Biogenic platinum and palladium nanoparticles as new catalysts for the removal of pharmaceutical compounds M  onica Martins a, * , Cl  audia Mourato a , Sandra Sanches b , Jo ~ ao Paulo Noronha c , M.T. Barreto Crespo a, b , In ^ es A.C. Pereira a, ** a ITQB NOVA, Instituto de Tecnologia Química e Biol ogica Ant onio Xavier/ Universidade Nova de Lisboa, Av. da Republica-EAN, 2780-157 Oeiras, Portugal b iBET, Instituto de Biologia Experimental e Tecnol ogica, Apartado 12, 2780-901 Oeiras, Portugal c LAQV, REQUIMTE, Departamento de Química, Faculdade de Ci^ encias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal article info Article history: Received 26 July 2016 Received in revised form 25 October 2016 Accepted 27 October 2016 Available online xxx Keywords: Pharmaceutical compounds Biogenic nanoparticles Platinum Desulfovibrio Reductive catalysis abstract Pharmaceutical products (PhP) are one of the most alarming emergent pollutants in the environment. Therefore, it is of extreme importance to investigate efficient PhP removal processes. Biologic synthesis of platinum nanoparticles (Bio-Pt) has been reported, but their catalytic activity was never investigated. In this work, we explored the potential of cell-supported platinum (Bio-Pt) and palladium (Bio-Pd) nano- particles synthesized with Desulfovibrio vulgaris as biocatalysts for removal of four PhP: ciprofloxacin, sulfamethoxazole, ibuprofen and 17b-estradiol. The catalytic activity of the biological nanoparticles was compared with the PhP removal efficiency of D. vulgaris whole-cells. In contrast with Bio-Pd, Bio-Pt has a high catalytic activity in PhP removal, with 94, 85 and 70% removal of 17b-estradiol, sulfamethoxazole and ciprofloxacin, respectively. In addition, the estrogenic activity of 17b-estradiol was strongly reduced after the reaction with Bio-Pt, showing that this biocatalyst produces less toxic effluents. Bio-Pt or Bio-Pd did not act on ibuprofen, but this could be completely removed by D. vulgaris whole-cells, demonstrating that sulfate-reducing bacteria are among the microorganisms capable of biotransformation of ibuprofen in anaerobic environments. This study demonstrates for the first time that Bio-Pt has a high catalytic activity, and is a promising catalyst to be used in water treatment processes for the removal of antibiotics and endocrine disrupting compounds, the most problematic PhP. © 2016 Elsevier Ltd. All rights reserved. 1. Introduction The widespread occurrence of pharmaceutical products (PhP) in the environment has become a worldwide issue (Gavrilescu et al., 2015; Luo et al., 2014; Stuart et al., 2012). Globally, thousands of different active compounds are used in human and veterinary medicine and most of them are excreted in unaltered form or as active metabolites (Petrie et al., 2015). Due to their inefficient removal in wastewater treatment plants (WWTP) and improper disposal of industrial wastewaters, PhP are continuously intro- duced in the environment (Gavrilescu et al., 2015; Petrie et al., 2015). These pollutants are not only detected in wastewaters but also in surface waters, in sea and groundwater and even in drinking water in several countries (Gavrilescu et al., 2015; Luo et al., 2014; Stuart et al., 2012). Despite the low concentrations in which they are usually detected, their accumulation and persistence in the environment can lead to harmful effects on human and animal health and on the ecosystems (Gavrilescu et al., 2015; Luo et al., 2014; Stuart et al., 2012). The most problematic PhP are non-steroidal anti-inflammatory drugs, estrogens and antibiotics (Fischer et al., 2012; Santos et al., 2010). Estrogens are commonly found in aquatic systems, and there is strong evidence that they affect the fertility and develop- ment of fish, reptiles and aquatic vertebrates (Boxall, 2004; Santos et al., 2010). Antibiotics are also a severe environmental problem because even at vestigial levels they can induce resistance in bac- terial populations (Gavrilescu et al., 2015). To prevent environmental contamination by PhP and their possible adverse effects, it is essential to develop new strategies to remove these pollutants from wastewaters. Advanced oxidation processes, such as UV/H 2 O 2 , UV/O 3 , and UV/TiO 2 , have been the most studied processes for PhP degradation (Homem and Santos, * Corresponding author. ** Corresponding author. E-mail addresses: msmartins@itqb.unl.pt (M. Martins), ipereira@itqb.unl.pt (I.A.C. Pereira). Contents lists available at ScienceDirect Water Research journal homepage: www.elsevier.com/locate/watres http://dx.doi.org/10.1016/j.watres.2016.10.071 0043-1354/© 2016 Elsevier Ltd. All rights reserved. Water Research xxx (2016) 1e9 Please cite this article in press as: Martins, M., et al., Biogenic platinum and palladium nanoparticles as new catalysts for the removal of pharmaceutical compounds, Water Research (2016), http://dx.doi.org/10.1016/j.watres.2016.10.071