In this work, fractional calculus approach is considered for modeling the viscoelastic behavior of human cornea. It is observed that the degree of both elasticity and viscosity is easy to describe in terms of the fractional order parameters in such approach. Modeling of the human cornea when subjected to simple stress up to the level of 250 MPa by Fractional order Maxwell Model along with the Fractional Kelvin Voigt Viscoelastic Model is reported. For the Maxwell governing fractional equation, two fractional parameters α and β have been considered to model the stress-strain relationship of human cornea. The analytical solution of the fractional equation has been obtained for different values of α and β using Laplace transform methods. The effect of the fractional parameter values on the stress-deformation nature has been studied. A comparison between experimental values and calculated values for different fractional order of the Maxwell model equation define the parameters which depicts the real time stress-strain relationship of human cornea. It has been observed that the fractional model converges to the classical Maxwell model as a special case for α = β = 1.

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The inherent properties of the healthy cornea, namely its strength, transparency and precise curvature enable it to withstand external injury and provides resistant to intraocular pressure, also allowing 95% transmission of incoming lightand providing 70% of the focusing power of the eye. Corneal transparency is dependent on the specific arrangement of collagen within the stroma. The research thrives for synthesis of a composite comprised of Collagen, the basic protein that can be abundantly found in human body and silica which is biosafe and biocompatible to physiological system and can act as a scaffold for tissue engineering and drug delivery. The starting materials of the synthesis are diluted Silica precursor and two types of collagen-I and III. Collagen type III is predominantly found on the epithelium and endothelium of the cornea which can enhance the mechanical property and optical property of the hybrid. Sol Gel technique has been applied for the synthesis of the composite and finally lyophilized after the pH has been stabilized around 7.2-7.4 to obtain dehydrated silica collagen composite. Optical property of the developed composite closely mimics the collagen hybrids from earlier work in this field. The composite exhibits crystallinity due to the presence of silica as it evidenced from its XRD plot. Other material characterizations, viz. FTIR and SEM have been performed on the sample to identify the microstructural nature of the composite.