Tunable resistive pulse sensing (TRPS) is a single-particle technique used to measure the size, concentration and

zeta potential Zeta potential is the electrical potential at the slipping plane. This plane is the interface which separates mobile fluid from fluid that remains attached to the surface.is a scientific term for Electrokinetic phenomena, electrokinetic Electric ...

of particles as they pass through a size-tunable

nanopore A nanopore is a pore of nanometer size. It may, for example, be created by a pore-forming protein or as a hole in synthetic materials such as silicon or graphene. When a nanopore is present in an electrically insulating artificial membrane, membra ...

. The technique adapts the principle of resistive pulse sensing, which monitors current flow through an aperture, combined with the use of tunable nanopore technology, allowing the passage of ionic current and particles to be regulated by adjusting the pore size. The addition of the tunable nanopore allows for the measurement of a wider range of particle sizes and improves accuracy. TRPS Blockade

Technique

Particles crossing a nanopore are detected one at a time 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. This standard is composed of particles of a known size and concentration. For TRPS, carboxylated polystyrene particles are often used. Nanopore-based detection allows particle-by-particle assessment of complex mixtures. By selecting an appropriately sized nanopore and adjusting its stretch, the nanopore size can be optimized for particle size and improve measurement accuracy. Adjustments to nanopore stretch, in combination with a fine-control of pressure and voltage allow TRPS to determine sample concentration and to accurately derive individual particle zeta potential in addition to particle size information.

Applications

TRPS was developed by Izon Science Limited, producer of commercially available nanopore-based particle characterization systems. Izon Science Limited currently sell one TRPS device, known as the "Exoid". Previous devices include the "qNano", the "qNano Gold" and the "qViron". These systems have been applied to measure a wide range of biological and synthetic particle types including viruses and nanoparticles. TRPS has been applied in both academic and industrial research fields, including: *

Drug delivery Drug delivery involves various methods and technologies designed to transport pharmaceutical compounds to their target sites helping therapeutic effect. It involves principles related to drug preparation, route of administration, site-specif ...

research (e.g.

lipid nanoparticles Lipid-based nanoparticles are very small spherical particles composed of lipids. They are a novel pharmaceutical drug delivery system (part of nanoparticle drug delivery), and a novel pharmaceutical formulation. There are many subclasses o ...

and

liposome A liposome is a small artificial vesicle, spherical in shape, having at least one lipid bilayer. Due to their hydrophobicity and/or hydrophilicity, biocompatibility, particle size and many other properties, liposomes can be used as drug deliver ...

s) *

Extracellular vesicle This glossary of biology terms is a list of definitions of fundamental terms and concepts used in biology, the study of life and of living organisms. It is intended as introductory material for novices; for more specific and technical definitions ...

s such as exosomes *

Virology Virology is the Scientific method, scientific study of biological viruses. It is a subfield of microbiology that focuses on their detection, structure, classification and evolution, their methods of infection and exploitation of host (biology), ...

and

vaccine A vaccine is a biological Dosage form, preparation that provides active acquired immunity to a particular infectious disease, infectious or cancer, malignant disease. The safety and effectiveness of vaccines has been widely studied and verifi ...

production * Biomedical diagnostics *

Microfluidics Microfluidics refers to a system that manipulates a small amount of fluids (10−9 to 10−18 liters) using small channels with sizes of ten to hundreds of micrometres. It is a multidisciplinary field that involves molecular analysis, molecular bi ...

References

{{reflist, colwidth=30em Nanotechnology Nanoparticles