Platinum and Rhodium in Potato Samples by Using Voltammetric Techniques

Guideline for Analysis and Prevention of Contamination Catalysis

Over the last decades, numerous efforts have been made to replace metal catalysts with cheaper and earth-abundant alternatives or to completely exclude metals from cross-coupling reactions while maintaining high efficiency in the target transformation. However, follow-up studies often revealed the role of metal impurities in the catalytic process. Thus, active metal impurities can lead to mechanistic misinterpretations, and these could initiate erroneous research directives and lead to severe reproducibility problems. Milestone precedents of the impurity effect in cross-coupling reactions are well documented in the literature. Interestingly, this fallacy has reoccurred repeatedly over the years due to a lack of thorough mechanistic studies and appropriate research study schemes for identifying impurity effects. Herein, we propose a guideline to elucidate the real catalyst of future catalytic transformations, aiming to reveal the correct mechanism and help exclude the role of impurities in novel catalytic processes. Although this guideline mainly focuses on problems related to trace transition metals, it also offers the basis for more general catalyst research.

A simple and sensitive approach for the electrochemical determination of amaranth by a Pd/GO nanomaterial-modified screen-printed electrode

It is essential to develop easy-to-use sensors towards a better monitoring of food additives so that human health can be positively influenced. A type of critical food additive that is widely used in making soft drinks and diverse foodstuff is called amaranth. This study aimed at presenting a novel Pd/GO nanomaterial-modified screen-printed electrode (Pd/GO/SPE), which is responsible for providing a sensing interface during the process of specifying the electrochemical features of amaranth. The morphology and structure of the Pd/GO nanomaterial was investigated by Fourier-transform infrared spectroscopy, thermal gravimetric analysis, X-ray photoelectron spectroscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, scanning transmission electron microscopy, and high-resolution transmission electron microscopy. When the optimized conditions was adjusted, Pd/GO/SPE proved to be a capable sensor for conducting a very sensitive sensing towards the amaranth under a common working situation of 575 mV. In this regard, it was embarked on measuring some of the sensor features, including its sensitivity, linear dynamic range, and detection limit for amaranth with the values of 0.0948 μA μM-1, 0.08 μM-360.0 μM and 30.0 nM were obtained, respectively.