吡啰红Y共振光散射法测定纳克级核酸

研究了二苯并吡喃类染料吡口罗红Y(PY)与核酸作用的共振光散射光谱,在pH11.5～12.0Tris-NaOH缓冲溶液中,1.75×10-5mol/L的PY溶液加入核酸后,体系的共振光散射增强,在364.0nm处,存在一共振光散射增强峰,其增强强度(△IRLS=I-I0)与核酸浓度呈线性关系,据此建立了一种测定纳克级核酸的简便灵敏的方法.对于fsDNA,方法的线性范围为27.0～625ng/mL,检出限为8.1ng/mL;对于ctD NA,方法的线性范围为39.0～500ng/mL,检出限为11.7ng/mL;对于yRNA,方法的线性范围为59.0～375ng/mL,检出限为17.7ng/mL.建立的方法已用于六种合成样品的测定,结果令人满意.

Determination of Nucleic Acids at Nanogram Levels with Pyronine Y by a Resonance Light-Scattering Technique

Based on the enhancement of resonance light scattering(RLS) of Pyronine Y(PY) by nucleic acids,a new quantitative determination method for nucleic acids in the nanogram range has been developed.In the pH range 11.5-12.0,the RLS of PY is greatly enhanced by nucleic acids,with the maximum scattering peak located at 364.0nm.The enhanced intensity of RLS,△IRLS,was found to be proportional to the concentration of nucleic acids in the range 27.0～625 ng/mL for fish sperm DNA,39.0～500 ng/mL for calf thymus DNA and 59.0～375 ng/mL for yeast RNA.The limits of determination were 8.1 ng/mL for fish sperm DNA,11.7 ng/mL for calf thymus DNA and 17.7 ng/mL for yeast RNA.Six synthetic samples were determined satisfactorily.The assay is convenient,rapid and inexpensive.