Adsorption Properties of Bovine Serum Albumin on Micron/Nano Calcium Oxalate Monohydrate and Dihydrate Crystals

作者：Wen Xiao-Ling; Ouyang Jian-Ming^*

来源：Chinese Journal of Inorganic Chemistry, 2016, 32(1): 103-110.

• nano
• micron
• calcium oxalate
• bovine serum albumin
• adsorption isotherms
• isoelectric point
• pH value

The adsorption isotherms of bovine serum albumin (BSA) on calcium oxalate monohydrate (COM) and calcium oxalate dehydrate (COD) crystals with a size of 100 nm and 3 mu m were detected, and Zeta potential of the crystals after adsorption of various concentration of BSA was measured. Adsorption quality change of BSA at different pH value were also measured. Results showed that the adsorption quality of BSA were positively related to the specific surface area of crystals, that was, following the order: COD-100nm > COM-100 nm >= COD-3 mu m > COM-3 mu m. However, after surface area normalization, the. adsorption order was COD-3 mu m > COM-3 mu m > COM-100 nm > COD-100 nm. It indicated that the crystal water and charge density on crystal surface of COM and COD also affected BSA adsorption. These adsorption isotherms were fitted better with Langmuir model, indicating a monolayer adsorption of BSA on micron/nano COD and COM surface. The isoelectric point of the four crystals followed an order: COM-100 nm (7.2)> COD-100 nm (6.7) >= COM-3 mu m (4.7)> COD-3 mu m (4.3), which indicated more serious aggregation of nanocrystals under pathophysiological, conditions (pH approximate to 6.3). The maximum BSA adsorption occurred at around isoelectric point of BSA (pH=4.8). The adsorption of BSA on micron/nano COM is related to the specific surface area of crystals, its surface charge, crystal aggregation, crystal water number, and the pH value of system. These results can help to clarify the effect of various urine microcrystalline and urine proteins on the formation of CaOx stones.

• 出版日期2016-1-10
• 单位暨南大学