Nanoparticle Tracking Analyzer

What is the Nanoparticle Tracking Analyzer?

A scattering-mode instrument that tracks Brownian motion of individual nanoparticles under a laser sheet to report number-weighted size distribution and particle concentration. It fits 30 to 1000 nm dilute suspensions such as liposomes, vesicles and colloids where concentration data are required.

Overview

The analyzer focuses a laser beam, commonly 488 nm or 532 nm, into a thin sheet in a sample chamber and records scattered light from particles with a sensitive CMOS camera at 30 frames per second or more. Software tracks the two-dimensional movement of each particle over typically 60 seconds and calculates the diffusion coefficient, then the hydrodynamic diameter by the Stokes–Einstein equation, with temperature and viscosity inputs. Because each particle is followed individually, polydisperse mixtures and subpopulations are resolved better than with ensemble methods, and concentration is obtained from counts per volume. The practical concentration window is 10⁷ to 10⁹ particles/mL, so most samples need dilution. The detection limit depends on refractive index: about 30 nm for silver, 50 to 70 nm for polystyrene and 70 to 100 nm for biological vesicles.

How does it work?

Nanoparticle tracking analysis illuminates a dilute suspension with a laser sheet and records the scattered light of individual particles with a camera; software follows each track and derives a diffusion coefficient, converted to hydrodynamic diameter with the Stokes–Einstein equation, and counts particles per millilitre in a known volume. Resistive pulse sensing passes particles through a nanopore in an electrolyte; each particle transiently reduces ionic current in proportion to its volume, giving size and concentration. Field-flow fractionation separates particles in a thin channel by diffusion under a cross-flow before in-line light scattering detectors measure size and molar mass. Nano flow cytometers use hydrodynamic focusing and sensitive side-scatter and fluorescence detection to phenotype single particles. Sample dilution and calibration with reference beads are essential.

What are the key features?

• Laser sheet illumination with scientific CMOS camera
• Automated tracking of several hundred particles per video
• Number-weighted size distribution and concentration per millilitre
• Temperature-controlled sample cell from 15 to 55 °C
• Automated camera level and threshold recommendations
• Syringe pump for repeatable flow-mode capture

What are the technical specifications?

A typical nanoparticle tracking analyzer configuration offers size range of 30–1000 nm (material dependent), concentration range of 10⁷–10⁹ particles/mL, laser of 488 nm or 532 nm, 40–100 mW, camera of sCMOS, ≥ 30 fps, sample volume of 0.3–1 mL and temperature control of 15–55 °C, ±0.1 °C. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Nanoparticle Tracking Analyzer is used in liposome and exosome size and concentration, viral particle counting, protein aggregate screening, nanoparticle formulation development and environmental colloids. Across the wider Nanoparticle Analyzers class, laboratories also deploy it for liposome and lipid nanoparticle characterisation, extracellular vesicle and exosome research and viral vector and vaccine particle counting.

Which standards and certifications apply?

Relevant standards and methods include ISO 19430, ISO 13322-1, ISO 22412, ISO/TS 21362, ASTM E2834, ISO 21363 and GB/T 19627. Certification candidates for this model are CE and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Nanoparticle measurements are very sensitive to sample preparation. Use particle-free, filtered diluents and clean glassware, and dilute to the instrument's optimum concentration window. Dust and bubbles produce false counts. Verify size and concentration with certified polystyrene or silica nanosphere standards at start-up and after changes of settings, and report camera level, detection threshold, temperature and number of tracks, because these parameters change results. Keep laser optics, flow cells and nanopores clean and stored as advised. Install in a stable, temperature-controlled room. Regulated work needs IQ/OQ/PQ, locked methods and audit trails.

How do I select the right Nanoparticle Tracking Analyzer?

Select nanoparticle tracking when you need particle concentration together with a number-weighted size distribution for dilute 30 to 1000 nm samples. Specify target material and refractive index, expected concentration, laser wavelengths, need for temperature control or flow mode, and data integrity requirements. For high-resolution or sub-30 nm work, consider other variants.

How does it compare with other Nanoparticle Analyzers variants?

Decide what the measurement must deliver: concentration and size distribution of polydisperse samples, fluorescent subpopulation counts, high-resolution separation of mixtures, or single-particle phenotype. Nanoparticle tracking suits 30 to 1000 nm particles at 10⁷ to 10⁹ particles/mL. Resistive pulse sensing gives high-resolution, refractive-index-independent size for conductive dispersions. Field-flow fractionation coupled to multi-angle light scattering resolves mixtures and aggregates. Nano flow cytometry is preferred when labelling and marker analysis are needed. Check detection limit versus your smallest particle, required dynamic range, sample volume, and optical property dependence. Consider whether applicable guidance such as ISO 19430 and regulatory expectations for liposomes or vaccines apply, and who will operate and maintain the system.