Spectrofluorometric determination of DNA and RNA with berberine

On binding to nucleic acids, the dye berberine increases its fluorescence q uantum efficiency by a factor of 25-30. Based on this, an easy, rapid and a ccurate method for the determination of nucleic acids was developed. Berber ine is very like ethidium bromide (EB), but it is non-poisonous. Determinat ion can be made at any pH between 4 and 10, where the native structure of D NA and RNA is not disrupted. The maximum emission is near 520 nm for excita tion at 355 or 450 nm. This method has good sensitivity (0.01 mu g ml(-1) o f ctDNA), high selectivity and a wide linear range (0.05-14.0 mu g ml(-1) o f ctDNA). (C) 1999 Elsevier Science B.V. All rights reserved.