Novel adsorbents, magnetite nanoparticles modified with pectin shell and silica/pectin double shell, were fabricated and tested for single dye and dye mixture adsorption from water samples. Cationic dyes methylene blue (MB) and crystal violet (CV) and anionic dyes methyl orange (MO) and Eriochrome black T (EBT) were employed to assess dye removal efficiency. The influence of pH, amount of adsorbent, initial dye concentration and contact time was investigated. Results indicated that the optimum pH for removing cationic dyes was 8.0 and 2.0 for anionic dyes. The kinetic studies showed rapid sorption dynamics following a second-order kinetic model. Dye adsorption equilibrium data were fitted well to the Sips isotherm for cationic and anionic dyes. The maximum monolayer capacity, (q_max) for MB, CV, EBT and MO was calculated from Sips as 197.18, 180.29, 65.35 and 26.75 mg g⁻¹ respectively for magnetite/silica/pectin NPs and 168.72, 140.49, 72.35 and 27.22 mg g⁻¹ respectively for magnetite/pectin nanoparticles. For dye mixture adsorption, a new HPLC assay was proposed for quantitation of dyes in treated samples. The results came in accordance with that of single dye adsorption where the magnetite/pectin NPs showed preferred adsorption to anionic dyes while the magnetite/silica/pectin NPs had more affinity to cationic dyes. Thus, our proposed NPs can be used as cheap and efficient adsorbents for removal of cationic and anionic dyes from aqueous solutions.

Cyclocreatine and its water-soluble derivative, cyclocreatine phosphate (CCrP), are potent cardioprotective drugs. Based on recent animal studies, CCrP, FDA-awarded Orphan Drug Designation, has a promising role in increasing the success rate of patients undergoing heart transplantation surgery by preserving donor hearts during transportation and improving the recovery of transplanted hearts in recipient patients. In addition, CCrP is under investigation as a promising treatment for creatine transporter deficiency, an X-linked inborn error resulting in a poor quality of life for both the patients and the caregiver. A newly designed molecularly imprinted polymer (MIP) material was fabricated by the anodic electropolymerization of o-phenylenediamine on screen-printed carbon electrodes and was successfully applied as an impedimetric sensor for CCrP determination to dramatically reduce the analysis time during both the clinical trial phases and drug development process. To enhance the overall performance of the proposed sensor, studies were performed to optimize the electropolymerization conditions, incubation time, and pH of the background electrolyte. Scanning electron microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry were used to characterize the behavior of the developed ultrathin MIP membrane. The CCrP-imprinted polymer has a high recognition affinity for the template molecule because of the formation of 3D complementary cavities within the polymer. The developed MIP impedimetric sensor had good linearity, repeatability, reproducibility, and stability within the linear concentration range of 1 × 10^–9 to 1 × 10^–7 mol/L, with a low limit of detection down to 2.47 × 10^–10 mol/L. To verify the applicability of the proposed sensor, it was used to quantify CCrP in spiked plasma samples.

A novel molecularly imprinted polymer on Fe₃O₄nanoparticles was applied to extract antiepileptic drug; levetiracetam from plasma for TDM purposes.