Fluorescence studies on the reduction of quinone by cyanide in aqueous 2-hydroxypropyl-β-cyclodextrin solutions

✍ Scribed by C.A. Groom; J.H.T. Luong

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 667 KB
• Volume: 296
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(94)80244-0

✦ Synopsis

Water-soluble 2-hydroxypropyl-&

was used to enclose l,Cdibenxoquinone, 1,4-naphthoquinone, and 9,10anthraquinone to form inclusion complexes. The inclusion complex of 1,4dibenxoquinone was the most reactive of the three complexes in the presence of cyanide anion. The 1,4_dibenxoquinone inclusion complex reacted with cyanide anion to form a fluorescent product with stable excitation and emission maxima at 410 and 480 mn, respectively. Assuming one to one stoichiometry the formation constant for 2-hydroxypropyl-&zyclodextrin and 1,4dibenxoquinone was estimated to be 4 M-l. Formation of the inclusion complex did not enhance fluorescence yield but increased the rate of product formation in aqueous solutions. In the presence of excess cyanide the limit of detection for 1,6dibenxoquinone was 0.006 mM with a linear range of 0.01 to 0.04 mM. For cyanide detection the linear range of the assay was 2 to 10 mM with a detection limit of 0.041 mM. Rate assays for cyanide possessed linear ranges from 0.041 to 12 mM. The reaction was used to detect cyanide in beverages, acetaminophen preparations and brass plating solutions.