Encapsulation of biological stains for drug delivery imaging and microscopy in dentin tubules (733.6)

Abstract

Encapsulation of Biological Stains for Drug Delivery Imaging and Microscopy in Dentin Tubules Michael Lau1, Ridwan Haseeb1, Francisco Montagner2, Danieli Rodrigues1: 1Department of Bioengineering, University of Texas at Dallas, Richardson, TX; 2Department of Conservative Dentistry, Federal University of Rio Grande do Sul, Brazil; Introduction: Bacteria are able to remain into dentin after the root canal disinfection. Drug penetration into the tubules can be a key component for infection control. This study uses the synthesis of poly(ethylene glycol)‐block‐poly(L‐lactide) PEG/PLA encapsulated biological stain particles to characterize the penetration depth of drug delivery systems with Confocal Laser Scanning Microscopy (CLSM). Methodology: Encapsulation of the biological stain was done with an oil‐water emulsion‐evaporation technique. The PEG/PLA copolymer and the stain were dissolved in the oil phase while the surfactant was dissolved in water. The oil phase and water phase was combined and emulsified then stirred. The particles were centrifuged, washed, and lyophilized. Characterizing the particle size and fluorescence was done with CLSM (VK‐X200 Keyence Laser Scanning Microscope). Results: The microscopy has shown particle formation in the 0.3‐1.0 m range, which depended on the method of emulsification: homogenizing or sonication. CLSM revealed that the particles fluoresce under light with 525‐605 nm wavelengths. Conclusion: The encapsulation technique effectively encapsulated the biological stain to penetrate the dentin tubules. With particle size similar to dentin morphology, the encapsulated stain proliferation into the dentin tubules will model dentin penetration of drug delivery systems of similar size.