有些高等医药院校的生化实验教材编有嘌呤硷的鉴定实验。我们使用这些教材,经多次实验发现,其中某些过程的实验设计和实验结果有值得商榷的地方,特提出研讨。使用上述教材中方法提取核酸钠并水解其组成成分后鉴定嘌呤,结果生成较多的白色凝乳状沉淀,放置空气中后呈灰褐色。我们认为此沉淀并非纯嘌呤沉淀。由于在提取核酸过程中加入了10％氯化钠,使提取物中带进了氯离子。当加入硝酸银鉴定嘌呤时,既生成了嘌呤银沉淀也生成了氯化银沉淀,氯化银具有感光性,见光作用后发生分解,变成 Some colleges and universities of biochemistry experimental textbook purportedly purine alkaline identification experiment. We use these materials, after many experiments found that some of the experimental design and experimental results are questionable place, special discussion. The use of the above materials in the method of extracting sodium and hydrolysis of its components after the identification of purines, resulting in more white curdled precipitate, placed in the air was brown. We think this precipitate is not pure purine precipitation. As the extraction of nucleic acids in the process of adding 10% sodium chloride, the extract into the chloride ion. When the addition of silver nitrate to identify purines, both generated silver purine precipitate also generated silver chloride precipitation, silver chloride with light, the role of light after the decomposition occurs, into