The Fourth Symposium on Innovative Polymers for Controlled Delivery (SIPCD 2016): Conference Abstracts Design of pH-responsive albumin-alginate hydrogels for drug delivery Kamila A.L. de Oliveira, Danielly L.A. Sitta, Marcos R. Guilherme, Edvani C. Muniz, Adley F. Rubira ⁎ Department of Chemistry, State University of Maringá, Av. Colombo, 5790, CEP 87020-900, Maringá, Paraná, Brazil ⁎Corresponding author. E-mail address: afrubira@uem.br (A.F. Rubira) Hydrogels are composed of polymer networks held together by physical and/or chemical bonds that can absorb up to 2,000 g of water per gram of dry polymer. Hydrogels made from natural polymers were shown to be compatible with cells and non-antigenic. They can be engineered to be used in a broad array of biomedical applications such as tissue implants, contact lenses, artificial muscles, and drug delivery [1,2]. This work aimed at creating a hydrogel from alginate and albumin for drug delivery. Prednisolone was used as a model drug. Albumin is a protein compatible with blood, plasma and other components of body and able to bind reversibly to a wide diversity of substances. Alginate is an anionic, biocompatible, and cell-adhesive polysaccharide. To achieve effective chemical crosslinking, alginate and albumin were modified with glycidyl methacrylate (GMA) and maleic anhydride (MAY), respectively. Hydrogel were prepared by cross-linking/ polymerization of GMA-alginate and MAY-albumin in water using sodium persulfate as a initiator and N,N,N',N-tetramethylethylenediamine (TEMED) as a catalyst at room temperature. The solution turned to stiff, transparent gel within 5 min. These albumin-alginate hydrogels demon- strated a pH-responsive behavior. The release of prednisolone from the hydrogels in PBS aqueous buffer at pH 7.4 followed a pseudo-Fickian mechanism. Keywords: drug delivery, hydrogels, natural polymers, pH-sensitivity Acknowledgements This work is financially supported by following Brazilian gov- ernment agencies: CNPq, CAPES, F.Araucária, MCTI-FINEP/Skintech Technology Proc. 0313028100. References [1] A. S. Hoffman, Hydrogels for biomedical applications. Adv. Drug Deliv. Rev. 43 (2002) 3-12. [2] M. P. Lutolf, P. M. Gilbert, Helen M. Blau, Designing materials to direct stem-cell fate. Nature 462 (2009) 433-441. [3] F. Iemma, U. G. Spizzirri, F. Puoci, G. Cirillo, M. Curcio, O. I. Parisi, N. Picci. Synthesis and release profile analysis of thermo-sensitive albumin hydrogels. Colloid Polym. Sci. 2009, 287 (7), 779-787. doi:10.1016/j.jconrel.2017.03.043 CXCR4-targeted combination therapy for the treatment of liver fibrosis Aftab Ullah a , Kaikai Wang a , Gang Chen a , Yiwen Zhou a , Ling Ding a , Qi Hu a , David Oupický a , b , ⁎ a Department of Pharmaceutical Sciences, China Pharmaceutical University, Nanjing 210028, China b Center for Drug Delivery and Nanomedicine, University of Nebraska Medical Center, Omaha, NE 68198, USA ⁎Corresponding author at: Department of Pharmaceutical Sciences, China Pharmaceutical University, Nanjing 210028, China. E-mail address: david.oupicky@unmc.edu (D. Oupický) Liver fibrosis is the consequence of a sustained wound-healing response to chronic liver injury. Progressive liver fibrosis leads to cirrhosis and hepatocellular carcinoma [1]. SDF1-α interacts with CXCR4 receptors on quiescent hepatic stellate cells and activates them. The activation of hepatic stellate cells (HSCs) leads to the increased HSCs population, proliferation, and collagen I production [2]. The activated HSCs are the main collagen-producing cells in the injured liver and are the main cause of liver fibrosis. Thus, inhibition of the activation of HSCs can be a useful strategy in reversing hepatic fibrosis [3]. The objective of this study was to design CXCR4-receptor targeted liposomes loaded with Plerixafor (AMD3100) and Pirfenidone for the combination therapy of liver fibrosis (Fig. 1). The targeting ability of the prepared liposomes was confirmed by whole-body bio- imaging analysis. High-content analysis was applied to quantify the CXCR4 antagonistic activity of the prepared liposomes. Carbon tetra- chloride (CCl 4 )-induced liver fibrosis mouse model was established and Fig. 1. Preparation of albumin-alginate hydrogels. a′ depicts the vinylated alginate and b′, b′′ and b′′′ depicts the different products from reaction between albumin and MAY [3]. 0168-3659/$ – see front matter Journal of Controlled Release 259 (2017) e5–e195 Contents lists available at ScienceDirect Journal of Controlled Release journal homepage: www.elsevier.com/locate/jconrel