Qhov sib txawv tseem ceeb ntawm isocratic thiab gradient elution yog tias isocratic elution yog hais txog kev tswj hwm qhov kev xav tsis tu ncua hauv theem mobile, whereas gradient elution yog hais txog kev tswj hwm qhov sib txawv hauv theem mobile.
Cov ntsiab lus isocratic thiab gradient elution yog siv hauv chromatography. Thaum lub sijhawm chromatographic khiav, peb siv lub sijhawm nyob ruaj khov, uas yog cov khoom tsis txav mus los, nrog rau theem mobile, cov khoom txav. Qhov isocratic thiab gradient elution piav qhia txog cov khoom ntawm lub sijhawm txawb.
Isocratic Elution yog dab tsi?
Isocratic elution yog ib lo lus siv nyob rau hauv chromatography thaum lub sij hawm mobile muaj qhov concentration tas li. Ntawm no, qhov concentration ntawm theem mobile yog tas li thoob plaws hauv cov txheej txheem chromatographic. Hauv cov txheej txheem no, peb tuaj yeem soj ntsuam qhov dav dav nce nrog lub sijhawm khaws cia linearly hauv chromatogram. Txawm li cas los xij, qhov no ua rau muaj qhov tsis zoo - qhov kawg-eluting peaks rau lig elution tau zoo heev thiab dav. Yog li ntawd, cov peaks dav no dhau los ua nyuaj rau kev lees paub tias yog peaks.
Ntxiv mus, hauv isocratic elution, qhov kev xaiv tsis hloov raws li kab ntawv qhov ntev. Qhov no txhais tau tias qhov kev xaiv tsis nyob ntawm qhov kev hloov pauv hauv kab qhov ntev. Ntawm no, qhov ntev thiab txoj kab uas hla yog suav tias yog kab qhov ntev. Yog li ntawd, lub ncov elute nyob rau hauv tib txoj kev.
Gradient Elution yog dab tsi?
Gradient elution yog ib lo lus siv nyob rau hauv chromatography thaum ntawm no theem mobile muaj qhov sib txawv. Nyob rau hauv lwm yam lus, lub concentration ntawm lub mobile theem tsis tas yuav nyob twj ywm. Piv txwv li, hauv HPLC, ib txoj kev sib cais feem ntau siv methanol 10% pib thiab xaus ntawm 90%, los ntawm kev ua kom cov concentration maj mam. Lub sij hawm mobile muaj ob yam: ib qho hnyav hnyav thiab hnyav hnyav. Cov kuab tshuaj tsis muaj zog tso cai rau cov kuab tshuaj mus rau elute maj mam thaum cov kuab tshuaj muaj zog ua rau lub elution sai ntawm cov kuab tshuaj. Nyob rau theem rov qab chromatography, peb siv dej ua cov kuab tshuaj tsis muaj zog thiab cov kuab tshuaj organic ua cov kuab tshuaj muaj zog.
Daim duab 01: HPLC
Ntxiv mus, txoj kev gradient elution txo qis tom qab eluting Cheebtsam kom lawv elute sai dua, muab lub ncov nqaim hauv chromatogram. Txoj kev no txhim kho lub ncov zoo thiab lub ncov siab ib yam nkaus. Tsis tas li ntawd, nyob rau hauv cov txheej txheem gradient elution, qhov kev txiav txim elution hloov nrog cov kev hloov hauv kab qhov ntev.
Qhov txawv ntawm Isocratic thiab Gradient Elution yog dab tsi?
Cov ntsiab lus isocratic thiab gradient elution yog siv hauv chromatography. Isocratic thiab gradient elution piav qhia txog cov khoom ntawm lub sijhawm txawb. Qhov sib txawv tseem ceeb ntawm isocratic thiab gradient elution yog tias isocratic elution yog hais txog kev saib xyuas ntawm qhov tsis tu ncua nyob rau hauv theem mobile whereas gradient elution yog hais txog kev saib xyuas ntawm qhov sib txawv ntawm cov theem mobile.
Nyob rau hauv cov txheej txheem isocratic elution, lub ncov dav nce nrog lub sij hawm tuav linearly. Txawm li cas los xij, nyob rau hauv cov txheej txheem gradient elution, qhov khaws cia ntawm cov khoom tom qab-eluting yog txo, yog li ntawd cov elution ua sai dua thiab muab nqaim peaks. Tsis tas li ntawd, nyob rau hauv isocratic elution, selectivity tsis nyob ntawm qhov ntev ntawm kab, tab sis nyob rau hauv gradient elution, lub selectivity hloov nrog hloov kab qhov ntev.
Cov lus hauv qab no qhia txog qhov sib txawv ntawm isocratic thiab gradient elution.
Summary – Isocratic vs Gradient Elution
Isocratic elution thiab gradient elution piav qhia cov khoom ntawm lub sijhawm txawb. Qhov sib txawv tseem ceeb ntawm isocratic thiab gradient elution yog tias isocratic elution yog hais txog kev saib xyuas ntawm qhov tsis tu ncua nyob rau hauv theem mobile whereas gradient elution yog hais txog kev saib xyuas ntawm qhov sib txawv ntawm cov theem mobile.
