摘要:
自行设计新型消光池,研制了一种廉价的手持式消光光度计,并在此基础上建立了掺杂牛奶的现场检测方法.实验结果表明,所建立的方法无需对牛奶进行复杂处理,可对常见掺杂(如搀水、米汤、奶粉、豆浆、尿素等)牛奶和含重金属离子汞的牛奶,进行现场检测.由于采用新型消光池,有效地减小了蛋白质粒子因重力沉降所带来的误差,能够成功区分同密度劣质牛奶.该方法灵敏度高,对掺水牛奶的检出限低于2%,对重金属(如汞)的检出限为0.005μg/g.单个样品测定时间不到2 min,适合于牛奶品质的现场快速检测.
Abstract:
Based on Mie theory of light scattering of spherical particles, a novel homemade extinction cuvette was used to construct a handheld extinction photometer for in situ detection of milk adulteration without any complicated pretreatment of the milk samples. Adulteration of cow milk with various substances such as water, soup, powdered milk, soy milk, carbamide, heavy metal salts, etc. were in situ detected with minimal sample pretreatment. Surprisingly, the inferior milk adulterated with powdered milk, soup and/or other materials that could not be distinguished by a density meter was successfully differentiated in situ by the method reported. The detection limits of the method for spiked water and heavy metal such as mercury were lower than 2% and 0.005 μg/g respectively. The average time for single sample detection was less than 2 minutes using the current method, providing a practically useful tool for in situ gradation of milk quality.
下载:
京公网安备 11010202008159号