Pa zomwe pH ndi HPMC sungunuka

Hydroxypropyl methylcellulose (HPMC)ndi polima yomwe imagwiritsidwa ntchito kwambiri muzamankhwala, zodzoladzola, ndi zakudya. Kusungunuka kwake kumadalira zinthu zosiyanasiyana, kuphatikizapo pH. Nthawi zambiri, HPMC imasungunuka muzinthu zonse za acidic ndi zamchere, koma kusungunuka kwake kumatha kusiyanasiyana kutengera kuchuluka kwa m'malo (DS) ndi kulemera kwa maselo (MW) a polima.

Mu zinthu acidic, HPMC ambiri amasonyeza solubility wabwino chifukwa protonation ake hydroxyl magulu, amene timapitiriza hydration ndi dispersibility. Kusungunuka kwa HPMC kumawonjezeka pamene pH imatsika pansi pa pKa yake, yomwe ili pafupi ndi 3.5-4.5 kutengera kuchuluka kwa kulowetsedwa.

Mosiyana ndi izi, mumikhalidwe yamchere, HPMC imathanso kusungunuka, makamaka pamtengo wapamwamba wa pH. Pa pH ya alkaline, kuchepa kwa magulu a hydroxyl kumachitika, zomwe zimapangitsa kuti kusungunuka kwa hydrogen kumangiridwe ndi mamolekyu amadzi.

Komabe, ndikofunikira kudziwa kuti pH yeniyeni yomwe HPMC imasungunuka imatha kusiyanasiyana kutengera mtundu wa HPMC, kuchuluka kwake m'malo, komanso kulemera kwake. Nthawi zambiri, magiredi a HPMC okhala ndi ma degree apamwamba olowa m'malo ndi zolemetsa zochepa zamamolekyu amawonetsa kusungunuka kwabwinoko pamitengo yotsika ya pH.

M'mapangidwe a pharmaceuticals,Mtengo wa HPMCNthawi zambiri amagwiritsidwa ntchito ngati filimu yakale, thickener, kapena stabilizer. Makhalidwe ake osungunuka ndi ofunikira pakuwongolera mbiri yotulutsa mankhwala, kukhuthala kwa mapangidwe, komanso kukhazikika kwa emulsion kapena kuyimitsidwa.

pomwe HPMC nthawi zambiri imasungunuka pamitundu yambiri ya pH, machitidwe ake osungunuka amatha kusinthidwa bwino posintha pH ya yankho ndikusankha giredi yoyenera ya HPMC kutengera zomwe mukufuna.