| This paper established SPE-HPLC detection method in trace pharmaceutical and personnal care products (PPCPs) including Carbamazepine, Ibuprofen, Amlodipine and Atenolol in aquatic environment and discussed the separation effect of PPCPs with charged membrane synthesized by polyethersulfone (PES) ultraflitration membrane as the support layer and 2-hydroxypropyl trimethyl ammonium chloride chitosan (HTCC) as the active layer. It also evaluated the RSD of intra-day and intre-day assays, the limit of detection (LOD) and the recovery rate of PPCPs in SPE-HPLC detection method and optimized the condition of SPE. The structural characterization of HTCC/PES membrane was studied by scanning electron microscopy (SEM) and atomic force microscope (AFM). The pure water flux, mechanical properties and swelling degree of the composite membrane were also tested. Finally, this paper discussed the separation effects of Atenolol, Amlodipine, Ibuprofen and Carbamazepine under factors including HTCC with different degree of substitution (DS), the charge of PPCPs. ionic strength and feed water pH for HTCC/PES positively charged membrane.This paper adopted C18 Reversed Phase Column as separation and enrichment of PPCPs and used Methanol (or added potassium dihydrogen phosphate) as mobile phase to separate and detect the concentration of PPCPs by liquid chromatography. The results showed that LODs of Carbamazepine. Ibuprofen, Amlodipine and Atenolol were 0.25 μg/L,10 μg/L,0.25 μg/L,2.5 μg/L, respectively. The RSD of intra-day (n=5) assays were 1.4,0.7,1.7,1.2%, respectively. The RSD of inter-day (n=5) assays were 5.6,3.9,4.4,4.3%, respectively. The recovery rate of Carbamazepine, Ibuprofen, Amlodipine and Atenolol were in the range of 89 ～98,87～98,90～99 and 92～98%, respectively. Thus it can be seen that the RSD of intra-day (RSD<5%, n=5) and inter-day (RSD<10%, n=5) assays were reliable and accurate. Both of them can satisfy the requirement of quantitative analysis (RSD≤20%). In conclusion, SPE-HPLE method can be well applied to detect the trace PPCPs in aquatic environment.HTCC/PES positively charged NF membrane was basically a compound of HTCC (DS= 87.6%) as surface active layer and PES ultrafiltration membrane as its supporting layer. The whole cross-linking reaction lasted for 22 hours, using 1.0 wt% HTCC casting solution and 1.9 wt% ECH as crosslinker. The pure water flux of the composite membrane was 11.6 L/m2-h. The mechanical strength was 234.53 MPa and the elongation at break was 20.75%. The swelling degree was 80.51% and the RMS was 29.2 nm. In conditions of normal temperature,0.6 MPa operating pressure and feed water pH=7, the rejection of trace Carbamazepine, Ibuprofen, Amlodipine and Atenolol in aquatic environment with HTCC/PES membrane were 75.4,77.0,88.7,86.7% respectively. And it showed that the role of interception to positively charged Amlodipine (pKa=8.6) and Atenolol (pKa=9.43) by HTCC/PES positively charged membrane mainly depended on the electrostatic repulsion and Ca2+ carried stronger weakening effects of the electric double layer formed on HTCC/PES membrane’s surface than Na+. In addition, it was also found that the tendency of interception of Amlodipine and Atenolol with HTCC/PES positively charged NF membrane was similarly affected by ionic strength and the pH of feed water, but the influence of neutral Carbamazepine (pKa=7) was quite limited. The efficiency of rejection of Ibuprofen (pKa= 4.47) was increased progressively with the increase of the concentration of the ion. When the pH of water was 7, Ibuprofen had a higher rejection ration with HTCC/PES positively charged NF membrane, compared to alkaline or neutral condition of water. |
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