magnetic solid-phase extraction based on ni-zn ferrite/ mg–fe (cl) layered double hydroxide magnetite nanocomposite for determination of folic acid in real samples by differential pulse voltammetry

In the present study, magnetic solid-phase extraction (mspe) method in combination with differential pulse voltammetry (dpv) electrochemical detection was applied to determine folic acid. mspe method using a ni-zn ferrite/mg–fe (cl) layered double hydroxide (ldh)- based magnetite nanocomposite was developed for the preconcentration of folic acid in aqueous solutions. the electrochemical technique was applied by using a glassy carbon electrode modified with carbon nanotubes (cnts) for determination of folic acid. the synthesized mg–fe (cl) ldh/ni-zn-fe2o4 nanocomposite was characterized via x-ray diffraction, scanning electron microscopy and edx. for achieving the best conditions of the extraction process, various parameters affecting the extraction recovery such as solution ph, the amount of mg–fe (cl) ldh/ni-zn-fe2o4 nanocomposie, extraction time, elution conditions, sample volume and interfering effect of ions were studied. under the optimized experimental conditions, linear range of calibration graph after preconcentration was obtained in the ranges of 0.1-8 µm with correlation coefficient of 0.9958 and detection limit of 5.6 ×10-8 m. to evaluate the precision of the method, 5 replicate samples at the certain concentration level were analyzed and the relative standard deviation value of 0.835 was reported. also, to study the accuracy of the method, the analysis of folic acid-spiked samples was performed and the satisfactory recovery value was obtained.