Fully Robotic Method for Characterization of Toxic Residues

Abstract

A fully automated method for the determination of toxic residues was developed using a robotic station. The robot performs the weighing of the solid sample and applies the standard leaching method based on continuous stirring with discontinuous pH monitoring and control by addition of acid solution for 24 h; it then filters the sample and prepares the different dilutions for application of the luminescence test which is monitored by aspiration of the solutions into the flow cell of a luminescence detector. The data from both the sample mass and dilution step are used together with those from the detector by the computer for calculation of the toxicity. The two manual procedures usually applied in routine laboratories were developed by the robotic station; the results obtained by both methods were compared with those provided by the manual method and showed excellent agreement. The main advantage of the proposed method is that it is fully automated as opposed to the constant human attendance (for at least 28 h) required by the manual method.

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