Archimedes
Particle Metrology System
Archimedes is a new, highly innovative instrument which uses the technique of resonant mass measurement to detect and accurately count particles in the size range 50nm - 5µm, and reliably measure their buoyant mass, dry mass and size. Particularly useful for the characterization of protein aggregates in formulation or buffer, Archimedes is also able to distinguish between proteinaceous material and contaminants such as silicone oil by means of comparing their relative resonant frequencies and buoyant masses.
Overview
Archimedes is an innovative, high-performance system which harnesses the technique of resonant mass measurement in order to detect and count particles in the size range 50nm - 5µm and to measure particle mass and size. Archimedes is uniquely positioned to quantitatively measure protein aggregates within and beyond the range of 100nm - 1µm, highlighted as a particular concern for immunogenicity and product safety.
Central to Archimedes is a MEMS (Micro Electro-Mechanical Systems) technology sensor, allowing the highly sensitive, reliable and reproducible measurement of aggregates, one by one. Archimedes is also capable of providing information on sample concentration, viscosity, polydispersity, density and volume, and distinguishing between negatively buoyant proteinaceous particles and positively buoyant contaminating silicone oil droplets.
Parameters measured:
- Particle number.
- Particle size.
- Particle buoyant mass.
- Particle dry mass.
- Particle density.
- Particle surface area.
- Sample volume.
- Sample concentration (particles/mL).
- Sample density.
Key Benefits:
- Ideally positioned for biopharmaceutical manufacturers and developers.
- Unique and accurate particle counting capability in the size range 50nm - 5µm.
- Exquisite sensitivity: measurement of particle mass to 350ag.
- Highly accurate particle size measurement from 50nm to 5µm.
- Excellent size resolution, <20nm at 1µm diameter.
- Low sample consumption: only 100µL.
- Differentiation between negatively buoyant and positively buoyant particles.
- Capable of measuring high concentration samples (to 109 particles/mL) and high viscosity samples (to 100cP).
- Fast, NIST-traceable calibration.
- Highly reproducible results.
- Intuitive and flexible ParticleLab software.
How it works
Archimedes uses the technique of resonant mass measurement to count and characterize particles. At the heart of Archimedes is a MEMS (micro electro-mechanical systems) sensor. Two types of sensor: the Micro sensor and the Nano sensor, are available for various applications. Each sensor comprises a microfluidics network and a minute cantilever which resonates with a particular frequency. Embedded in this cantilever is a microfluidic channel. As the advanced fluidics system of Archimedes pushes sample through this channel, the resonant frequency of the cantilever alters. This shift in the frequency of resonance is measured by a laser, focused on the tip of the cantilever, which is then transmitted to a split photodiode detector.
Each particle which passes through the sensor causes a change in the resonant frequency, giving an accurate and precise measurement of the particle’s buoyant mass – whether positive or negative - in the sample. From this measurement, the mass, size (equivalent sphere), and surface area of the particle are calculated. Overall measurements are also made of sample concentration, density, volume, and polydispersity.
Accompanying Archimedes is ParticleLab software, offering flexibility and versatility in both instrument control and data manipulation and presentation. ParticleLab is straightforward and intuitive, enabling precise instrument control and adjustment and a range of data handling capabilities.
Specification
Archimedes is able to measure a wide range of parameters simply and quickly, following the principles of resonant mass measurement.
Measurement type 1: Particle Size
- Measurement Range:
- 50nm - 5µm.
- Accuracy:
- Better than +/- 1% on NIST traceable latex standards.
- Precision/Repeatability:
- Better than +/- 1% on NIST traceable latex standards.
- Resolution:
- Better than +/- 20nm at 1µm, polystyrene beads in H2O.
Measurement type 2: Particle Buoyant Mass
- Lower Limit of Detection:
- 350ag.
- Accuracy:
- Better than +/- 3% on NIST traceable latex standards.
- Precision/Repeatability:
- Better than +/- 3% on NIST-traceable latex standards.
Measurement type 3: Particle Counting/Sample Concentration
- Measurement range:
- 104 particles/mL – 109 particles/mL.
- Accuracy:
- Better than +/- 10% on NIST traceable latex standards.
- Precision/Repeatability:
- Better than +/- 5% on NIST traceable latex standards.
Measurement principle: Resonant Mass Measurement.
- Drawn Sample Volume (minimum):
- 100µL.
- Measured Sample Volume Range:
- 10nL - 10µL.
- Sample Viscosity Range:
- <1cP -100cP
- Accuracy in Fluid Density:
- <0.002g/cc for densities in range 0.8g/cc – 1.2g/cc.
- Patents granted:
- US 8087284 B2.
- Light source:
- 685nm, 35mW laser.
- Power: (V, Hz, VA)
- 110V or 220V.
Weight and dimensions:
- Dimensions: (W, D, H)
- 610mm x 585mm x 305mm.
- Weight: (kg)
- 23.6.
Operating environment:
- Temperature:
- 18°C – 25°C.
- Humidity:
- 35% - 80% non-condensing.
Software:
- Minimum computer specification:
- Intel Core i5 Processor, 4GB RAM, 250GB HD, CD-ROM or DVD +/-RW drive, Wide Screen Monitor. At least 4 high speed USB ports required.
- Operating platforms:
- Windows 7 Professional.
Accessories
A small range of accessories and spares are available for Archimedes, adding flexibility and ease-of-use to the system
Accessories and Spares
Two types of screw-top glass vial – 20mL and 40mL capacity - are available for use with Archimedes. By using the dedicated vial seals a snug fit to the instrument is created, enabling pressure to be maintained throughout Archimedes’ fluidics system.
- 20mL and 40mL screw-top glass vials.
- Vial seals create a pressure-tight fitting.
- Vials need only be finger-tight.
- Additional seals available for snug fitting of fluidics lines into reference and waste bottles.
- Inserts such as eppendorf tubes may be used for smaller sample volumes inside 20mL vial.
- Sample may be drawn directly from a syringe placed inside 40mL vial.
Both deuterated water and a detergent solution are provided for use with Archimedes. Deuterated water provides a fluid density gradient inside Archimedes’ fluidics system, and should be pre-mixed with deionized water for optimal operation of the system. Detergent is designed for use when Archimedes is measuring protein solutions and will clean both sensors and the internal fluidics network of the instrument.
- Pre-prepared, long-lasting detergent acts within seconds to remove stubborn aggregates and debris.
- Deuterated water is used in small volumes to provide a density gradient in Archimedes and keep sample flow moving in the required direction.
- Simple and intuitive use with Archimedes.



