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A cryogel-based semi-interpenetrating polymer network (Cryo-SIPN) was prepared in which conductive polymers such as polyaniline (PANI) and polypyrrole (PPy) were formed within the super porous network of acrylic acid cryogel. For completion of cryo-polymerization, all the constituent solutions were severely mixed and placed into the plastic straws and kept at -20°C and then the synthesized cyrogels were cut into the 1-cm length and freeze dried after washing with water. The Cryo-SIPN polymeric composite was applied in micro solid phase extraction (µSPE) of some selected antibiotic residues from various samples. The µSPE method combined with a high performance liquid chromatography-ultraviolet (HPLC-UV) system allowed trace quantification of antibiotic residues in the honey and water samples while the significant variables were optimized using a central composite design (CCD) to find optimum conditions. The method performance was satisfactory with recovery ranges from 70.0 to 109%. The limits of detection (S/N = 3) and quantification (S/N = 10) for all samples were within the 17-50 μg kg -1 and 47-140 μg kg -1 range, respectively. The relative standard deviation was less than 10 % for antibiotics in the foodstuff and water samples. The validated Cryo-SIPN-µSPE in conjunction with HPLC-UV, proved to be versatile, efficient and robust while its capability toward the trace determination of drugs residues in real-life samples is demonstrated in this work., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

An imprinted interpenetrating polymer network (IPN) was synthesized and used as a medium for isolation of carbamazepine from urine samples. The polymer network consisted of a homogeneous polystyrene-sol gel hybrid constructed by in-situ radical polymerization method. In this process, within the sol-gel reaction duration, styrene monomer could penetrate into the reaction mixture and after the polymerization initiation, a monolithic IPN structure was prepared. The scanning electron microscopy (SEM) image and energy dispersive spectroscopy (EDX) are indications of the polystyrene dispersion at nano- to micro-meter level in the sol gel matrix. Eventually, the synthesized IPN was used as a sorbent in microextraction in packed syringe (MEPS) combined with high performance liquid chromatography (HPLC) for isolation of carbamazepine, naproxen and dexamethasone from urine samples. The molecularly imprinted IPN showed some degree of selectivity towards carbamazepine. To assess the important parameters influencing the extraction and desorption processes, an experimental design strategy was used. By the current method, low limits of detection (1.3-1.5μgL -1 ) and quantification (4.2-5μgL -1 ) were achieved (hydrocortisone as the internal standard). The intra- and inter-day precision data at 50 and 300μgL -1 were 1.3-7.4%, while the working linear dynamic range was from 4.2 to 500μgL -1 ., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A magnetic nanocomposite consisting of nanoparticles-polybutylene terephthalate (MNPs-PBT) was electrospun and used as an extracting medium for an on-line μ-solid phase extraction (μ-SPE)-high performance liquid chromatography (HPLC) set-up with an ultraviolet (UV) detection system. Due to the magnetic property of the prepared nanofibers, the whole extraction procedure was implemented under an external magnetic field to enhance the extraction efficiencies. The developed method along with the synthesized nanocomposite were found to be appropriate for the determination of trace levels of selected drugs including furosemide, naproxen, diclofenac and clobetasol propionate in the urine sample. The prepared MNPs-PBT electrospun nanocomposite was characterized using the scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and Fourier transform infrared (FT-IR) spectroscopy. The prepared magnetic fibers showed high porosity, which was another driving force for the extraction efficiency enhancement. Major parameters affecting the extraction efficiency of the selected drugs were optimized. The limits of detections (LOD) of the studied drugs were in the range of 0.4-1.6 μg L(-1) and the limits of quantification (LOQ) were 1-4 μg L(-1) under the optimized conditions. Relative standard deviation (RSD%) for three replicates at three concentration levels of 6, 100 and 400 μg L(-1) were 5.9-8.0% while acceptable linear range with two orders of magnitude was obtained (R(2) = 0.99). The method was validated by the determination of the selected drugs in urine samples and the results indicated that this method has sufficient potential for enrichment and determination of the desired drugs in the urine sample. The relative recovery values were found to be in the range of 78-91%. Implementing the developed on-line μ-SPE method under the external magnetic field induction, led to higher extraction efficiencies for the selected drugs with various diamagnetic properties., (Copyright © 2016 Elsevier B.V. All rights reserved.)