Dr Thomas Glen, an expert in SEM and TEM, is dedicated to supporting other scientists to using this facility. A programme of outreach and training is making this facility available to academic and industrial researchers UK-wide. Why Light Scattering The scattering intensity is a function of the molecular weight and concentration. The availability of this combined suite of instruments is transforming the ability of soft matter scientists to see inside their samples routinely. Malvern Instruments & the Zetasizer Nano. As a technique, cryo-SEM-FIB is so new that we know of only two current instruments in the UK, neither of which is dedicated to the study of soft matter.
MALVERN ZETASIZER WAVELENGTH SERIES
Agilent 1200 Series Diode Array and Multiple Wavelength Detector UV-VIS DAD detektor (Agilent Technologies. This not only allows the user to expose desired sections at will, but also to build up a complete 3D picture (literally) by imaging the sample section by section to a resolution of 10 nm (100 times the size of atoms). Zetasizer Ultra (Malvern Panalytical Ltd). High power laser/alternative wavelength 50 mW, 532 nm. nu0.89e-3 refracindex 1.332 wavelength 632.8e-9 put wavelength in m.
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FIB is a powerful technique that uses a focused beam of charged atoms (ions) to cut and section specimens very accurately inside the SEM. cial flow cell for continuous DLS and also in Offline Mode using standard. the correlation data from the zetasizer nano Malvern instrument. Journal of Controlled Release 285 (2018) 35-45.The University of Edinburgh has been awarded EPSRC funding to purchase a cryo-SEM-FIB, housed in the School of Physics & Astronomy. Image adapted from reference: Claudia Conte, Francesca Mastrotto, Vincenzo Taresco, Aleksandra Tchoryk, Fabiana Quaglia, Snjezana Stolnik, Cameron Alexander. The colloidal stability of RR-NPs was lower than that of nRR-NPs under the different in vitro reducing conditions tested. with and without L-glutathione reduced (GSH) and dithiothreitol (DTT) are also shown. Size distribution curves of RRNPs and nRR-NPs nanoparticles incubated at 37☌ (30 min) in PBS and under different in vitro reducing conditions i.e. Both RRNPs and nRR-NPs had D H around 120 nm, low size PI and high negative zeta potential values thus both nps had similar colloidal properties. Bar graphs show particle size analysis (hydrodynamic diameter (D H) and polydispersity index (PI)) and zeta potential measurements of unloaded nanoparticles in water. Characterisation was carried out using a Zetasizer Nano ZS (Malvern Panalytical) instrument. For comparison, non redox-responsive nanoparticles PLGA-PEG nanoparticles (nRR-NPs) were also prepared. The RR-NPs were designed to change surface properties when entering tumour microenvironments, which would in turn enhance their cell internalisation and delivery of drug cargo. Redox-responsive PLGA (poly(lactic-co-glycolic acid)) - PEG (polyethylene glycol) nanoparticles (RR-NPs) were synthesised in a study aimed at developing programmable carrier nanoparticles for drug delivery into lung cancer tumour cells. Image 2: Size and zeta potential characterization of nanoparticles designed for drug deliveryĪn important step in the design of drug carrier nanoparticles is characterisation of particles size and surface change in appropriate environments. Hi-C Malvern Autosizer Malvern Autosizer 4800 Malvern Zetasizer 3 Malvern. Limo, ISAC, School of Pharmacy, University of Nottingham Pco S(a) f (10.44) SnkT (Or, 3ZTja rj viscosity A wavelength in. The two population sizes were identified with the 22 nm nps being the major/main population by number (%) distribution in the mixture.įigure courtesy of Marion J. The particle size characterisation was carried out using a DynaPro Plate Reader II (Wyatt) instrument. Large particles scatter much more light than smaller particles, thus the intensity (%) through to number (%) distributions may vary as shown in the exemplar data collected from a mixture of 22 and 200 nm polystyrene nanoparticles.
This is especially important where mixed population sizes are present. The figure above illustrates how a comparison of the different distributions gives a better understanding of the sample population. The distribution of particle sizes obtained from DLS measurements is fundamentally an intensity (%) distribution which can also be converted theoretically into volume (%) and number (%) distribution. Image 1: Size analysis of a mixture of polystyrene nanoparticles