title: Ethanol as an alternative to formaldehyde for the enhancement of manganese(IV) chemiluminescence detection.
abstract: Previous applications of manganese(IV) as a chemiluminescence reagent have required the use of formaldehyde to enhance the emission intensity to analytically useful levels. However, this known human carcinogen (by inhalation) is not ideal for routine application. A wide range of alternative enhancers have been examined but to date none have been found to provide the dramatic increase in chemiluminescence intensities obtained using formaldehyde. Herein, we demonstrate that ethanol offers a simple, safe and inexpensive alternative to the use of formaldehyde for manganese(IV) chemiluminescence detection, without compromising signal intensity or sensitivity. For example, chemiluminescence signals for opiate alkaloids using 50-100% ethanol were 0.8-1.6-fold those using 2M formaldehyde. This innocuous alternative enhancer is shown to be a particularly effective for the direct detection of thiols and disulfides by manganese(IV) chemiluminescence, which we have applied to a simple HPLC procedure to determine a series of biomarkers of oxidative stress.
authors.affiliation: Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Faculty of Science, Engineering and Built Environment, Deakin University, Waurn Ponds, Victoria 3216, Australia.
authors.forename: Zoe M
authors.initials: ZM
authors.lastname: Smith
authors.affiliation: Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Faculty of Science, Engineering and Built Environment, Deakin University, Waurn Ponds, Victoria 3216, Australia.
authors.forename: Jessica M
authors.initials: JM
authors.lastname: Terry
authors.affiliation: Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Faculty of Science, Engineering and Built Environment, Deakin University, Waurn Ponds, Victoria 3216, Australia.
authors.forename: Neil W
authors.initials: NW
authors.lastname: Barnett
authors.affiliation: Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Faculty of Science, Engineering and Built Environment, Deakin University, Waurn Ponds, Victoria 3216, Australia. Electronic address: paul.francis@deakin.edu.au.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Francis
mesh_terms: D000470:Alkaloids / Q000032:analysis*; D000701:Analgesics, Opioid / Q000032:analysis*; D004220:Disulfides / Q000032:analysis*; D000431:Ethanol / Q000737:chemistry*; D017022:Flow Injection Analysis; D005557:Formaldehyde / Q000737:chemistry*; D006801:Humans; D008163:Luminescent Measurements / Q000379:methods*; D008345:Manganese / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000032:analysis*
chemical_list: D000470:Alkaloids; D000701:Analgesics, Opioid; D004220:Disulfides; D013438:Sulfhydryl Compounds; D005557:Formaldehyde; D000431:Ethanol; D008345:Manganese
keywords: Chemiluminescence; Disulfides; Flow injection analysis; High performance liquid chromatography; Manganese(IV); Thiols