Preparatıon and Application of Biocompatible Carrier Implant to be Used in the Controlled Acquisition of Digoxin

Abstract

In this study, a persistent system is aimed to be established which contributes to slow basal digoxin release in the treatment of cardiac failure. Poly(2-hydroxyethyl-metacrylate-methylmetacrylate) (p(HEMA-MMA) copolymer that can swell by taking on water is prepared in cylindirical form by UV photopolymerization method for the controlled-release of digoxin and effective hydrogel implant formulation. A batch of p(HEMA-MMA) composition is prepared in different monomer ratios. Biocompatibility is improved by adding PEO, PEG and serum albumine to the structures of p(HEMA-MMA), respectively. Scanning electron microscope (SEM) studies are carried out for the surface structure of the prepared carrier implant material and differential scanning calorimetry (DSC) studies for the thermal stability analysis. Swelling behaviors are investigated by transferring solvent molecules to the hydrogels. Digoxin release kinetics are evaluated by applying three different accumulative digoxin doses (100, 250 and 500 U/mL) in the persistent flow release system containing physiological phosphate. Power law, level-zero, and Higuchi model equations are utilized so as to evaluate the release mechanism of digoxin. The most suitable results are acquired from the composition whose HEMA:MMA monomer ratio is 1:0.5 (v/v) in drug accumulation and release studies. It is observed from the SEM image that the carrier implant in the structure of the acquired hydrogel has a smooth surface. According to DSC results, it is seen that thermal stability decreases in the event that MMA comonomer is added to the structure of the pHEMA hydrogel. Balance water amount within the physiological phosphate buffer of the p(HEMA-MMA) copolymer is observed to be less than the pHEMA. Digoxin release loaded to carrier implants by different ratios takes a long-term period as expected. It is decided that the formulation established in the study can be successfully applied for the basal digoxin level over four weeks in the treatment of chronic cardiac failure.

Keywords

• pHEMA,p[HEMA-MMA]; Characterization; Digoxin; Controlled release

References

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