Preparation and Characterization of Two Different Liposomal Formulations with Bioactive Natural Extract for Multiple Applications

Liposomes continue to attract great interest due to their increased bioavailability in the body and because the substances encapsulated are protected while maintaining their effectiveness. The aim of this study is to obtain “giant” liposomes by lipid film hydration using a preparation formula with two different phospholipids, phosphatidylcholine (PC) and phosphatidylserine (PS). Firstly, the macro- and microscopic characterization, total phenols content and antioxidant capacity of the plant Stellaria media (L.) Vill. were assessed. Then, Stellaria media (L.) Vill. extract was encapsulated in both formulations (PCE and PSE) and the liposomes were characterized according to their morphology, size distribution and Zeta potential using optical microscopy and dynamic light scattering. The encapsulation efficiency (EE%) was determined using the Folin–Ciocalteu method and the values of both formulations were compared. PC and PCE liposomes with a diameter between 712 and 1000 nm and PS and PSE liposomes with a diameter between 58 and 1000 nm were obtained. The values EE% of Stellaria media (L.) Vill. extract for PCE and PSE were 92.09% and 84.25%, respectively.

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Characterization of gelification of chitosan solutions by dynamic light scattering

Carbohydrate Polymers ◽

10.1016/j.carbpol.2011.11.002 ◽

2012 ◽

Vol 87 (4) ◽

pp. 2376-2380 ◽

Cited By ~ 20

Author(s):

W.A. de Morais ◽

M.R. Pereira ◽

J.L.C. Fonseca

Keyword(s):

Light Scattering ◽

Dynamic Light Scattering

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Characterization of Recombinant Adeno-Associated Viruses (rAAVs) for Gene Therapy Using Orthogonal Techniques

Pharmaceutics ◽

10.3390/pharmaceutics13040586 ◽

2021 ◽

Vol 13 (4) ◽

pp. 586

Author(s):

Liam Cole ◽

Diogo Fernandes ◽

Maryam T. Hussain ◽

Michael Kaszuba ◽

John Stenson ◽

...

Keyword(s):

Gene Therapy ◽

Light Scattering ◽

Dynamic Light Scattering ◽

Viral Vector ◽

Structural Characteristics ◽

Genetic Material ◽

Label Free ◽

Gene Therapies ◽

Multiple Challenges

Viruses are increasingly used as vectors for delivery of genetic material for gene therapy and vaccine applications. Recombinant adeno-associated viruses (rAAVs) are a class of viral vector that is being investigated intensively in the development of gene therapies. To develop efficient rAAV therapies produced through controlled and economical manufacturing processes, multiple challenges need to be addressed starting from viral capsid design through identification of optimal process and formulation conditions to comprehensive quality control. Addressing these challenges requires fit-for-purpose analytics for extensive characterization of rAAV samples including measurements of capsid or particle titer, percentage of full rAAV particles, particle size, aggregate formation, thermal stability, genome release, and capsid charge, all of which may impact critical quality attributes of the final product. Importantly, there is a need for rapid analytical solutions not relying on the use of dedicated reagents and costly reference standards. In this study, we evaluate the capabilities of dynamic light scattering, multiangle dynamic light scattering, and SEC–MALS for analyses of rAAV5 samples in a broad range of viral concentrations (titers) at different levels of genome loading, sample heterogeneity, and sample conditions. The study shows that DLS and MADLS® can be used to determine the size of full and empty rAAV5 (27 ± 0.3 and 33 ± 0.4 nm, respectively). A linear range for rAAV5 size and titer determination with MADLS was established to be 4.4 × 1011–8.7 × 1013 cp/mL for the nominally full rAAV5 samples and 3.4 × 1011–7 × 1013 cp/mL for the nominally empty rAAV5 samples with 3–8% and 10–37% CV for the full and empty rAAV5 samples, respectively. The structural stability and viral load release were also inferred from a combination of DLS, SEC–MALS, and DSC. The structural characteristics of the rAAV5 start to change from 40 °C onward, with increasing aggregation observed. With this study, we explored and demonstrated the applicability and value of orthogonal and complementary label-free technologies for enhanced serotype-independent characterization of key properties and stability profiles of rAAV5 samples.

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Characterization of Polymer Solutions Containing a Small Amount of Aggregates by Static and Dynamic Light Scattering

Macromolecules ◽

10.1021/ma0213899 ◽

2003 ◽

Vol 36 (6) ◽

pp. 2093-2102 ◽

Cited By ~ 48

Author(s):

Masaaki Kanao ◽

Yasuhiro Matsuda ◽

Takahiro Sato

Keyword(s):

Light Scattering ◽

Dynamic Light Scattering ◽

Polymer Solutions

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Characterization of Concentration-Dependent Gelation Behavior of Aqueous 2,2,6,6-Tetramethylpiperidine-1-oxyl−Cellulose Nanocrystal Dispersions Using Dynamic Light Scattering

Biomacromolecules ◽

10.1021/acs.biomac.8b01689 ◽

2018 ◽

Vol 20 (2) ◽

pp. 750-757 ◽

Cited By ~ 9

Author(s):

Yaxin Zhou ◽

Shuji Fujisawa ◽

Tsuguyuki Saito ◽

Akira Isogai

Keyword(s):

Light Scattering ◽

Dynamic Light Scattering ◽

Cellulose Nanocrystal ◽

Gelation Behavior

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Detection Limits of DLS and UV-Vis Spectroscopy in Characterization of Polydisperse Nanoparticles Colloids

Journal of Nanomaterials ◽

10.1155/2013/313081 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 155

Author(s):

Emilia Tomaszewska ◽

Katarzyna Soliwoda ◽

Kinga Kadziola ◽

Beata Tkacz-Szczesna ◽

Grzegorz Celichowski ◽

...

Keyword(s):

Light Scattering ◽

Dynamic Light Scattering ◽

Point Of View ◽

Spectroscopy Analysis ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Vis Spectroscopy ◽

The One

Dynamic light scattering is a method that depends on the interaction of light with particles. This method can be used for measurements of narrow particle size distributions especially in the range of 2–500 nm. Sample polydispersity can distort the results, and we could not see the real populations of particles because big particles presented in the sample can screen smaller ones. Although the theory and mathematical basics of DLS technique are already well known, little has been done to determine its limits experimentally. The size and size distribution of artificially prepared polydisperse silver nanoparticles (NPs) colloids were studied using dynamic light scattering (DLS) and ultraviolet-visible (UV-Vis) spectroscopy. Polydisperse colloids were prepared based on the mixture of chemically synthesized monodisperse colloids well characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM), DLS, and UV-Vis spectroscopy. Analysis of the DLS results obtained for polydisperse colloids reveals that several percent of the volume content of bigger NPs could screen completely the presence of smaller ones. The presented results could be extremely important from nanoparticles metrology point of view and should help to understand experimental data especially for the one who works with DLS and/or UV-Vis only.

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