Eudragit E100 and Polysaccharide Polymer Blends as Matrices for Modified-Release Drug Delivery I: Physicomechanical Properties

Purpose: To compare the effects of two states of polymer/polymer blending (dry and aqueous/lyophilized) on the physicomechanical properties of tablets, containing blends of locust bean gum (LB) with Eudragit® E100 (E100) and sodium carboxymethylcellulose (SCMC) as matrices.
Methods: LB, SCMC and E100 were blended in their dry (as purchased) state or modified by aqueous blending and subsequent lyophilization, prior to use as matrices in tablets. The polymer blends were characterized by infra-red spectroscopy (FTIR), flow and compressibility tests, as well as physicomechanical analysis of their tablets.
Results: No significant variations were noticeable in the FTIR peaks of the individual polymers in the dry and the aqueous/lyophilized states. Aqueous/lyophilized blending of the polymers resulted in better flow properties. The aqueous/lyophilized matrices were denser with improved mechanical strength and the tablets were harder than those produced from dry blended polymers.
Conclusion: Dry blending of LB with E100 and SCMC greatly improved the physicomechanical properties of the tablets. This was further enhanced by aqueous/lyophilized blending.

Keywords
Drug delivery; Polymer blend; Eudragit; Locust bean gum; Levodopa; Sodium carboxymethylcellulose; Matrix; Physicomechanical properties