Hydroxypropyl methylcellulose, feem ntau hu ua HPMC, yog ib qho tshuaj siv dav dav thiab cov khoom noj khoom haus ntxiv. Vim nws cov solubility zoo heev, muaj peev xwm khi thiab cov khoom ua zaj duab xis, nws tau siv dav hauv kev lag luam tshuaj. HPMC kuj tseem siv dav hauv kev lag luam zaub mov ua cov khoom ua kom tuab, emulsifier thiab stabilizer. Qhov huv ntawm HPMC yog qhov tseem ceeb heev hauv kev lag luam tshuaj thiab zaub mov vim nws cuam tshuam rau kev ua haujlwm zoo thiab kev nyab xeeb ntawm cov khoom. Tsab xov xwm no yuav tham txog kev txiav txim siab ntawm HPMC purity thiab nws cov txheej txheem.
HPMCs yog dab tsi?
Hydroxypropylmethylcellulose (HPMC) yog ib qho cellulose ether uas tau los ntawm methylcellulose. Nws qhov hnyav molecular yog 10,000 txog 1,000,000 Daltons, thiab nws yog hmoov dawb lossis dawb tawm, tsis muaj ntxhiab thiab tsis qab. HPMC yooj yim yaj hauv dej, thiab kuj yaj hauv qee cov organic solvents xws li ethanol, butanol, thiab chloroform. Nws muaj qee yam khoom tshwj xeeb xws li kev khaws dej, thickening thiab binding muaj peev xwm, uas ua rau nws zoo tagnrho rau kev lag luam tshuaj thiab zaub mov.
Kev txiav txim siab ntawm HPMC purity
Qhov huv ntawm HPMC nyob ntawm ntau yam xws li qib kev hloov pauv (DS), cov dej noo thiab cov tshauv. DS sawv cev rau tus lej ntawm cov pab pawg hydroxyl hloov los ntawm cov pab pawg hydroxypropyl hauv cov cellulose molecule. Qib siab ntawm kev hloov pauv ua rau muaj kev yaj ntawm HPMC thiab txhim kho lub peev xwm tsim zaj duab xis. Ntawm qhov tod tes, qib qis ntawm kev hloov pauv yuav ua rau muaj kev yaj tsawg dua thiab cov khoom tsim zaj duab xis tsis zoo.
Txoj Kev Txheeb Xyuas Kev Huv Huv HPMC
Muaj ntau txoj kev los txiav txim siab qhov huv ntawm HPMC, suav nrog acid-base titration, elemental analysis, high-performance liquid chromatography (HPLC), thiab infrared spectroscopy (IR). Nov yog cov ntsiab lus rau txhua txoj kev:
kev ntsuas acid-base
Txoj kev no yog raws li kev ua kom tsis muaj zog ntawm cov pab pawg acidic thiab cov pab pawg basic hauv HPMC. Ua ntej, HPMC raug yaj rau hauv cov kuab tshuaj thiab ntxiv ib qho ntim ntawm cov kua qaub lossis cov kua qaub uas paub tias muaj concentration. Kev ntsuas tau ua tiav kom txog thaum pH mus txog qhov nruab nrab. Los ntawm qhov ntau ntawm cov kua qaub lossis cov kua qaub uas siv, qib kev hloov pauv tuaj yeem suav tau.
Kev tshuaj xyuas cov ntsiab lus
Kev tshuaj xyuas cov khoom ntsuas feem pua ntawm txhua yam khoom uas muaj nyob hauv cov qauv, suav nrog carbon, hydrogen, thiab oxygen. Qib ntawm kev hloov pauv tuaj yeem suav los ntawm qhov ntau ntawm txhua yam khoom uas muaj nyob hauv cov qauv HPMC.
Kev Ua Haujlwm Siab Chromatography Kua (HPLC)
HPLC yog ib txoj kev siv dav dav los tshuaj xyuas uas cais cov khoom sib xyaw raws li lawv qhov kev sib cuam tshuam nrog cov theem ruaj khov thiab cov theem txawb. Hauv HPMC, qib kev hloov pauv tuaj yeem suav los ntawm kev ntsuas qhov piv ntawm hydroxypropyl rau methyl pawg hauv cov qauv.
Kev Tshawb Fawb Txog Infrared (IR)
Infrared spectroscopy yog ib txoj kev ntsuas uas ntsuas qhov nqus lossis kis ntawm infrared hluav taws xob los ntawm cov qauv. HPMC muaj ntau qhov nqus siab rau hydroxyl, methyl thiab hydroxypropyl, uas tuaj yeem siv los txiav txim siab qib ntawm kev hloov pauv.
Qhov huv ntawm HPMC yog qhov tseem ceeb hauv kev lag luam tshuaj thiab khoom noj, thiab nws qhov kev txiav txim siab yog qhov tseem ceeb kom ntseeg tau tias muaj kev nyab xeeb thiab ua tau zoo ntawm cov khoom kawg. Muaj ntau txoj hauv kev los txiav txim siab qhov huv ntawm HPMC, suav nrog acid-base titration, elemental analysis, HPLC, thiab IR. Txhua txoj kev muaj nws tus kheej qhov zoo thiab qhov tsis zoo thiab tuaj yeem xaiv raws li qhov yuav tsum tau ua ntawm daim ntawv thov. Txhawm rau kom tswj tau qhov huv ntawm HPMC, nws yuav tsum khaws cia rau hauv qhov chaw qhuav, txias kom deb ntawm tshav ntuj thiab lwm yam khoom paug.
Lub sijhawm tshaj tawm: Lub Yim Hli-25-2023