Nanomaterial-based electrochemical biosensors for cytochrome c using cytochrome c reductase

作者：Pandiaraj Manickam; Madasamy Thangamuthu; Gollavilli Paradesi Naidu; Balamurugan Murugesan; Kotamraju Srigiridhar; Rao Vepa Kameswara; Bhargava Kalpana; Karunakaran Chandran^*

来源：Bioelectrochemistry, 2013, 91: 1-7.

DOI：10.1016/j.bioelechem.2012.09.004

• Cytochrome c reductase
• Cytochrome c quantification
• Apoptosis
• Gold nanoparticles
• Carbon nanotubes

Emerging evidences have pointed out that the release of cytochrome c (cyt c) from mitochondria into cytosol is a critical step in the activation of apoptosis. This article presents a novel approach for the detection of mitochondria cyt c release for the first time using cytochrome c reductase (CcR) immobilized on nanoparticles decorated electrodes. Two kinds of nanomaterial-based biosensor platforms were used: (a) carbon nanotubes (CNT) incorporated polypyrrole (PPy) matrix on Pt electrode and (b) self-assembled monolayer (SAM) functionalized gold nanoparticles (GNP) in PPy-Pt. Scanning electron microscope was used to characterize the surface morphologies of the nanomaterial modified electrodes. Cyclic voltammograms of both the biosensors showed reversible redox peaks at -0.45 and -034 V vs Ag/AgCl, characteristic of CcR In comparison, the CcR-CNT biosensor gave a detection limit of 0.5 +/- 0.03 mu M cyt c, which was 4-fold better than the CcR-GNP biosensor (2 +/- 0.03 mu M). Moreover, the CcR-CNT biosensor achieved a much larger linear range (1-1000 mu M) over the CcR-GNP biosensor (5-600 mu M) with 2-fold better sensitivity. The CcR-CNT-PPy-Pt biosensor was further applied to quantify the mitochondrial cyt c released in cytosol of A549 cells upon induction of apoptosis with doxorubicin, the results agreed well with standard western blot analysis.

• 出版日期2013-6