Ukusabela kwamakhemikhali ekuvubeleni kwe-hydroxypropyl methylcellulose

I-Hydroxypropyl methylcellulose (HPMC)iyinhlanganisela ye-polymer encibilika emanzini evame ukusetshenziswa emkhakheni wezimboni nezokwelapha, futhi inenani elibanzi lamanani okusebenza, njengokukhululwa okulawulwa yizidakamizwa, ukucubungula ukudla nezinto zokwakha. Ukusabela kwamakhemikhali enqubweni yayo yokuvutshelwa kuhlobene kakhulu nokuwohloka nokuguqulwa kwe-cellulose kanye nemisebenzi ye-metabolic yama-microorganisms. Ukuze siqonde kangcono ukusabela kwamakhemikhali e-HPMC enqubweni yokuvutshelwa, sidinga kuqala ukuqonda isakhiwo sayo esiyisisekelo kanye nenqubo yokuwohloka kwe-cellulose.

1. Isakhiwo esiyisisekelo kanye nezakhiwo ze-hydroxypropyl methylcellulose

I-HPMC iwukuphuma kokunye okutholwe ngokuguqulwa kwamakhemikhali kwe-cellulose yemvelo (Cellulose). Umgogodla weketango layo lamangqamuzana ama-molecule e-glucose (C6H12O6) axhunywe ngamabhondi e-β-1,4 glycosidic. I-Cellulose ngokwayo inzima ukuhlakazeka emanzini, kodwa ngokwethula amaqembu e-methyl (-OCH3) kanye ne-hydroxypropyl (-C3H7OH), ukuncibilika kwamanzi kwawo kungathuthukiswa kakhulu ukuze kwakhiwe i-polymer encibilikayo. Inqubo yokuguqula ye-HPMC ngokuvamile ihlanganisa ukusabela kwe-cellulose nge-methyl chloride (CH3Cl) kanye ne-propylene alcohol (C3H6O) ngaphansi kwezimo ze-alkaline, futhi umkhiqizo owumphumela uba ne-hydrophilicity eqinile nokuncibilika.

2. Ukusabela kwamakhemikhali ngesikhathi sokuvutshelwa

Inqubo yokuvubela ye-HPMC ngokuvamile incike esenzweni samagciwane, asebenzisa i-HPMC njengomthombo wekhabhoni kanye nomthombo wezakhi. Inqubo yokuvutshelwa kwe-HPMC ihlanganisa izigaba ezilandelayo:

2.1. Ukucekelwa phansi kwe-HPMC

I-Cellulose ngokwayo yakhiwe amayunithi e-glucose axhunyiwe, futhi i-HPMC izokwehliswa amagciwane ngesikhathi sokuvutshelwa, iqale ibole ibe ushukela omncane osebenzisekayo (njenge-glucose, i-xylose, njll.). Le nqubo ngokuvamile ihilela isenzo sama-enzyme amaningi alulaza i-cellulose. Ukusabela okuyinhloko kokunciphisa kuhlanganisa:

Ukusabela kwe-Cellulose hydrolysis: Amabhondi e-β-1,4 glycosidic kuma-molecule e-cellulose azophulwa ama-cellulose hydrolases (afana ne-cellulase, i-endocellulase), akhiqize amaketanga kashukela amafushane (njengama-oligosaccharides, ama-disaccharides, njll.). Lo shukela uzophinde usetshenziswe futhi usetshenziswe ama-microorganisms.

I-Hydrolysis and degradation of HPMC: I-methyl ne-hydroxypropyl substituent ku-molecule ye-HPMC izosuswa kancane nge-hydrolysis. Indlela ethile yokusabela kwe-hydrolysis ayikaqondwa ngokugcwele, kodwa kungacatshangwa ukuthi endaweni yokuvutshelwa, ukusabela kwe-hydrolysis kwenziwa ama-enzyme akhiqizwa ama-microorganisms (njenge-hydroxyl esterase). Le nqubo iholela ekuqhekekeni kwamaketanga e-molecular HPMC kanye nokususwa kwamaqembu asebenzayo, ekugcineni kwakheke ama-molecule amancane kashukela.

2.2. Ukusabela kwe-Microbial metabolic

Uma i-HPMC seyehlisiwe yaba ama-molecule kashukela amancane, ama-microorganisms ayakwazi ukuguqula loshukela ube amandla ngokusabela kwe-enzymatic. Ngokukhethekile, ama-microorganisms abola i-glucose ibe yi-ethanol, i-lactic acid noma amanye ama-metabolites ngokusebenzisa izindlela zokuvutshelwa. Ama-microorganisms ahlukene angase asebenzise imikhiqizo ewohlokayo ye-HPMC ngezindlela ezahlukene. Izindlela ezijwayelekile ze-metabolic zihlanganisa:

Indlela ye-Glycolysis: I-glucose ichithwa ibe yi-pyruvate ngama-enzyme bese iguqulwa ibe amandla (ATP) nama-metabolites (njenge-lactic acid, i-ethanol, njll.).

Ukukhiqizwa komkhiqizo wokuvutshelwa: Ngaphansi kwezimo ze-anaerobic noma i-hypoxic, ama-microorganisms aguqula i-glucose noma imikhiqizo yayo yokuwohloka ibe ama-asidi aphilayo njenge-ethanol, i-lactic acid, i-acetic acid, njll. ngokusebenzisa izindlela zokuvutshelwa, ezisetshenziswa kakhulu ezinqubweni ezihlukene zezimboni.

2.3. Ukusabela kwe-Redox

Phakathi nenqubo yokuvutshelwa kwe-HPMC, amanye amagciwane angase aqhubeke nokuguqula imikhiqizo ephakathi ngokusabela kwe-redox. Isibonelo, inqubo yokukhiqiza i-ethanol ihambisana nokusabela kwe-redox, i-glucose i-oxidized ukuze ikhiqize i-pyruvate, bese i-pyruvate iguqulwa ibe i-ethanol ngokusabela kokunciphisa. Lokhu kusabela kubalulekile ekugcineni ibhalansi ye-metabolic yamaseli.

3. Lawula izici enqubweni yokuvutshelwa

Phakathi nenqubo yokuvutshelwa kwe-HPMC, izici zemvelo zinethonya elibalulekile ekuphenduleni kwamakhemikhali. Isibonelo, i-pH, izinga lokushisa, okuqukethwe komoyampilo okuncibilikisiwe, ukugxiliswa komthombo wezakhi, njll. kuzothinta izinga lokwenziwa kwezinqubo ze-microorganisms kanye nohlobo lwemikhiqizo. Ikakhulukazi izinga lokushisa kanye ne-pH, umsebenzi wama-enzyme e-microbial ungahluka kakhulu ngaphansi kwezimo ezihlukene zokushisa nezimo ze-pH, ngakho-ke kuyadingeka ukulawula ngokunembile izimo zokuvutshelwa ukuze kuqinisekiswe ukuwohloka kwe-HPMC kanye nokuqhubeka kahle kwenqubo ye-metabolic yamagciwane.

Inqubo yokuvutshelwa kweI-HPMCkuhlanganisa ukusabela kwamakhemikhali okuyinkimbinkimbi, okuhlanganisa i-hydrolysis ye-cellulose, ukuwohloka kwe-HPMC, i-metabolism kashukela, nokukhiqizwa kwemikhiqizo yokuvutshelwa. Ukuqonda lokhu kusabela akusizi nje kuphela ukuthuthukisa inqubo yokuvutshelwa kwe-HPMC, kodwa futhi kunikeza ukusekelwa kwethiyori kokukhiqizwa kwezimboni okuhlobene. Ngokujula kocwaningo, izindlela zokuvubela ezisebenza kahle kakhulu nezongayo zingathuthukiswa esikhathini esizayo ukuze kuthuthukiswe ukusebenza kahle kokucekelwa phansi kwe-HPMC kanye nesivuno semikhiqizo, futhi kugqugquzelwe ukusetshenziswa kwe-HPMC ku-biotransformation, ukuvikelwa kwemvelo neminye imikhakha.