IADR Abstract Archives
Effect of Crosslinking on Thiol-ene Microparticle Drug Delivery
Objectives: There is a need for local drug delivery systems in dentistry due to many dental procedures requiring localized treatment. Microparticles made using thiol-ene polymerization are promising for use as local drug delivery systems. Thiol-ene polymerization has advantages such as fast reaction rates, high yields, eco-friendly products, and perfect crosslinking structures; making microparticles made using thiol-ene polymerization suitable for use as drug delivery systems. Crosslinking influences a polymer’s properties hence our study investigates the impact of increased crosslinking using pentaerythritol tetra(3-mercaptopropionate) (PEMP) on thiol-ene microparticle drug release behavior.
Methods: We increased the mole ratio of our crosslinking agent, PEMP, to the monomer used in the thiol-ene reaction, (2-thiol) from 90:10 to 100:0 in two groups: F1 (90:10 alkene: surfactant ratio) and F2 (80:20 alkene: surfactant ratio). Both groups were pre-soaked in 20 and 50 mg/mL solution of a broad-spectrum antibiotic, doxycycline hyclate. Doxycycline release from the microparticles placed in PBS was measured using UV-vis spectroscopy for 5 days. Statistical analysis was performed using one-way ANOVA.
Results: Increased crosslinking only affected drug release behavior of formulations pre-soaked in 20 mg/mL doxycycline hyclate solution: The F1 groups showed an increased amount of drug released only for the PEMP:2-thiol ratio of 96:4, where a 21% increase was observed compared to 90:10 formulation. Other formulations (92:8, 94:6, 98:2, 100:0) showed lower drug release amounts than the 90:10 formulation. In F2 groups, increasing the PEMP:2-thiol ratio lowered the amount of drug released, with the 90:10 formulation releasing the highest amount of doxycycline. No statistically significant differences were observed in the drug release behavior of the 50 mg/mL doxycycline pre-soaked F1 and F2 groups with increasing PEMP:2-thiol ratio.
Conclusions: At lower doxycycline loading, increasing crosslinking generally lowered the amount of drug released, indicating the potential for tunable drug delivery using thiol-ene microparticles in dental applications.
Methods: We increased the mole ratio of our crosslinking agent, PEMP, to the monomer used in the thiol-ene reaction, (2-thiol) from 90:10 to 100:0 in two groups: F1 (90:10 alkene: surfactant ratio) and F2 (80:20 alkene: surfactant ratio). Both groups were pre-soaked in 20 and 50 mg/mL solution of a broad-spectrum antibiotic, doxycycline hyclate. Doxycycline release from the microparticles placed in PBS was measured using UV-vis spectroscopy for 5 days. Statistical analysis was performed using one-way ANOVA.
Results: Increased crosslinking only affected drug release behavior of formulations pre-soaked in 20 mg/mL doxycycline hyclate solution: The F1 groups showed an increased amount of drug released only for the PEMP:2-thiol ratio of 96:4, where a 21% increase was observed compared to 90:10 formulation. Other formulations (92:8, 94:6, 98:2, 100:0) showed lower drug release amounts than the 90:10 formulation. In F2 groups, increasing the PEMP:2-thiol ratio lowered the amount of drug released, with the 90:10 formulation releasing the highest amount of doxycycline. No statistically significant differences were observed in the drug release behavior of the 50 mg/mL doxycycline pre-soaked F1 and F2 groups with increasing PEMP:2-thiol ratio.
Conclusions: At lower doxycycline loading, increasing crosslinking generally lowered the amount of drug released, indicating the potential for tunable drug delivery using thiol-ene microparticles in dental applications.