June 15, 2013 (Vol. 33, No. 12)
Nanotech Firm Finds New Use for Particle-Detection Technology in Exosome Counting
NanoSight had already established itself as a top-tier maker of nanoparticle detection machines three years ago when a group of researchers from the University of Oxford persuaded the company to think even smaller.
The group had been using flow cytometry in trying to detect exosomes, biological nanoparticles central to cell signaling in cancers, diabetes, and other diseases. That technology, however, couldn’t detect particles smaller than 300 nm, while the exosomes they were studying ranged from 30 to 100 nm. The Oxford researchers got the results they sought using NanoSight’s instruments, then told the company, which grasped the importance of their observation.
“We said, ‘Well, that’s very interesting,’ and they said, ‘No, you’re missing the point. Your ability to detect these particles, which are potentially biomarkers for a whole range of diseases, is more important than the whole rest of your business put together. This is a real big deal,’” NanoSight CEO Jeremy Warren recalled.
Today, most cancers, as well as neurodegenerative diseases, diabetes, and heart conditions, are among diseases potentially detectable early on through exosome counting. Exosomes are one of five applications that account for 60% of NanoSight’s sales; the other four are drug delivery, toxicology of nanoparticles, aggregation of therapeutic proteins, and its original application, viral particle counting.
NanoSight’s 2012 sales were £5.7 million ($8.6 million). NanoSight has grown sales by more than 60% annually, since 2005, and today it generates 90% of sales outside the U.K.
The company is based on technology invented by microbial biochemist Bob Carr, Ph.D., who co-founded the company and today serves as its CTO. Carr’s 20 year career at the U.K. Government Research Establishment at Porton Down, Centre for Applied Microbiology and Research (CAMR), led him into laser/fiber optics instrumentation, biophysics, and later nanotechnology—specifically the application of biophysical techniques in the detection and analysis of nanoparticles. Carr left CAMR in 1996 to form his own R&D consultancy, Macranal, which developed the principles behind the technology applied by NanoSight. The company was formed in 2003 by Carr and by John Knowles, now NanoSight’s chairman.
Carr’s Nanoparticle Tracking Analysis (NTA) detects and visualizes within liquids populations of nanoparticles as small as 10 nm—depending on the material, specifically the difference in refractive index between the particles and the solvent—then measures the size of each particle based on direct observations of diffusion. The particle-by-particle methodology produces higher-resolution particle size distributions than possible through traditional light scattering and other ensemble techniques. NTA also measures particle concentration, validating its data through video of the moving particles.
“Bob Carr’s ‘Eureka!’ moment was to recognize what he was seeing was the scatter from the individual virus particles, and their Brownian motion” recalled Warren, who joined NanoSight in 2004 as the company’s third employee. “We can pick up proteinaceous, aggregating particles and silica at about 35 nm. But if the particles are harder, like organometallics, the size may be about 20 nm. And the very smallest ones we can detect—gold, silver and our all-time favorite, nanodiamonds, which we see rarely, alas—those are about 10 nm.”
Since its inception, NanoSight has installed more than 600 systems worldwide, for customers that include pharma giants GlaxoSmithKline, Merck & Co., Novartis, Pfizer, and Roche, as well as numerous universities and research institutes.
In therapeutic proteins, Warren said, customers are looking to enumerate the number of aggregates while seeking insight into how aggregation occurs at its earliest stages.
NanoSight’s applicability in drug delivery, he added, is its ability to accurately and rapidly size liposomes in water, using small volumes, very little sample preparation, and the tracking of their Brownian motion. NanoSight works well on the range of particles used for nano-scale drug delivery which include polymer carriers, prodrugs, and liposomes.
“Drug discovery used to use electron microscopy and dynamic light scattering, and they still do. But with NanoSight, they can get a result in about three minutes, and can immediately understand, when they look at one of their samples in liquids, whether there are actually any there; whether or not the particles are aggregated; the range of sizes and concentrations, as well as Zeta potential and an indication of nonsphericity,” Warren said
NanoSight’s instruments include the LM10, which uses a laser light source to illuminate nanoscale particles within 0.3 mL samples introduced with a disposable syringe; the LM10-HS, which resembles the LM10 but is equipped instead with a scientific complementary metal-oxide-semiconductor (sCMOS) camera; and the NS500, which analyzes liquid samples with the addition of automated dilution and cell-flushing.
In recent months, NanoSight’s product list, as with its applications, have reflected a company thinking smaller. NanoSight’s newest instrument, the NS300, introduced in March, measures just 40 cm (15.75 inches) by 25 cm (9.8 inches), compared with the larger desktop version.
NS300 features include a sCMOS camera, on-board temperature control, the ability to measure viscosity from 0–5 centipoise, and a laser block that can be upgraded to a motorized fluorescence disc capable of presenting up to six different fluorescent filters. The sample chamber and laser block are designed to be removed easily for cleaning and high-throughput.
Unlike many manufacturers, which scramble through marketing to meet customer demand, Nanosight says its success has come from honing new technologies, then evolving with users as they grasp how best to apply them.
“If we were to go back six or seven years ago, we could write a really good strategic plan on how we would look for specific customer segments that would be emerging. But that would be with hindsight, frankly nonsense. What happens in practice with a new technology is you simply don’t know what it is for. And the technology came first here,” Warren said.
Nanoparticle Tracking Analysis (NTA) visualizes, measures, and characterizes virtually all nanoparticles (10–2,000 nm). (A) The particles present in liquid illuminated by the laser. (B) The individual tracks of each particle. (C) The distribution of the particles under study.
NanoSight
Location:
Minton Park, London Rd.,
Amesbury, Wiltshire, SP4 7RT, U.K.
Phone: 44 1980 676 060
Website: www.nanosight.com
Principal:
John Knowles, Chairman
Jeremy Warren, CEO
Number of Employees: 47
Focus:
NanoSight manufactures instruments that measure and characterize virtually all nanoparticles, using its NanoParticle Tracking Analysis technology to analyze particle size, concentration, zeta potential, and aggregation, while a fluorescence mode provides speciation of labeled peptides.
