala zoyenera, mtundu wake umabwereranso.
Mikhalidwe iwiri ya utotowo
Methylene blue ili ndi mikhalidwe iwiri yomwe yafotokozedwa bwino. Mkhalidwe wa oksideshoni, womwe nthawi zambiri umalembedwa MB+, uli ndi dongosolo lalikulu la mphete zolumikizana mwa conjugation, lomwe limayamwa kwambiri kuwala pafupi ndi 664 nm. Kuyamwa kuwala kumeneku ndi kumene kumapereka mtundu wa buluu. Mkhalidwe wochepetsedwa, leucomethylene blue (LMB), wataya gawo limenelo la kuyamwa kwambiri kuwala kooneka, choncho madzi okhala ndi utoto wochepa amaoneka opanda mtundu.
Ganizirani utotowo ngati nkhokwe yaing'ono ya maelekitironi yomwe ingadzazidwenso. Kuuika maelekitironi ndi proton kumachotsa mtundu wake. Kuchotsamo maelekitironiwo kumabwezeretsa mtunduwo:
MB+ + H+ + 2e- to LMB (yopanda mtundu)
Vitamini C ndi amene amapereka maelekitironiwo. Ascorbate imachita oksideshoni kupita ku dehydroascorbate ndipo imapereka mphamvu yochepetsera yofanana ndi maelekitironi awiri. Choncho, powerengera momwe zingakhalire popanda zosokoneza, mole imodzi ya ascorbate imachepetsa pafupifupi mole imodzi ya MB+. M'madzi enieni a mu labotale, kuwerengeraku kumakhala kovuta chifukwa oxygen yosungunuka imapikisana kufuna maelekitironi omwewo. N'chifukwa chake nthawi zambiri pamafunika ascorbate yochulukirapo kuti madziwo akhalebe opanda mtundu.
Njirayi sikuyenera kukhala sitepe imodzi yokha yosamutsira maelekitironi awiri popanda zosokoneza. Ma radical ndi zinthu zapakati zochepetsedwa pang'ono zimatengapo mbali, ndipo njira yeniyeni imasintha malinga ndi chosungunulira, kuchuluka kwa asidi, ndi kuchuluka kwa zinthu zosungunuka. Komabe, zotsatira zomaliza zimakhala zomwezo. MB+ ya buluu imasanduka LMB yopanda mtundu, ndipo vitamini C amagwiritsidwa ntchito n'kumatha panjirayo.
Chifukwa chake kugwedeza kumabwezeretsa mtundu wa buluu
Mayesowa, monga amachitikira kawirikawiri m'kalasi, amakhala ndi gawo lachiwiri. Mukasiya kabotolo kopanda mtundu osakakhudza, kamakhalabe kopanda mtundu. Mukakagwedeza, mtundu wa buluu umabwerera. Mukadikira, umazimiririkanso.
Chobwezeretsa mtunduwo ndi oxygen. O2 yosungunuka imachititsa LMB kuchita oksideshoni kubwerera ku MB+, choncho kugwedeza sikuyambitsa utotowo kugwira ntchito. Kumawonjezera oxygen yosungunuka mwa kusakaniza mpweya wa pamwamba pa madzi ndi madziwo, ndipo zimenezi zimafulumizitsa kusintha kobwerera m'mbuyo. Ngati ascorbate yotsala idakalipo, MB+ yomwe yabwererayo imachepetsedwanso. Izi zimapereka kayendedwe kodziwika bwino: kusiya osagwedeza kumapereka madzi opanda mtundu, kugwedeza kumapereka buluu, ndipo kudikira kumaperekanso madzi opanda mtundu. Ascorbate ikatha, oxygen imapambana mokhalitsa ndipo madziwo amakhalabe a buluu.
N'chifukwa chake chionetsero cha methylene blue ndi vitamini C chimakhudzidwa ndi mawonekedwe a chidebe. Kyuveti yotsekedwa yokhala ndi malo ochepa a mpweya pamwamba pa madzi imakhalabe yopanda mtundu kwa nthawi yaitali kuposa beka yotambalala. Kulowetsamo mpweya mwamphamvu kumafupikitsa nthawi yomwe madziwo amakhala opanda mtundu. Choncho aliyense amene akufotokoza mayesowa ayenera kutchula mmene oxygen inalili, osati kuchuluka kwa zinthu zochititsira kusintha kokha.
Chionetsero choyendetsedwa mosamalitsa ndi zofunikira zake
Chithunzi choyambirira cha nkhaniyi chikusonyeza kufananitsa komwe kukufunidwa: chitsanzo cha MB+ ya buluu chosinthidwa ayi, pafupi ndi chitsanzo cha LMB chochepetsedwa ndi ascorbate, zonse zili pa kuwala kofanana. Kuti zotsatirazo zizipezekanso pobwereza mayesowo, sungani chinthu chilichonse chimene chimasintha liwiro kuti chisamasinthe:
| Chinthu chosinthika | Mkhalidwe wolangizidwa | Chifukwa chake chili chofunika |
|---|---|---|
| Methylene blue | 10 mpaka 90 micromolar mu buffer ya phosphate, pH 7 | Zimagwirizana ndi kuchuluka kogwiritsidwa ntchito m'maphunziro ofalitsidwa a redox ndipo zimasunga kuyamwa kuwala m'kati mwa muyeso wa chipangizo |
| Ascorbate | 1 mM sodium ascorbate, yokonzedwa kumene | Imapereka mphamvu yochepetsera yochulukirapo kuti mtundu uchokeretu |
| Buffer ndi pH | 50 mM phosphate, pH 7.0, kutentha kwa m'chipinda | Zimakhazikitsa mitundu ya ascorbate yomwe ilipo ndi kukhazikika kwa LMB |
| Kuwala | Kuwala kofooka kwa pamalopo, lembani nthawi yomwe zitsanzo zakhala pa kuwala | Kuwala kwamphamvu kumawonjezera njira za photoredox ndi peroxide |
| Oxygen | Kabotolo kamodzi kodzaza ndi mpweya wosungunuka, kena kochotsedwa mpweya pogwiritsa ntchito nitrogen | Kumasiyanitsa kayendedwe ka redox kopanda zosokoneza ndi oksideshoni yobwereza |
| Zitsulo | Zinthu zochititsira kusintha za mulingo wa kusanthula, komanso chitsanzo chimodzi choyerekezera chokhala ndi chomangirira zitsulo | Iron yochepa kwambiri imatsegula njira ya kemistri ya Fenton (onani pansipa) |
Jambulani zithunzi za mabotolo onse awiri pa nthawi zokhazikika, mwachitsanzo pa mphindi 0, 1, 5, ndi 15, kenako gwedezani ndi kujambulanso. Kabotolo kochotsedwa mpweya ndi nitrogen kayenera kukhala kopanda mtundu kwa nthawi yaitali kwambiri. Kabotolo kolowetsedwa mpweya kayenera kubwerera ku buluu mofulumira kwambiri kakagwedezedwa. Ngati chitsanzo sichibwereranso ku buluu ngakhale chitagwedezedwa ndi kulowetsedwa mpweya, ganizirani za kuwonongeka kosabwezeka m'malo mwa kuchepetsedwa kokha.
Okonza zosakaniza amagwiritsa ntchito mfundo yomweyi pa mlingo waukulu. Khalidwe la methylene blue m'chosakaniza limadalira zinthu zonse zokhudza redox ndi kapangidwe ka chosakanizacho. Poyesa kukhazikika, ayenera kulemba pH, oxygen yosungunuka, kuchuluka kwa kuwala komwe chitsanzo chalandira, ndi zitsulo zochepa kwambiri, pamodzi ndi zomwe aona pa mtundu.
pH, kuwala, ndi kuchuluka kwa zinthu zimakokera mbali zosiyanasiyana
Oyamba kuphunzira nthawi zambiri amafunsa ngati asidi kapena base imafulumizitsa kusinthaku. Yankho lolondola ndi lakuti pH imakhudza magawo awiri osiyanasiyana a kayendedwe kameneka. M'madzi okhala ndi asidi, kupezeka kwa ma proton kungafulumizitse sitepe ya kuchepetsedwa kwa MB+ ndi ascorbate. Koma LMB yeniyeniyo imakana kwambiri oksideshoni ya mpweya ikakhala mu asidi, ndipo imachitanso oksideshoni mofulumira kwambiri pH ikakwera. Choncho chitsanzo chokhala ndi asidi chingathe kutaya mtundu mofulumira n'kukhalabe chopanda mtundu, pamene chitsanzo cha alkaline chimataya mtundu ndi kubwerera ku buluu mofulumira. Zonsezi zimakhala zolondola m'mikhalidwe yawo.
Kuwala kumawonjezera njira ina. Methylene blue ikalandira mphamvu ya kuwala, imafika mu mkhalidwe wa triplet wokhalitsa, momwe imasamutsa maelekitironi ndi ascorbate komanso oxygen. Kemistri yoyambitsidwa ndi kuwala imeneyi ingathe kufulumizitsa kutha kwa mtundu, kubwezeretsa mtundu, kapena kupanga mitundu ya oxygen yochita kusintha mosavuta, malinga ndi kutalika kwa mafunde a kuwala, mulingo wa oxygen, ndi kuchuluka kwa zinthu. Tengani kuwala ngati chinthu chosinthika cha mayeso ndipo lembani mmene kulili.
Kuchuluka kwa zinthu kumakhazikitsa njira yomwe ipambane. Ascorbate yochuluka imatanthauza kutha kwa mtundu mofulumira komanso kubwereza kangapo kwa kugwedeza ndi kuzimiririka kwa mtundu. Utoto wochuluka umafuna mphamvu yochepetsera yochuluka molingana nawo. Oxygen yosungunuka yochuluka imalimbikitsa mtundu wa buluu. Utoto ukachuluka kwambiri, pamabwera vuto linanso chifukwa methylene blue imalumikizana yokha kukhala magulu a mamolekyulu awiri ndi magulu akuluakulu okhala ndi masipekitiramu osiyana. Choncho kuwirikiza utoto sikumawirikizanso khalidwe lomwelo.
Kodi vitamini C amachititsa methylene blue kusagwiranso ntchito?
Ili ndi funso lomwe limachititsa anthu ambiri kufufuza za methylene blue ndi vitamini C, ndipo likufunika yankho lolunjika. Ayi, kutayika kwa mtundu sikutanthauza kuti chinthucho sichikugwiranso ntchito. Chromophore yasintha mkhalidwe, koma maziko a phenothiazine ndi kuthekera kwake kochita redox zidakali m'madziwo. Kusinthako kungabwezedwe ndi mpweya, ndipo mkhalidwe wochepetsedwawo nawonso umachita kusintha ndi zinthu zina: LMB ilibe chaji ndipo imakopeka ndi mafuta kwambiri poyerekeza ndi MB+. M'maphunziro a maselo, imadutsa nembanemba isanachitenso oksideshoni mkati.
Zolemba za kafukufuku wa maselo zimasonyeza mfundoyi momveka. M'maselo a endothelium okulitsidwa mu labotale, methylene blue pa mlingo wochepa wa micromolar imalimbikitsa kugwira ntchito kwa njira ya pentose phosphate pamene ikuchititsa NADPH ndi NADH kuchita oksideshoni. Ikapitirira pafupifupi 5 micromolar, imawonjezera zizindikiro za zinthu zochititsa oksideshoni mkati mwa maselo ngati glucose yothandizira palibe. Maselo odzazidwa ndi ascorbate amachititsa ascorbateyo kuchita oksideshoni pang'onopang'ono akakumana ndi utotowo. Kuchuluka kwa ascorbate kumangochepetsa pang'ono chizindikiro cha zinthu zochititsa oksideshoni, monga zinalembedwera mu kafukufuku wa redox wa utotowo m'maselo a endothelium. Mwanjira ina, ascorbate imatengapo mbali pakusinthana kwa redox. Siimitsa utotowo kugwira ntchito.
Kuwala kumapangitsa mfundoyi kuonekera bwino kwambiri. Zikakhala pa kuwala, zosakaniza za methylene blue, ascorbate, ndi oxygen zimagwiritsa ntchito oxygen, zimaunjikitsa hydrogen peroxide, ndipo ngati pali iron yofulumizitsa kusintha, zimapanga radical ya hydroxyl kudzera mu kemistri ya Fenton. Izi zinasonyezedwa ndi mayeso a kugwira ma spin ndi kuyamwa oxygen. Ma radical a hydroxyl angawononge mamolekyulu a zamoyo mosabwezeka komanso kuwononga utotowo. Choncho chitsanzo chomwe chataya mtundu mokhalitsa chili pa kuwala ndi choipitsidwa ndi iron sichikusonyeza kuchepetsedwa kopanda zosokoneza. Chingakhale chikusonyeza kuwonongeka kochitika chifukwa cha kusintha kwina kwa kemistri.
Zimene madzi opanda mtundu satsimikizira
Mfundo zitatu zomwe anthu amakonda kuganiza zimapitirira umboni womwe ulipo, ndipo ziyenera kupewedwa m'manotsi a labotale, pamalembo a zinthu, ndi pazithunzi zophunzitsira.
Choyamba, kukhala kopanda mtundu sikutanthauza kukhala kopanda vuto. LMB pamodzi ndi oxygen ndi zitsulo zochepa kwambiri zingalimbikitse njira za peroxide ndi ma radical, makamaka pa kuwala. Kutsimikizira kuti chinthu chilibe vuto kumafuna kafukufuku wa poizoni, osati kuyeza mtundu.
Chachiwiri, kukhala kopanda mtundu sikutanthauza kuti kuipitsidwa kwachotsedwa. Utotowo ndi zinthu zomwe zimachita nawo redox zidakalipo. Zinthu zotayikira, madzi otuluka pa ntchito, ndi zipangizo zodetsedwa ndi utoto sizimayeretsedwa pongowonjezera ascorbate. Pamafunika kutsimikizira mwa kusanthula, nkhani yomwe imafotokozedwa m'njira zoyesera zotsalira ndi kuchotsa kuipitsidwa.
Chachitatu, kukhala kopanda mtundu sikukhazikitsa njira yothandiza yogwiritsira ntchito zinthu ziwirizi pamodzi. Kusintha kochitika m'chubu choyesera sikunena kanthu za kuyamwidwa m'thupi, kufalikira m'minofu, mlingo woperekedwa, kapena chitetezo cha kugwirizana kwa zinthu zimenezi mwa anthu. Aliyense amene akuganiza kuphatikiza zinthu ziwirizi pa cholinga cha thanzi ayenera kuwerenga kaye zolemba za kugwirizana kwawo ndi chitetezo, komanso kufunsa magwero oyenerera m'malo mongotengera zimene zachitika m'kabotolo.
Kutanthauzira kolondola n'kocheperapo koma n'kothandiza kwambiri. Methylene blue pamodzi ndi ascorbate ndi chitsanzo chophweka cha kayendedwe ka redox: vitamini C amapereka maelekitironi, utotowo umakhala wopanda mtundu, oxygen imatenganso maelekitironiwo, mtundu umabwerera, ndipo kuwala, pH, kuchuluka kwa zinthu, ndi iron zimakhazikitsa liwiro ndi zinthu zina zomwe zimapangidwa. Mfundo imeneyi ikamveka bwino, chionetserocho chimasiya kuoneka ngati chinyengo n'kuyamba kukhala njira yodziwira zomwe zikuchitika. Ngati chitsanzo chanu chikuchita mosiyana, yang'anani mmene oxygen ikulowera, kuchuluka kwa kuwala komwe chalandira, pH, ndi kuipitsidwa ndi zitsulo musanayambe kukayikira utotowo.