Recent advances and applications of synthetic diamonds in solid-phase extraction and high-performance liquid chromatography

Since the advent of diamond-based adsorbents in the late 1960s, the interest in their use for solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) has steadily increased. This is primarily due to their unique properties, such as extreme chemical and thermal stability, high mechanical strength and biocompatibility, and complex mixed-mode retention mechanisms. Currently, the most commonly used synthetic diamonds in SPE and HPLC are detonation nanodiamonds (DND), high-pressure high-temperature (HPHT) diamonds, and chemical vapour deposition (CVD) diamonds. These diamonds have been either used as individual particles (in both modified and unmodified forms), or for surface modification, or entrapped within composites and core-shell particles to develop new diamond-based adsorbents. These diamond-based adsorbents have been used for a variety of applications, including streamlined proteome analysis; extraction of anions, cations, actinides, uranium, lanthanides, alkaline earth metals, transition metals, and post-transition metals; and development of reversed-phase, normal phase, hydrophilic interaction, ion chromatography, and mixed-mode liquid chromatography columns, to name but a few. These varied applications of different types of diamonds are typically governed by their specific properties. This review discusses the various surface and bulk properties of DND, HPHT diamonds, and CVD diamonds that facilitate or limit their use in different SPE and HPLC based applications. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

Diamond-based adsorbents have gained increasing interest in solid-phase extraction and high-performance liquid chromatography due to their unique properties such as extreme stability, high mechanical strength, and complex retention mechanisms. Different types of diamonds, including detonation nanodiamonds, high-pressure high-temperature diamonds, and chemical vapour deposition diamonds, have been used for various applications in proteome analysis, extraction of metals, and development of different types of liquid chromatography columns. The specific surface and bulk properties of these diamonds play a key role in determining their suitability for different applications in SPE and HPLC.