Tsom ntsoov rau Cellulose ethers

Qhov pH ntawm HPMC yog dab tsi?

HPMC (Hydroxypropyl Methylcellulose, hydroxypropyl methylcellulose) yog cov dej-soluble polymer dav siv hauv kev lag luam tshuaj, zaub mov thiab tshuaj pleev ib ce. Nws yog tsuas yog siv los ua cov thickener, stabilizer, emulsifier, film-forming agent thiab tswj tus neeg saib xyuas. Tso cov khoom siv. Nws lub ntsiab feature yog hais tias nws muaj peev xwm tsim ib tug pob tshab kua nyob rau hauv dej thiab muaj zoo thickening thiab adhesion zog.

Tus nqi pH ntawm HPMC
HPMC nws tus kheej tsis muaj tus nqi pH tas li vim nws yog cov khoom nruab nrab lossis me ntsis acidic polymer. HPMC yog ib qho nonionic cellulose derivative, yog li nws tsis cuam tshuam qhov pH ntawm cov tshuaj. Thaum yaj hauv dej, pH ntawm cov tshuaj feem ntau yog nyob ntawm pH ntawm cov kuab tshuaj nws tus kheej es tsis yog cov tshuaj lom neeg ntawm HPMC cov khoom nws tus kheej.

Feem ntau, pH ntawm HPMC cov kev daws teeb meem yuav txawv nyob ntawm qhov hnyav. Feem ntau, pH ntawm HPMC cov kev daws teeb meem hauv cov dej huv yog kwv yees li ntawm 6.0 thiab 8.0. Qhov zoo ntawm cov dej los ntawm ntau qhov chaw, nrog rau cov qib viscosity sib txawv ntawm HPMC, yuav cuam tshuam me ntsis rau pH ntawm cov tshuaj kawg. Yog tias nws tsim nyog siv HPMC cov kev daws teeb meem hauv ib qho pH tshwj xeeb, qhov no tuaj yeem hloov kho los ntawm kev ntxiv buffers thaum lub sij hawm tsim cov txheej txheem.

Cov nyhuv ntawm lub cev thiab tshuaj lom neeg ntawm HPMC ntawm pH
Txij li HPMC yog ib qho tsis-ionic compound thiab tsis muaj pawg dissociable hauv nws cov molecules, nws tsis ncaj qha cuam tshuam rau pH ntawm cov tshuaj xws li qee cov cationic lossis anionic polymers. Tus cwj pwm ntawm HPMC hauv kev daws yog feem ntau cuam tshuam los ntawm cov yam ntxwv xws li qhov kub thiab txias, concentration, thiab lub zog ionic.

Viscosity thiab kev daws teeb meem: Ib qho tseem ceeb ntawm HPMC yog nws cov viscosity, nws qhov hnyav molecular uas txiav txim siab seb nws coj li cas hauv kev daws. Lub pH ntawm cov kua dej uas tsis muaj viscosity HPMC yuav nyob ze rau cov pH ntawm cov dej nws tus kheej (feem ntau nyob ib ncig ntawm 7.0), thaum lub siab-viscosity HPMC cov tshuaj yuav zoo li me ntsis acidic los yog alkaline, nyob ntawm seb muaj impurities los yog lwm yam additives. hauv kev daws teeb meem. .

Qhov cuam tshuam ntawm qhov kub thiab txias: Lub viscosity ntawm HPMC cov kev daws teeb meem hloov nrog kub. Thaum qhov kub nce, qhov solubility ntawm HPMC nce thiab viscosity txo. Qhov kev hloov pauv no tsis cuam tshuam ncaj qha rau pH ntawm cov tshuaj, tab sis nws tuaj yeem hloov qhov fluidity thiab kev ntxhib los mos ntawm cov tshuaj.

Kev hloov pH hauv daim ntawv thov scenarios
Hauv qee cov ntawv thov tshwj xeeb, xws li kev tswj hwm kev tso tawm rau cov tshuaj lossis cov khoom noj ntxiv, tej zaum yuav muaj cov cai tshwj xeeb rau pH. Hauv cov xwm txheej no, pH ntawm HPMC cov tshuaj tuaj yeem hloov kho los ntawm kev ntxiv cov kua qaub, hauv paus, lossis tsis muaj kev daws teeb meem. Piv txwv li, citric acid, phosphate buffer, thiab lwm yam tuaj yeem siv los kho cov pH ntawm HPMC kev daws teeb meem kom muaj kev ruaj ntseg thiab kev ua tau zoo ntawm cov khoom kawg.

Rau HPMC daim ntawv thov hauv cov tshuaj formulations, pH tswj yog ib qho tseem ceeb tshwj xeeb vim hais tias cov dissolution thiab tso cov nqi ntawm cov tshuaj feem ntau nyob ntawm seb pH ntawm ib puag ncig. Qhov tsis-ionic xwm ntawm HPMC ua rau nws pom zoo tshuaj stability nyob rau hauv ib puag ncig nrog txawv pH qhov tseem ceeb, ua rau nws haum rau siv nyob rau hauv lub qhov ncauj ntsiav tshuaj, tsiav tshuaj, ophthalmic npaj thiab tshuaj pleev ib ce.

Tus nqi pH ntawm HPMC nws tus kheej tsis muaj tus nqi ruaj khov. Nws pH nyob ntawm ntau dua ntawm cov kuab tshuaj thiab cov tshuaj siv. Feem ntau, pH ntawm HPMC cov kev daws teeb meem hauv dej yog kwv yees li 6.0 txog 8.0. Hauv kev siv tswv yim, yog tias qhov pH ntawm HPMC cov tshuaj yuav tsum tau hloov kho, nws tuaj yeem hloov kho los ntawm kev ntxiv cov tshuaj tsis haum lossis kua qaub-puag.


Post lub sij hawm: Oct-18-2024
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