Electrochemical generation of ferrylmyoglobin during oxidation of styrene with films of DNA and a poly (ester sulfonic acid) ionomer.
The chemistry of electrochemically-driven myoglobin-catalyzed oxidation of styrene was investigated in films of DNA or Eastman AQ ionomer on optically transparent electrodes. Conversion of styrene to styrene oxide proceeded via a ferrylmyoglobin radical intermediate. Ferrylmyoglobins were clearly detected by spectroelectrochemistry in films of 1-4 mm thick. The ferrylmyoglobin radical is produced by reaction of metmyoglobin (Mb) in the films with hydrogen peroxide formed by electrochemical catalytic reduction of oxygen catalyzed by Mb. Thus, electrochemically-driven styrene oxidation with these films proceeds by a 'doubly catalytic' electrode-driven reduction-oxidation pathway. Ferrylmyoglobin formation during electrolysis of Mb-DNA films in aerobic solutions was much faster, and styrene oxidation occurred with less Mb decomposition compared to the Mb-AQ films. The better performance of Mb-DNA films is correlated with a larger fraction of electroactive Mb and better stability than for the Mb-AQ films.
Kong
J
J
Department of Chemistry, Fudan University, Shanghai, China. jkong@fudan.ac.cn
Mbindyo
J N
JN
Wu
X
X
Zhou
J X
JX
Rusling
J F
JF
D000818:Animals; D002417:Cattle; D004247:DNA / Q000737:chemistry* / Q000378:metabolism*; D004563:Electrochemistry; D006736:Horses; D066298:In Vitro Techniques; D008786:Metmyoglobin / Q000737:chemistry* / Q000378:metabolism*; D010084:Oxidation-Reduction; D011091:Polyesters / Q000737:chemistry / Q000378:metabolism; D013053:Spectrophotometry; D020058:Styrene / Q000737:chemistry* / Q000378:metabolism*
D011091:Polyesters; C028048:ferrylmyoglobin; D008786:Metmyoglobin; D020058:Styrene; D004247:DNA