soluble and materials bound microbial contaminations is shown [3]. Furthermore, test ... KETOPROFEN FOR THE TREATMENT OF. PERIODONTAL DISEASES.
POSTERS immune responses, independent of the actual intrinsic material properties. The laboratory conditions as well as the quality of the starting materials can be the reason for such biomaterial impurities [2]. Besides immune cells, also cells whose primary functions are not directly related to the immune system such as platelets, endothelial cells, or stem cells are responsive to endotoxins. Therefore, before new materials can be used for functional in vitro or in vivo tests, it has to be ensured that they are free of endotoxins and other biologically active contaminations, because such impurities may significantly bias the biological readout preventing a clear interpretation of the data. Here, a comprehensive immunological evaluation strategy for polymer-based biomaterials is presented, which not only aims to identify possible microbial contaminations but also intrinsic immunogenic or immunosuppressive material properties. A fast screening method using immune competent reporter cell lines, allowing the detection of soluble and materials bound microbial contaminations is shown [3]. Furthermore, test systems to investigate the potential of biomaterials to induced innate immune mechanisms such as the generation of reactive oxygen species and complement activation as well as methods to determine the material-induced activation of immune cells from human blood are presented. Biomaterials, which are proven to be free of immunologically active contamination and which have no intrinsic stimulatory properties, can be functionalized to induced distinct immune responses such as activation of dendritic cells, which are key players in the initiation and modulation of adaptive immune responses [4]. Furthermore, the determination of immunological properties of biomaterials should allow predicting the performance of the material in the human body and helps to interpret experimental in vitro and in vivo data. Acknowledgement: We thank the Bundesministerium f€ ur Bildung und Forschung (BMBF) for financing through project Poly4Bio (0315696A).
PLS-44 DEVELOPMENT AND EVALUATION OF EUGENOL NANOEMULGEL OF (S)KETOPROFEN FOR THE TREATMENT OF PERIODONTAL DISEASES Manish Srivastava*, Yubraj Neupane, Mushir Ali and Kanchan Kohli Hamdard University, Department of Pharmaceutics, New Delhi, India In the present study nanoemulgels (NEG) of (S)- Ketoprofen (KP) containing Eugenol as oil phase were developed not only to sustain the release but also to avoid first pass metabolism. The buccoadhesive gels were prepared by solution polymerization technique containing hydroxyl propyl methyl cellulose (HPMC) (E15 LV) and carbopol (CP) 934P. The NEGS were evaluated through particle size, zeta potential, viscosity, irritancy through vascular responses in the HAT- CAM study, buccoadhesive strength on goat buccal mucosa, in vitro release and permeation through dialysis membrane at pH 7.4. The swelling index was also determined for buccoadhesive gels. The drug excipient compatibility studies by Differential Scaning Spectroscopy and TLC assured Polym. Adv. Technol. 24 (Suppl. 1) 2013, 80–177
149 absence of any interference between the drug and excipients. The results showed that the best formulation with 1% HPMC and 1% CP assured the sustain release up to with t50% achieved in 10 hours and followed Higuchi kinetics with diffusion being the principle release mechanism.
PLS-45 CONCEPT FOR “REAL ENVIRONMENT” QUANTIFICATION OF SURFACE HYDROPHOBICITY OF POLYMERIC NANOPARTICLES Sven Staufenbiel1,2,*, Cornelia M. Keck1,2 and Rainer H. M€ uller1 1 FU Berlin, Biopharmaceutics & NutriCosmetics, Department of Pharmaceutics, Berlin, Germany; 2 PharmaSol GmbH, Berlin, Germany The surface hydrophobicity of polymeric nanoparticles in the body is one of the key parameters determining body distribution and biocompatibility. Examples: after i.v. injection, blood protein adsorption on the particle surface is determined by its hydrophobicity. The protein adsorption pattern determines the organ distribution, because the proteins mediate uptake by cells, e.g. by the MPS or target organs such as the brain. Adsorbed opsonins can reduce biocompatibility of s.c. injected particles by mediating macrophage interaction and inflammation reactions. Therefore it is important to quantify surface hydrophobicity as important characterization parameter. However, the problem is how to quantify correctly the hydrophobicity reflecting the original surface property in the aqueous environment. A frequently applied method measuring the contact angles on dried polymer nanoparticle films creates numbers irrelevant for the in vivo situation. For more thorough characterization of surface hydrophobicity a combination of 3 methods is suggested, i.e. Rose Bengal adsorption (RBA) studies, hydropbobic interaction chromatography (HIC) and aqueous two phase partitioning (TPP). The methods measure different aspects of surface hydrophobicity. Adsorption of the hydrophobic dye RB reflects specific interactions on the molecular structure level, which can be even more thoroughly assessed by using different dyes (different molecular interactions). HIC measures the ability of the particle surface to express hydrophobic interactions, e.g. with proteins. Some nanoparticle surfaces are extremely hydrophilic, RBA and HIC provide no sufficient resolution to differentiate. TPP between a dextran and polyethylene glycol (PEG) rich phase classifies relatively hydrophilic particles. RBA classifies hydrophobicity by the RB binding constant K, and the slope in a Scatchard plot of K versus particle concentration - it is an average measure of hydrophobicity, suitable to assess differences e.g. batch to batch variations or in particles made from the same monomer but differing in size. The elution profiles in HIC allow even to resolve subpopulations in hydrophobicity, e.g. in polymerized nanoparticles which are subsequently surface-modified, e.g. hydroxylated or fluorescently labeled. It can be assessed how many ª 2013 The Authors. Polymers for Advanced Technologies ª 2013 John Wiley & Sons, Ltd.
