The dispersions of sterile lyophilized NPs formulations in sterile

distilled water were used in this study having a concentration of 2.0% w/v DRZ. The rabbits were divided in to three groups. Each group composed of three rabbits. Group 1, Group 2, and Group 3 received OCM-CSNPs, CSNPs, and marketed formulations, respectively. For measuring the IOP, cornea of each rabbit was anaesthetized by instilling 50μL xylocaine (2% w/v) solution see more before administration of formulation. All rabbits received a single 50μL dose of NPs Inhibitors,research,lifescience,medical and marketed formulation onto the corneal surface of rabbit’s right eye. After instillation of formulation, the therapeutic efficacy of DRZ nanoparticles was assessed by measuring the IOP using a standardized Inhibitors,research,lifescience,medical tonometer (ShiØtz, Germany) [28]. IOP was measured after 30min of drug administration and then every 1 hour over the period of 8h. The left eye was left as a control in all the experimental animals. The ocular pressure lowering activity was expressed as average difference in IOP between the treated and control eye [29]. 2.3. Statistical Analysis Data are presented as the mean ± standard deviation. One-way analysis of variance (ANOVA) was performed followed by Dennett’s multiple Inhibitors,research,lifescience,medical comparisons to test the statistical significance.

The tests were performed by using GraphPad Prism version 6.01 for Windows, GraphPad Software (La Jolla CA, USA). 3. Results and Discussion 3.1. Synthesis of OCM-CS Percentage yield of OCM-CS in IPA alone gave low yield (48.62%) which may be attributed to the fact that CS was not alkalized in the nonaqueous solvent. The use of water alone Inhibitors,research,lifescience,medical as solvent lowers the yield even more (5.68%) owing to the easy

swelling of the previously formed OCM-CS in water to form jelly that coats the outside of the CS particle and inhibits the course of reaction. Therefore ratio of water/IPA was an important element for the successful completion of the reaction. Inhibitors,research,lifescience,medical The increase of the ratio of water/IPA in the reaction solvent decreases the fraction of carboxymethylation and increases the insolubility [15]. Similarly, when the effect of temperature on percent yield of OCM-CS was investigated, it was noted that the higher reaction temperature favoured the substitution of the carboxymethyl on the –OH group [14]. The highest yield 89.15% was obtained Bumetanide at 55°C (Table 2). Hence, 55°C temperature and solvent ratio H2O/IPA of 1/4 were considered optimum. 3.2. FT-IR Spectra of OCM-CS The basic characteristic peaks (Figure 1) of CS are at 3455cm−1 (O–H stretch), 2923–2867cm−1 (C–H stretch), 1598–1625cm−1 (N–H bend), and 1094cm−1 (C–O stretch). Compared with the peaks of CS, intense peak at 1734cm−1 in the IR spectrum of OCM-CS signifies the presences of –COOH group. The 1076cm−1 peak is attributable to C–O stretching of ether group of carboxymethyl moiety [30]. Figure 1 FT-IR spectrum of (a) CS and (b) OCM-CS. Intense peak at 1734cm−1 in the IR spectrum of OCM-CS signifies the presence of –COOH group.