The Study On Eye Drops Of Recombinant People Thymus Pigmentβ4 Thermo-sensitive Gel

Objective:Dry eye syndrome,one of the highest incidence of ocular diseases in the eye,is a kind of ocular surface diseases caused by various ocular disorders of function and protection mechanism,which could lead to ocular discomfort,visual disturbance and unstable tear film.Recombinant people thymus pigment β 4(rh-Tβ4)could be used to treat heavy degrees dry eye syndrome.In order to enhance the stability and effectiveness and extend storage life of rh-Tβ4,we prepared rh-Tβ4-hydroxyl-3-cyclodextrin thermo-sensitive sustained release gel,aiming to develop a quality stable,controllable,clinically secure,and effective rh-Tβ4 eye drops.Methods:Freeze-drying method was employed to prepare rh-TB4-hydroxyl-β-cyclodextrin,and further condensation method was employed to prepare thermo-sensitive sustained release gel using Pluronic 407(P-407)and Pluronic 188(P-188)as gel matrix materials.Fourier transform infrared spectrum method and differential scanning calorimetry were used to identify the formation of inclusion complex.The rate of inclusion and quality standard of rh-Tβ4-hydroxyl-β-cyclodextrin thermo-sensitive sustained release gel were determined by high performance liquid chromatography(HPLC).The gel stability and in vitro release were also measured according to content determination.0.3%benzalkonium chloride was used to construct dry eye syndrome model of rats.The successful models were randomly divided into six groups and continuously administrated for seven days.Irritation and preliminary efficacy were evaluated by fractured lamp photography,sodium fluorescein dye score,tear secretion,tear film rupture time,HE pathology check and electron microscopeResults:Through infrared spectrum and the DSC analysis,we confirmed the formation of inclusion complex.Rate of inclusion was 98%according to HPLC results.The optimal preparation conditions were as followed:drug:cyclodextrin=1:10,2 h mixing time,16%of P 407 and 14%of P 188,and 36℃ gelation temperature.rh-Tβ4-hydroxyl-β-cyclodextrin thermo-sensitive sustained release gel presented less viscosity at room temperature.But after dropping into the eye,with temperature increasing,the viscosity has increased to form a gel.In vitro release results showed that compared with rh-β4,rh-β4-β-cyclodextrin inclusion complexes and rh-Tβ4-hydroxyl-β-cyclodextrin thermo-sensitive gel had sustained-release characteristics.Stability test showed that,the stability of rh-Tβ4-hydroxyl-β-cyclodextrin thermo-sensitive gel was superior to rh-Tβ4.Preliminary efficacy experiment showed that rh-Tβ4-hydroxyl-β-cyclodextrin thermo-sensitive gel had on irritation on eye and it could promote healing,which showed good effect on dry eye syndrome treatmentConclusion:Preparation process of rh-Tβ4-hydroxyl-β-cyclodextrin thermo-sensitive gel was simple.Compared to rh-Tβ4,rh-Tβ4-hydroxyl-β-cyclodextrin thermo-sensitive gel was more stable,higher bioavailability,quality controllable.Method for the content determination was simple,highly accurate,fine repeatability.Therefore,it can be used for the quality control of the gel.