Meerbusch: Particle Metrix, developers of versatile particle characterization solutions for the life sciences, report on the work in the Liu Laboratory at Augusta University which is studying exosomes where size and concentration are critical parameters.
Dr Yutao Liu is an Associate Professor in the Department of Cellular Biology & Anatomy at Augusta University. The research goal of his group is to identify potential biomarkers for several human diseases. As a human genetics research lab, they are interested in studying how exosomes and its contents contribute to the development of glaucoma, such as primary open-angle glaucoma and exfoliation glaucoma. They use human aqueous tumor and serum samples to explore exosomes and their contents. They are further interested in studying the role of exosomes in serum and other body fluids in relation to aging, smoking cessation and other age-related disorders. The Laboratory collaborates with many researchers interested in the study of exosomes.
Dr Liu’s group started to study exosomes in 2012. In the early days, they learned that it was very critical to know the size and the concentration of nanoparticles in their study samples prior to the characterization of protein and RNA contents. He selected the ZetaView® system from Particle Metrix as it provided quick, efficient and reliable measurements of particle size and concentration. Dr Liu said “Its innovative design with 11-position measurement throughout the cell enables the high accuracy and reliability of the actual measurement by avoiding measuring the same particles repeatedly. In addition, ZetaView measures zeta potential with the same instrument. After comparing ZetaView with other available platforms, we are confident that ZetaView matches to our research needs better than other commercial platforms. Having tried other systems at the core facility at UNC, Chapel Hill, we purchased our ZetaView in 2014 and now use it exclusively.”
Transmission electron micrographs of adenovirus Ad-RGD TK, magnetic nanoparticles (MNP), and MNP Ad-RGD-TK.
Size characterization of adenovirus and MNPs by transmission electron microscopy. All samples were negatively stained with phosphotungstic acid solution and observed under transmission electron microscope at different magnifications. (A) Adenovirus. (B) MNPs. (C, D) Adenovirus conjugated to MNPs. Bar size is 50 nm in A and D, and 200 nm in B and C. The upper panel represents the color-enhanced version of the actual micrographs in the lower panel.
Describing why he thinks the design of the instrument is particularly strong, Dr Liu continues: “In comparing to other particle characterization systems, ZetaView is superb in providing more accurate measurement about particle size and concentration. The 11-position measurement together with the 10x lens enables the measurement of larger volume in the actual sample by avoiding measuring the same particles again and again. The software interface is very user-friendly and Particle Metrix has provided great technical support to solve any requests we had for change. The recent improvements in the hardware and software algorithms make particle characterization much easier, less time-consuming and more accurate. Also, ZetaView is able to measure zeta potential very reliably. We have done hundreds of measurements on zeta potential. So far, we have characterized particle size and concentration with over 1,000 samples.”
Wang Y, Zhang L, Li Y, Chen L, Wang X, Guo W, Zhang X, Qin G, He SH, Zimmerman A, Liu Y, Kim IM, Weintraub NL, Tang Y. (2015) Exosomes/microvesicles from induced pluripotent stem cells deliver cardioprotective miRNAs and prevent cardiomyocyte apoptosis in the ischemic myocardium. Int J Cardiol 192:61-9. [abstract]
Shalaby SM, Khater MK, Perucho AM, Mohamed SA, Helwa I, Laknaur A, Lebedyeva I, Liu Y, Diamond MP, Al-Hendy A. (2016) Magnetic nanoparticles as a new approach to improve the efficacy of gene therapy against differentiated human uterine fibroid cells and tumor-initiating stem cells. Fertil Steril [Epub ahead of print]. [abstract]