The Massachusetts Institute of Technology (MIT) has developed a mass particle measurement tool around the attogram. The attogram is the millionth part of a microgram, scale to which belong the masses of viruses, some cellular components and synthetic nanoparticles. The system developed at MIT allows to measure its mass.
The researchers have explained that they have been based on another system developed previously at MIT itself. This system, called SMR (suspended microchannel resonator), is used to measure mass particles equivalent to cells. Presented in 2007, it measures the mass of the particles through a silicon channel. This channel is winged, empty and vibrates. When the particle passes, the frequency of the vibration changes and from there the mass of the particle is calculated.
Now, to measure particles of less mass than the cells, the entire system has been reduced and the measurement has had to be adjusted and other modifications made. For example, instead of the origin of the vibration being electrostatic, this time it is piezolectric. Thus they have managed to measure particles up to 30 times less mass than before, reaching a resolution of 0.85 attograms.
According to researchers, the system is capable of measuring 30,000 particles in 90 minutes. The work carried out has been published in the journal PNAS and has advanced that it has very interesting applications in nanomedicine.