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A metabolic biofuel cell: conversion of human leukocyte metabolic activity to electrical currents.

Justin GA, Zhang Y, Cui XT, Bradberry CW, Sun M, Sclabassi RJ - J Biol Eng (2011)

Bottom Line: SCE for the PMA (phorbol ester) activated primary cells, with a notable absence of a reduction peak was observed.HPLC confirmed the release of serotonin (5-HT) from the PMA activated primary cells.It is believed that serotonin, among other biochemical species released by the activated cells, contributes to the observed BFC currents.

View Article: PubMed Central - HTML - PubMed

Affiliation: Computational Diagnostics, Inc, Pittsburgh, PA, USA. bobs@cdi.com.

ABSTRACT
An investigation of the electrochemical activity of human white blood cells (WBC) for biofuel cell (BFC) applications is described. WBCs isolated from whole human blood were suspended in PBS and introduced into the anode compartment of a proton exchange membrane (PEM) fuel cell. The cathode compartment contained a 50 mM potassium ferricyanide solution. Average current densities between 0.9 and 1.6 μA cm-2 and open circuit potentials (Voc) between 83 and 102 mV were obtained, which were both higher than control values. Cyclic voltammetry was used to investigate the electrochemical activity of the activated WBCs in an attempt to elucidate the mechanism of electron transfer between the cells and electrode. Voltammograms were obtained for the WBCs, including peripheral blood mononuclear cells (PBMCs - a lymphocyte-monocyte mixture isolated on a Ficoll gradient), a B lymphoblastoid cell line (BLCL), and two leukemia cell lines, namely K562 and Jurkat. An oxidation peak at about 363 mV vs. SCE for the PMA (phorbol ester) activated primary cells, with a notable absence of a reduction peak was observed. Oxidation peaks were not observed for the BLCL, K562 or Jurkat cell lines. HPLC confirmed the release of serotonin (5-HT) from the PMA activated primary cells. It is believed that serotonin, among other biochemical species released by the activated cells, contributes to the observed BFC currents.

No MeSH data available.


Related in: MedlinePlus

Variation in the amplitude of the oxidation peak current is plotted with PBMC density. Increasing the cell density is associated with an apparent non-linear increase in the oxidation peak.
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Figure 6: Variation in the amplitude of the oxidation peak current is plotted with PBMC density. Increasing the cell density is associated with an apparent non-linear increase in the oxidation peak.

Mentions: The 30 mV difference between the peak potentials reported in the literature (330 mV) and our own (360 mV) is not interpreted to be meaningful. 30 mV may not be significant, since scan conditions and electrode surface features can significantly impact peak potential. Figure 6 shows that the magnitude of the oxidation peak current increases with cell density, further verifying the relationship between the cells and the electrochemical activity. The relationship between cell density and peak current in Figure 6 appears to be nonlinear. However, this may only be an apparent nonlinearity as variability in how strongly cells from different subjects respond to the PMA activation agent can occur. As a consequence, this would affect how much serotonin is ultimately produced.


A metabolic biofuel cell: conversion of human leukocyte metabolic activity to electrical currents.

Justin GA, Zhang Y, Cui XT, Bradberry CW, Sun M, Sclabassi RJ - J Biol Eng (2011)

Variation in the amplitude of the oxidation peak current is plotted with PBMC density. Increasing the cell density is associated with an apparent non-linear increase in the oxidation peak.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3113927&req=5

Figure 6: Variation in the amplitude of the oxidation peak current is plotted with PBMC density. Increasing the cell density is associated with an apparent non-linear increase in the oxidation peak.
Mentions: The 30 mV difference between the peak potentials reported in the literature (330 mV) and our own (360 mV) is not interpreted to be meaningful. 30 mV may not be significant, since scan conditions and electrode surface features can significantly impact peak potential. Figure 6 shows that the magnitude of the oxidation peak current increases with cell density, further verifying the relationship between the cells and the electrochemical activity. The relationship between cell density and peak current in Figure 6 appears to be nonlinear. However, this may only be an apparent nonlinearity as variability in how strongly cells from different subjects respond to the PMA activation agent can occur. As a consequence, this would affect how much serotonin is ultimately produced.

Bottom Line: SCE for the PMA (phorbol ester) activated primary cells, with a notable absence of a reduction peak was observed.HPLC confirmed the release of serotonin (5-HT) from the PMA activated primary cells.It is believed that serotonin, among other biochemical species released by the activated cells, contributes to the observed BFC currents.

View Article: PubMed Central - HTML - PubMed

Affiliation: Computational Diagnostics, Inc, Pittsburgh, PA, USA. bobs@cdi.com.

ABSTRACT
An investigation of the electrochemical activity of human white blood cells (WBC) for biofuel cell (BFC) applications is described. WBCs isolated from whole human blood were suspended in PBS and introduced into the anode compartment of a proton exchange membrane (PEM) fuel cell. The cathode compartment contained a 50 mM potassium ferricyanide solution. Average current densities between 0.9 and 1.6 μA cm-2 and open circuit potentials (Voc) between 83 and 102 mV were obtained, which were both higher than control values. Cyclic voltammetry was used to investigate the electrochemical activity of the activated WBCs in an attempt to elucidate the mechanism of electron transfer between the cells and electrode. Voltammograms were obtained for the WBCs, including peripheral blood mononuclear cells (PBMCs - a lymphocyte-monocyte mixture isolated on a Ficoll gradient), a B lymphoblastoid cell line (BLCL), and two leukemia cell lines, namely K562 and Jurkat. An oxidation peak at about 363 mV vs. SCE for the PMA (phorbol ester) activated primary cells, with a notable absence of a reduction peak was observed. Oxidation peaks were not observed for the BLCL, K562 or Jurkat cell lines. HPLC confirmed the release of serotonin (5-HT) from the PMA activated primary cells. It is believed that serotonin, among other biochemical species released by the activated cells, contributes to the observed BFC currents.

No MeSH data available.


Related in: MedlinePlus