An investigation of the low-frequency (i.e., less than 5 THz), inter-molecular dynamics of three imidazolium-based ionic liquids-1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C4mim][NTf2]), 1-butyl-3-methylimidazolium dicyanamide ([C4mim][DCA]), and 1-ethyl-3-methylimidazolium dicyanamide ([C2mim][DCA])-is presented using two-dimensional (2D) Raman-THz spectroscopy combined with molecular dynamics (MD) simulations.
View Article and Find Full Text PDFTherapeutic proteins are commonly conjugated with polymers to modulate their pharmacokinetics but often lack a description of the polymer-protein interaction. We deployed limited proteolysis mass spectrometry (LiP-MS) to reveal the interaction of polyethylene glycol (PEG) and PEG alternative polymers with interferon-α2a (IFN). Target conjugates were digested with the specific protease trypsin and a "heavy" N-IFN wild type (IFN-WT) for time-resolved quantification of the cleavage dynamics.
View Article and Find Full Text PDFParametrizing energy functions for ionic systems can be challenging. Here, the total energy function for an eutectic system consisting of water, SCN, K and acetamide is improved vis-a-vis experimentally measured properties. Given the importance of electrostatic interactions, two different types of models are considered: the first (model ) uses atom-centered multipole whereas the other two (models and ) are based on fluctuating minimal distributed charges (fMDCM) that respond to geometrical changes of SCN.
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