Microwave Digestion for Colorimetric Determination of Total Si in Plant and Mineral Samples

作者：Liu Saihua; Xie Yunhe; Ji, Xionghui; Juan, Huang; Bocharnikova, E. A.; Matichenkov, V. V.^*

来源：Communications in Soil Science and Plant Analysis, 2018, 49(7): 840-847.

DOI：10.1080/00103624.2018.1435685

• Alkali fusion
• autoclave digestion
• microwave digestion
• plant sample digestion
• silicon

A new method for determining the soluble silicon (Si) concentrations in nonliquid plant and mineral samples was developed using sodium hydroxide (NaOH)-hydrogen peroxide (H2O2) matrix for microwave digestion (MWD-Na) followed by colorimetric Si testing. MWD-Na was compared with autoclave-induced digestion and alkali fusion. The data have shown no significant difference between these three methods. HNO3-H2O2 or HNO3-H2O2-HF microwave technique results in Si loss. The reduction of the total Si can be realized via low solubility of Si in the acid solutions or silicon tetrafluoride formation. The Mullen and Riley method for colorimetric testing of Si in a solution that uses ascorbic acid to reduce the silicomolybdate complex formed under acid conditions to an intensely blue complex was modified using iron sulfate. The combination of MWD-Na and modified colorimetric blue method provides cheap and valid data on determining the total Si in both plant and mineral samples.

• 出版日期2018
• 单位湖南省农业科学院