Extraction of silicon from plant tissue with dilute HCl and HF and measurement by modified inductive coupled argon plasma procedures

Abstract

Detection of silicon (Si) in a dilute acid extract (1 M HCl+2.3 M HF) by inductive coupled argon plasma (ICAP) procedures was equivalent to the traditional silicomolybdous blue (colorimetric) method (r=+0.99). The glassware, nebulizer, spray chamber, and torch assembly of the ICAP instrument consisted of HF resistant materials. Comparison of HCl–HF extraction with autoclave-induced digestion (AID) for selected leaf reference materials indicated good agreement for corn stalks and bluegrass clippings, but not for apple or peach leaves. Recovery of added Si to various leaf tissue prior to HCl–HF extraction was excellent, ranging from 96.5 to 103.3%. Recovery of Si added to a closed nutrient solution by muskmelon plants varied from 97 to 100%. The dilute HCl–HF extraction of Si from rapidly growing plant tissue and measurement by ICAP methodology provides a rapid procedure, minimal chemicals, and a low correction factor reducing potential errors.

Acknowledgments