1. Isakhiwo Sekhemikhali se-HPMC:
I-HPMC iyi-semi-synthetic, inert, i-viscoelastic polymer etholakala ku-cellulose. Yakhiwe ngamayunithi aphindaphindayo ama-molecule eglucose axhunywe ndawonye, anamazinga ahlukahlukene okushintsha. Ukushintsha kuhilela i-hydroxypropyl (-CH2CHOHCH3) kanye namaqembu e-methoxy (-OCH3) anamathiselwe kumayunithi we-anhydroglucose we-cellulose. Lokhu kushintsha kunikeza izakhiwo ezihlukile ku-HPMC, okuhlanganisa nokuncibilika kwayo emanzini.
2. I-Hydrogen Bonding:
Esinye sezizathu eziyinhloko zokuncibilika kwe-HPMC emanzini yikhono layo lokwakha amabhondi e-hydrogen. Ukuhlanganiswa kwe-hydrogen kwenzeka phakathi kwamaqembu e-hydroxyl (OH) e-HPMC nama-molecule amanzi. Amaqembu e-hydroxyl kuma-molecule e-HPMC angasebenzisana nama-molecule amanzi ngokusebenzisa i-hydrogen bonding, kube lula inqubo yokuhlakazeka. Lawa mandla e-intermolecular abalulekile ekwephuleni amandla akhangayo phakathi kwama-molecule e-HPMC nokwenza ukuthi ahlakazeke emanzini.
3. Iziqu Zokushintsha:
I-degree of substitution (DS) ibhekisela enanini elimaphakathi le-hydroxypropyl namaqembu e-methoxy ngeyunithi ngayinye ye-anhydroglucose ku-molecule ye-HPMC. Amanani aphezulu e-DS ngokuvamile athuthukisa ukuncibilika kwamanzi kwe-HPMC. Lokhu kungenxa yokuthi inani elikhulayo lama-hydrophilic substituents lithuthukisa ukusebenzisana kwe-polymer nama-molecule amanzi, okugqugquzela ukuhlakazeka.
4. Isisindo se-Molecular:
Isisindo samangqamuzana e-HPMC siphinde sibe nomthelela ekuncibilikeni kwayo. Ngokuvamile, amabanga aphansi esisindo samangqamuzana e-HPMC abonisa ukuncibilika okungcono emanzini. Lokhu kungenxa yokuthi amaketanga e-polymer amancane anezindawo ezifinyeleleka kalula zokusebenzelana nama-molecule amanzi, okuholela ekuhlakazweni ngokushesha.
5. Ukuziphatha Okuvuvukala:
I-HPMC inamandla okuvuvukala kakhulu lapho ichayeke emanzini. Lokhu kuvuvukala kwenzeka ngenxa yemvelo ye-polymer's hydrophilic kanye nekhono layo lokumunca ama-molecule amanzi. Njengoba amanzi engena ku-matrix ye-polymer, aphazamisa amandla e-intermolecular phakathi kwamaketanga e-HPMC, okuholela ekuhlukaneni kwawo kanye nokuhlakazeka ku-solvent.
6. I-Dispersion Mechanism:
Ukuncibilika kwe-HPMC emanzini nakho kuthonywa indlela yayo yokusabalalisa. Uma i-HPMC yengezwa emanzini, iba nenqubo yokumanzisa, lapho ama-molecule amanzi ezungeza izinhlayiya ze-polymer. Kamuva, izinhlayiya ze-polymer zihlakazeka kuyo yonke i-solvent, zisizwa ukuyaluza noma ukuxubana kwemishini. Inqubo yokusabalalisa iqhutshwa ukuhlangana kwe-hydrogen phakathi kwe-HPMC nama-molecule amanzi.
7. Amandla e-Ionic ne-pH:
Amandla e-ionic kanye ne-pH yesisombululo kungathinta ukunyibilika kwe-HPMC. I-HPMC incibilika kakhulu emanzini ngamandla e-ionic aphansi kanye ne-pH eseduze-emaphakathi. Izisombululo zamandla e-ionic aphezulu noma izimo ze-pH ezeqisayo zingaphazamisa ukubopha kwe-hydrogen phakathi kwe-HPMC nama-molecule wamanzi, ngaleyo ndlela kunciphise ukunyibilika kwayo.
8. Izinga lokushisa:
Izinga lokushisa lingaphinda libe nomthelela ekuncibilikeni kwe-HPMC emanzini. Ngokuvamile, amazinga okushisa aphezulu athuthukisa izinga lokuqedwa kwe-HPMC ngenxa yokwanda kwamandla e-kinetic, okukhuthaza ukunyakaza kwamangqamuzana nokusebenzisana phakathi kwe-polymer nama-molecule amanzi.
9. Ukugxila:
Ukugxila kwe-HPMC esixazululweni kungaba nomthelela ekuncibilikeni kwayo. Ezimweni eziphansi, i-HPMC incibilika kalula emanzini. Kodwa-ke, njengoba ukugxila kukhula, amaketanga e-polymer angase aqale ukuhlangana noma abambene, okuholela ekwehleni kokuncibilika.
10. Iqhaza Ekwenziweni Kwemithi:
I-HPMC isetshenziswa kakhulu ekwenziweni kwemithi njengepolymer eyi-hydrophilic ukuze kuthuthukiswe ukunyibilika kwezidakamizwa, i-bioavailability, kanye nokukhululwa okulawulwayo. Ukunyibilika kwayo okuhle kakhulu kwamanzi kuvumela ukulungiswa kwamafomu omthamo ozinzile futhi ahlakazeka kalula njengamaphilisi, amaphilisi, kanye nokumiswa.
ukunyibilika kwe-HPMC emanzini kubangelwa ukwakheka kwayo kwamakhemikhali okuyingqayizivele, okuhlanganisa i-hydrophilic hydroxypropyl kanye namaqembu e-methoxy, okwenza kube lula ukuhlangana kwe-hydrogen nama-molecule amanzi. Ezinye izici ezifana nezinga lokushintsha, isisindo samangqamuzana, ukuziphatha kokuvuvukala, indlela yokuhlakazeka, amandla e-ionic, i-pH, izinga lokushisa, nokugxilisa ingqondo nakho kuthonya izici zayo zokuncibilika. Ukuqonda lezi zici kubalulekile ekusebenziseni i-HPMC ngempumelelo ezinhlelweni ezehlukene, okuhlanganisa ezemithi, ukudla, izimonyo, nezinye izimboni.
Isikhathi sokuthumela: Mar-21-2024