These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Detection of free radicals generated from hydrogen peroxide, gallic acid and haemoprotein chemiluminescence system by electron spin resonance spectroscopy.
    Author: Kawane M, Iida T, Yoshiki Y, Okubo K, Tsunakawa M.
    Journal: Luminescence; 1999; 14(6):321-5. PubMed ID: 10602301.
    Abstract:
    Low-level chemiluminescence is produced in a hydrogen peroxide (H(2)O(2))/gallic acid/haemoprotein system with single broad peaks around 520 nm, regardless of the biological role of the haemoprotein. The free haem iron systems (haemin and haematin systems) gave a higher photon intensity (1.5 x 10(4) and 2.0 x 10(4) cps) than that of the H(2)O(2)/gallic acid/haematoporphyrin system. These results indicated that haem iron plays a significant role in the photon emission of haemoprotein systems. A free radical with a g value of 2. 0058 was detected through a direct electron spin resonance (ESR) method. The photon intensity of the H(2)O(2)/gallic acid/haemoprotein system decreased in the order: HRP > cytochrome c > myoglobin > haemoglobin, and this corresponded to the decrease in radical intensity. These results indicated that the formation of the free radical with a g value of 2.0058 may be the key step for chemiluminescence in the H(2)O(2)/gallic acid/haemoprotein system. A quartet line similar to DMPO-OH adducts and uncomplexed free radicals (g = 2.0058) was detected using the ESR spin-trapping method in the H(2)O(2)/gallic acid/cytochrome c system.
    [Abstract] [Full Text] [Related] [New Search]