Method and apparatus for integrated measurement of the mass and surface charge of discrete microparticles using a suspended microchannel resonator
US8418535B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 2010 |
| Grant date | Apr 16, 2013 |
| Priority date | — |
| Expiry date | May 4, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/02863
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Measurements of the mass and surface charge of microparticles are employed in the characterization of many types of colloidal dispersions. The suspended microchannel resonator (SMR) is capable of measuring individual particle masses with femtogram resolution. The high sensitivity of the SMR resonance frequency to changes in particle position in the SMR channel is employed to determine the electrophoretic mobility of discrete particles in an applied electric field. When an oscillating electric field is applied to the suspended microchannel, the transient resonance frequency shift corresponding to a particle transit can be analyzed to extract both the buoyant mass and electrophoretic mobility of each particle. These parameters, together with the mean particle density, can be used to compute the size, absolute mass, and surface charge of discrete particles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.