Qhov sib txawv tseem ceeb ntawm ODS thiab BDS kem yog ODS kem muaj cov pab pawg ua haujlwm pub dawb -OH, whereas BDS kem muaj deactivated -OH pawg.
Rov qab-theem HPLC yog cov txheej txheem chromatographic uas peb siv cov theem hydrophobic nyob ruaj khov. Qhov chaw nyob ruaj khov no ua haujlwm zoo rau kev khaws cia ntawm feem ntau cov organic analytes. Lub xov tooj ntawm tes ntawm theem rov qab HPLC yog polar. Muaj ntau hom kab uas siv rau cov txheej txheem chromatographic no. ODS thiab BDS yog ob kab ntawv.
ODS Kem yog dab tsi?
ODS kem yog hom rov qab-theem HPLC kem uas muaj cov pab pawg ua haujlwm pub dawb -OH. Nws kuj tseem hu ua C18 kem vim nws muaj octadecasilane chains. Qhov no txhais tau hais tias peb tuaj yeem sau rau C18 kem nrog ntim ntawm octadecysilyl pawg (cov no tseem muaj npe hu ua ODS pawg lossis C18 pawg) uas muaj tshuaj sib xyaw ua ke rau silica gel carrier. Cov kab ODS no tshwj xeeb yog siv rau cov txheej txheem rov qab-theem chromatographic. Cov kab no muaj tus lej theoretical siab thiab tseem qhia qhov sib npaug nrawm. Txij li cov kab no tsuas yog xav tau tus nqi qis rau kev khiav lag luam, lawv feem ntau siv nyob rau hauv reverse-theem chromatography.
Txawm li cas los xij, muaj ntau qhov tsis zoo ntawm kev siv cov kab ODS no hauv chromatography. Piv txwv li, tag nrho elution yog nrawm heev, yog li nws nyuaj rau cais qee cov khoom sib xyaw ua ke, thiab kev ruaj khov ntawm kab yuav siv sij hawm ntev sib piv.
Daim duab 01: HPLC Kem
Thaum xav txog cov qauv tshuaj ntawm ODS kem, nws muaj cov pab pawg hydroxyl (-OH) txuas rau saum npoo ntawm silica gel carrier qhov twg nws muaj cov qauv Si-OH. Cov qauv no hu ua "silanol". Hauv ODS kem packing, kev ntim khoom yog ua los ntawm kev sib txuas cov pab pawg ODS rau cov silanol los ntawm cov tshuaj tiv thaiv. Cov pab pawg ODS no loj heev, thiab lawv tsis muaj zog heev. Yog li ntawd, muaj ntau yam tsis muaj kev cuam tshuam silanol pawg nyob rau hauv kab ntawv no. Txawm li cas los xij, cov silanol dawb no tuaj yeem ua rau muaj kev ua yuam kev thaum lub sijhawm tshuaj ntsuam, yog li peb yuav tsum tau ntim cov pab pawg no nrog qee qhov sib txuas xws li TMS (trimethylsilyl) pawg uas tsis loj heev tab sis muaj zog heev. Cov txheej txheem no hu ua qhov kawg-capping.
BDS Kem yog dab tsi?
BDS kem yog hom rov qab-theem HPLC kem uas tau thaiv -OH pawg. Qhov no txhais tau tias cov pab pawg hydroxyl nyob rau hauv kab no yog deactivated / tsis pub dawb. Nws tseem muaj npe hu ua BDS C18 kem, thiab kem no tau ntim nrog octadecasilane chains. Lub sij hawm BDS sawv cev rau Base Deactivated Silica. Yog li ntawd, cov kab ntawv no kuj muaj npe hu ua kab ntawv kawg.
kab ntawv no tseem ceeb heev hauv chromatography vim nws muaj nws cov seem silanol pawg deactivated los ntawm capping. Yog li, muaj tsawg kawg nkaus residual silanol ua haujlwm. Tsis tas li ntawd, kab lus no tshwj xeeb rau kev txheeb xyuas cov ntsiab lus sib xyaw. Ntawm no, cov hauv paus muaj kev cuam tshuam nrog Si-OH pawg hauv silica packing. BDS txhua kab yog tsim los txo qhov ncov tailing, uas yog ib qho teeb meem loj hauv chromatography (tsis tuaj yeem paub txog qee qhov ncov).
Qhov txawv ntawm ODS thiab BDS Kab yog dab tsi?
ODS thiab BDS yog ob kab uas siv rau rov qab-theem chromatography. Qhov sib txawv tseem ceeb ntawm ODS thiab BDS kem yog ODS kem muaj cov pab pawg ua haujlwm pub dawb -OH, thaum BDS kem muaj cov pab pawg tsis ua haujlwm -OH. Ntxiv mus, ODS txhua kab muaj qhov siab siab tailing thaum BDS kem tsim los txo qis qhov siab kawg.
Cov lus hauv qab no qhia txog qhov sib txawv ntawm ODS thiab BDS kem.
Summary – ODS vs BDS Kem
ODS thiab BDS yog ob kab uas siv rau theem rov qab HPLC. Qhov sib txawv tseem ceeb ntawm ODS thiab BDS kem yog ODS kem muaj cov pab pawg ua haujlwm pub dawb -OH, whereas BDS kem muaj deactivated -OH pawg.
