Evaluation of cell disruption technologies on magnetosome chain length and aggregation behaviour from MSR-1.

Magnetosomes are biologically-derived magnetic nanoparticles (MNPs) naturally produced by magnetotactic bacteria (MTB). Due to their distinctive characteristics, such as narrow size distribution and high biocompatibility, magnetosomes represent an attractive alternative to existing commercially-available chemically-synthesized MNPs. However, to extract magnetosomes from the bacteria, a cell disruption step is required.

Defining the influence of size-exclusion chromatography fraction window and ultrafiltration column choice on extracellular vesicle recovery in a skeletal muscle model.

Extracellular vesicles (EVs) have the potential to provide new insights into skeletal muscle (SM) physiology and pathophysiology. However, current isolation protocols often do not eliminate co-isolated components such as lipoproteins and RNA binding proteins that could confound outcomes and hinder downstream clinical translation. In this study, we validated an EV isolation protocol that combined size-exclusion chromatography (SEC) with ultrafiltration (UF) to increase sample throughput, scalability and purity, while providing the very first analysis of the effects of UF column choice and fraction window on EV recovery.

Single Extracellular Vesicle Transmembrane Protein Characterization by Nano-Flow Cytometry.

Single particle characterization has become increasingly relevant for research into extracellular vesicles, progressing from bulk analysis techniques and first-generation particle analysis to comprehensive multi-parameter measurements such as nano-flow cytometry (nFCM). nFCM is a form of flow cytometry that utilizes instrumentation specifically designed for nano-particle analysis, allowing for thousands of EVs to be characterized per minute both with and without the use of staining techniques. High resolution side scatter (SS) detection allows for size and concentration to be determined for all biological particles larger than 45 nm, while simultaneous fluorescence (FL) detection identifies the presence of labeled markers and targets of interest.

T-cell trans-synaptic vesicles are distinct and carry greater effector content than constitutive extracellular vesicles.

The immunological synapse is a molecular hub that facilitates the delivery of three activation signals, namely antigen, costimulation/corepression and cytokines, from antigen-presenting cells (APC) to T cells. T cells release a fourth class of signaling entities, trans-synaptic vesicles (tSV), to mediate bidirectional communication. Here we present bead-supported lipid bilayers (BSLB) as versatile synthetic APCs to capture, characterize and advance the understanding of tSV biogenesis.

Measuring particle concentration of multimodal synthetic reference materials and extracellular vesicles with orthogonal techniques: Who is up to the challenge?

The measurement of physicochemical properties of polydisperse complex biological samples, for example, extracellular vesicles, is critical to assess their quality, for example, resulting from their production and isolation methods. The community is gradually becoming aware of the need to combine multiple orthogonal techniques to perform a robust characterization of complex biological samples. Three pillars of critical quality attribute characterization of EVs are sizing, concentration measurement and phenotyping.

Quality and efficiency assessment of six extracellular vesicle isolation methods by nano-flow cytometry.

Extracellular vesicles (EVs) have sparked tremendous interest owing to their prominent potential in diagnostics and therapeutics. Isolation of EVs from complex biological fluids with high purity is essential to the accurate analysis of EV cargo. Unfortunately, generally used isolation techniques do not offer good separation of EVs from non-EV contaminants.

The high-resolution structure of (+)-epi-biotin bound to streptavidin.

(+)-Epi-biotin differs from (+)-biotin in the configuration of the chiral center at atom C2. This could lead to a difference in the mode of binding of (+)-epi-biotin to streptavidin, a natural protein receptor for (+)-biotin. Diffraction data were collected to a maximum of 0.