Determination of nucleic acids using fluorescence probe sensitized by microemulsion.
Because the fluorescence of azur A can be quenched by adding nucleic acid, a sensitive fluorometric method for determination of nucleic acids at nanogram levels was established. Using optimal conditions, the calibration curves were linear in the range of 0-6.0 microg/mL for calf thymus deoxyribonucleic acid (ct DNA) and 0-7.0 microg/mL for herring sperm DNA (hs DNA). The limits of determination were 3.5 and 3.8 ng/mL, respectively, which shows the high sensitivity of this method. Triton X-100 microemulsion was applied as a sensitive media to enhance the sensitivity. The binding mode concerning the interactions of azur A with nucleic acids was also studied and the association constant with different binding numbers was obtained. The method has been applied to the determination of nucleic acid in both synthetic and real samples, such as cauliflower and pork liver, with satisfactory results.
Wei
Qin
Q
Jinan University, School of Chemistry and Chemical Engineering, Jinan 250022, People's Republic of China. sdjndxwq@263.net
Zhang
Hui
H
Du
Bin
B
Duan
Caihong
C
D000465:Algorithms; D000818:Animals; D001399:Azure Stains / Q000737:chemistry; D001937:Brassica / Q000737:chemistry; D004247:DNA / Q000032:analysis; D004655:Emulsions; D005456:Fluorescent Dyes; D006863:Hydrogen-Ion Concentration; D008099:Liver / Q000737:chemistry; D009691:Nucleic Acid Denaturation; D009696:Nucleic Acids / Q000032:analysis*; D017830:Octoxynol; D012015:Reference Standards; D012996:Solutions; D013050:Spectrometry, Fluorescence; D013501:Surface-Active Agents; D013552:Swine
D001399:Azure Stains; D004655:Emulsions; D005456:Fluorescent Dyes; D009696:Nucleic Acids; D012996:Solutions; D013501:Surface-Active Agents; D017830:Octoxynol; D004247:DNA; C025818:Azure A