A centrifugal microfluidic platform prototype with an integrated membrane for gas diffusion is presented for the first time. The centrifugal platform allows multiple and parallel analysis on a single disk and integrates at least ten independent microfluidic subunits, which allow both calibration and sample determination. It is constructed with a polymeric substrate material and it is designed to perform colorimetric determinations by the use of a simple miniaturized optical detection system. The determination of three different analytes, sulfur dioxide, nitrite and carbon dioxide, is carried out as a proof of concept of a versatile microfluidic system for the determination of analytes which involve a gas diffusion separation step during the analytical procedure.

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A microanalyzer prototype for copper(II) ion monitoring in mining industrial processes is presented. The microanalyzer is designed as an assembly of different modules, each module being responsible for a unit operation. In order to optimize the industrial processes, the microanalyzer can automate all sample management, signal processing, and mathematical calculations and wirelessly transfer data to a control room. The determination of copper(II) ion is done using a colorimetric reaction and the microanalyser performs autocalibration by in situ dilution of a stock solution, matching the higher analyte concentration of the working range defined for the sample to be determined, using a multicommutation approach. The performance of the microanalyzer for monitoring copper(II) ion in water effluents of mining facilities was optimized in the working range from 1 to 10 mg/L to match Mexican environmental law regulations, which allow a maximum concentration of 4 mg/L of copper(II) ion in these circumstances.