Resonant Mass Measurement
Method Introduction
Resonant Mass Measurement (RMM), also known as suspended microchannel resonator (SMR), is a valuable technique for sizing and quantifying particles.
RMM analysis is based on the Archimedes principle: The upward buoyant force acting on an object in a fluid equals the weight of the fluid displaced by the object. The sample solution flows through a microchannel inside a resonating cantilever, which resonates mechanically. When a particle passes the embedded channel, the resonation frequency will change proportionally to the particle’s buoyant mass. Positively buoyant and negatively buoyant particles can be discriminated as they increase or decrease the frequency of the cantilever. The buoyant mass is then converted into mass and finally into size based on the particle’s and fluid’s densities. The system can automatically determine the latter.
Applications
RMM is applicable for particles with a size from about 300 nm to 4 µm, depending on the density difference between particles and fluid. The upper particle concentration limit is roughly 10^7 particles/mL and is method- and sample-dependent.
One of the main applications for RMM is the quantitative discrimination between silicone oil droplets and protein particles. Such data are crucial for prefilled syringes and cartridges in any development phase since silicone oil (coated on the glass surface for plunger lubrication) can be present in the product as submicron or micrometer droplets. The differentiation is unambiguous, provided no other particle type is present in the sample.
RMM is also a valuable orthogonal tool for other particle analytics. Its light-independent measurement principle makes the technique robust against detection issues related to a particle’s refractive index, which is well known for light-based techniques, such as light obscuration (LO) and flow imaging microscopy (FIM) and, to some extent, also for light scattering-based techniques, such as dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA).
Quality and Biosafety Level
We provide all our analytical services with the highest quality standards. Experienced scientists carry out each project, and a scientific reviewer comprehensively checks every report or data presentation.
We offer this technology with the following quality and biosafety levels:
R&D level
We offer this method under R&D. Our GRP system assures the highest-quality research standards.
Up to biosafety level 2
This method can be applied to nucleic acids, viruses, cells, viral vectors, including lentiviruses, and more.
Analytical Method Development, Qualification and Validation
For common sample types, we can often apply standardized methods with little setup effort. However, when needed, our experienced analytical experts create or optimize custom methods tailored to your active pharmaceutical ingredient, product type and development phase.
Talk to Our Experts or Request a Quote
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