ABSTRACT
Background Macrogol 15 hydroxystearate (HS15) is a novel soft non-ionic surfactant and is widely used to solubilize the poorly soluble drugs due to high drug loading and enhancing permeability ability to hydrophobic drug.However,the delivering effects to cornea of HS15 on terbinafine hydrochloride (TH),a insoluble antifungal agents,is unclear.Objective This study was to investigate the promoting corneal absorption effects of HS15 micelles (HNMs) on TH.Methods TH-HNMs was prepared by a co-solvent method.The hydrodynamic droplet size,polydispersity index,and Zeta potential of TH-HNMs were measured by using a Zetasizer.The shape of the micelles was observed under the transmission electron microscope.The high performance liquid chromatography (HPLC) was employed to detect the in vitro cumulative releasing level of TH in the TH-HNMs and drug entrapment efficiency.TH-HNMs was topically adninistered in eyes of 5 healthy male New Zealand rabbits to evaluate the ocular irritation response.Ninety rabbits were randomized into experimental group and control group,and 50 μl of 0.5％ TH-HNMs and 0.5％ oily TH were topically administered in the right eyes of the animals in the experimental group and contral group,respectively.The animals were sacrificed 5,15,30,60,90,120,180,240,360 minutes after eye dropping by over anesthetization way and the corneas were harvested,and the TH content in the cornea was detected using HPLC.The study protocal was approved by Life Science Ethic Committee of Henen Eye Hospital.Results The average size and polyolis persital index of TH-HNMs were 13.32 nm and 0.046,respectively,and its average Zeta potential was-0.133 mV.The drug entrapment efficiency was 100％.The release level of TH from the micelles presented a pH-dependent manner.The release level of TH was (95.20±3.20)％ in the phosphate buffer with pH 5.0 and (0.17± 0.01)％ in the phosphate buffer with pH 7.4.The ocular irritation score was 2,and no visible damage was found around experimental eyes after instillation of TH-HNMs.The peak content of TH in the rabbit cornea 5 minutes was (20.26±2.26)pg/g in the experimental group,which was significantly higher than (1.40± 0.44)μg/g in the control group (t =18.926,P=0.000).The area under the curve (AUC)0.360min of drug concentration-time curve in the experimental group was 1 292.25 μg/(g · min),which was 15.6 times more than the control group.Conclusions TH-HNMs is an ideal agent with a simple preparing process,high drug entrapment efficiency,small size and low ocular irritation.Compared with oily TH,TH-HNMs can effectively enhance the corneal absorption of TH.
ABSTRACT
Objective To observe the distribution and concentration of ~(125)I-nerve growth factor (NG-F) in rabbits' eyes after intravitreal injection and posterior juxtascleral injection.Methods Intravitreal injection(group A) and posterior juxtascleral injection (group B) were performed with the dosage of 30μg/100μl ~(125)I-NGF on left and right eyes in 45 white rabbits respectively.The γ-counts and the concentration of ~(125)I-NGF (%ID/g) of each ocular tissue was determined 15 and 30 minutes,and 1,3,6,12,24,and 48hours after injection.Results The ~(125)I-NGF diffusion in group A was faster in ocular content and ocular inner wall.The vitreous content of ~(125)I-NGF decreased gradually in group A,the curve changes in other eye tissues were normal.The concentration of ~(125)I-NGF reached the peak 3 hours after injection in aqueous humor,iris and ciliary body,retina,and choroids,but 6 hours after injection in sclera and 8 hours in cornea.The changes of concentration of ~(125)I-NGF in group B showed normal curve change.The peak time in group B were all 6 hours,in all the tissues except aqueous humor (3 hours).Except the high concentration in vitreous body caused by intravitreal injection,the concentration of ~(125)I-NGF in retina was the highest in group A.Conclusion Intravitreal injection of ~(125)I-NGF can gain higher concentration in each ocular tissue than posterior juxtaseleral injection,especially in retina.So intravitreal injection of NGF is a better ocular delivery method to treat the ocular fundus diseases.