Izon Science Ltd. is a nanotechnology company that has developed instrumentation for nano-scale particle analysis. The company’s main products, qViro and qNano are in use in a wide range of research institutes and universities around the world.
The company was incorporated as Australo Ltd. on January 10, 2005, and renamed Izon Science Ltd. on November 17, 2008. Its headquarters are located in Burnside

Burnside, Canterbury

Burnside is a suburb of Christchurch, New Zealand, located southeast of Christchurch International Airport. As with most suburbs in Christchurch, it has no defined boundaries and is a general area.-History:...

, Christchurch

Christchurch

Christchurch is the largest city in the South Island of New Zealand, and the country's second-largest urban area after Auckland. It lies one third of the way down the South Island's east coast, just north of Banks Peninsula which itself, since 2006, lies within the formal limits of...

, New Zealand.

The measurement methodology used by Izon instruments is known as Scanning Ion Occlusion Sensing (SIOS), and utilizes dynamically resizable nanopores for real-time particle detection, quantitation and characterisation.

Applications include particle sizing, size distribution measurement, concentration analysis, real-time particle-particle interaction monitoring, and particle charge and mobility analysis.

Scanning Ion Occlusion Sensing

Scanning Ion Occlusion Sensing (SIOS) allows high-throughput single particle measurements as colloids and/or biomolecular analytes are driven through pores, one at a time. Particles crossing the nanopore are detected as a transient change in the ionic current flow, which is denoted as a blockade event with its amplitude denoted as the blockade magnitude. As blockade magnitude is proportional to particle size, accurate particle sizing can be achieved after calibration with a known standard.

Nanopore-based Measurement

Fixed geometry micro-scale apertures for particle detection have been used in a wide range of industrial applications since the invention by W.H. Coulter in the 1950s. Quantitative resistive pulse sensing of nanoparticles using Coulter-type counters has been shown to hold promise as a fast and accurate alternative to established sizing methods. Fixed pore size enables sensitive size measurements, but also limits analysis size range, which has implications for the measurable sample polydispersity.

Izon’s instrumentation overcomes this limitation by using size-tunable pores that allow for the optimisation of the resistance pulse magnitude relative to the background current by matching the pore-size closely to the particle-size. As detection occurs on a particle by particle basis, the true average and polydispersity distribution can be determined, without the averaging effects inherent in other size analysis technologies, such as dynamic light scattering.

Products

qViro and qNano were released as the world’s first commercial nanopore platform on 22 June 2009, representing the culmination of an extensive four-year R&D programme.

qNano

qNano is a bench-top instrument for the practical implementation of SIOS for fluid-borne analysis of nanometre-scale particles. This instrument incorporates a sensitive manual control system for Izon’s dynamically adjustable nanopores, enabling tunable, resistive pulse sensing over a wide particle size range (typically 50 nm – 10μm). Data acquisition software allows raw or filtered data to be viewed in real-time.

qNano has been designed to enable modularised upgrades such as full, software controlled automation of nanopore aperture adjustment, feedback control capability, pressurised control of flow and automated fluid control systems. User programmable modes allow stepwise increase in pore size to allow for preferential detection of different particle size ranges.

Uses of qNano include:

• Nanoparticle counting and gating
• Single particle control
• Nanoparticle relative size distribution analysis
• Analysis of distinct particle populations within a single sample
• Study of nanopores and nanofluidic systems

The qNano is sold as a full system ready for use including the base instrument, variable pressure module (VPM), fluid cell and a starter kit of nanopores, buffer solution and standard particle sets.

qViro

qViro is a virus counting instrument which provides previously unavailable capability to count and characterise individual virus particles in real-time. Using the sensitive manual control available in qViro, Izon’s dynamically adjustable nanopores can be tuned for a range of viral particle sizes, giving researchers the capacity for precision counting of viruses. Data acquisition software allows the virus count to be viewed in real-time. Disposable elements of the instrument enable issues of contamination to be handled according to researchers’ needs.

qViro has been designed to enable modularised upgrades such as full, software controlled automation of nanopore aperture adjustment, feedback control capability, pressurised control of flow and automated fluid control systems. The Instrument has a small footprint and fits easily into fume-hoods and biological containment facilities.

Uses of qViro include:

• Virus quantitation
• Immunodetection
• Molecular diagnostics
• Biomolecule analysis

The qViro is sold as a full system ready for use including the base instrument, variable pressure module (VPM), fluid cell and a starter kit of nanopores, buffer solution and standard particle sets.

Particle Sizing

qNano and qViro allow single particle measurement, and size distribution analysis of particle populations.

A discrete electrical signal is registered by the system each time a particle passes through the nanopore. Each individual particle signal is analysed and the make-up of the constituent populations is built up for the sample.

The magnitude of the electrical signal shows the volume of the particle (i.e. particle diameter). This allows rapid quantification of:

• Absolute size
• Size distribution and volume fraction analysis
• Resolving distinct populations within a sample mixture
• Assessment of polydispersity
• Aggregation and/or fragmentation levels
• Number and concentration of differently sized particles

Concentration

Evaluating the concentration of samples containing nano-sized particles is a key parameter for researchers in many fields. qNano and qViro can determine the concentration of a wide range of particle types including mono and polydispersed populations. It provides rapid and accurate determination of:

• Bacteria count
• Virus count
• Amount of drug
• Drug delivery dosage
• Amount of viral aggregates
• Amount of bacteria and cellular fragments

Reaction Dynamics

Reaction dynamics include – identification and analysis of particle-particle, particle-biomolecule, functionalization and aggregation interactions.

The beginning, middle and end of interactions can be effectively mapped by analysing subtle changes in particle size, surface charge and concentration simultaneously and on a particle-by-particle basis, allowing interaction dynamics and yields to be determined.

This can be applied to many different situations:

• Confirmation of binding interactions and functionalization
• Comparison of sample properties prior to and post interaction
• Small molecule detection and diagnostics – binding reactions between small molecules and the surface of particles allows detection of molecules that may otherwise be below the detection limit of the instrument
• Comparison of properties after exposure to different experimental conditions, such as pH, ionic strength, amount of added reagents and temperature
• Real time monitoring of binding interaction events, particle-by-particle, by combining reactants in the top fluid cell

The latest version of Izon’s Control Suite Software v2.1, allows improved analysis of reactions as they occur over time.

Research Fields

Research fields which are currently using the qNano and qViro platforms include drug delivery research, virology, vaccinology, gene therapy, haematology, chemistry, nanoscience and industrial research applications, e.g. microfluidics research

Microfluidics

Microfluidics deals with the behavior, precise control and manipulation of fluids that are geometrically constrained to a small, typically sub-millimeter, scale.Typically, micro means one of the following features:* small volumes...

. The qViro and qNano instruments can be used in a wide range of research environments including laboratories, clinics and in the field.

Nanopores

The nanopores are manufactured in a thermoplastic polyurethane cruciform using a proprietary technique. When fitted to the qNano or qViro instruments, the cruciform can be stretched evenly along the x and y axes to effect nanometre scale adjustments to the nanopore.

Fluid Cells

Each fluid cell is divided into two sections, the top and bottom sections of the fluid cell being connected together after the nanopore cruciform has been positioned between the two halves. The minimum volume of sample fluid required is 40μL.

Direct access points to the fluid in the upper and lower fluid cell compartments allows for easy and safe handling of samples.

An electrical connection is made to the bottom of the fluid cell via a shielded SMA connector. Silver chloride electrodes are fitted into the fluid cell. The fluid cell is designed with shielding to minimize electrical noise.

Variable Pressure Module

The variable pressure module (VPM) provides pressure and vacuum control of sample flow, complementing the electrophoretic operation of the qNano and qViro instruments. The application of pressure as a dominant force allows charged and uncharged particles to be detected by the system, as electrophoresis is no longer required for driving sample flow.

VPM also allows accurate concentration determination.

The additional sample flow generated by the VPM adds two orders of magnitude to the lower detection limit of the qNano and qViro instruments. Sample concentrations down to around 10^5 particles per mL may be measured.

By finely controlling and balancing electrophoretic and pressure forces exerted on the particle, detailed mobility and charge information can be extracted in a wide range of electrolyte environments.

The VPM was initially sold as an add-on module but now comes standard with qNano or qViro instruments.