Journal of Hazardous Materials 401 (2021) 123782 Available online 1 September 2020 0304-3894/© 2020 Elsevier B.V. All rights reserved. Starch-Mg/Al layered double hydroxide composites as an efficient solid phase extraction sorbent for non-steroidal anti-inflammatory drugs as environmental pollutants Irshad Mohiuddin a, 1 , Aman Grover a, 1 , Jatinder Singh Aulakh a, **, Ashok Kumar Malik a , Sang Soo Lee b , Richard J.C. Brown c , Ki-Hyun Kim d, * a Department of Chemistry, Punjabi University, Patiala 147002, Punjab, India b Department of Environmental Engineering, Yonsei University, Wonju 26493, Republic of Korea c Environment Department, National Physical Laboratory, Teddington TW11 0LW, UK d Department of Civil and Environmental Engineering, Hanyang University, Seoul 04763, Republic of Korea A R T I C L E INFO Editor: Rinklebe J¨ org Keywords: Starch Layered double hydroxide Morphology Thermal stability NSAIDs ABSTRACT Using a co-precipitation method, starch-Mg/Al layered double hydroxide (S-Mg/Al LDH) composites were syn- thesized. Their physicochemical properties were assessed by Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and thermo-gravimetric analysis. The quantification of six non- steroidal anti-inflammatory drugs (NSAIDs) was conducted using real samples (e.g., hospital waste water, river water, sewage treatment plant water, and tablet formulations) by gas chromatography-mass spectrometry. For the development of this method, the system was optimized in terms of several key variables (e.g., pH, flow rate, and eluent type/volume). The developed method for NSAIDs exhibited good resolution, sensitivity, reproducibility, and specificity even in complex matrices with limits of detection between 4 and 20 pg/mL. Hence, S-Mg/Al LDH composites were proven to be efficient and fast solid phase extraction (SPE) sorbents for NSAIDs. In addition, each LDH-SPE cartridge showed good reusability without a noticeable change in perfor- mance (e.g., up to 30 cycles) and target recoveries between 99.5 – 82.9 %. This work should open up new opportunities for a sesnsitive and sustainable quantitative method for the determination of NSAIDs in complex samples. 1. Introduction The release of pharmaceuticals into the environmental systems is recognized as a significant threat to the environment (Patel et al., 2019). Environmental residues of pharmaceuticals in fact exert both chronic and acute effects on ecological systems even at low concentrations (Patel et al., 2019). Non-steroidal anti-inflammatory drugs (NSAIDs) are well-known for their effectiveness in treating diverse diseases (e.g., analgesic, antipyretic, and anti-inflammatory actions) (Rodrí- guez- ´ Alvarez et al., 2013; Schemeth et al., 2016). As NSAIDs are the most frequently used therapeutic agents both by prescription and by self-medication without a prescription, they are frequently detected in the aquatic systems (Manrique-Moreno et al., 2016; Hughes et al., 2013). Because of stability and hydrophilicity, certain NSAIDs (e.g., naproxen (NPX)) are reported to remain over a prolonged time (Patel et al., 2019). They are reported to exist in surface waters at concentra- tions of a few ng/L to as high as mg/L levels (Brun et al., 2006; Gupta et al., 2009; Manzo et al., 2014). Further, mixtures of NSAIDs are known to exhibit toxic effects that are rather different from their individual pharmaceuticals (Cleuvers, 2004). The development and employment of reliable analytical techniques are crucial for proper quantification of pharmaceutical compounds in various matrices (Fatta-Kassinos et al., 2011; Rivera-Utrilla et al., 2013). In this respect, many research efforts have been directed at designing and implementing analytical techniques for NSAIDs with high selec- tivity, low detection limits, and stoichiometric extraction efficiencies. * Corresponding author. ** Corresponding author. E-mail addresses: chemiaulakh@gmail.com (J.S. Aulakh), kkim61@hanyang.ac.kr (K.-H. Kim). 1 These authors contributed equally as first author. Contents lists available at ScienceDirect Journal of Hazardous Materials journal homepage: www.elsevier.com/locate/jhazmat https://doi.org/10.1016/j.jhazmat.2020.123782 Received 26 May 2020; Received in revised form 15 August 2020; Accepted 20 August 2020