Naked-Eye Detection of Aluminum in Gastric Drugs on a Paper-Based Analytical Device

Abstract

This communication describes a method to detect aluminum in gastric drugs by the naked eye using a microfluidic paper-based analytical device (μPAD). Aluminum ions react with chrome azurol S (CAS) and cetyltrimethylammonium bromide (CTAB) to form a colored complex, which generates a colored band on the μPAD. A printed ruler can be used to measure the length of the colored band on an individual paper channel for the quantification of an aluminum ion. The μPAD system was designed for use in a modern instrumental analysis course taken by students majoring in Food Quality and Safety. This analytical protocol could also be modified to be used as a demonstration or laboratory experiment in a high school chemistry course with some simplifications to the procedures.