Singabahlinzeki bomhlaba wonke bemishini yokukhiqiza izimonyo, ukudla kanye nemithi eminyakeni engama-20. Ikakhulukazi ekwenzeni i-mixer, kukhona okuhlangenwe nakho kokwenza okucebile, ubuchwepheshe obuthuthukisiwe kakade obunefektri etholakala esifundazweni saseJiangsu.
Ekwenziweni kwe-mixer, ingenziwa ngokwezifiso ngokusekelwe ekufuneni. Njengoba umshini uyi-vacuum yokuzikhethela, ukuxuba, ukufudumeza, i-homogenizer hamba ngomsebenzi we-emulsion, njll. Ngakho-ke umshini uzokwenziwa ngokuya ngenqubo ethile yokwenza umkhiqizo.
Sisebenzisa amakhukhi ukuthuthukisa ulwazi lwakho. Ngokuqhubeka nokuphequlula leli sayithi, uyavumelana nokusebenzisa kwethu amakhukhi. Ulwazi olwengeziwe.
Ngokomthetho wesibili we-thermodynamics, imikhiqizo eminingi yokunakekelwa kwesikhumba ayizinzile ngokwemvelo ngoba le mikhiqizo iyinhlanganisela yezinto ezimbili noma ngaphezulu ezingahlangani. Ukuqinisekisa impilo yeshalofu, le mikhiqizo kufanele yengezwe ngezinzinzisi ezifanele. Ngokuvamile, ama-surfactants e-ionic noma ama-nonionic ayengezwa njengama-emulsifiers.
Kukholelwa ukuthi ama-amphiphile anesisindo esiphansi kangaka enza izimonyo zingahambisani nesikhumba. Ngakho-ke, imboni yezimonyo ibheka ama-lotions angenawo ama-surfactant angathatha indawo yokwakheka kwendabuko. Ukuze kukhiqizwe imikhiqizo ezinzile ngokwanele futhi ejabulisa ngobuhle, ezinye izindlela ezithembisayo zihlanganisa ama-emulsifiers e-polymer noma izinhlayiya eziqinile njengeziqinisi.
Ngaphezu kokusebenzisa izindlela zokwakheka ezivamile, ama-emulsion angakwazi ukuzinza ngokusebenzisa ama-macromolecule afanelekile esikhundleni sama-surfactants aphansi esisindo samangqamuzana. Ukuzinza kwe-emulsion kuvame ukuthuthukiswa ngokungeza ama-polymers ukuze ashube futhi akhulise isivuno sesigaba esiqhubekayo.
Kodwa-ke, ukuze kuthuthukiswe ukusebenza, ama-polymer aphumayo njenge-hydroxypropyl methylcellulose noma i-carbomer 1342 angasetshenziswa njenge-emulsifier eyinhloko. Lawa ma-polymer enza amafilimu ahlangene obuso avimbela ngempumelelo ukuhlangana kwamaconsi kawoyela. Kulesi simo, umphumela wokuzinza wokwandisa i-viscosity yesigaba sangaphandle awubalulekile.
Imiqondo enjalo yokuqamba ivame ukubizwa ngokuthi ama-hydrolipid dispersions noma ama-aqueous dispersive gels, afaneleka kakhulu emikhiqizweni yokuvikela ilanga futhi ngenxa yalokho aziwa ngokuthi ukwakheka “okungenayo i-emulsifier-free”. Ngokombono womzimba kanye namakhemikhali lokhu akulungile. (Ngokuvumelana ne-International Union of Pure and Applied Chemistry, izici ze-emulsifier zichazwa kanje: I-emulsifier i-surfactant. Yehlisa ukungezwani kobuso be-solvent medium futhi ngenxa yalokho iba nomthelela omuhle ekukhangiseni ngenani elincane le-solvent. i-emulsifier ingaphromotha ukwakheka kwama-emulsion noma ikhulise ukuzinza kwawo kwe-colloidal ngokunciphisa okukodwa noma kokubili kokuhlanganisa kanye namazinga okuhlangana.)
Okuhlukanisa lezi zakhiwo kuma-emulsions azinziswe ama-emulsifiers "endabuko" yikhono lawo lokubangela ukucasuka: ama-polymer emulsifiers anesisindo esiphezulu se-molecular ngakho-ke awakwazi ukungena ku-stratum corneum. Ngakho-ke, ukusebenzisana okubi okufana ne-Majorca Acne akulindelekile. Yingakho zibizwa ngokuthi “emulsifier-free”. Ithebula 1 libonisa izibonelo ezithile zakudala.
I-acrylate/C10-30 i-alkyl acrylate crosspolymer isetshenziswe njenge-emulsifier ye-polymer ku-Formula A. I-Hydroxypropyl methylcellulose kanye ne-polyacrylic acid isetshenziswe njengeziqinisi. I-acrylic copolymer iyi-polymer emulsifier carbomer 1342 elungiswe nge-C10-30 alkyl acrylate futhi yaxhunyaniswa ne-alyl pentaerythritol.
I-lipophilic alkyl acrylate moiety ibuswa yi-hydrophilic acrylic acid moiety. I-macromolecule ewumphumela inesisindo samangqamuzana angu-4 x 109. Impahla ayincibiliki, kodwa uma ingathathi hlangothi ngesisekelo esifanelekile yanda izikhathi ezifika ku-1000.
Ama-emulsifiers e-Carbomer polymer akha ungqimba lwejeli eliwugqinsi elivikelayo elizungeze ithonsi ngalinye lamafutha esigabeni esimanzi sokugxiliswa kwe-electrolyte ephansi, ngamaketanga e-alkyl e-hydrophobic abambelele esigabeni sikawoyela. Imithamo ejwayelekile ye-polymer emulsifiers ka-0.1% kuya ku-0.3% kuphela iyadingeka ukuze kuhlanganiswe uwoyela ofika ku-20%.
Uma isigcobo sihlangana nesikhumba esine-electrolyte, siyantengantenga ngoba ungqimba lwejeli eliyisivikelo luyavuvukala ngokushesha. Ngemva kokukhipha isigaba samafutha, ifilimu elincane lamafutha lihlala esikhumbeni. Le nqubo yenza kube lula ukwenza imikhiqizo yokuvikela ilanga ukuthi, naphezu kwezakhiwo zayo ze-hydrophilic, imelana namanzi ngesikhathi sokusetshenziswa.
Ama-emulsions aqiniswe yi-acrylate/C10-30 alkyl acrylate cross-polymers angalungiswa ngezindlela eziqondile noma ezingaqondile (bheka Ithebula 2).
Ithebula 2 Uhlelo lokulungiswa kwamajeli ahlakazeke ngamanzi kusetshenziswa ama-emulsifiers e-polymer ngokungaqondile noma ngokuqondile.
Ukuze uvimbele ukuwohloka kwemishini yama-emulsifiers e-polymer esisindo samangqamuzana aphezulu, ama-homogenizer aphezulu kufanele asetshenziswe ngokuqapha njengoba lokhu kungase kunciphise ukuzinza kwe-emulsion. Ngokuvamile, ububanzi be-droplet obujwayelekile bezinto ezinjalo zingama-20-50 μm. Kodwa lokhu akunawo umthelela omubi ekuzinzeni komzimba.
Uma amasistimu ahlakazeke kahle (ama-microns angu-1-5) ekhethelwa izinjongo zobuhle, kuyanconywa ukuthi kwengezwe i-amphiphilic co-emulsifier, isibonelo i-sorbitan monooleate. Nokho, amafomula anjalo ngeke abizwe ngokuthi “ayi-emulsifier-free.”
Nakuba i-Formulation B (bona ngezansi kweThebula 1) futhi iwuhlobo lokuhlakazeka kwe-hydrolipid, isebenzisa kuphela i-hydroxypropyl methylcellulose (HPMC) njenge-polymer emulsifier.
Iziqalo ezisebenzisa i-HPMC njenge-polymer emulsifier zisebenza kancane ngokuphathelene nama-electrolyte uma kuqhathaniswa ne-water-lipid dispersions ezisebenzisa i-polymer emulsifier carbomer 1342. Ngakho, ama-emulsions kawoyela/amanzi lapho kusetshenziswa isisombululo saline saline sangaphandle futhi sihlale sizinzile ngesikhathi sokugcinwa.
Ngenxa yokucindezeleka komshini lapho isetshenziswa esikhumbeni, i-lotion ingase ibhujiswe kancane futhi yakhe ifilimu elinamafutha amancane esikhumbeni, okunciphisa ukugeleza kwesikhumba. Ngemva kokuba amanzi ehwamukile, ingxenye ye-lotion isala esikhumbeni, yakha ifilimu eguquguqukayo lapho amaconsi kawoyela elungiswa ku-matrix ye-polymer.
Ama-emulsions azinzile we-HPMC alungiswa kusetshenziswa i-rotor-stator homogenizer njenge-Ultra Turrax®. I-homogenizer ikhiqiza amaconsi amancane angu-2–5 µm ngosayizi. Ukufakwa kwamandla aphezulu kusuka ku-ultrasonic noma i-high pressure homogenization ingasetshenziswa ukukhiqiza ama-nanoemulsions nge-diameter ephakathi kwe-100-500 nm.
Ama-nanoemulsions azinziswe yi-HPMC angacutshungulwa ngokubanda kusukela esigabeni se-liquid lipid. Ukuze uthole i-pre-emulsion engahluziwe, isigaba samafutha e-liquid kanye nesisombululo se-polymer enamanzi kwahlanganiswa ekamelweni lokushisa. I-pre-emulsion idluliselwa nge-homogenizer ephezulu yokucindezela ku-20-90 MPa izikhathi eziningana ukuze uthole i-nanoemulsion yokugcina.
Nakuba ngokobuchwepheshe kungenzeka ukwandisa ingcindezi ngaphezu kobubanzi obufanele ngaphandle kwezinkinga, lokhu ngokuvamile kubangela amathonsi amasayizi amakhulu futhi akuzuzi ukuhlakazeka okuphezulu okufiswayo. Lesi simo sibizwa ngokuthi i-overprocessing futhi iyisici esivamile se-emulsions ye-polymer-stabilized.
Esinye isici esihlukile sama-emulsions aqiniswe yi-HPMC ukuthi angakwazi ukuvalwa inzalo ku-autoclave ngaphandle kokuwohloka okukhulu kwekhwalithi yawo. Lokhu kungenxa yokuthi babonisa inguquko yejeli ye-thermoreversible. Emazingeni okushisa angaphezu kuka-60 °C, isigaba sangaphandle siyajiya futhi sivimbele ukunyakaza kwamaconsi kawoyela ahlakazekile.
Amathonsi awakwazi ukungqubuzana futhi izinga lokuhlanganisa cishe alinakwa. Ngakho-ke, abaklami bangakha ama-emulsions kawoyela emanzini ngaphandle kwezilondolozi uma kusetshenziswa ukupakishwa okumelana nokungcoliswa kabusha.
Njengoba kushiwo ngaphambili, ama-emulsions nawo angaqiniswa kuphela ngomphumela wokwenza i-viscosity wokwengeza ama-polymers anjengama-carbomers (i-polyacrylic acid). Lezi zakhiwo zibizwa ngokuthi ama-emulsions "quasi" ngoba umphumela wokuzinzisa we-polymer awubandakanyi umsebenzi ohlangene. Imikhiqizo yezohwebo efanelekile, evame ukubizwa ngokuthi "ama-balms", ngokuvamile iqukethe amanani amancane e-lipids ahlakazwe ku-hydrogel.
Ukuhlakazwa kahle kwe-lipids kuqinisekisa ukuzinza ngokomzimba nempilo eyanele yeshelufu. Lesi silinganiso kanye nengcindezi yesivuno sesigaba sangaphandle kunciphisa ukugeleza kwamaconsi, ngaleyo ndlela kucindezela ngempumelelo i-emulsification kanye nokuhlangana kwamaconsi kawoyela.
Sikhulume noSolwazi u-Hongxia Wang wase-Queensland University of Technology mayelana nephrojekthi entsha ethemba ukusebenzisa i-graphene nezinye izinto zekhabhoni eshibhile ukuze kukhiqizwe amaseli elanga e-perovskite asebenziseka kalula angabizi kakhulu.
Kule ngxoxo, u-AzoNano ukhuluma noprofesa uMoti Segev no-Vladimir Shalaev, abaye bathola izinto ezimangalisayo kumakristalu esikhathi sezithombe ezibekela inselele ucwaningo olukhona kanye nemibono.
Kule ngxoxo, sixoxa ngendlela entsha ye-Raman spectroscopy ethuthukisiwe esebenzisa ama-nanopockets ukuze ibambe ama-molecule aqondiwe, okuvumela ukutholwa okubucayi kakhulu kwezinqubo zamakhemikhali.
Amakhamera e-ClearView scintillation andisa amandla e-routine transmission electron microscopy (TEM).
I-high-throughput co-localization imaging kanye ne-in situ nanoindentation kusetshenziswa i-Bruker Hysitron PI 89 Auto SEM.
Funda mayelana ne-Phe-nx's NANOS, i-SEM yebhentshiphuphu yokuhlaziya eyenza ukuhlaziya okuyisisekelo okusheshayo futhi kulula ukuyifaka nokusebenzisa.
Isikhathi sokuthumela: Nov-23-2023