Alpha-tricalcium phosphate cement: system for controlled release of antibiotic and local anesthetics

Abstract

Event Abstract Back to Event Alpha-tricalcium phosphate cement: system for controlled release of antibiotic and local anesthetics Julio C. Colpo1, 2, Caroline Pigatto1, Antoniella Ingrassia1, Luís A. Dos Santos1 and Teo Dick1 1 Federal University of Rio Grande do Sul, Laboratory of Biomaterials and Advanced Ceramics, Program Graduate in Mining, Metallurgical and Mate, Brazil 2 National Health Surveillance Agency, Health Surveillance Coordination, Brazil Introduction: It is a challenge develop new products of implantable drug delivery systems that can stimulate tissue growth at the same time they are absorbed produce appropriate and efficient therapeutic effects in treating various diseases. These products can minimize the risks related to the common side effects in conventional systems (oral and parenteral) as well as provide greater adherence to treatment, comfort and patient safety. Drug delivery systems of the α-TCP cement base can contribute to the maintenance of analgesia and antibiotics therapies. Its microstructure consists of nano-sized particles of hydroxyapatite provides a high loading of drugs, allowing its release for long periods. The aim of this study was to develop α-TCP cement systems added gentamicin sulfate, lidocaine chlorhydrate, bupivacaine chlorhydrate, levobupivacaine chlorhydrate, characterize them as their chemical and physical properties and investigate its viability as vehicles for controlled release of these drugs. Materials and Methods: Samples were produced with the addition of drugs and specimens free of drugs (control group). Specimens were prepared with the addition of drugs and specimens free of drugs (control group) and performed strength compression tests, determination of crystalline phases by X-ray diffraction (XRD), assessing microstructure by scanning electron microscopy and characterization of functional groups by infrared spectroscopy in Fourier Transform (FTIR). To release in vitro study the specimens (triplicate) were immersed in buffer and the samples taken at set periods. The release process was analyzed by UV-visible spectrophotometer. To investigate analytical differences between the groups was considered the confidence interval of 95% with significance level of 5% (p <0.05). Results and Discussion: The strength of study did not find significant differences between the control group and the other; The XRD patterns showed that the addition of drugs does not interfere with the curing reaction of the α-TCP cement; The similarities between the images showed that the different drugs present in the specimens did not interfere in the formation of crystals; The FTIR showed that the addition of the drugs did not interfere in the formation of hydroxyapatite. In the in vitro study the drugs were released from controlled way. It was observed that the drug contained in the specimens were dispersed in the buffer solution from the first hours of the start of the study (2 to 4 hours), with a more intense release up to 48 hours. Conclusions: Data analysis enabled us to identify that the heterogeneity between groups of different drugs did not affect significantly the Properties of α-TCP cement compared to the control group. The α-TCP cement served as a reservoir system (drugs were incorporated in its structure) and regulator of the drug release rate. Wherefore, the data demonstrate the viability of using the α-TCP cement system to the drugs release. Cristália Produtos Químicos Farmacêuticos Ltda; Instituto de Química/UFRGS; LAPOL/UFRGS; LACER/UFRGS