{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:23:46Z","timestamp":1760145826037,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2024,8,25]],"date-time":"2024-08-25T00:00:00Z","timestamp":1724544000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Medical University Lodz","award":["503\/1-079-01\/503-11-001"],"award-info":[{"award-number":["503\/1-079-01\/503-11-001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>A Fe2+-EGTA(ethylene glycol-bis (\u03b2-aminoethyl ether)-N,N,N\u2032,N\u2032-tetraacetic acid)-H2O2 system emits photons, and quenching this chemiluminescence can be used for determination of anti-hydroxyl radical (\u2022OH) activity of various compounds. The generation of \u2022OH and light emission due to oxidative damage to EGTA may depend on the buffer and pH of the reaction milieu. In this study, we evaluated the effect of pH from 6.0 to 7.4 (that may occur in human cells) stabilized with 10 mM phosphate buffer (main intracellular buffer) on a chemiluminescence signal and the ratio of this signal to noise (light emission from medium alone). The highest signal (4698 \u00b1 583 RLU) and signal-to-noise ratio (9.7 \u00b1 1.5) were noted for pH 6.6. Lower and higher pH caused suppression of these variables to 2696 \u00b1 292 RLU, 4.0 \u00b1 0.8 at pH 6.2 and to 3946 \u00b1 558 RLU, 5.0 \u00b1 1.5 at pH 7.4, respectively. The following processes may explain these observations: enhancement and inhibition of \u2022OH production in lower and higher pH; formation of insoluble Fe(OH)3 at neutral and alkaline environments; augmentation of \u2022OH production by phosphates at weakly acidic and neutral environments; and decreased regeneration of Fe2+-EGTA in an acidic environment. Fe2+-EGTA-H2O2 system in 10 mM phosphate buffer pH 6.6 seems optimal for the determination of anti-\u2022OH activity.<\/jats:p>","DOI":"10.3390\/molecules29174014","type":"journal-article","created":{"date-parts":[[2024,8,26]],"date-time":"2024-08-26T03:14:31Z","timestamp":1724642071000},"page":"4014","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Light Emission from Fe2+-EGTA-H2O2 System Depends on the pH of the Reaction Milieu within the Range That May Occur in Cells of the Human Body"],"prefix":"10.3390","volume":"29","author":[{"given":"Krzysztof","family":"Sasak","sequence":"first","affiliation":[{"name":"Department of Medical Imaging Techniques, Medical University of Lodz, Lindleya 6, 90-131 Lodz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michal","family":"Nowak","sequence":"additional","affiliation":[{"name":"Radiation Protection, University Hospital No. 2, Medical University of Lodz, Zeromskiego 113, 90-549 Lodz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anna","family":"Wlodarczyk","sequence":"additional","affiliation":[{"name":"Department of Sleep Medicine and Metabolic Disorders, Medical University of Lodz, Mazowiecka 6\/8, 92-215 Lodz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Agata","family":"Sarniak","sequence":"additional","affiliation":[{"name":"Department of Clinical Physiology, Medical University of Lodz, Mazowiecka 6\/8, 92-215 Lodz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wieslaw","family":"Tryniszewski","sequence":"additional","affiliation":[{"name":"Department of Radiological and Isotopic Diagnostics and Therapy, Medical University of Lodz, Zeromskiego 113, 90-549 Lodz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3445-6930","authenticated-orcid":false,"given":"Dariusz","family":"Nowak","sequence":"additional","affiliation":[{"name":"Department of Clinical Physiology, Medical University of Lodz, Mazowiecka 6\/8, 92-215 Lodz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1865","DOI":"10.1016\/S0024-3205(99)00439-7","article-title":"Chemistry, physiology and pathology of free radicals","volume":"65","author":"Bergendi","year":"1999","journal-title":"Life Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"194","DOI":"10.1016\/j.saa.2018.01.026","article-title":"Structural andimmunological characterisation of hydroxyl radical modified human IgG: Clinicalcorrelation in rheumatoid arthritis","volume":"194","author":"Islam","year":"2018","journal-title":"Spectrochim. 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