NMR Characterization of Polymers Formed in Diazotizing Mixtures of Luminol and 3-Amino-L-Tyrosine
Abstract
A melanin-like polymer was prepared by diazotizing luminol (5-amino- 2,3-dihydro-1, 4-phthalazinedione) and 3-amino-L-tyrosine in a mixed water/ dimethylsulfoxide solvent; this was followed by acetone precipitation and aging of the solid residue for a month (the polymer forms slowly in the solid residue) . An aqueous solution containing 0.50 F NaOH, 0.0011 M luminol, 0.010 F potassium formate and the polymer at a concentration of 0.050 mg/mL was observed to undergo an instantaneous seven-fold increase of chemiluminescence when the solution was subjected to a 0.5 Watt/mL irradiation with 20 kHz acoustic energy. This sonochemiluminescent property suggests that earlier reports of strobes of luminescense induced by pulsed microwave irradiations of aqueous solutions of the polymer might have an origin in the microwave acoustic effect. Since the sonochemiluminescent effect is marked and easily detected, the polymer may be applicable as a dosimeter for studying acoustic effects in pulsed, high-powered microwave irradiations, especially where the target geometry is complex. Further insight into the observed properties will depend on a characterization of the structure of the polymer, which is currently not known. Attempts at a structural characterization have been hampered thus far by a lack of suitable polymer fragments, i.e., a reliable means for fragmenting the polymer or limiting its DPn has not been found.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 24, 1993
- Accession Number
- ADA266093
Entities
People
- John R. Wright