Hydroxypropyl methylcellulose, feem ntau hu ua HPMC, yog siv dav siv tshuaj thiab khoom noj khoom haus ntxiv. Vim nws zoo heev solubility, binding peev xwm thiab film-forming zog, nws tau dav siv nyob rau hauv kev lag luam tshuaj. HPMC kuj tseem siv nyob rau hauv kev lag luam khoom noj khoom haus ua cov thickener, emulsifier thiab stabilizer. Lub purity ntawm HPMC yog qhov tseem ceeb hauv kev lag luam tshuaj thiab zaub mov vim nws cuam tshuam rau kev ua tau zoo thiab kev nyab xeeb ntawm cov khoom. Kab lus no yuav tham txog kev txiav txim siab ntawm HPMC purity thiab nws txoj hauv kev.
HPMCs yog dab tsi?
Hydroxypropylmethylcellulose (HPMC) yog cellulose ether muab los ntawm methylcellulose. Nws qhov hnyav molecular yog 10,000 txog 1,000,000 Daltons, thiab nws yog cov hmoov dawb los yog dawb dawb, tsis muaj ntxhiab thiab tsis qab. HPMC yog yooj yim soluble nyob rau hauv dej, thiab kuj soluble nyob rau hauv ib co organic solvents xws li ethanol, butanol, thiab chloroform. Nws muaj qee yam khoom tshwj xeeb xws li dej tuav, thickening thiab khi muaj peev xwm, uas ua rau nws zoo tagnrho rau kev lag luam tshuaj thiab zaub mov.
Kev txiav txim siab ntawm HPMC purity
Lub purity ntawm HPMC nyob ntawm ntau yam xws li kev hloov pauv (DS), cov ntsiab lus noo noo thiab cov hmoov tshauv. DS sawv cev rau cov pawg hydroxyl hloov los ntawm pawg hydroxypropyl hauv cellulose molecule. Kev hloov pauv qib siab ua rau muaj kev solubility ntawm HPMC thiab txhim kho lub peev xwm ua yeeb yaj kiab. Hloov pauv, qhov qis qis ntawm kev hloov pauv yuav ua rau txo qis solubility thiab ua rau cov yeeb yaj kiab tsis zoo.
HPMC Purity Determination Method
Muaj ntau ntau txoj hauv kev los txiav txim siab qhov purity ntawm HPMC, suav nrog acid-base titration, elemental tsom, high-performance kua chromatography (HPLC), thiab infrared spectroscopy (IR). Nov yog cov ntsiab lus rau txhua txoj kev:
acid-base titration
Cov txheej txheem yog ua raws li cov tshuaj tiv thaiv nruab nrab ntawm cov kua qaub thiab cov pab pawg hauv paus hauv HPMC. Ua ntej, HPMC yog yaj nyob rau hauv ib tug hnyav thiab ib tug paub ntim ntawm cov kua qaub los yog lub hauv paus tov ntawm paub concentration yog ntxiv. Titration tau ua tiav kom txog thaum pH mus txog qhov nruab nrab. Los ntawm tus nqi ntawm cov kua qaub los yog lub hauv paus noj, qhov degree ntawm kev hloov pauv tuaj yeem suav tau.
Elemental tsom xam
Elemental tsom xam ntsuas qhov feem pua ntawm txhua lub ntsiab lus tam sim no hauv cov qauv, suav nrog carbon, hydrogen, thiab oxygen. Qhov degree ntawm kev hloov pauv tuaj yeem suav los ntawm tus nqi ntawm txhua lub ntsiab lus tam sim no hauv HPMC tus qauv.
High Performance Liquid Chromatography (HPLC)
HPLC yog cov txheej txheem kev tshuaj xyuas dav siv uas cais cov khoom sib xyaw ua ke raws li lawv cov kev cuam tshuam nrog cov theem nyob ruaj khov thiab txawb. Hauv HPMC, qib ntawm kev hloov pauv tuaj yeem suav los ntawm kev ntsuas qhov piv ntawm hydroxypropyl rau methyl pawg hauv cov qauv.
Infrared Spectroscopy (IR)
Infrared spectroscopy yog ib qho kev tshuaj ntsuam xyuas uas ntsuas qhov nqus los yog kis ntawm cov hluav taws xob infrared los ntawm cov qauv. HPMC muaj qhov sib txawv qhov siab tshaj plaws rau hydroxyl, methyl thiab hydroxypropyl, uas tuaj yeem siv los txiav txim siab qhov kev hloov pauv.
Lub purity ntawm HPMC yog qhov tseem ceeb hauv kev lag luam tshuaj thiab zaub mov, thiab nws qhov kev txiav txim siab yog qhov tseem ceeb los xyuas kom meej qhov kev nyab xeeb thiab kev ua tau zoo ntawm cov khoom kawg. Muaj ntau txoj hauv kev los txiav txim siab qhov purity ntawm HPMC, suav nrog acid-base titration, elemental analysis, HPLC, thiab IR. Txhua txoj kev muaj nws qhov zoo thiab qhov tsis zoo thiab tuaj yeem xaiv tau raws li cov kev cai tshwj xeeb ntawm daim ntawv thov. Yuav kom tswj tau qhov purity ntawm HPMC, nws yuav tsum tau muab cia rau hauv qhov chaw qhuav, txias kom deb ntawm tshav ntuj thiab lwm yam kab mob.
Post lub sij hawm: Aug-25-2023