Abstract
The present study focused on the synthesis and application of novel isocyanate-modified carrageenan polymers as sorbent materials for pre-concentration and removal of diclofenac (DCF) and carbamazepine (CBZ) in different aqueous matrices (surface waters and wastewaters). The polymer materials were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermal Gravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM). The effects on the adsorption behavior were studied, and the equilibrium data were fitted by the Langmuir and Freundlich models. The maximum adsorption capacity (Qmax) was determined by Langmuir–Freundlich model and was ranged for iota-carrageenan (iCAR) from 7.44 to 8.51 mg/g for CBZ and 23.41 to 35.78 mg/g for DCF and for kappa-carrageenan (kCAR) from 7.07 to 13.78 mg/g for CBZ and 22.66 to 49.29 mg/g for DCF. In the next step, dispersive solid phase extraction (D-SPE) methodology followed by liquid desorption and liquid chromatography mass spectrometry (LC/MS) has been developed and validated. The factors, which affect the performance of D-SPE, were investigated. Then, the optimization of extraction time, sorbent mass and eluent’s volume was carried out using a central composite design (CCD) and response surface methodology (RSM). Under the optimized conditions, good linear relationships have been achieved with the correlation coefficient (R2) varying from 0.9901 to 0.995. The limits of detections (LODs) and limits of quantifications (LOQs) ranged 0.042–0.090 μg/L and 0.137–0.298 μg/L, respectively. The results of the recoveries were 70–108% for both analytes, while the precisions were 2.8–17.5% were obtained, which indicated that the method was suitable for the analysis of both compounds in aqueous matrices.
Highlights
Detection of pharmaceutically active compounds in the aquatic environment has raised concerns over their potential adverse effects on the environment [1,2,3]
The morphology of the prepared materials was examined by Scanning Electron Microscopy (SEM) images
tolylene diisocyanate (TDI) caused more rigid and hard surface (Figure 1c,d), while after chopping in cutting mill, the particles retained an irregular shape with sharp edges
Summary
Detection of pharmaceutically active compounds in the aquatic environment has raised concerns over their potential adverse effects on the environment [1,2,3]. Carbamazepine (CBZ), a well-known antiepileptic compound, and diclofenac (DCF), a common non-steroidal anti-inflammatory drug, owing to ever-increasing consumption, inappropriate disposal and their incomplete removal in wastewater treatment plants (WWTPs) have been found ubiquitously in wastewater effluents [4,5,6] and Polymers 2017, 9, 595; doi:10.3390/polym9110595 www.mdpi.com/journal/polymers. The anti-inflammatory DCF was identified for priority investigation because of risk perception and has recently been included on the “watch list” of priority substances under the Water Framework Directive [10]. The global consumption of DCF is estimated to be 940 tons per year, with a defined daily dose of 100 mg [9,11]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
