Selective and rapid extraction of piroxicam from water and plasma samples using magnetic imprinted polymeric nanosorbent: Synthesis, characterization and application

Here, a selective nano-sized magnetic sorbent based on iron oxide (Fe3O4) core and molecular imprinted polymer (MIP) shell was synthesized and used as a selective sorbent for separation of piroxicam (PIX) from aqueous media. The magnetic MIP functionalized with -NH2 group (Fe3O4@SiO2@NH2) was prepared by a surface imprinting approach. The characterization of the MMIP sorbent was carried out by scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), Brumauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) analyses. The results indicated that the magnetic sorbent were as microspherical nanoparticles with the average size of 50 nm, with well water-dispersibility and easily magnetically separation. The influence of the variables on PIX recovery including initial pH of sample solution, volume and concentration of the eluent, ultrasonic time, ionic strength, and the amount of MMIP were studied and optimized. The linear range (LR), relative standard deviation (RSD) and limit of detection (LOD = 3S(b)/m) for determination of PIX were found to be 0.01-10.0 mg L-1, 2.56 % and 5.0 ng mL(-1), respectively. The used Fe3O4@SiO2@NH2-MMIP sorbent can be regenerated with 2 ml of pure methanol, without any significant decrease in its adsorption affinity. The results demonstrated an enhanced affinity for the as-prepared MMIP toward the PIX compared to non-imprinted polymer.