Sensors and Actuators B 255 (2018) 1462–1470 Contents lists available at ScienceDirect Sensors and Actuators B: Chemical jo u r nal homep age: www.elsevier.com/locate/snb Construction of nanoparticles composite sensor for atorvastatin and its determination in pharmaceutical and urine samples Shikandar D. Bukkitgar a , Nagaraj P. Shetti a,∗ , Raviraj M. Kulkarni b a Electrochemistry and Materials Group, Department of Chemistry, K.L.E Institute of Technology, Affiliated to Visvesvaraya Technological University, Belagavi, Hubballi580030, Karnataka, India b Department of Chemistry, K.L.S Gogte Institute of Technology, Affiliated to Visvesvaraya Technological University, Belagavi 590008, Karnataka, India a r t i c l e i n f o Article history: Received 6 April 2017 Received in revised form 10 August 2017 Accepted 18 August 2017 Available online 30 August 2017 Keywords: Nano-silica Composite electrode Atorvastatin Electrochemical oxidation Reaction mechanism a b s t r a c t In the present work, first time a composite electrode based on nano-silica and zinc oxide nanoparticles were investigated for electrochemical determination of atorvastatin. The electrochemical behavior of atorvastatin at carbon paste electrode, initially modified with nano-silica was investigated. Further, the effect of addition of ZnO nanoparticles toward the electrochemical behavior of atorvastatin was studied and both were compared. The cyclic voltammetric peak current had a significant enhancement at nano- silica modified electrode as compared with the bare electrode. With addition of ZnO nanoparticles, it was observed that there was a large enhancement in the peak current as compared to that of nano- silica modified electrode. Parameters such as number of electrons transferred, diffusion coefficient, and heterogeneous rate constant were calculated. Limit of detection and quantification was calculated under the optimized conditions. For the analytical applications, pharmaceutical dose form and human urine sample analysis were performed. Various interferents were used to investigate the interference in the analytical application and was found that the proposed method would be well adopted for clinical trials and real sample analysis. © 2017 Elsevier B.V. All rights reserved. 1. Introduction Hyperlipidemia is a condition where abnormal elevated level of lipids occurs in blood. The most effective class of drugs used in the treatment is statins. Atorvastatin (ATR), belongs to the group statins and is chemically known as (3R, 5R)-7-[2-(4-fluorophenyl)-3-phenyl-4-(phenylcarbamoyl)-5- (propan-2-yl)-1H-pyrrol-1-yl]-3,5-dihydroxyheptanoic acid. In addition, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase is a key enzyme for cholesterol biosynthesis [1,2] and which has influenced on reducing triglycerides as well choles- terol [3–5]. ATR as anti-inflammatory is predominantly used in treatment of heart attack. In addition, heterozygous familial hypercholesterolemia in pediatric patients [6] is also treated with ATR. In 1985, Dr. Bruce D. Roth with Parke-Davis synthesized ATR and it is popularly marketed under various brand names in combination or single generic. The manufactures evaluate the quality of ATR using TLC or HPLC. Further, various reported methods are present for the drug determination, which involves ∗ Corresponding author. Tel.: +91 9611979743; fax: +91 0836 233068. E-mail address: dr.npshetti@gmail.com (N.P. Shetti). use of LC/MS [7,8], LC–ESI–MS/MS [9], HPLC–ES–MS/MS [10] and various spectrophotometry methods [11–13], adopted RP-HPLC [14,15], and other HPLC methods [16]. These proposed methods have low sensitivity, slow and expensive. Hence, it is essential to develop a method for the determination of ATR, which is less time consuming, simplified, and less expensive. Electrochemical meth- ods with these improved properties would be a good alternative source. A few electrochemical methods reported involved the use of adsorptive stripping voltammetry using glassy carbon electrode (GCE) [17,18] cyclic and differential pulse voltammetry (DPV) at a carbon paste electrode (CPE) in the presence of an enhancing agent, cetyltrimethyl ammoniumbromide (CTAB) [1] and DPV using boron-doped diamond electrode and GCE [19]. In the area of chemically modified electrodes, carbon paste elec- trodes (CPEs) have attracted a wide range of analyst in recent years. CPEs have unique advantages such as easiness in the preparation, various ligands depending on the application can be easily mixed during the paste preparation, cheaper, and low back ground cur- rent interferences during analysis [20,21]. These electrodes also promote open circuit accumulation of species proceeding to its voltammetric quantification. Organic polymers, ligands and inor- ganic ion exchangers such as clays or zeolite can be used as modifiers [22–24]. CPEs can easily prepared by mixing carbon http://dx.doi.org/10.1016/j.snb.2017.08.150 0925-4005/© 2017 Elsevier B.V. All rights reserved.