Sponges and Sponge-Like Materials in Sample Preparation: A Journey from Past to Present and into the Future

Abstract

Even though instrumental advancements are constantly being made in analytical chemistry, sample preparation is still considered the bottleneck of analytical methods. To this end, researchers are developing new sorbent materials to improve and replace existing ones, with the ultimate goal to improve current methods and make them more efficient and effective. A few years ago, an alternative trend was started toward sample preparation: the use of sponge or sponge-like materials. These materials possess favorable characteristics, such as negligible weight, open-hole structure, high surface area, and variable surface chemistry. Although their use seemed promising, this trend soon reversed, due to either the increasing use of nanomaterials in sample preparation or the limited scope of the first materials. Currently, with the development of new materials, such as melamine sponges, along with the advancement in nanotechnology, this topic was revived, and various functionalizations were carried out on such materials. The new materials are used as sorbents in sample preparation in analytical chemistry. This review explores the development of such materials, from the past to the present and into the future, as well as their use in analytical chemistry.

Pressure-Sensitive Conducting and Antibacterial Materials Obtained by in Situ Dispersion Coating of Macroporous Melamine Sponges with Polypyrrole

“…Polymer sponges are attractive substrates for the coating with conducting polymers due to their low weight, open-cell macroporosity, high specific surface area, chemical stability, and elasticity. This makes them good candidates for sorbents applicable in biomedicine, analytical chemistry, solar steam generation, energy storage, and especially in environmental issues, such as water-pollution treatment. − Melamine/formaldehyde sponges are commercially available, and they are used as flame-retardant sound-proofing and thermal insulation or as abrasive cleaners. The coating with polypyrrole endows them with additional properties, such as the conductivity, electroactivity, and ability to sense humidity or to adsorb organic dyes , and various pollutants, including oil spills and heavy-metal ions .…”

Reduced Graphene Oxide Aerogels Cartridges for Solid Phase Extraction of Benzotriazoles

“…The GS presents rGO sheets of a relatively big size in a random distribution that creates large empty spaces between them. Although the porosity formed in this structure is useful, its arrangement makes it extremely fragile, thus limiting its application [ 18 , 28 ]. On the other hand, the GAs have a better-defined porous structure attributed to the presence of RF species, which react with functionalities of the GO sheets acting as a crosslinking agent, providing resistance to the material obtained and benefiting their handling [ 25 ].…”

Recent Advances in Sample Preparation for Cosmetics and Personal Care Products Analysis

“…Another recently developed nanomaterials employed as SPE sorbent for cosmetics analysis is graphene sponge (GS). This material presents special characteristics such as negligible weight, open-hole structure, high surface area and variable surface chemistry [ 83 ]. It has been employed to extract benzotriazole UV filters from water and cosmetics [ 48 ].…”