Focus on Cellulose ethers

Qeto ea Likahare tse ling ho Non-ionic Cellulose Ether ka Gas Chromatography

Non-ionic Cellulose Ether ka Gas Chromatography

Likahare tsa li-substituents tsa ether e seng ea ionic cellulose li ne li khethoa ke chromatography ea khase, 'me liphetho li ne li bapisoa le titration ea lik'hemik'hale ho latela nako e jang nako, ts'ebetso, ho nepahala, ho pheta-pheta, litšenyehelo, joalo-joalo,' me mocheso oa kholomo o ile oa tšohloa. Tšusumetso ea maemo a chromatographic joalo ka bolelele ba kholomo ho phello ea karohano. Liphetho li bonts'a hore chromatography ea khase ke mokhoa oa tlhahlobo o lokelang ho tsebahala.
Mantsoe a bohlokoa: ether e seng ea ionic cellulose; chromatography ea khase; dikahare tsa sebaka

Nonionic cellulose ethers e kenyelletsa methylcellulose (MC), hydroxypropylmethylcellulose (HPMC), hydroxyethylcellulose (HEC), joalo-joalo. Lisebelisoa tsena li sebelisoa haholo meriana, lijo, petroleum, joalo-joalo lisebelisoa tsa ionic cellulose ether, hoa hlokahala ho tseba litaba tsa li-substituents ka nepo le ka potlako. Hajoale, bahlahisi ba bangata ba malapeng ba sebelisa mokhoa oa khale oa ho etsa tlhahlobo ea lik'hemik'hale bakeng sa tlhahlobo, e leng mosebetsi o boima le o thata ho netefatsa ho nepahala le ho pheta-pheta. Ka lebaka lena, pampiri ena e ithuta mokhoa oa ho khetholla likahare tsa li-non-ionic cellulose ether substituents ka chromatography ea khase, e hlahloba lintlha tse amang liphello tsa liteko, 'me e fumana liphello tse ntle.

1. Teko
1.1 Seletsa
GC-7800 gas chromatograph, e hlahisoang ke Beijing Purui Analytical Instrument Co., Ltd.
1.2 Li-reagents
Hydroxypropyl methylcellulose (HPMC), hydroxyethylcellulose (HEC), e entsoeng lapeng; methyl iodide, ethyl iodide, isopropane iodide, hydroiodic acid (57%), toluene, adipic acid, o-di Toluene e ne e le ea sehlopha sa tlhahlobo.
1.3 Qeto ea chromatography ea khase
1.3.1 Maemo a chromatography ea khase
Kholomo ea tšepe e sa hloekang ((SE-30, 3% Chmmosorb, WAW DMCS); mocheso oa kamore ea mouoane 200 ° C; detector: TCD, 200 ° C; mocheso oa kholomo 100 ° C; khase e tsamaisang: H2, 40 mL / min.
1.3.2 Tokisetso ea tharollo e tloaelehileng
(1) Tokisetso ea tharollo e tloaelehileng ea ka hare: Nka hoo e ka bang 6.25g ea toluene 'me u behe ka har'a 250mL volumetric flask, hlapolla letšoao ka o-xylene, sisinya hantle 'me u behelle ka thōko.
(2) Tokiso ea tharollo e tloaelehileng: lisampole tse fapaneng li na le litharollo tsa maemo a tšoanang, 'me lisampole tsa HPMC li nkuoa e le mohlala mona. Ka vial e loketseng, eketsa tekanyo e itseng ea adipic acid, 2 mL ea hydroiodic acid le tharollo e tloaelehileng ea ka hare, 'me u lekanye vial ka nepo. Eketsa palo e loketseng ea iodoisopropane, e lekanye, 'me u bale palo ea iodoisopropane e kentsoeng. Kenya methyl iodide hape, lekanya ka ho lekana, bala palo e eketsang methyl iodide. A thothomele ka botlalo, e tlohelle e eme bakeng sa stratification, 'me e e behe hole le leseli hore e tle e sebelisoe hamorao.
1.3.3 Tokiso ea tharollo ea mohlala
Beha ka nepo 0.065 g ea sampole e omeletseng ea HPMC ka har'a mochini o nang le mabota a 5 mL, eketsa boima bo lekanang ba asiti ea adipic, 2 mL ea tharollo e tloaelehileng ea kahare le hydroiodic acid, koala botlolo ea karabelo kapele, 'me u e lekanye ka nepo. Hlakola, 'me u chese ka 150 ° C metsotso e 60, ho sisinyeha hantle nakong ea nako. Pholile le bekha. Haeba tahlehelo ea boima ba 'mele pele le ka mor'a karabelo e kholo ho feta 10 mg, tharollo ea mohlala ha e sebetse' me tharollo e lokela ho lokisoa hape. Kamora hore tharollo ea sampole e lumelloe ho ema bakeng sa stratification, taka ka hloko 2 μL ea tharollo ea karolo e kaholimo ea organic, e ente ka har'a chromatograph ea khase, 'me u tlalehe spectrum. Lisampole tse ling tse seng tsa ionic cellulose ether li ile tsa tšoaroa ka mokhoa o ts'oanang le HPMC.
1.3.4 Molao-motheo oa ho lekanya
Ha re nka mohlala oa HPMC, ke cellulose alkyl hydroxyalkyl ether e tsoakiloeng, e futhumatsoang le asiti ea hydroiodic ho roba litlamo tsohle tsa methoxyl le hydroxypropoxyl ether le ho hlahisa iodoalkane e tsamaellanang .
Ka tlas'a maemo a phahameng a mocheso le moea, ka adipic acid e le catalyst, HPMC e sebetsana le hydroiodic acid, 'me methoxyl le hydroxypropoxyl li fetoloa methyl iodide le isopropane iodide. Ho sebelisa o-xylene e le monyebetsi le mokelikeli, karolo ea ho thusa le ho monya ke ho khothalletsa karabelo e feletseng ea hydrolysis. Toluene e khethoa e le tharollo e tloaelehileng ea ka hare, 'me methyl iodide le isopropane iodide li sebelisoa e le tharollo e tloaelehileng. Ho ea ka libaka tse phahameng tsa maemo a ka hare le tharollo e tloaelehileng, litaba tsa methoxyl le hydroxypropoxyl ka sampuli li ka baloa.

2. Liphetho le lipuisano
Kholomo ea chromatographic e sebelisitsoeng tekong ena ha se polar. Ho ea ka ntlha e belang ea karolo ka 'ngoe, tlhōrō ea taelo ke methyl iodide, isopropane iodide, toluene le o-xylene.
2.1 Papiso lipakeng tsa chromatography ea khase le titration ea lik'hemik'hale
Boikemisetso ba methoxyl le hydroxypropoxyl content ea HPMC ka titration ea lik'hemik'hale e batla e hōlile, 'me hona joale ho na le mekhoa e' meli e sebelisoang hangata: mokhoa oa Pharmacopoeia le mokhoa o ntlafetseng. Leha ho le joalo, mekhoa ena e 'meli ea lik'hemik'hale e hloka ho lokisoa ha litharollo tse ngata, ts'ebetso e rarahane, e ja nako,' me e ameha haholo ke lintlha tse ka ntle. Ha re bua, chromatography ea khase e bonolo haholo, e bonolo ho ithuta le ho e utloisisa.
Liphetho tsa litaba tsa methoxyl (w1) le hydroxypropoxyl content (w2) ho HPMC li khethiloe ke chromatography ea khase le titration ea lik'hemik'hale ka ho latellana. Ho ka bonoa hore liphello tsa mekhoa ena e 'meli e haufi haholo, e bontšang hore mekhoa ka bobeli e ka tiisa ho nepahala ha liphello.
Ho bapisa lik'hemik'hale tsa lik'hemik'hale le chromatography ea khase mabapi le tšebeliso ea nako, boiketlo ba ts'ebetso, ho pheta-pheta le litšenyehelo, liphetho li bontša hore molemo o moholo ka ho fetisisa oa chromatography ea mohato ke ho ba bonolo, ho potlaka le ho sebetsa hantle haholo. Ha ho hlokahale ho lokisetsa palo e kholo ea li-reagents le tharollo, 'me ho nka metsotso e fetang leshome feela ho lekanya sampuli,' me nako ea sebele e bolokiloeng e tla ba kholo ho feta lipalo-palo. Mokhoeng oa titration oa lik'hemik'hale, phoso ea motho ha a ahlola sebaka sa ho qetela sa titration e kholo, athe liphetho tsa tlhahlobo ea khase ea chromatography ha li amehe hakaalo ke lintlha tsa batho. Ho feta moo, chromatography ea khase ke mokhoa oa karohano o arolang lihlahisoa tsa karabelo le ho li lekanya. Haeba e ka sebelisana le lisebelisoa tse ling tsa ho lekanya, tse kang GC/MS, GC/FTIR, joalo-joalo, e ka sebelisoa ho tsebahatsa disampole tse ling tse rarahaneng tse sa tsejoeng (modified fibers) Plain ether products) li molemo haholo, tse ke keng tsa bapisoa le lik'hemik'hale. . Ho feta moo, ho ikatisa ha sephetho sa chromatography ea khase ho molemo ho feta ea titration ea lik'hemik'hale.
Bobebe ba chromatography ea khase ke hore litšenyehelo li holimo. Litšenyehelo ho tloha ho thehoeng ha seteishene sa chromatography ea khase ho ea tlhokomelong ea sesebelisoa le khetho ea kholomo ea chromatographic e phahame ho feta ea mokhoa oa ho fetola lik'hemik'hale. Litlhophiso tse fapaneng tsa lisebelisoa le maemo a liteko le tsona li tla ama liphetho, joalo ka mofuta oa Detector, kholomo ea chromatographic le khetho ea karolo e emeng, jj.
2.2 Tšusumetso ea maemo a chromatography ea khase ho liphetho tsa qeto
Bakeng sa liteko tsa chromatography ea khase, senotlolo ke ho fumana maemo a nepahetseng a chromatographic ho fumana liphetho tse nepahetseng haholoanyane. Tekong ena, hydroxyethylcellulose (HEC) le hydroxypropylmethylcellulose (HPMC) li ile tsa sebelisoa e le lisebelisoa tse tala, 'me ho ile ha ithutoa tšusumetso ea lintlha tse peli, mocheso oa kholomo le bolelele ba kholomo.
Ha tekanyo ea karohano R ≥ 1.5, e bitsoa karohano e feletseng. Ho ea ka litokisetso tsa "Chinese Pharmacopoeia", R e lokela ho ba kholo ho feta 1.5. Ha e kopantsoe le mocheso oa kholomo lithempereichara tse tharo, tharollo ea karolo ka 'ngoe e kholo ho feta 1.5, e finyellang litlhoko tsa motheo tsa karohano, e leng R90°C>R100°C>R110°C. Ha ho nahanoa ka ntlha ea mohatla, ntlha ea mohatla r> 1 ke tlhōrō ea mohatla, r<1 ke tlhōrō e ka pele, 'me e haufi-ufi ke 1, ho ntlafatsa ts'ebetso ea kholomo ea chromatographic. Bakeng sa toluene le ethyl iodide, R90°C>R100°C>R110°C; o-xylene ke mokelikeli o nang le ntlha e phahameng ka ho fetisisa e belang, R90°C
Tšusumetso ea bolelele ba kholomo liphethong tsa liteko e bonts'a hore tlas'a maemo a ts'oanang, bolelele ba kholomo ea chromatographic bo fetotsoe. Ha ho bapisoa le kholomo e pakiloeng ea 3m le 2m, liphetho tsa tlhahlobo le qeto ea kholomo ea 3m li betere, 'me ha kholomo e le telele, ho na le ts'ebetso e ntle ea kholomo. Ha boleng bo phahame, sephetho se ka tšeptjoa haholoanyane.

3. Qetello
Hydroiodic acid e sebelisoa ho senya bond ether ea non-ionic cellulose ether ho hlahisa iodide e nyenyane ea molek'hule, e arohanngoa ke chromatography ea khase 'me e lekanyelitsoe ka mokhoa o tloaelehileng oa ka hare ho fumana litaba tsa sebaka. Ntle le hydroxypropyl methylcellulose, cellulose ethers tse loketseng mokhoa ona li kenyelletsa hydroxyethyl cellulose, hydroxyethyl methyl cellulose, le methyl cellulose, mme mokhoa oa kalafo oa sampole o tšoana.
Ha ho bapisoa le mokhoa o tloaelehileng oa ho fetola lik'hemik'hale, tlhahlobo ea khase ea chromatography ea likarolo tse ling tsa non-ionic cellulose ether e na le melemo e mengata. Molao-motheo o bonolo ebile o bonolo ho o utloisisa, ts'ebetso e bonolo, 'me ha ho hlokahale ho lokisetsa meriana le li-reagents tse ngata, tse bolokang nako ea ho hlahloba haholo. Liphello tse fumanoang ka mokhoa ona li lumellana le tse fumanoang ka lik'hemik'hale tsa lik'hemik'hale.
Ha o sekaseka litaba tse ling ka chromatography ea khase, ho bohlokoa haholo ho khetha maemo a nepahetseng le a nepahetseng a chromatographic. Ka kakaretso, ho fokotsa mocheso oa kholomo kapa ho eketsa bolelele ba kholomo ho ka ntlafatsa tharollo ka nepo, empa ho lokela ho nkuoa tlhokomelo ho thibela likarolo hore li se ke tsa fokotseha ka lebaka la mocheso o tlase haholo.
Hona joale, bahlahisi ba bangata ba malapeng ba ntse ba sebelisa lik'hemik'hale tsa lik'hemik'hale ho fumana hore na ke lintho life tse ling. Leha ho le joalo, ha ho nahanoa ka melemo le likotsi tsa likarolo tse fapaneng, chromatography ea khase ke mokhoa o bonolo le o potlakileng oa tlhahlobo o lokelang ho khothaletsoa ho latela mekhoa ea nts'etsopele.


Nako ea poso: Feb-15-2023
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