| To increase lipophility and stability, enhance ocularbioavailability, Zinc diethyldithiocarbomate (Zn-DDC), a prodrug of DDC, was prepared and identified. The physicochemical properties of Zn-DDC were studied. The results revealed that the prepared Zn-DDC sample was the same as control one. The solubility of Zn-DDC was 4.79g.ml-1, the O/W partition coefficient was 94.9+0.7.To increase its solubility and stability, enhance ocularbioavailability, Zn-DDC-HPpCD inclusion was prepared by milling method, agitating method and ultrasound method respectively and identified by DSC, IR and X-ray method separately. The results showed that the agitating method was suitable for the preparing of Zn-DDC-HPpCD inclusion, the solubility of Zn-DDC in the 10% HPpCD solution was 470 times than that in water, the stable constant of Zn-DDC-HPpCD inclusion was 3451.57 L.mol-1.A better formulation of Zn-DDC-HPpCD eye drops was selected by in vitro experiments. The components of the recipe were Zn-DDC(0.2%), HPPCD(8.0%), HPMC(0.1%), P188(1.0%), NaCl(0.9%) and BC (0.005%) individually.The pre-column derivation of DDC with P-BPB was used to the analysis for the aqueous humor samples and the pharmacokinetic process was studied. The results demonstrated that the concentration-time curves of DDC fit one compartment open model with first-order process. Compared with the 0.2%DDC eye drops and the 0.2% DSF eye drops , the bioavailability of the best formulation in ocular was increased 2.37 and 1.55 times respectively.The pharmacodynamics were studied by using Selenite-induced cataract rats and Hereditary Shumuya Cataract rats as models. The results indicated that the preparation had anti-cataract effect on both models (P<0.001). Compared to the control group, the concentration of Protein-SH in the lens was enhanced and the level of Ca2+ was decreased. The mechanism of inhibition of the cataract may be preventing the Protein-SH from oxidizing and maintain or revert to the normal physiological function.
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