Molecularly Imprinted Polymers Combined with Electrochemical Sensors for Food Contaminants Analysis

Detection of relevant contaminants using screening approaches is a key issue to ensure food safety and respect for the regulatory limits established. Electrochemical sensors present several advantages such as rapidity; ease of use; possibility of on-site analysis and low cost. The lack of selectivity for electrochemical sensors working in complex samples as food may be overcome by coupling them with molecularly imprinted polymers (MIPs). MIPs are synthetic materials that mimic biological receptors and are produced by the polymerization of functional monomers in presence of a target analyte. This paper critically reviews and discusses the recent progress in MIP-based electrochemical sensors for food safety. A brief introduction on MIPs and electrochemical sensors is given; followed by a discussion of the recent achievements for various MIPs-based electrochemical sensors for food contaminants analysis. Both electropolymerization and chemical synthesis of MIP-based electrochemical sensing are discussed as well as the relevant applications of MIPs used in sample preparation and then coupled to electrochemical analysis. Future perspectives and challenges have been eventually given.     

Ferroxidase Activity in Eukaryotic Ferritin is Controlled by Accessory‐Iron‐Binding Sites in the Catalytic Cavity

Ferritins are iron‐storage nanocage proteins that catalyze the oxidation of Fe²⁺ to Fe³⁺ at ferroxidase sites. By a combination of structural and spectroscopic techniques, Asp140, together with previously identified Glu57 and Glu136, is demonstrated to be an essential residue to promote the iron oxidation at the ferroxidase site. However, the presence of these three carboxylate moieties in close proximity to the catalytic centers is not essential to achieve binding of the Fe²⁺ substrate to the diferric ferroxidase sites with the same coordination geometries as in the wild‐type cages.     

Electrochemical alcohol oxidation: a comparative study of the behavior of methanol,ethanol, propanol,and butanol on carbon-supported PtSn,PtCu, and Pt nanoparticles

Journal of Solid State Electrochemistry - Carbon-supported PtCu and PtSn (both with an atomic ratio of 3:1) nanoparticles were prepared by reducing Pt, Sn, and Cu precursors via refluxing in...     

Palladium-platinum electrocatalysts for the ethanol oxidation reaction: comparison of electrochemical activities in acid and alkaline media

Journal of Solid State Electrochemistry - Carbon-supported Pd, Pt, Pt1Pd1, and Pt3Pd1 electrocatalysts were prepared by metal ion chemical reduction with borohydride. The electrocatalysts were...     

Biological and Catalytic Applications of Pd(II)-Indenyl Complexes Bearing Phosphine and N-Heterocyclic Carbene Ligands

A general synthetic entryway into novel cationic Pd(II) indenyl complexes bearing one alkyl/aryl phosphine and one N-heterocyclic carbene is reported. All metal complexes have been exhaustively characterized by spectroscopic and structural analyses, highlighting that the indenyl fragment has an hapticity intermediate between η³ and η⁵. Most of the target complexes are stable in solid state and in solution for a long time. Two different applications of these organopalladium compounds are proposed. Firstly, they have been tested as antiproliferative agents towards three different ovarian cancer cell lines, showing a cytotoxicity significantly higher than that of cisplatin, with a clear dependence on the nature of the coordinated phosphine. Moreover, the similar cytotoxicity towards cisplatin-sensitive and cisplatin-resistant cell lines suggests that these new palladium derivatives act with a different mechanism of action with respect to classical platinum-based drugs. Finally, the water-soluble palladium complexes bearing 1,3,5-triaza-7-phosphaadamantane (PTA) have demonstrated interesting catalytic performances in Suzuki–Miyaura coupling in aqueous media, being, inter alia, readily and efficiently recyclable.