Izon Science

Izon Science is a company in Christchurch, New Zealand, that makes instruments for counting and sizing nanoparticles one at a time. In its best-known instruments each particle is driven through a single hole in a polyurethane membrane, and the hole is opened or closed by stretching the membrane. The method is called tunable resistive pulse sensing (TRPS). The Exoid, the company's TRPS instrument since 2021, measures particles from 40 nm to 11 µm across and is sold for extracellular vesicles, lipid nanoparticles and virus-like particles.^[1] In June 2026 Izon added the Pulsoid, which uses a silicon chip with a pore of fixed size.^[2][3]

The company dispatched its first instruments in late September 2009. By January 2010 it had shipped 23 of them to 8 countries.^[4] Its own account of the qNano, written when the Exoid was launched, says that "thousands of scientists in over 45 countries" had used it and that it was "featured in around 1500 scientific publications".^[5]

Izon was shipping adjustable pores nine years before demonpore, inc., the earlier name of Molecular Reality Corporation, was incorporated in 2018. The smaller company's adjustable pore works differently.

Izon says it was founded in New Zealand in 2005 and took its present name in 2008. It was first incorporated as Australo Ltd.^[6] The method it sells had been described in 2007 in a paper titled "Dynamically resizable nanometre-scale apertures for molecular sensing", which made a hole in an elastomeric membrane and opened and closed it by stretching.^[7] The first instruments left the company in September 2009, and in January 2010 it reported that it had "recently released" version 1.0 of the qNano and the qViro.^[4]

Izon's other product line is qEV, a family of size exclusion chromatography columns. Vesicles pass around the beads of the resin, while smaller proteins enter the beads' pores and come out later, so the columns separate one from the other without a centrifuge. The first, the qEVoriginal, was launched in 2014.^[6][8] In March 2021 the company discontinued the qNano Gold and replaced it with the Exoid, in which the software monitors the baseline current, the applied pressure and the size of each current dip, and makes adjustments that earlier instruments left to the user.^[9][5]

The Pulsoid followed in June 2026. Izon's page describes it as built on "a precision-manufactured silicon nanopore chip" whose "fixed pore geometry" gives repeatable single-particle measurements. It reports size, concentration and zeta potential for particles from 40 nm to 140 nm, "additional sizes coming", and is designed for lipid nanoparticles. The company says it needs a fraction of the Exoid's setup time.^[2] The ChristchurchNZ website's report of the launch says the instrument's core design was developed in Christchurch and that some specialist silicon components are made overseas.^[3]

TRPS applies the Coulter principle to a pore that can be adjusted. Two fluid cells of salt solution are connected only through the pore, and a voltage across it drives an ionic current. A particle that enters the pore displaces conducting liquid, and the current dips for as long as the particle is inside. A 2018 perspective on the method gives its range as "tens of nanometers through to micrometers".^[10]

The pore in the qNano is conical, not cylindrical, and is made in a polyurethane membrane held in a stretching mechanism.^[11] A particle is carried through by two influences at once, the electrophoretic pull of the voltage and the flow set by an air pressure applied across the pore.^[11] The depth of each dip scales with the particle's volume. A 2011 study of the method found the relation between volume and change in resistance to be linear, as Maxwell had suggested, and turned dips into diameters by first measuring carboxylated polystyrene beads of known sizes.^[12] The rate of dips gives the concentration, which is calibrated against reference beads in the same way.^[11]

Stretch is the adjustment. The qNano's pores are sold in sizes, the NP100, NP200 and NP400, which together cover about 50 nm to 1,000 nm, and each has a range of its own with some overlap.^[11] The Exoid gives 40 nm to 11 µm for size and concentration, and 40 nm to 2,000 nm when the zeta potential, a measure of the particle's surface charge, is also determined.^[1]

In 2014 a laboratory that counted vesicles in urine with a qNano published a study of how repeatable its measurements were. On a standard sample measured daily at a fixed stretch and voltage, 102 times, the smallest vesicle detected had a diameter of 128 ± 19 nm, a coefficient of variation of 14.8 percent. The authors concluded that the variation came from differences between pores, and wrote that "Because the tunable pores are made of polyurethane, both the tolerances on the molding process as well as on the fabrication of the pore itself are a challenge."^[11]

Their remedy was to hold the height of the dips from reference beads fixed and let the stretch vary. On three different pores the minimum detected diameter had a coefficient of variation of 15.5 percent with a fixed stretch and 4.5 percent with a fixed dip height.^[11] The paper also reports that the NP200 was the pore most used in that laboratory, because it was "the most sensitive pore with an acceptable pore clogging rate on our samples".^[11]

Izon's pore is one of three families of adjustable pore described in Mechanical nanopore. In 2007, the year of the elastomer paper, a group at the University of Michigan stretched silicone rubber until its brittle skin cracked into nanochannels whose width followed the strain.^[13] A patent application filed by Agilent Technologies in 2001 described an aperture made where the corner of one etched silicon hole meets the edge of another, moved with piezoelectric positioners.^[14]

The adjustable pore of Molecular Reality Corporation, the juxtapore, is made of stacked rigid membranes that slide over one another to set the opening. A science-magazine report on the design, published on October 8, 2026, notes that tunable pores already exist and names Izon.^[15] The company's field guide traces the history of pore sensing from the Coulter counter to the 1996 experiment that drove DNA through a protein pore and on to solid-state pores, and ends its account with "We are not the first, and we are not pretending to be."^[16] Its description of sliding occlusion is "mechanical control of the pore's size, in real time, by moving solid parts."^[16]

Izon also appears in The Hole World, the company's atlas of molecular-sensing groups and companies, among its 15 entries classed as instrument makers.^[17]

• Mechanical nanopore
• Resistive pulse sensing
• List of nanopore companies
• Juxtapore