The CONTIN algorithm and its application to determine the size distribution of microgel suspensions

Scotti, Andrea; Liu, Wei; Hyatt, John S.; Herman, Emily S.; Choi, Hyun Rim; Kim, J. W.; Lyon, L. Andrew; Gasser, Urs; Fernández‐Nieves, Alberto

doi:10.1063/1.4921686

Cited by 125 publications

(128 citation statements)

References 38 publications

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“…Size distribution analysis, using a continuous non-negative least squares (NNLS) fit of the autocorrelation function (CONTIN algorithm3536), was used to analyze polyplexes diluted in complete cell culture medium.…”

Section: Methodsmentioning

confidence: 99%

Size matters for in vitro gene delivery: investigating the relationships among complexation protocol, transfection medium, size and sedimentation

Pezzoli

Giupponi

Mantovani

et al. 2017

Sci Rep

108

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Although branched and linear polyethylenimines (bPEIs and lPEIs) are gold standard transfectants, a systematic analysis of the effects of the preparation protocol of polyplexes and the composition of the transfection medium on their physicochemical behaviour and effectiveness in vitro have been much neglected, undermining in some way the identification of precise structure-function relationships. This work aimed to address these issues. bPEI/DNA and lPEI/DNA, prepared using two different modes of addition of reagents, gave rise to polyplexes with exactly the same chemical composition but differing in dimensions. Upon dilution in serum-free medium, the size of any kind of polyplex promptly rose over time while remained invariably stable in complete DMEM. Of note, the bigger the dimension of polyplexes (in the nano- to micrometer range), the greater their efficiency in vitro. Besides, centrifugal sedimentation of polyplexes displaying different dimensions to speed up and enhance their settling onto cells boosted transfection efficiencies. Conversely, transgene expression was significantly blunted in cells held upside-down and transfected, definitively pointing out the impact of gravitational sedimentation of polyplexes on their transfection efficiency. Overall, much more attention must be paid to the actual polyplex size that relies on the complexation conditions and the transfection medium.

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Section: Methodsmentioning

confidence: 99%

Size matters for in vitro gene delivery: investigating the relationships among complexation protocol, transfection medium, size and sedimentation

Pezzoli

Giupponi

Mantovani

et al. 2017

Sci Rep

108

View full text Add to dashboard Cite

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“…[27] All the data were extracted from a global distribution in volume and the particle size was characterized with the D 50 value with its interquartile range (IQR). Laser light was from a Helium-Neon laser with 5 mW of output power at 633 nm, and the scattered light was detected at 90°.…”

Section: Dynamic Light Scatteringmentioning

confidence: 99%

Protamine Promotes Direct Electron Transfer Between Shewanella oneidensis Cells and Carbon Nanomaterials in Bacterial Biocomposites

Pinck

Jorand

et al. 2019

ChemElectroChem

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In this work, we studied the direct electron transfer reactions occurring in a biocomposite resulting from the self-assembly of Shewanella oneidensis MR-1 cells with different carbon nanomaterials (multi-walled carbon nanotubes, graphene oxide, Ketjen black or ordered mesoporous carbon) and protamine. The system has been studied with dynamic light scattering, scanning electron microscopy, epifluorescence microscopy and electrochemistry. Although protamine is known to have an antimicrobial activity, the interaction with carbon nanomaterials largely limits this effect. Formate and lactate oxidation and fumarate reduction have been studied. In the presence of 50 mM formate or 50 mM fumarate, the anodic current was lower than the cathodic one with the biocomposite prepared with protamine, while it was found similar with the biocomposite prepared with cytochromes c 1 or c 3 DvH, suggesting different electron transfer pathways. The redox potential observed for fumarate reduction (half-wave potential) was found between À 0.1 V and À 0.2 V vs. SHE with an onset potential close to 0 V vs. SHE with MWCNT, i. e. very close to 0.030 V vs. SHE, the formal redox potential for fumarate/succinate interconversion. A maximum current density in the range of 1 A m À 2 was reached for fumarate reduction. These data highlight a new way to promote direct electron transfer reactions in electroactive artificial biofilms.[a] Dr.

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“…With this in mind, we show both results obtained via cumulant and CONTIN analysis for DLS measurements [29]. The most commonly used analysis Is the cumulant analysis, where a polynomial is used to analyze the autocorrelation function, and the CONTIN analysis, which uses an inverse Laplace transformation to analyze the autocorrelation function, and is more reliable to analyze polydisperse samples.…”

Section: Da Urban Et Almentioning

confidence: 99%

“…Colloid and Interface Science Communications 22 (2018) [29][30][31][32][33] mean that the obtained results from TEM, TDA and DLS cannot be compared, on the contrary, yet the reader should keep in mind that the values are obtained by different techniques based on different models and assumptions. With this in mind, we show both results obtained via cumulant and CONTIN analysis for DLS measurements [29].…”

Section: Da Urban Et Almentioning

confidence: 99%

See 1 more Smart Citation

Taylor Dispersion of Inorganic Nanoparticles and Comparison to Dynamic Light Scattering and Transmission Electron Microscopy

Urban

Milošević

Bossert

et al. 2018

Colloid and Interface Science Communications

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A B S T R A C TTaylor dispersion analysis (TDA) is an analytical method that has so far mainly been utilized to determine the diffusion coefficient of small molecules, and proteins. Due to increasing interest in nanoscience, some research has been done on the applicability of TDA towards characterizing nanoparticles. This work aims to expand this knowledge and give insight into the range for which TDA can be used for nanoparticle characterization, focusing on various materials and sizes. The TDA setup shown in this work was successful in characterizing all engineered metallic, non-metallic nanoparticles, and proteins tested in this work. Results were compared to dynamic light scattering and electron microscopy, and were in good agreement with both methods. Taking into consideration the wide range of nanoparticle sizes that can be characterized, the minimal sample preparation, and sample volume, required and the simplicity of the method, TDA can be considered as a valuable technique for nanoparticle characterization.When looking at the huge array of properties that nanoparticles (NPs) possess, it is not surprising that they have found their way into a multitude of scientific research areas, and industrial applications [1]. Interesting NP phenomena are mostly governed by their size, and for many applications it is imperative that the NPs not only have a very specific size but also display a narrow particle size distribution [2]. For example, the heating properties of superparamagnetic iron oxide nanoparticles (SPIONs), which are being investigated as mediators of hyperthermia in cancer treatment, are dependent on their size and size distribution. Therefore, the characterization of nanoparticle size is crucial to ensure their functionality [3]. For this purpose, several analytical methods such as dynamic light scattering (DLS), NP tracking analysis (NTA), UV-Vis spectroscopy, field-flow fractionation, analytical ultracentrifugation, and transmission electron microscopy (TEM) have been utilized to characterize NP sizes and size distributions [4][5][6][7][8]. Each method has its advantages and disadvantages, and a combination of techniques is typically recommended to adequately characterize NPs [4]. For example, TEM provides information about NP core sizes, but cannot evaluate NP hydrodynamic diameters. Conversely, DLS and NTA can evaluate particle hydrodynamic diameter and colloidal stability, but are limited by the quality of light scattering and require a deeper knowledge of the theory and model-fitting to properly analyze the raw data. With scattering-based techniques, the limit of detection for NPs depends on the sensitivity of the detection of scattered light, and factors such as the material refractive index, particle size, shape and the wavelength used for detection. Furthermore, standard DLS measurements struggle with analyzing NPs in complex environments (e.g. proteincrowded suspensions, high particle concentration etc.) or samples where only limited sample preparation is possible [9][10][11]. There are pos...

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The CONTIN algorithm and its application to determine the size distribution of microgel suspensions

Cited by 125 publications

References 38 publications

Size matters for in vitro gene delivery: investigating the relationships among complexation protocol, transfection medium, size and sedimentation

Size matters for in vitro gene delivery: investigating the relationships among complexation protocol, transfection medium, size and sedimentation

Protamine Promotes Direct Electron Transfer Between Shewanella oneidensis Cells and Carbon Nanomaterials in Bacterial Biocomposites

Taylor Dispersion of Inorganic Nanoparticles and Comparison to Dynamic Light Scattering and Transmission Electron Microscopy

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