Ferrocenemethanol
(FcMeOH,
97%), ferrocenecarboxylic acid (FcCOOH, 97%), potassium chloride (KCl,
99%), and chromium chloride hexahydrate (CrCl3·6H2O, 99%) were purchased from Sigma-Aldrich (Mississauga, ON).
Mediator solutions containing 0.9 mM FcMeOH with 0.1 M KCl were regularly
prepared in deionized water (18.2 MΩ cm). The FcMeOH solution
is diluted to half concentration with 1× phosphate-buffered saline
(PBS) when used experimentally. A FcCOOH stock solution of 0.5 mM
was prepared in PBS. At pH 7.4, FcCOOH dissociates into FcCOO– in solution. Stock solutions of 0.5 M CrCl3 were prepared in autoclaved deionized water and syringe filtered
through sterile 0.2 μm Supor Membranes (PALL Life Sciences,
Mississauga, ON). The compound 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium
bromide (MTT) was acquired from R&D Systems Inc. (Minneapolis,
MN) in the TACS MTT Cell Proliferation Assay Kit. Spectroscopic grade
dimethyl sulfoxide (DMSO) was used to dissolve the formazan crystals
(Caledon Laboratory Ltd., Georgetown, ON).
(FcMeOH,
97%), ferrocenecarboxylic acid (FcCOOH, 97%), potassium chloride (KCl,
99%), and chromium chloride hexahydrate (CrCl3·6H2O, 99%) were purchased from Sigma-Aldrich (Mississauga, ON).
Mediator solutions containing 0.9 mM FcMeOH with 0.1 M KCl were regularly
prepared in deionized water (18.2 MΩ cm). The FcMeOH solution
is diluted to half concentration with 1× phosphate-buffered saline
(PBS) when used experimentally. A FcCOOH stock solution of 0.5 mM
was prepared in PBS. At pH 7.4, FcCOOH dissociates into FcCOO– in solution. Stock solutions of 0.5 M CrCl3 were prepared in autoclaved deionized water and syringe filtered
through sterile 0.2 μm Supor Membranes (PALL Life Sciences,
Mississauga, ON). The compound 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium
bromide (MTT) was acquired from R&D Systems Inc. (Minneapolis,
MN) in the TACS MTT Cell Proliferation Assay Kit. Spectroscopic grade
dimethyl sulfoxide (DMSO) was used to dissolve the formazan crystals
(Caledon Laboratory Ltd., Georgetown, ON).