Living in a Material World
Material choice is imperative to sample prep success; here are some of the key considerations that chemists must make – and why
Verónica Pino | | Opinion
There is no doubt that many of the current advances in sample preparation methods, particularly in the microextraction field, have taken place in parallel with those occurring in material science. As a result, a variety of novel solvents – such as ionic liquids, magnetic ionic liquids, and deep eutectic solvents, among others – have facilitated the development (or improvement) of several liquid-phase (micro)extraction methods. In the same manner, solid materials such as magnetic nanoparticles, carbon-based materials, metal-organic, and covalent-organic frameworks are starting to occupy a privileged position as efficient sorbents in many solid-phase (micro)extraction approaches.
The success of sample prep materials relies on designing and tailoring these materials to possess certain properties. Some properties are desirable for specific analytical applications. They can be tuned to be hydrophobic or hydrophilic, water-soluble or insoluble, with a modulable degree of porosity and surface area, with certain functional groups in their structures that facilitate further interactions with target analytes, and so on. The full list is very impressive indeed – and these materials can also be combined to form composites, giving further mixed or combined properties.
Another important aspect to consider when using novel materials in (micro)extraction methods is the resulting increase in the solvents and sorbents available to us. This expansion is clear and helps us to overcome limitations associated with traditional approaches. Additional characteristics of “greenness” are also associated with many novel solvents and sorbents for extraction; these help us to develop more sustainable analytical methods. And if these reasons seem insufficient to recognize the impact of materials science in analytical chemistry, then consider the interest that such multidisciplinary work can provoke from other fields!
But we cannot be blinded by success; it is important not to lose sight of what must still be improved. Simply incorporating a material into an analytical method does not make it interesting or novel. The real questions we must ask when discussing novel materials are: does the incorporation of the material improve the performance of the resulting analytical method? Does the material perform better than others (including commercial materials)? Is the proposed material truly green (if claimed) in terms of its preparation and potential cytotoxicity? Does it possess adequate inter-batch reproducibility? And, when using composites, is each individual component necessary? Was the complexity of the final composite really needed? If we do not pay due attention to these concerns, then we run the risk of missing our opportunity to improve the sustainability and performance of our approaches with novel materials. These considerations ensure that chosen materials are fit for purpose and provide us with workable results in a way that isn’t detrimental to us or our environment.
Then there are also the questions we must ask beyond the remit of analytical chemistry. Were all materials properly synthesized and characterized? Was the yield reasonable? Was the preparation method affordable and sustainable? The list goes on.
Overall, decisions regarding the use of novel materials in sample preparation should be based in their design and selection for specific analytical applications. Sadly, this is often not the case; much research opts to use any available material in seemingly random applications, irrespective of its suitability and design. It is our responsibility to adopt strong criteria in our studies rather than succumbing to research trends. We must not ride the bandwagon – we must guide it! We are visionaries and our expertise is invaluable. Let us use it for the betterment of our field – and our planet. And why not use the benefits gained to support other areas of research – say, material science – while we’re at it?
Sample Preparation Study Group and Network belongs to the Division of Analytical Chemistry of the European Chemical Society (DAC-EuChemS) and includes three working groups (WG): 1. Science and Fundamentals, 2. Automation, Innovation and Entrepreneurship, 3. Information Exchange and Networking.
The Sample Preparation Network welcomes new European and non-European regular members. Membership is open to individuals who subscribe to the objectives of the network and who are professionally engaged in or associated with sample preparation.
For more information please visit: https://www.sampleprep.tuc.gr/en/home