8 results on '"Dry Eye Disease"'
Search Results
2. Optical coherence tomography of tear meniscus in dry eye
- Author
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Celovec, Ivan, Petriček, Igor, Vukojević, Nenad, and Kalauz, Miro
- Subjects
optical coherence tomography ,tear film diagnosis ,dry eye disease ,Ocular Surface Disease Inde - Abstract
Disfunkcija suznog filma ili bolest suhog oka (DED) je multifaktorijalna i česta bolest koja rezultira simptomima nelagode i vidnim smetnjama s mogućim oštećenjem površine oka. Trenutno ne postoji test za dijagnozu i praćenje tijeka bolesti koji graduira i detektira intenzitet stanja prihvatljivom senzibilnošću i specifičnošću. Testovi su u većini slučajeva neprecizni te imaju nisku ponovljivost. Sadašnje metode dijagnosticiranja uključuju pregled na procjepnoj svjetiljci, određivanje vremena pucanja suznog filma, procjena funkcije Meibomovih žlijezda, procjena suznog meniska kao i najčešće Schirmerov test. Bez dijagnostičkog standarda kojim bi se nadzirala bolest, liječenje bolesti suhog oka najčešće je simptomatsko, tj. bazira se na dobro uzetoj anamnezi. Zbog svega navedenog, bolest suhog oka postaje rastući javnozdravstveni problem jer može značajno utjecati na vid osobe te dovesti do smanjenja kvalitete života. Tema ovog diplomskog rada je bilo istraživanje u kojem smo koristili optičku koherentnu tomografiju suznog meniska kao metodu detekcije bolesti suhog oka. U istraživanje je bilo uključeno 18 ispitanika, koji su ispunili OSDI anketni upitnik, pristupili oftalmološkom pregledu te snimanju suznog meniska optičkom koherentnom tomografijom. U istraživanju je dokazana statistička povezanost ispitivanih varijabli- površine suznog meniska (p= 0,036), testa nativnog pucanja suznog filma (p= 0,030) i testa pucanja suznog filma nakon ekspresije Meibomovih žlijezda (p= 0,028)., Tear film dysfunction or dry eye disease (DED) is a multifactorial and frequent disease that results in symptoms of discomfort and visual disturbances resulting in possible damage to the surface of the eye. Currently not fully standardized test for diagnosis and monitoring of disease flow. The tests are in most cases inaccurate and have low repeatability. Current methods of diagnosing include examination on slit lamp, determination of the tear breakup time, evaluation of the function of the Meibomian glands, estimation of the tear meniscus as well as the most common Schirmer test. Without a diagnostic standard to monitor the disease, treatment of dry eye diseases is usually symptomatic, i.e. essentially on a well-taken medical history. Because of all of the above, the disease of the dry eye becomes a growing public health problem because it can significantly affect the vision of a person and lead to a decrease in quality of life. Through this graduate thesis we conducted a study in which we used optical coherence tomography of tear meniscus as a method of detection of dry eye disease. The survey included 18 respondents, who fulfilled the OSDI questionnaire, accessed ophthalmological examination and tear meniscus measurements with optical coherence tomography. The study demonstrated the statistical correlation of the examined variables- tear meniscus surface area (P = 0.036), the native tear break- up time (p = 0.030) and the tear break- up time after the expression of the Meibomian glands (p = 0.028).
- Published
- 2023
3. Preformulation studies in development of nanoemulsions loaded with ibuprofen
- Author
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Grošić, Petra and Lovrić, Jasmina
- Subjects
sojino ulje ,Nanoemulzija ,Mikrofluidizacija ,Bolest suhog oka ,Ibuprofen ,Ricinusovo ulje ,soybean oil ,nanoemulsion ,glicerol ,glycerol ,Tween® 80 ,dry eye disease ,ricinusovo ulje ,sesame oil ,BIOMEDICINE AND HEALTHCARE. Pharmacy. Pharmacy ,Miglyol® 812 ,bolest suhog oka ,castor oil ,nanoemulzija ,mikrofluidizacija ,BIOMEDICINA I ZDRAVSTVO. Farmacija. Farmacija ,ibuprofen ,sezamovo ulje ,microfluidization - Abstract
Bolest suhog oka karakterizirana je hiperosmolarnošću suznog filma i subakutnom upalom. Trenutno su glavne terapijske mogućnosti nadomještanje suznog filma, stimulacija stvaranja suza i topikalni protuupalni lijekovi. Protuupalna nesteroidna djelatna tvar ibuprofen ima potencijal za liječenje blagog do umjereno teškog oblika bolesti suhog oka. U/V nanoemulzije predstavljaju farmaceutski oblik pogodan za uklapanje ibuprofena, a zbog nadoknade i stabilizacije suznog filma koje osiguravaju pomoćne tvari nanoemulzija moguć je razvoj vrlo učinkovitog lijeka. Cilj ovog diplomskog rada bio je provesti ispitivanje topljivosti ibuprofena u uljima koja su odobrena ili velikog potencijala za oftalmičku primjenu te razviti preliminarne nanoemulzije U/V tipa s uklopljenim ibuprofenom. Topljivost ibuprofena ispitana je u četiri ulja: ricinusovo ulje, sezamovo ulje, sojino ulje te Miglyol® 812, od kojih ricinusovo ulje karakterizira najveća topljivost ibuprofena. U sljedećoj fazi izrade diplomskog rada ispitana je mogućnost izrade nanoemulzija s uklopljenim ibuprofenom. Uljnu fazu su činili ibuprofen i ricinusovo ulje, a vodenu fazu neionska površinski aktivna tvar Tween® 80, sredstvo za izotonizaciju glicerol te pročišćena voda. Nanoemulzije su pripravljene visokoenergetskom metodom mikrofluidizacije, nakon čega su im određena fizičko-kemijska svojstva uključujući veličinu kapljica i raspodjelu veličina te zeta-potencijal. Pripravljene preliminarne nanoemulzije karakterizira odgovarajuća uklopljenost ibuprofena, veličina kapljica i raspodjela veličina te zeta-potencijal, stoga predstavljaju dobar temelj za daljnji razvoj oftalmičke nanoemulzije s uklopljenim ibuprofenom za liječenje bolesti suhog oka. Dry eye disease is characterized by hyperosmolarity of the tear film and subacute inflammation. Currently, the main therapeutic options are tear replacement, stimulation of tear production and topical anti-inflammatory drugs. The anti-inflammatory non-steroidal active ingredient ibuprofen has the potential to treat mild to moderate dry eye disease. U/V nanoemulsions represent a dosage form suitable for loading ibuprofen and due to compensation and stabilization of the tear film provided by excipients of the nanoemulsions, development of a very effective drug is possible. The aim of this thesis was to test the solubility of ibuprofen in oils that are approved or have high potential for ophthalmic use and to develop preliminary o/w nanoemulsions loaded with ibuprofen. The solubility of ibuprofen was tested in four oils: castor oil, sesame oil, soybean oil and Miglyol® 812. Castor oil is characterized by the highest solubility of ibuprofen. In the next phase of this thesis, the possibility of preparing nanoemulsions loaded with ibuprofen was examined. The oil phase consisted of ibuprofen and castor oil, and the water phase consisted of the nonionic surfactant Tween® 80, an isotonizing agent glycerol and purified water. Nanoemulsions were prepared using a high energy microfluidization method, after which their physicochemical properties were determined, including droplet size, size distribution and zeta potential. The prepared preliminary nanoemulsions are characterized by appropriate incorporation of ibuprofen, droplet size, size distribution and zeta-potential, therefore they represent a good basis for further development of an ophthalmic nanoemulsion loaded with ibuprofen for the treatment of dry eye disease.
- Published
- 2022
4. Stability testing of ophthalmic nanoemulsions under conditions of simulated tear turnover
- Author
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Cepetić, Dorja and Lovrić, Jasmina
- Subjects
umjetna suzna tekućina ,tyloxapol ,bolest suhog oka ,nanoemulsion ,Nanoemulzija ,Bolest suhog oka ,Tiloksapol ,Mikrofluidizacija ,Umjetna suzna tekućina ,tiloksapol ,nanoemulzija ,mikrofluidizacija ,artificial tear solution ,BIOMEDICINA I ZDRAVSTVO. Farmacija. Farmacija ,dry eye disease ,microfluidization ,BIOMEDICINE AND HEALTHCARE. Pharmacy. Pharmacy - Abstract
Bolest suhog oka jedan je od najčešćih razloga posjeta oftalmologu i pogađa milijune ljudi. Karakteriziraju ju kronična upala, hiperosmolalnost suznog filma i smanjena debljina lipidnog sloja suznog filma, što uzrokuje simptome poput pečenja, svrbeža, crvenila i suzenja oka. Prva linija liječenja bolesti suhog oka primjena je bezreceptnih kapi za oko. Zadnjih nekoliko desetljeća istražuju se kapi za oko u obliku nanoemulzija te je odobreno nekoliko lijekova u tom obliku za liječenje bolesti suhog oka. Nanoemulzije tipa U/V daju mogućnost uklapanja slabo topljivih djelatnih tvari te dulje zadržavanje na mjestu primjene, a nude i simptomatsko liječenje bez djelatne tvari, zahvaljujući sinergizmu korištenih pomoćnih tvari u vidu stabilizacije i nadoknade suznog filma. Složeni su farmaceutski oblici s nekoliko fizičko-kemijskih parametara (primjerice, veličina, raspodjela veličina i zeta-potencijal kapljica unutranje faze) koji utječu na njihovu in vivo učinkovitost. Postoji veliki interes za razvoj inovativnih i generičkih lijekova temeljenih na tehnologiji nanoemulzija, ali zbog složenosti nanoemulzija taj je razvoj vrlo izazovan. Trenutno ne postoje biorelevantne in vitro metode konstruirane na temelju ključnih fizioloških i anatomskih aspekata površine oka, a koje bi omogućile učinkovit razvoj oftalmičkih nanoemulzija. Cilj ovog diplomskog rada je ispitati stabilnost oftalmičke nanoemulzije u uvjetima simulirane izmjene suza. U tu svrhu pripravljene su jednostavne U/V nanoemulzije stabilizirane neionskom PAT te je određen utjecaj razrjeđenja vodom ili vanjskom fazom nanoemulzije na veličinu i raspodjelu veličina te zeta-potencijal kapljica nanoemulzije. Potom je određena stabilnost jednostavne nanoemulzije u uvjetima simulirane izmjene suza korištenjem umjetne suzne tekućine koja sadržava soli, ureu i glukozu. Tijekom 40 minuta ispitivanja u uvjetima kontinuiranog biorelevantnog razrjeđenja nanoemulzije stabilizirane neionskom površinski aktivnom tvari nije uočena značajnija promjena veličine i raspodjele veličina te zeta-potencijala kapljica unutarnje faze. Dry eye disease (DED) is one of the most common reasons for visiting an ophthalmologist and affects millions of people. It is characterized by chronic inflammation, hyperosmolarity of the tear film and reduced thickness of the lipid layer of the tear film, which causes symptoms such as burning, itching, redness and watering of the eye. The first line of treatment for DED is the use of over-the-counter (OTC) eye drops. For the last few decades, eye drops in the form of nanoemulsions have been researched, and several medicines in this form have been approved for treatment of DED. Oil-in-water (O/W) nanoemulsions provide the possibility of incorporating lipophilic drugs and prolonging their retention time at the site of application. Furthermore, they offer symptomatic treatment without the active substance, thanks to the synergism of the excipients, by stabilizing and replacing of the tear film. They are complex pharmaceutical forms with several physicochemical parameters (such as size, polydispersity index and zeta-potential of the internal phase droplets) which affect their in vivo efficiency. There is great interest in the development of innovative and generic drugs based on nanoemulsion technology, but due to the complexity of nanoemulsions, this development is very challenging. Currently, there are no biorelevant in vitro methods constructed on the basis of key physiological and anatomical aspects of the eye surface, which would enable the effective development of ophthalmic nanoemulsions. The aim of this thesis is to examine the stability of ophthalmic nanoemulsion under the conditions of simulated tear turnover. For this purpose, simple O/W nanoemulsions stabilized by non-ionic surfactant were prepared and the influence of dilution with water or the external phase of the nanoemulsion on the size and polydispersity index and zeta-potential of the nanoemulsion droplets was determined. Then, the stability of a simple nanoemulsion was determined under the conditions of simulated tear turnover using an artificial tear solution containing salts, urea and glucose. During 40 minutes of testing under conditions of continuous biorelevant dilution of the nanoemulsion stabilized with a nonionic surfactant, no significant change in the size, polydispersity index and zeta-potential of the internal phase droplets was observed.
- Published
- 2022
5. Razvoj oftalmičkih nanoemulzija s kationskim lipidom cetiltrimetilamonijevim bromidom
- Author
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Parac, Petra and Lovrić, Jasmina
- Subjects
lecitin ,kationski lipid ,cationic lipid ,propylene glycol monocaprylate ,makrogolglicerol ricinoleat 35 ,dry eye disease ,BIOMEDICINE AND HEALTHCARE. Pharmacy. Pharmacy ,kationska nanoemulzija ,macrogolglycerol ricinoleate 35 ,cetiltrimetilamonijev bromid (CTAB) ,lecithin ,cationic nanoemulsion ,Kationska nanoemulzija ,Bolest suhog oka ,Kationski lipid ,Cetiltrimetilamonijev bromid (CTAB) ,Propilenglikol monokaprilat ,Makrogolglicerol ricinoleat 35 ,Lecitin ,bolest suhog oka ,cetyltrimethylammonium bromide (CTAB) ,propilenglikol monokaprilat ,BIOMEDICINA I ZDRAVSTVO. Farmacija. Farmacija - Abstract
Bolest suhog oka najčešći je oblik kronične bolesti površine oka. Današnje su terapijske opcije ograničene, a lokalni kortikosteroidi, poput loteprednol etabonata, imaju potencijal za učinkovito liječenje blage do umjerene bolesti suhog oka. U posljednje vrijeme ističu se različiti terapijski nanosustavi za sigurnu i poboljšanu terapiju bolesti oka. U/V nanoemulzije niske su toksičnosti i iritacije te velikog kapaciteta za uklapanje lijekova slabo topljivih u vodi. Također, kationske nanoemulzije imaju sposobnost produljenja zadržavanja formulacije na površini oka temeljem interakcije s negativno nabijenim mucinima, a time posljedično i povećanja bioraspoloživosti lijeka. U ovom je diplomskom radu proveden razvoj formulacije oftalmičke kationske nanoemulzije kao inovativni farmaceutski oblik s potencijalom primjene u liječenju bolesti suhog oka. Cilj diplomskog rada bio je razvoj formulacije kationskih U/V nanoemulzija prikladnih za uklapanje loteprednol etabonata. Nanoemulzije su pripravljene visokoenergetskom metodom mikrofluidizacije, a njihova karakterizacija je obuhvaćala određivanje veličine kapljica unutarnje faze, indeksa polidisperznosti i zeta-potencijala. Razvoj je proveden u četiri faze: probir vrste i udjela neionske površinski aktivne tvari, probir vrste lecitina, probir udjela lecitina te ispitivanje utjecaja dodatka kationskog lipida u formulaciji. Uspješno su pripravljene kationske nanoemulzije uljne faze Capryol™ 90 stabilizirane neionskom površinski aktivnom tvari Kolliphorom® EL, lecitinom Lipoidom® S75 te kationskim lipidom cetiltrimetilamonijevim bromidom (CTAB) kao nositeljem pozitivnog naboja. Rezultati pokazuju da visoke pozitivne vrijednosti zeta-potencijala pripravljenih nanoemulzija upućuju na odgovarajuću elektrostatsku stabilizaciju kationskim lipidom CTAB-om; Kolliphor® EL u formulaciji dodatno osigurava steričku stabilizaciju; Lipoid® S75 sadrži smjesu fosfolipida koji su sastavni dio prirodnog suznog filma i pridonose njegovoj stabilnosti. Dry eye disease is the most common form of chronic ocular surface disease. Current therapy is limited, and topical corticosteroids such as loteprednol etabonate have the potential to effectively treat mild to moderate dry eye disease. Recently, various new therapeutic nanosystems have been highlighted for safe and improved treatment of eye diseases. O/W nanoemulsions are nontoxic and nonirritant and have a high capacity to incorporate poorly water-soluble drugs. Moreover, cationic nanoemulsions have the ability to prolong the retention on the surface of the eye due to interaction with negatively charged mucins, and consequently increase the bioavailability of the drug. In this thesis, the development of the formulation of ophthalmic cationic nanoemulsion as an innovative pharmaceutical form with the potential in the treatment of dry eye disease was carried out. The aim of the thesis was the development of the formulation of cationic O/W nanoemulsions suitable for incorporating loteprednol etabonate. Nanoemulsions were prepared by microfluidization, and their characterization included the determination of the internal phase droplet size, polydispersity index and zeta-potential. The development was carried out in four phases: screening of the type and content of non-ionic surfactant, screening of the type of lecithin, screening of the lecithin content and screening of the cationic lipid content. Cationic nanoemulsions of oil phase Capryol™ 90 stabilized with nonionic surfactant Kolliphor® EL, lecithin Lipoid® S75 and cationic lipid cetyltrimethylammonium bromide (CTAB) as a positive charge carrier were successfully prepared. The results show that high positive zeta-potential values of the prepared nanoemulsions indicate adequate electrostatic stabilization by the cationic lipid CTAB; Kolliphor® EL in the formulation additionally provides steric stabilization; Lipoid® S75 contains a mixture of phospholipids that are an integral part of the natural tear film and contribute to its stability.
- Published
- 2022
6. Razvoj oftalmičkih sekundarnih kationskih nanoemulzija s oligomerom kitozana
- Author
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Jaušić, Matej and Lovrić, Jasmina
- Subjects
lecitin ,microfluidisation ,lecythin ,Bolest suhog oka ,Kationska nanoemulzija ,Kitozan ,Lecitin ,Makrogolglicerol ricinoleat 35 ,Mikrofluidizacija ,makrogolglicerol ricinoleat 35 ,dry eye disease ,BIOMEDICINE AND HEALTHCARE. Pharmacy. Pharmacy ,suho oko ,kationska nanoemulzija ,macrogolglycerol ricinoleate 35 ,dry eye ,kitozan ,cationic nanoemulsion ,bolest suhog oka ,mikrofluidizacija ,chitosan ,BIOMEDICINA I ZDRAVSTVO. Farmacija. Farmacija - Abstract
Bolest suhog oka bolest je površine oka koja je u današnje vrijeme česta pojava. Češće se javlja kod starijih osoba, žena, osoba koje su izložene niskoj vlažnosti zraka, osoba s autoimunim poremećajima, ali i kod mlađih osoba zbog svakodnevne dugotrajne uporabe digitalnih uređaja. Kationske nanoemulzije sa svojstvom mukoadhezivnosti stupaju u kontakt s mucinima na površini oka i namijenjene su liječenju bolesti površine oka zbog duljeg zadržavanja lijeka i veće bioraspoloživosti. U liječenju simptoma blagog oblika bolesti suhog oka dobre rezultate pokazuju kationske nanoemulzije pripravljene od sastavnica sličnih onima koje su fiziološki prisutne na površini oka. U sklopu ovog diplomskog rada uspješno su pripravljene formulacije koje sadrže 2,5% (m/m) polusintetske smjese srednjelančanih triglicerida, 0,05% (m/m) lecitina, 0,25% (m/m) makrogolglicerol ricinoleata 35, 0,05% (m/m) kitozana – polusintetskog kationskog polimera sa svojstvom mukoadhezivnosti, 2,5% (m/m) glicerola – alkohola neutralnog naboja prikladnog za izotonizaciju nanoemulzija i pročišćenu vodu do 100% (m/m). Pripravljenim formulacijama ispitana su fizičko-kemijska svojstva: prosječna veličina, raspodjela veličina te zeta-potencijal kapljica unutarnje faze. Također, ispitano je svojstvo mukoadhezivnosti reološkom metodom te određivanjem veličine kapljica, raspodjele veličina kapljica i zeta-potencijala nanoemulzija nakon miješanja s mucinom. Na temelju provedenih ispitivanja kao formulacija s potencijalom za daljnji razvoj ističe se sekundarna kationska nanoemulzija s oligomerom kitozana pripravljena dodavanjem otopine oligomera kitozana u smjesu prije priprave nanoemulzije procesom mikrofluidizacije. Dry eye disease is an ocular surface disease common in present times, more expressed in certain populations, such as senior citizens, women, people exposed to low humidity, patients with autoimmune diseases as well as younger people due to excessive everyday use of digital devices. Cationic nanoemulsions of mucoadhesive properties interact with mucins on the ocular surface and are intended for treatment of ocular surface diseases due to longer retention time of the drug and consequently its greater bioavailability. In treating symptoms of mild form of dry eye disease, cationic nanoemulsions composed of components similar to those found as constituents of the ocular surface show good results. Formulations prepared for purposes of this diploma thesis are composed of 2.5% (w/w) semisynthetic mixture of middle chain fatty acids, 0.05% (w/w) lecithin, 0.25% (w/w) macrogolglycerol ricinoleate 35, 0.05% (w/w) chitosan – semisynthetic cationic polymer with mucoadhesive properties, 2.5% (w/w) glycerol – neutrally charged alcohol suitable for nanoemulsion isotonisation and purified water to 100% (w/w). Formulations were tested for their physicochemical properties: average size, size distribution as well as zeta-potential of droplets of inner phase of nanoemulsions. In addition, mucoadhesive properties were also tested using rheological method and by measuring droplet size, size distribution and zeta-potential of nanoemulsions after the addition of mucin. Based on all conducted tests, formulation showing the potential for further development is secondary cationic nanoemulsion with chitosan oligosaccharide formed by adding a solution of chitosan oligosaccharide to the mixture before the process of microfluidisation.
- Published
- 2022
7. Razvoj oftalmičkih sekundarnih kationskih nanoemulzija za uklapanje slabo topljivih glukokortikoida
- Author
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Pavić, Klara and Lovrić, Jasmina
- Subjects
lecitin ,tyloxapol ,macrogol 15 hydroxystearate ,Kationska nanoemulzija ,Bolest suhog oka ,Kitozan ,Lecitin ,Polisorbat 80 ,Makrogol 15 hidroksistearat ,Tiloksapol ,tiloksapol ,dry eye disease ,makrogol 15 hidroksistearat ,BIOMEDICINE AND HEALTHCARE. Pharmacy. Pharmacy ,kationska nanoemulzija ,lecithin ,polisorbat 80 ,kitozan ,cationic nanoemulsion ,bolest suhog oka ,polysorbate 80 ,chitosan ,BIOMEDICINA I ZDRAVSTVO. Farmacija. Farmacija - Abstract
Nanoemulzije se ističu kao inovativni farmaceutski oblik s velikim potencijalom u liječenju bolesti suhog oka. Prednosti nanoemulzija temelje se na njihovoj strukturi i sastavu koje imaju učinak nadomještanja i stabilizacije suznog filma te na mogućnosti uklapanja slabo topljivih gluokokoritikoida kao što je loteprednol etabonat, djelatna tvar nedavno odobrena u liječenju blagih do umjerenog oblika bolesti suhog oka. Poseban potencijal imaju kationske nanoemulzije, zbog dobrih svojstava širenja po površini oka pri primjeni te produljenom zadržavanju na površini oka. Cilj ovog diplomskog rada bio je razviti sekundarnu kationsku U/V nanoemulziju s kitozanom pogodnu za uklapanje loteprednol etabonata. Nanoemulzije U/V tipa izrađene su visokoenergetskom metodom mikrofluidizacije. Kao ulja faza odabran je Capryol 90 zbog dobre topljivosti loteprednol etabonata u toj uljnoj fazi. Razvoj nanoemulzije proveden je u tri faze, (i) probir vrste i udjela neionske površinski aktivne tvari, (ii) probir vrste i udjela anionske površinski aktivne tvari te (iii) probir udjela niskomolekulskog kitozana. U svih fazama razvoja provedena je fizičko-kemijska karakterizacija nanoemulzija u vidu određivanja veličine i raspodjele veličina kapljica disperzne faze te zeta-potencijala. Na temelju provedene fizičko-kemijske karakterizacije sekundarna kationska nanoemulzija s 0,05 % (m/m) kitozana, 5 % (m/m) Capryola® 90, 0,25% (m/m) makrogol 15 hidroksistearata i 0,1% (m/m) lecitina Lipoid S75 ističe se kao vodeća formulacija s najvećim potencijalom za uklapanje loteprednol etabonata. Nanoemulsions stand out as an innovative dosage form with great potential in the treatment of dry eye disease. The benefits of nanoemulsions are based on (i) their structure and composition, which have the effect of replacing and stabilizing the tear film; and (ii) the ability to incorporate poorly soluble glucocorticoids such as loteprednol etabonate, an active substance recently approved in the treatment of mild to moderate dry eye disease. Cationic nanoemulsions have a unique potential due to their good spreading properties on the eye surface and prolonged retention on the eye surface. The aim of this thesis was to develop a secondary cationic O/W nanoemulsion with chitosan suitable for the incorporation of loteprednol etabonate. O/W type nanoemulsions are prepared by microfluidization. Capryol® 90 was chosen as the oil phase due to the good solubility of loteprednol etabonate in this oil phase. The development of the nanoemulsion was carried out in three phases, (i) screening of the type and content of nonionic surfactants, (ii) screening of the type and content of anionic surfactants, and (iii) screening of the content of low molecular weight chitosan. In all phases of development, physicochemical characterization of nanoemulsions was performed in the terms of determining the size and size distribution of droplets of the dispersed phase and zeta potential. Based on the performed physicochemical characterization, the secondary cationic nanoemulsion with 0.05% (w/w) chitosan, 5% (w/w) Capryola® 90, 0.25% (w/w) macrogol 15 hydroxystearate and 0.1% (w/w) Lecithin Lipoid® S75 stands out as the leading formulation with the greatest potential for incorporation of loteprednol etabonate.
- Published
- 2022
8. Razvoj funkcionalnih kationskih nanoemulzija za liječenje bolesti suhog oka
- Author
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Jurišić Dukovski, Bisera and Lovrić, Jasmina
- Subjects
lecitin ,stearylamine ,porcine cornea ,Pharmacology. Therapeutics. Toxicology ,dry eye disease ,rožnica svinje ,udc:615(043.3) ,BIOMEDICINE AND HEALTHCARE. Pharmacy. Pharmacy ,kationska nanoemulzija ,suho oko ,dry eye ,lecithin ,bolest suhog oka ,stearilamin ,kitozan ,ibuprofen ,3D HCE-T model ,cationic nanoemulsion ,Farmakologija. Terapeutika. Toksikologija ,chitosan ,BIOMEDICINA I ZDRAVSTVO. Farmacija. Farmacija - Abstract
Bolest suhog oka je multifaktorijalna bolest koju karakterizira nestabilnost i hiperosmolarnost suznog filma te upala površine oka. Kationske nanoemulzije tipa ulje u vodi (U/V) predstavljaju napredak u liječenju bolesti suhog oka služeći kao tehnološka platforma za uklapanje slabo topljivih djelatnih tvari, omogućujući pritom njihovo produljeno zadržavanje na površini oka te istodobnu nadoknadu i stabilizaciju narušenog suznog filma. Cilj ovog doktorskog rada je razvoj funkcionalne kationske nanoemulzije za liječenje bolesti suhog oka. U tu su svrhu pripravljena dva tipa nanoemulzija korištenjem mikrofluidizatora: primarne kationske nanoemulzije sa stearilaminom i sekundarne kationske nanoemulzije s kitozanom. Primarne kationske nanoemulzije s rastućim udjelima stearilamina male su veličine kapljica (< 100 nm), primjerene disperznosti (PDI ≤ 0,25), pozitivnog zeta-potencijala (3,1-25,5 mV), prikladne pH vrijednosti, male viskoznosti i površinske napetosti 31,3-35 mN m-1. Pripravljene nanoemulzije stabilne su tijekom petomjesečne pohrane. Nakon miješanja s disperzijom mucina zapažene su promjene u veličini kapljica i zeta-potencijalu koje ukazuju na interakciju s mucinom. Takve promjene nisu bile izraženije s povećanjem udjela stearilamina na više od 0,05 % (m/m). Vijabilnost 3D HCE-T modela iznosila je najmanje 90 % nakon izlaganja pripravljenim formulacijama. Sekundarne kationske nanoemulzije pripravljene s manjim (NC1: 0,05 %, m/m) i većim (NC2: 0,3 %, m/m) udjelom kitozana veličine su kapljica približno 180 nm, veće homogenosti (PDI < 0,2) i pozitivnog zeta-potencijala (18,7 i 30 mV). Iako je formulacija NC1 pokazala bolju stabilnost, ibuprofen je uspješno uklopljen u obje formulacije (INC1 i INC2). Fizičkokemijska svojstva (pH, viskoznost, osmolarnost i površinska napetost) pripravljenih formulacija unutar su raspona prikladnog za primjenu na oko. Formulacija INC1 stabilnija je od formulacije INC2 nakon jednomjesečne pohrane. Bakteriološka filtracija prikladna je metoda sterilizacije pripravljenih formulacija. Oslobađanje ibuprofena iz pripravljenih formulacija značajno je brže nego iz uljne otopine i suspenzije ibuprofena. Reološka karakterizacija formulacija pomiješanih s disperzijom mucina pokazala je njihov mukoadhezivni karakter koji, ipak, nije izraženiji kod formulacije INC2 s većim udjelom kitozana. Ispitivanja na 3D HCE-T modelu i ex vivo modelu rožnice svinje pokazala su izuzetnu biokompatibilnost INC1 formulacije. Uzimajući u obzir sve rezultate, nanoemulzija s 0,05 % (m/m) stearilamina i INC1 formulacija ističu se kao vodeće formulacije s velikim potencijalom za liječenje bolesti suhog oka. Dry eye disease is a multifactorial disease characterized by tear film instability and hyperosmolarity and ocular surface inflammation. Oil-in-water (O/W) cationic nanoemulsions represent a progress in dry eye disease treatment serving as a technological platform for incorporation of poorly soluble drugs, enabling prolonged residence time at the ocular surface and, at the same time, replenishment and stabilization of compromised tear film. The aim of this doctoral thesis is development of a functional cationic nanoemulsion for dry eye disease treatment. For this purpose two nanoemulsion types were prepared using microfluidizer: primary cationic nanoemulsions with stearylamine and secondary cationic nanoemulsions with chitosan. Primary cationic nanoemulsions with increasing stearylamine weight fraction are characterized with small droplet size (< 100 nm), low PDI (≤ 0.25), positive zeta-potential (3.1-25.5 mV), appropriate pH, low viscosity and surface tension 31.3-35 mN m-1. The nanoemulsions are stable after 5-month storage. Changes in nanoemulsion droplet size and zeta-potential were observed after mixing with mucin dispersion, which indicates interactions with mucin. However, the changes were not more pronounced with the increase in stearylamine weight fraction above 0.05 % (w/w). Viability of 3D HCE-T model was at least 90 % after exposure to the prepared formulations. Secondary cationic nanoemulsions prepared with low (NC1: 0.05 %, w/w) and high (NC2: 0.3 %, w/w) chitosan weight fraction are characterized with droplet size of around 180 nm, greater homogeneity (PDI < 0.2) and positive zeta-potential (18.7 and 30 mV). Although the formulation NC1 showed greater stability, ibuprofen was successfully incorporated in both formulations (INC1 and INC2). The physico-chemical properties (pH, viscosity, osmolarity and surface tension) of the prepared formulations are within the range acceptable for ophthalmic application. The formulation INC1 is more stable than the formulation INC2 after 1-month storage. Filtration is an appropriate sterilization method for the prepared formulations. Ibuprofen release from the prepared formulations is significantly faster than from ibuprofen oil solution and suspension. Rheological characterization of the formulations mixed with mucin dispersion showed their mucoadhesive character which, however, is not more pronounced with the formulation INC2 with higher chitosan weight fraction. The assays performed using 3D HCE-T model and ex vivo porcine cornea model showed remarkable biocompatibility of the formulation INC1. Taking everything into account, the nanoemulsion with 0.05 % (w/w) stearylamine and INC1 formulation point out as the lead formulations holding great potential for the treatment of dry eye disease.
- Published
- 2021
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