Qhov sib txawv tseem ceeb ntawm BCA thiab Bradford assay yog qhov kev xeem BCA yog siv sijhawm thiab tsawg dua, qhov kev xeem Bradford yog qhov nrawm thiab raug.
BCA thiab Bradford assay yog ob txoj kev ntsuas kev txiav txim siab protein ntau. Ob qhov kev ntsuam xyuas no muaj cov ntsiab cai sib txawv ntawm kev ntsuam xyuas thiab qhov sib txawv ntawm lawv qhov raug.
BCA Assay yog dab tsi?
BCA assay lossis bicinchoninic acid assay yog ib qho kev kuaj biochemical muaj txiaj ntsig hauv kev txiav txim siab tag nrho cov ntsiab lus ntawm cov protein hauv kev daws teeb meem. Txoj kev no tseem muaj npe hu ua Smith assay tom qab nws tus neeg tsim khoom, Paul K. Smith. Txoj kev tshuaj ntsuam no qhia tau hais tias zoo sib xws rau Lowry protein assay, Bradford protein assay lossis biuret reagent. Peb tuaj yeem soj ntsuam tag nrho cov protein ntau hauv cov qauv muab los ntawm kev hloov xim ntawm cov qauv tshuaj, uas mus ntawm ntsuab mus rau ntshav. Qhov kev hloov xim no tshwm sim hauv kev faib ua feem ntawm cov ntsiab lus protein. Tom qab ntawd peb tuaj yeem siv cov txheej txheem colourimetric los tshuaj xyuas cov xim siv thiab cov ntsiab lus protein hauv cov qauv.
BCA Kev kwv yees Protein
Thaum xav txog cov txheej txheem ntawm kev ntsuam xyuas BCA, cov tshuaj BCA ib txwm muaj cov tshuaj alkaline heev nrog pH ntawm ze li ntawm 11.25, thiab cov khoom xyaw hauv cov tshuaj no suav nrog bicinchoninic acid, sodium carbonate, sodium bicarbonate, sodium tartrate, thiab tooj liab (II) sulfate pentahydrate. Qhov kev ntsuam xyuas no feem ntau yog nyob ntawm ob qho tshuaj tiv thaiv: qhov txo qis ntawm tooj liab (II) rau tooj liab (I) los ntawm peptide bonds hauv cov protein thiab chelation ntawm ob lub molecules ntawm bicinchoninic acid nrog tooj liab (I) ion, uas ua rau muaj cov xim liab dawb uas muaj peev xwm ua tau. nqus lub teeb ntawm 562 nm wavelength. Hauv thawj cov tshuaj tiv thaiv, tus nqi ntawm tooj liab (II) txo los ntawm peptide bonds yog proportional rau tus nqi ntawm cov protein nyob rau hauv cov qauv.
Bradford Assay yog dab tsi?
Bradford assay yog ib txoj hauv kev spectroscopic analytical muaj txiaj ntsig hauv kev ntsuas qhov concentration ntawm cov protein hauv cov tshuaj. Txoj kev no tau tsim los ntawm Marion M. Bradford xyoo 1976, thiab nws yog ib txoj kev sib piv ceev thiab raug.
Xim Cov Tshuaj Tiv Thaiv Protein thiab Bradford Reagent
Peb tuaj yeem siv txoj kev no los txiav txim siab qhov concentration ntawm cov protein ntau hauv cov qauv. Cov tshuaj tiv thaiv tshuaj uas tshwm sim hauv cov qauv thaum qhov kev ntsuam xyuas no tsuas yog nyob ntawm cov amino acid muaj pes tsawg leeg ntawm cov protein hauv cov qauv.
Bradford Method of Protein Estimation
Thaum xav txog cov qauv ntawm qhov kev ntsuam xyuas no, nws yog ib qho kev ntsuam xyuas colourimetric protein uas yog raws li kev hloov pauv ntawm cov xim muaj npe Coomassie Brilliant Blue G-250. Feem ntau, cov xim no muaj nyob rau hauv peb daim ntawv ua anionic (xiav) daim ntawv, nruab nrab (ntsuab) daim ntawv thiab cationic (liab) daim ntawv. Yog li ntawd, nyob rau hauv acidic tej yam kev mob, cov xim hloov nws cov xim ntawm liab mus rau xiav. Qhov no yog vim muaj kev sib txuas ntawm cov protein nrog cov xim. Hauv qhov sib piv, yog tias tsis muaj cov protein los khi nrog cov dye, cov xim hloov tsis tshwm, cov tshuaj tau txais xim liab-xim av. Cov xim no muaj peev xwm tsim kom muaj zog, tsis muaj qhov sib txuam nrog cov carboxyl pawg ntawm cov protein los ntawm Van der Waal rog thiab electrostatic attractions.
Qhov txawv ntawm BCA thiab Bradford Assay yog dab tsi?
BCA thiab Bradford assay yog ob txoj kev ntsuas kev txiav txim siab protein ntau. Ob qhov kev ntsuam xyuas no muaj cov ntsiab cai sib txawv ntawm kev ntsuam xyuas thiab qhov sib txawv ntawm lawv qhov raug. Qhov sib txawv tseem ceeb ntawm BCA thiab Bradford kev ntsuam xyuas yog qhov kev xeem BCA yog siv sijhawm thiab tsis raug, qhov kev xeem Bradford yog qhov nrawm thiab raug.
Cov lus qhia hauv qab no qhia txog qhov sib txawv ntawm BCA thiab Bradford kev soj ntsuam hauv daim ntawv teev npe.
Summary – BCA vs Bradford Assay
BCA assay lossis bicinchoninic acid assay yog ib qho kev kuaj biochemical muaj txiaj ntsig hauv kev txiav txim siab tag nrho cov ntsiab lus ntawm cov protein hauv kev daws teeb meem. Bradford assay yog ib txoj hauv kev spectroscopic analytical muaj txiaj ntsig hauv kev ntsuas qhov concentration ntawm cov protein hauv kev daws teeb meem. Qhov sib txawv tseem ceeb ntawm BCA thiab Bradford kev soj ntsuam yog tias BCA siv sijhawm thiab tsis raug, qhov kev xeem Bradford yog qhov nrawm thiab raug.
