An Artificial Neural Network Assisted Dynamic Light Scattering Procedure for Assessing Living Cells Size in Suspension

Abstract

Dynamic light scattering (DLS) is an essential technique used for assessing the size of the particles in suspension, covering the range from nanometers to microns. Although it has been very well established for quite some time, improvement can still be brought in simplifying the experimental setup and in employing an easier to use data processing procedure for the acquired time-series. A DLS time series processing procedure based on an artificial neural network is presented with details regarding the design, training procedure and error analysis, working over an extended particle size range. The procedure proved to be much faster regarding time-series processing and easier to use than fitting a function to the experimental data using a minimization algorithm. Results of monitoring the long-time variation of the size of the Saccharomyces cerevisiae during fermentation are presented, including the 10 h between dissolving from the solid form and the start of multiplication, as an application of the proposed procedure. The results indicate that the procedure can be used to identify the presence of bigger particles and to assess their size, in aqueous suspensions used in the food industry.

Synthesis and Characterization of Amorphous Iron Oxide Nanoparticles by the Sonochemical Method and Their Application for the Remediation of Heavy Metals from Wastewater

“…TEM analysis requires the sample in the dry state whereas DLS allows the sample in the solvated state where solvent molecules associated with the nanoparticle surface (forms hydration layer) while estimating particle size by TEM, this hydration layer is not present hence lower particle size values was observed [ 59 , 60 ]. The average particle size of the synthesized IONPs is 550 nm and the PDI value is 0.015 which is in good agreement with the size of the IONPs.…”

“…The size of particle reported in DLS having higher values as compared to the TEM, due to the fact that in DLS, hydrodynamic sphere formed around the nanoparticles due to the difference is particle charge and dispersion medium under the influence of Brownian motion, the hydrodynamic diameter includes the core and any molecule adsorbed over the surface of the nanoparticle, which is why the particle size value seems to be higher. TEM analysis requires the sample in the dry state whereas DLS allows the sample in the solvated state where solvent molecules associated with the nanoparticle surface (forms hydration layer) while TEM analysis requires the sample in the dry state whereas DLS allows the sample in the solvated state where solvent molecules associated with the nanoparticle surface (forms hydration layer) while estimating particle size by TEM, this hydration layer is not present hence lower particle size values was observed [59,60]. The average particle size of the synthesized IONPs is 550 nm and the PDI value is 0.015 which is in good agreement with the size of the IONPs.…”

An Advanced Sensor for Particles in Gases Using Dynamic Light Scattering in Air as Solvent

“…If they scatter a coherent light beam, the wavelets interfere, producing a DLS time series. If the time series is analyzed with the procedure describes in Section 2.2 , an average hydrodynamic diameter in the DLS sense [ 37 ] is produced. Such a diameter should be understood as the diameter of the spherical particles that diffuse in air as the real particles do.…”

Sizing Particles in Gases by an Advanced Optical Procedure

“…A filtering procedure was used after the PS was computed, as in [20][21][22], that removed a window of 2 Hz width centered on 50 Hz frequency and the upper harmonics, as 50 Hz is the power grid frequency and such noise is ubiquitous. After filtering the FS spectrum, the Lorentzian line was fit to the spectrum as mentioned in Section 2, a0 and a1 were determined and, there from, radii of the particles using eq.…”