Spectrofluorometric determination of DNA and RNA with berberine

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