An optimized filling method for capillary DLS

Ruseva, Valentina; Jankevics, Hanna; Corbett, Jason C.W.

doi:10.1016/j.mex.2019.03.006

Cited by 5 publications

(6 citation statements)

References 1 publication

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“…Used widely across industrial and research applications, DLS is employed within many sectors, for example in the development and production of biopharmaceuticals, pharmaceuticals, drug delivery products, cosmetics, food, electronics and pigments. The attraction of using DLS for particle size characterisation lies in the speed of measurement, ease of sample preparation-often dispersions can be measured without dilution, and the wide size range-from subnanometre up to 10 μm diameter (Ruseva et al 2019). DLS measures the hydrodynamic size of the sphere with equivalent diffusion coefficient (ISO 2017a).…”

Section: Introductionmentioning

confidence: 99%

Nanoparticle number concentration measurements by multi-angle dynamic light scattering

et al. 2020

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We present the use of Multi-angle Dynamic Light Scattering (MADLS®) for the measurement of nanoparticle concentration. We describe the theory of the method and its application to nanoparticles made of gold, silica and polystyrene, with diameters ranging from 30 to 400 nm, and demonstrate some of the limitations with particles of sizes 500 nm and above. We evaluate the method accuracy, linearity and reproducibility, as well as the operational nanoparticle concentration and size range. We show that the concentration working range depends on the material’s optical properties, size and concentration. Here it is shown that the level of accuracy that can be expected for the concentration of particles is typically within 50% of the nominal value across a range of materials and sizes and, for some samples, within 20%. The repeatability of the measurements, in terms of relative standard deviation, is typically below 30%. A linearity of within 40% across a concentration range of 3·108 to 2·1011 mL−1 for concentration measurements was also demonstrated by using gold nanoparticles and gravimetric dilutions for method validation. Overall, we show that MADLS® is a rapid and straightforward method for the reproducible measurement of particle concentration, as well as size, requiring minimal sample preparation, without the need to calibrate using a pre-determined concentration series, and applicable to a broad range of materials. These features make it an ideal tool to support both development and quality control of particle materials for a broad range of applications.

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Section: Introductionmentioning

confidence: 99%

Nanoparticle number concentration measurements by multi-angle dynamic light scattering

et al. 2020

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“…Here, we want to note that our larger CS microgels seemed to be under the effect of gravitational settling during the DLS measurements, which could be the reason for their higher polydispersities (or overestimation of polydispersity) compared to the smaller microgels. Although the commonly quoted upper size limit for DLS is around 10 μm, it often is only achievable by increasing the viscosity of the continuous phase or by using capillary DLS [ 25 , 26 ]. In this study, however, we do not further discuss the matter and report the D h values as recorded and used for the calculation of δ.…”

Section: Resultsmentioning

confidence: 99%

Micron-Sized Silica-PNIPAM Core-Shell Microgels with Tunable Shell-To-Core Ratio

Kuk

Gregel

Abgarjan

et al. 2022

Gels

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Micron-sized hard core-soft shell hybrid microgels are promising model systems for studies of soft matter as they enable in-situ optical investigations and their structures/morphologies can be engineered with a great variety. Yet, protocols that yield micron-sized core-shell microgels with a tailorable shell-to-core size ratio are rarely available. In this work, we report on the one-pot synthesis protocol for micron-sized silica-poly(N-isopropylacrylamide) core-shell microgels that has excellent control over the shell-to-core ratio. Small-angle light scattering and microscopy of 2- and 3-dimensional assemblies of the synthesized microgels confirm that the produced microgels are monodisperse and suitable for optical investigation even at high packing fractions.

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“…The capillary sealing method in [2] , describes the use of a clay which is conveniently used by pushing the end of the capillary into the clay such that a “slug” of clay fills the open end of the capillary. This clay melts at around 40 °C, meaning that during a temperature trend, the sealing of the capillary is not effective with the melted clay either contaminating the sample or allowing the sample to escape from the capillary.…”

Section: Methods Developmentmentioning

confidence: 99%

“…All samples were loaded into new capillaries which were subsequently sealed using the method described below. Capillaries were loaded into the ZSU1002 capillary holder as described in [2] , ensuring that the sample was appropriately positioned. For comparative measurements, samples were also loaded into clean ZEN2112 low volume quartz cuvettes.…”

Section: Methods Protocolmentioning

confidence: 99%