chemical engineering research and design 1 1 2 ( 2 0 1 6 ) 56–63 Contents lists available at ScienceDirect Chemical Engineering Research and Design journal h om epage: www.elsevier.com/locate/cherd Investigation of different methods for cisplatin loading using single-walled carbon nanotube Amin Kazemi-Beydokhti b , Saeed Zeinali Heris a,* , Mahmoud Reza Jaafari c a Faculty of Chemical and Petroleum Engineering, University of Tabriz, Tabriz, Iran b Department of Chemical Engineering, School of Petroleum and Petrochemical Engineering, Hakim Sabzevari University, Sabzevar, Iran c Biotechnology Research Center, Nanotechnology Research Center, School of Pharmacy, Mashhad University of Medical Science, Mashhad, Iran a r t i c l e i n f o Article history: Received 23 November 2014 Received in revised form 14 March 2016 Accepted 4 June 2016 Available online 14 June 2016 Keywords: Single-walled carbon nanotube Cisplatin Encapsulation Surface functionalization Drug release rate a b s t r a c t Cisplatin as an anticancer drug is frequently used in cancer treatment, but with a lot of side effects. In this study, we investigated three different protocols of cisplatin drug loading inside and outside of single-walled carbon nanotube as a nano-platform. The drug encap- sulation, electrostatic interactions, and covalent binding of cisplatin were utilized in these complexes to evaluate the capability of drug–carrier interaction in each method. All nano- tube samples were dialyzed after preparation in phosphate buffer saline at acidic and neutral conditions for better simulation of tumor environments and then, the rate of drug release was determined using drug concentrations from the inside and outside of dialysis bags in the samples. Cisplatin showed the maximum and minimum rate of release for covalent and encapsulated complexes, respectively. Also, the amount of cisplatin drug release was quite different for two compounds at the beginning and at the end of dialysis. These trends of drug release in each of these drug loading approaches in different pH environments can help us to manage the optimized circulation time of cisplatin in the human body and the maximum release of drug at the target position. © 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. 1. Introduction Due to a large variety of physical and chemical properties of carbon nanostructures such as thermal, mechanical and electrical properties, it has widespread use as nanocarrier in various fields (Baughman et al., 2002; Bayazit and Kerkez, 2014; Dai, 2002; Li et al., 2013). Nanomedicine is one of this area, which has recently assigned a large part of this research (Kostarelos et al., 2009; Lacerda et al., 2006). Due to various shapes of these carriers like plane, cylinder and cone, different meth- ods of preparation have been applied to use it in medicine (Ajima et al., 2005; Pastorin et al., 2006; Sun et al., 2008a). Particle size and shape of nanocarriers can change the amount of drug loaded and drug release of complexes (Bahrami et al., 2014; Caldorera-Moore et al., 2010; Mudshinge et al., 2011). ∗ Corresponding author. Tel.: +98 411 33393158; fax: +98 511 8816840. E-mail addresses: a.kazemi@hsu.ac.ir (A. Kazemi-Beydokhti), s.zeinali@tabrizu.ac.ir (S. Zeinali Heris), Jafarimr@mums.ac.ir (M.R. Jaafari). Carbon nanotubes (CNT) as one of these nanocarriers have been proposed as an efficient nanoparticle for transportation of different drugs to the target site, especially malignant tumors. The high mechan- ical strength, suitable electrical, optical, thermal and kinetic properties are the advantages while the toxicity is the main disadvantage of CNTs (Kostarelos et al., 2009). Thermal property of CNT can use as an effec- tive parameter for thermal ablation of tumors (Chakravarty et al., 2008; Hashida et al., 2014; Kazemi-Beydokhti et al., 2015). The large num- ber of drug delivery systems based on CNTs were recently synthesized to apply these properties and overcome the side effects of anticancer drugs (Bhirde et al., 2010; Dhar et al., 2008; Madani et al., 2011; Ren et al., 2012). Some techniques like PEGylation and functionalization were used to control the inherent toxicity of the CNT (Campagnolo et al., 2013; Rodrigues et al., 2013; Zhang et al., 2011). http://dx.doi.org/10.1016/j.cherd.2016.06.006 0263-8762/© 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.