UMass Lowell Improve Understanding of Nanomaterial Toxicology, Bacterial Biofilm Production at GMU

Post publication date: 
Tuesday, August 26, 2014

Two examples of studies, supported by scientific publications, realized using the qNano from Izon Science. The qNano is considered by the researcher community a dependable instrument in the field of nanoparticles characterization. The qNano is a reliable and robust instrument, which works with the Coulter principles on nanoparticles, allowing measurements on size, concentration, zeta potential and dynamic properties.

Researchers at UMass Lowell Improve Understanding of Nanomaterial Toxicology

Accurate characterization of engineered nanomaterials (ENM) is important to understanding their toxicity. Experimental errors resulting from inadequate characterization of dispersions and their impact on the delivered dose to cells are poorly documented and may contribute to irreproducible or conflicting results.

Prof. Dhimiter Bello's group at UMass Lowell explored for the first time the utility of nanopore based Tunable Resistive Pulse Sensing (TRPS) technology and optimized its use for characterization of engineered nanomaterial dispersions in cell culture medium containing serum, conditions applicable to in vitro nanotoxicology studies.

In close collaboration with Prof. Philip Demokritou of the Harvard School of Public Health (Director of the Center for Nanotechnology and Nanotoxicology), the group are applying advanced in vitro dosimetry models recently developed at Harvard to estimate the impact of changes in nanoparticle size distributions in cell culture media on the delivered dose to cells, and the subsequent changes in in vitro dose-response relationships and hazard ranking of nanomaterials.

Accurate size distribution measurements are paramount to understanding the impact on the ENM dose-response relationships. "TRPS offers competitive instrumental costs, portability, better accuracy, and the potential for extracting additional information on aggregate morphology, dynamic particle-particle and particle-biomolecule interactions."

qNano analysis of Bacterial Biofilm Production at George Mason University

Researchers at the National Center for Biodefense and Infectious Diseases, George Mason University recently received the qNano which they used in a new paper, Chung et al. 2014 "Chitinases Are Negative Regulators of Francisella novicida Biofilms" (Open Access).

Dr. Monique Van Hoek and colleagues determined the relative surface charge and size distribution analysis of wild-type Francisella novicida bacteria, and two chitinase mutants chiA and chiB using the device. The qNano utilizes Tunable Resistive Pulse Sensing technology to allow for a high-throughput, particle-by-particle, analysis of particle size, surface charge, and electrophoretic mobility.

qNano experiments were performed to determine if there were observable changes in size of Francisella novicida bacteria that did or did not express chitinase. Chitinase is thought to regulate biofilm expression, which may coat the bacteria with extracellular polymeric substance (EPS) in the absence of chitinase and thus alter their size.

The size distribution and relative surface charge analysis was performed using Izon Control Suite software. See Figures above. The authors found increased bacterial sizes and larger pore translocation times in chi mutants, suggesting that chitinases are involved in changes of the cell sizes and surface charges. In future studies, the qNano will be used to observe the sizes and the surface changes (zeta potential) in bacteria following treatment with antimicrobial peptides being studied.

Related products 

qNano Gold - IZON Science
The World’s Most Detailed Information for Each Individual Nanoparticle

Partner 

IZON Science