Nano-Doped Monolithic Materials for Molecular Separation

Abstract

Monoliths are continuous adsorbents that can easily be synthesised to possess tuneable meso-/macropores, convective fluid transport, and a plethora of chemistries for ligand immobilisation. They are grouped into three main classes: organic, inorganic, and hybrid, based on their chemical composition. These classes may also be differentiated by their unique morphological and physicochemical properties which are significantly relevant to their specific separation applications. The potential applications of monoliths for molecular separation have created the need to enhance their characteristic properties including mechanical strength, electrical conductivity, and chemical and thermal stability. An effective approach towards monolith enhancement has been the doping and/or hybridization with miniaturized molecular species of desirable functionalities and characteristics. Nanoparticles are usually preferred as dopants due to their high solid phase dispersion features which are associated with improved intermolecular adsorptive interactions. Examples of such nanomaterials include, but are not limited to, carbon-based, silica-based, gold-based, and alumina nanoparticles. The incorporation of these nanoparticles into monoliths via in situ polymerisation and/or post-modification enhances surface adsorption for activation and ligand immobilisation. Herein, insights into the performance enhancement of monoliths as chromatographic supports by nanoparticles doping are presented. In addition, the potential and characteristics of less common nanoparticle materials such as hydroxyapatite, ceria, hafnia, and germania are discussed. The advantages and challenges of nanoparticle doping of monoliths are also discussed.

Adsorption Characteristics of Synthesized Polyelectrolytes onto Alumina Nanoparticles and their Application in Antibiotic Removal

“…The natural raw materials are gradually exhausted and the artificial sources are encountered with high-cost issues, complex modulation processes, and difficult reaction conditions. For these reasons, research based on the modification of adsorbents by material doping and particle size reduction , is so far in speedy development. Surface modification of nanoparticles by a polyelectrolyte shows high performance because it is effective and highly applicable in improving the durability and reusability of the material. , …”

ProFlow nano‐liquid chromatography with a graphene oxide‐functionalized monolithic nano‐column for the simultaneous determination of chloramphenicol and chloramphenicol glucuronide in foods

“…The use of nano‐doped monolithic columns has attracted considerable interest in molecular separation (Acquah et al., 2017; Nesterenko et al., 2013; Svec & Lv, 2015; Tang et al., 2014). In this study, GO nanoparticles (GONPs) were used due to the fact that the large surface area of the stationary phases may be an ideal support for advanced food analyses (e.g., CAP, CAPG analyses).…”

Graphene oxide‐octadecylsilane incorporated monolithic nano‐columns with 50 μm id and 100 μm id for small molecule and protein separation by nano‐liquid chromatography

“…The preparation and application of NPs incorporated monolithic columns have witnessed great interest in chromatographic separation [2,9,23,24]. In this study, MGONPs were prepared and used for the monolithic nano-column preparation due to their large surface area that can be considered as an ideal support for advanced chromatographic applications (e.g., protein analyses).…”

“…Recently, nanoparticles (NPs) have been used for the preparation of monolithic materials in order to get high resolution and separation performance due to the fact that NPs allow high stability, efficiency, and large surface area, which provide faster mass transfer as well as the grafting of their surface with various functional groups [8]. Various NPs such as carbon nanotubes, graphene oxide were used for monolith preparation [9][10][11]. Among them, graphene (G) and its oxidized product, graphene oxide (GO), are new carbon materials, which are used for monolith preparation.…”