Analysis of fullerene-based nanomaterial in serum matrix by CE

Current Application of Capillary Electrophoresis in Nanomaterial Characterisation and Its Potential to Characterise the Protein and Small Molecule Corona

Due to the increasing use and production of nanomaterials (NMs), the ability to characterise their physical/chemical properties quickly and reliably has never been so important. Proper characterisation allows a thorough understanding of the material and its stability, and is critical to establishing dose-response curves to ascertain risks to human and environmental health. Traditionally, methods such as Transmission Electron Microscopy (TEM), Field Flow Fractionation (FFF) and Dynamic Light Scattering (DLS) have been favoured for size characterisation, due to their wide-availability and well-established protocols. Capillary Electrophoresis (CE) offers a faster and more cost-effective solution for complex dispersions including polydisperse or non-spherical NMs. CE has been used to rapidly separate NMs of varying sizes, shapes, surface modifications and compositions. This review will discuss the literature surrounding the CE separation techniques, detection and NM characteristics used for the analysis of a wide range of NMs. The potential of combining CE with mass spectrometry (CE-MS) will also be explored to further expand the characterisation of NMs, including the layer of biomolecules adsorbed to the surface of NMs in biological or environmental compartments, termed the acquired biomolecule corona. CE offers the opportunity to uncover new/poorly characterised low abundance and polar protein classes due to the high ionisation efficiency of CE-MS. Furthermore, the possibility of using CE-MS to characterise the poorly researched small molecule interactions within the NM corona is discussed.

Capillary electrophoresis/inductively-coupled plasma-mass spectrometry: development and optimization of a high resolution analytical tool for the size-based characterization of nanomaterials in dietary supplements

We report the development and optimization of a system consisting of capillary electrophoresis (CE) interfaced with inductively coupled plasma mass spectrometry (ICPMS) for rapid and high resolution speciation and characterization of metallic (e.g., gold, platinum, and palladium) nanoparticles in a dietary supplement. Multiple factors, including surfactant type and concentration, pH of running buffer, and applied voltage, were investigated to optimize the separation conditions. It was found that by using the anionic surfactant sodium dodecyl benzenesulfonate (SDBS) in the running buffer the separation resolution was significantly improved, allowing for easy distinction of adjacent size fractions in a gold nanoparticle mixture with very small size differences (e.g., 5, 15, 20, and 30 nm). The type and concentration of the surfactant was found to be critical in obtaining sufficient separation while applied voltage and pH values of the running buffers largely affected the elution times by varying the electroosmotic flow. Quantum dots were used as mobility markers to eliminate the run-to-run variation. The diameters of the nanoparticles followed a linear relationship with their relative electrophoretic mobility, and size information on unknown samples could be extrapolated from a standard curve. The accuracy and precision of this method was confirmed using 10 and 30 nm gold nanoparticle standard reference materials. Furthermore, the method was successfully applied to the analysis of commercially available metallic nanoparticle-based dietary supplements, as evidenced by good agreement between the particle sizes calculated by CE/ICPMS and transmission electron microscopy (TEM).

Quantitation of nanoparticles in serum matrix by capillary electrophoresis

Sensitive and fast analytical techniques are needed to determine the concentration of nanoparticles in biological samples (e.g., blood and tissues) for biodistribution and toxicity studies. This chapter describes a method for the use of capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC) for the quantitation of fullerene nanoparticles in human serum matrix. Data on the fullerene-based nanoparticle carboxyfullerene (C3 fullerene) in human serum is presented as an example.

Nanotechnology, nanotoxicology, and neuroscience

Nanotechnology, which deals with features as small as a 1 billionth of a meter, began to enter into mainstream physical sciences and engineering some 20 years ago. Recent applications of nanoscience include the use of nanoscale materials in electronics, catalysis, and biomedical research. Among these applications, strong interest has been shown to biological processes such as blood coagulation control and multimodal bioimaging, which has brought about a new and exciting research field called nanobiotechnology. Biotechnology, which itself also dates back approximately 30 years, involves the manipulation of macroscopic biological systems such as cells and mice in order to understand why and how molecular level mechanisms affect specific biological functions, e.g., the role of APP (amyloid precursor protein) in Alzheimer's disease (AD). This review aims (1) to introduce key concepts and materials from nanotechnology to a non-physical sciences community; (2) to introduce several state-of-the-art examples of current nanotechnology that were either constructed for use in biological systems or that can, in time, be utilized for biomedical research; (3) to provide recent excerpts in nanotoxicology and multifunctional nanoparticle systems (MFNPSs); and (4) to propose areas in neuroscience that may benefit from research at the interface of neurobiologically important systems and nanostructured materials.

Characterization of nanoparticles for therapeutics

Nanotechnology offers many advantages to traditional drug design, delivery and medical diagnostics; however, nanomedicines present considerable challenges for preclinical development. Nanoparticle constructs intended for medical applications consist of a wide variety of materials, and their small size, unique physicochemical properties and biological activity often require modification of standard characterization techniques. A rational characterization strategy for nanomedicines includes physicochemical characterization, sterility and pyrogenicity assessment, biodistribution (absorption, distribution, metabolism and excretion [ADME]) and toxicity characterization, which includes both in vitro tests and in vivo animal studies. Here, we highlight progress for a few methods that are uniquely useful for nanoparticles or are indicative of their toxicity or efficacy.