LGC is an international life sciences measurement and testing company, providing reference materials, genomics solutions and analytical testing products and services. LGC works with customers within the pharmaceutical, agricultural biotechnology, food, environment, security and sports sectors, as well as those within government and academic organizations, to achieve scientific excellence. The vision at LGC is ‘Science for a Safer World’, and the company has been the host organisation for the UK’s Government Chemist function for over 100 years, serves as the National Reference Laboratory for a range of key areas, and houses the UK’s National Measurement Laboratory and Designated Institute for chemical and biochemical measurement.
In its function as Government Chemist, LGC provides scientific advice and analytical services in areas such as food and agriculture, health and pharmaceuticals. LGC’s role as a Designated Institute defines its credibility at the forefront of science and innovation and allows the company to offer unparalleled expertise on matters relating to policy and regulation. LGC addresses global measurement challenges within advanced therapeutics, diagnostics and safety and security to support industry needs, provide a sound basis for trade and improve quality of life.
The big challenges of nanomaterials
For several years, researchers at Malvern Panalytical (NanoSight) and LGC have worked closely together in order to resolve a particular issue relating to the measurement of nanomaterials.
Worldwide, there are currently more than 400 companies collectively making over 1300 commercial products which contain nanomaterials. The use of nanomaterials in products ranging from therapeutics to foods is growing year on year, and the global market for these items is predicted to increase to more than $75 billion by 2020. With this rapid growth in nanotechnology comes a range of responsibilities, including a requirement to measure the impact of nanomaterials on biological systems.
Nanomaterials are defined by recent EU regulation as products, including cosmetics, foods and biocides, with more than half of their constituent particles measuring between 1 nm and 100 nm in diameter. But the very benefits that nanoparticles can bring due to their small size, such as easy permeation of cell membranes and high reactivity with proteins, are details which may inherently also create health issues. Nanomaterials have immense potential for advances such as the improvement of human health, but this potential can only be realised if we are sure that they have no toxic effects, and toxicity can be very difficult to predict, especially for such novel materials. Therefore, a solid understanding of nanomaterials in terms of their behavior in relation to particle size and particle size distribution is crucial in order to satisfy regulatory requirements and enable effective labelling of these products.
Dr. Dorota Bartczak, Researcher in Inorganic Analysis at LGC explains: “Measurement methods and techniques that provide reliable data for researchers to understand how nanoparticles behave in complex biological systems are crucial for future human risk assessments and upcoming regulation, needed to ensure that the increasing use of nanomaterials does not endanger public health.”
Nanoparticle Tracking Analysis: a collaborative solution for the characterization of nanoparticles in complex matrices
A team of researchers from LGC partnered with scientists from Malvern Panalytical in order to investigate the ability of Nanoparticle Tracking Analysis (NTA) systems to measure nanoparticle size distribution and concentration in a complex matrix, when coupled to field flow fractionation and inductively coupled plasma mass spectrometry (FFF-ICPMS). This approach allows complex suspensions of nanomaterials to be characterized for their size, size distribution, charge, concentration, dissolution and elemental composition. NTA plays its part by visualizing and tracking Brownian motion in a unique particle-by-particle measurement, and provides the ideal insight for this characterization challenge.
“NanoSight uses Nanoparticle Tracking Analysis to measure particle size and number-based concentration simply and quickly, so it is clear exactly how many particles of any specific size are present,” said Dr. Bartczak. “Number-based measurements are critical to meet EU regulations relating to the testing of foods and cosmetics, but they also enable the direct study of critical processes such as agglomeration. With NanoSight we can see an increasing population of larger particles and a simultaneous reduction in particle concentration as agglomeration occurs. Such analysis makes it easier to reliably assess the characteristics of these complex nanoparticle systems. Recent software upgrades have enhanced NTA’s capabilities and we can now successfully study individual nanoparticle populations at the high serum concentrations that reflect conditions in nanotoxicology models.”
The result of this collaborative project was that researchers at LGC, in partnership with Malvern Panalytical, were able to accurately determine number-based concentration for silica nanoparticles of d < 100 nm in a complex biological matrix, with no requirement for chemical pre-treatment (Bartczak D., Vincent P. and Goenaga-Infante H., Anal. Chem. (2015) 87(11)5482-85).
Dr. Bartczak notes, “Our close collaboration with the development team at Malvern Panalytical has provided invaluable support for our European research programs, resulting in the development of new methodologies for accurate particle characterization in complex matrices, and also the improvement of currently-used strategies.”
Developing real solutions for research
LGC was an early adopter of NTA technology, and has worked consistently closely with the NanoSight product development team of scientists in improving NTA software so that it allows for more accurate measurement of nanoparticle populations in the high serum concentrations which reflect those encountered in toxicology models. LGC was also chosen by Malvern Panalytical to beta-test the flow-based concentration upgrade designed specifically for this purpose.
Phil Vincent, Development Scientist at Malvern Panalytical says, “LGC has provided expert application support to aid the development of our nanoparticle tracking technology. Their forward-thinking approach has made them willing candidates for beta testing new concepts and providing valuable feedback which has helped shape parts of our technology.”
NTA has been recognized by ASTM E2834 as a standard for the Measurement of Particle Size Distribution of Nanomaterials in Suspension, which notes that it is “one of the very few techniques that are able to deal with the measurement of particle size distribution in the nano-size region….routinely applied in industry and academia as both a research and development tool and as a QC method for the characterization of submicron systems.” (https://www.astm.org/Standards/E2834.htm). The current European Metrology Programme for Innovation and Research (EMPIR) project ‘Metrology for innovative nanoparticles’ will continue to assess NTA alongside other nanoparticle characterization technologies, including Dynamic Light Scattering, ICP-MS, small angle x-ray scattering Differential Centrifugal Sedimentation, in order to guide best practice for nanoparticle characterization. This research aims to help end users by supporting the development of high performance nanomaterials.