Magnetic ZnFe2O4@polyhydroxybenzoic acid nanostructure for efficient B.subtilis capturing

This work focuses on preparing an efficient bacterial capture system based on the magnetic polyphenolic nanostructure. For a reason, a one-step hydrothermally route was employed to prepare ZnFe2O4@hydroxybenzoic acid - resorcinol nanohybrid. The nanostructure was characterized by X–ray diffraction (XRD), field emission scanning electron microscopy (FE–SEM), transmission electron microscopy (TEM) vibration sample magnetometry (VSM) and zeta potential measurement. Bacillus subtilis was employed as a sample pathogen to evaluate bacterial capture efficiency of the nanohybrid. Characterization results confirmed that the hybrid material is in nano scale. Moreover, it has a magnetic saturation of 6.7 emu g-1 which is in right level to be employed for magnetic separation. Effect of relevant variables on capturing efficiency including pH, contact time and adsorbent dosage was investigated, and optimum levels were obtained. It found that the capturing efficiency is independent of solution pH. Moreover, capturing experiments showed fast equilibrium time of 20 min with the effectiveness more than 99%.