One-step synthesis of porphyrinic iron-based metal-organic framework/ordered mesoporous carbon for electrochemical detection of hydrogen peroxide in living cells

A novel porphyrinic iron metal-organic framework (pFeMOF)-decorated ordered mesoporous carbon (OMC) was developed to detect hydrogen peroxide (H2O2) released from viable cells. The pFeMOF/OMC hybrid materials were synthesized via a simple one-step hydrothermal method. Fe (III) ion could coordinate with carboxylates of porphyrin groups strongly, leading to more stable MOFs. Because of the mimic peroxidase property of pFeMOF, amplified electrochemical signal could be obtained. The carbon skeleton of OMC revealed a function of restriction for the growth of pFeMOF crystallites, resulting in more active sites to reduce H2O2. The increased amount of mesopores brings faster diffusion. Moreover, the electrical conductivity and stability has been improved due to the introduction of OMC. The electrocatalytic reduction of H2O2 displayed two segments linearity range from 0.5 to 70.5 M and 70.5 to 1830.5 mu M, with high sensitivity of 67.54 mu A mM(-1) in the range of low concentration and 22.29 mu A mM(-1) of high concentration as well as a low limit of detection (LOD) as 0.45 mu M. In addition, the pFeMOF/OMC/glassy carbon electrode (GCE) exhibited outstanding property to resist interference, long-term stability and repeatability. Due to these excellent analytical performances, the as-prepared biosensor was applied to detect H2O2 released from living cells with satisfactory outcome. These results display that this new nanocomposite has the potential to fabricate electrochemical sensing platform for nonenzymatic biosensing. (C) 2017 Elsevier B.V. All rights reserved.