机构地区: 中国科学院长春应用化学研究所
出 处: 《应用化学》 2010年第12期1434-1437,共4页
摘 要: 报道了谷氨酸晶体在L-半胱氨酸自组装单层上的成核和生长。在L-半胱氨酸单层的诱导作用下,通过改变溶液的pH值,可以制备出不同晶型的L-谷氨酸,这为控制谷氨酸的晶型提供了一个简单的方法。在pH值为2.0和2.5条件下,可得到六边形片状的β-谷氨酸,而在pH值为3.0和4.0时得到棱柱状的α晶体。XRD结果表明,α晶体内有少量的β-谷氨酸晶体出现,这可能来自于β-谷氨酸的"二次成核"。 In this paper,we report a facile approach to obtain different polymorphs of L-glutamic acid(LGA) by crystallization on self-assembled monolayers of L-cysteine under different pH conditions.The β-glutamic acid crystals with plate-like shape were obtained at pH=2.0 and 2.5,while α-glutamic acid crystals were prepared at pH=3.0 and 4.0.The XRD results show that a small amount of β-glutamic acid crystals appear in α-glutamic acid crystals,and they are probably from the secondary nucleation of the β-form.
领 域: [理学]