Protein aggregation monitor

The evolutionary history of the NS4910 protein aggregation monitor (PAM)... 

Dong et al. [35] indicated that a successful lyophilized protein formulation is the preservation of the native conformation in the dried solid. They used FTIR as a tool to study lyophilized-induced unfolding and aggregation of proteins, namely, through the bands at 1620 cm to 1685 cm, common IR spectral features indicative of lyophilization- and temperature-induced protein aggregation, used to monitor and quantify aggregation even in the dried solid. 

Pavlova A, McCamey ER, Peterson DW, Dahlquist EW, Lew J, Han S (2009) Site-specific dynamic nuclear polarization of hydration water as a generally applicable approach to monitor protein aggregation. Phys Chem Chem Phys ll(31) 6833-6839... 

There are several types of experiments for which DLS is already well established as a technique. ° The increase in size and dynamics of aggregate formation can be investigated by DLS by monitoring the kinetics of the size distribution, which increases when both the protein aggregates and the monomers are present in the experimental probe at the same time. Since the scattered intensity is proportional to the molecular radius to the power of six, the results of particle sizing are shifted toward the size of the aggregate, which can thus be detected at very low concentration. The thermal stability of... 

Monitoring protein aggregation with ESI-MS allowed the evolution of small soluble oligomers to be observed and characterized in real time. However, a limitation of this approach is the uncertainty regarding the relationship between the fractional concentrations of oUgomeric species in solution and the relative abundance of ionic signal in ESI. 

There are different embodiments of SMSLS. They can contain flow cells, batch cells, or both. They can use lasers with beam splitters or individual lasers per cell. Cells can be in series, for applications where there is no tmbidity, in parallel when tmbidity is an issue, or some combination of the two. Other featmes are currently being added to SMSLS. Depolarized detection, for example, can monitor processes in which there are transitions from isotropic to anisotropic morphologies or vice versa, snch as nano- and micro-fibrillar modes of protein aggregation. 

The interest in vesicles as models for cell biomembranes has led to much work on the interactions within and between lipid layers. The primary contributions to vesicle stability and curvature include those familiar to us already, the electrostatic interactions between charged head groups (Chapter V) and the van der Waals interaction between layers (Chapter VI). An additional force due to thermal fluctuations in membranes produces a steric repulsion between membranes known as the Helfrich or undulation interaction. This force has been quantified by Sackmann and co-workers using reflection interference contrast microscopy to monitor vesicles weakly adhering to a solid substrate [78]. Membrane fluctuation forces may influence the interactions between proteins embedded in them [79]. Finally, in balance with these forces, bending elasticity helps determine shape transitions [80], interactions between inclusions [81], aggregation of membrane junctions [82], and unbinding of pinched membranes [83]. Specific interactions between membrane embedded receptors add an additional complication to biomembrane behavior. These have been stud-... 

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