Electron transfer reactivity and the catalytic activity of horseradish peroxidase incorporated in dipalmitoylphosphatidic acid films

Direct electrochemistry and electrocatalysis of horseradish peroxidase with hyaluronic acid–ionic liquid–cadmium sulfide nanorod composite material

“…Among them the protein film modified electrodes have been widely studied because the presence of biocompatible film on the electrode surface can provide suitable microenvironments to keep the native structure of protein and accelerate the direct electron transfer rate between protein and electrodes [5,6]. Many composite films including biopolymers, sol-gel, nanomaterials and polyelectrolytes have been used in the film fabrication [7][8][9][10][11][12][13][14]. In recent years ionic liquids (ILs) have also been used for the fabrication of new kind of composite film.…”

Carbon felt-based bioelectrocatalytic flow-through detectors: Highly sensitive amperometric determination of H2O2 based on a direct electrochemistry of covalently modified horseradish peroxidase using cyanuric chloride as a linking agent

“…Large ratio of the CF surface and solution volume in the electrochemical cell (in the present case; 4.95 cm 2 /0.9 cm 3 ) may permits high current efficiency and high sensitivity. After the background current of the detector had reached steady-state values at 0 V vs. Ag/AgCl, standard H 2 O 2 sample solutions were injected, and the cathodic peak current responses based on the HRP-catalyzed electro-reduction The HRP-ccCF showed well-defined redox couple at about −0.23 V vs. Ag/AgCl attributed to HRP-heme Fe III /Fe II redox couple [22,29], while cc-CF showed no apparent voltammetric peak under the same conditions. Fig.…”

“…Although a number of HRP-modified electrodes showed DETbased heme Fe III /Fe II couple [20][21][22][23][24][25][26][27][28][29][30], most of these electrodes employ various films (e.g., anionic exchange regin [20]; cationic surfactant film [21]; DNA film [22]; conducting polymer [23]; anionic ionomer film [24]; protein/hyaluronic acid layer-by-layer film [26]; anionic lipid film [29]; amphiphilic hydrogel film [30]), to modify HRP on the electrode surface to facilitate the DET between HRP and electrodes. Furthermore, the topic has been focused on the DET mechanism [20,21,24,30], not on H 2 O 2 -sensing.…”

Electron transfer and interfacial behavior of redox proteins

“…Therefore, direct electrochemistry of Hb [50], HRP [51] and Cyt c [52] has been observed at PC/protein co-modified PGE. Dipalmitoylphosphatidic acid (DPPA) has been used to entrap Hb [53] and HRP [54] onto PGE, and the corresponding DET of the proteins has been achieved. This entrapment is because phosphatidic acids are the hydration products of phospholipids belonging to anionic-type lipids and are able to form bilayer-like arrangement, and may have some similar functional properties as phospholipids.…”

“…Nevertheless, most heme proteins are reported to electrocatalyze the reduction of H 2 O 2 under a much lower potential after being entrapped in films. The mechanism of the reaction is interpreted as follows [54,102]: …”