The Opposite Effect of Water and <i>N</i>‑Methyl-2-Pyrrolidone Cosolvents on the Nanostructural Organization of Ethylammonium Butanoate Ionic Liquid: A Small- and Wide-Angle X‑Ray Scattering and Molecular Dynamics Simulations Study

Two series of mixtures of ethylammoniumbutanoate (EAB, [N_0 0 0 2]­[C₃CO₂]) in water and N-methyl-2-pyrrolidone (NMP) have been prepared at different molar fractions to assess the effect of these two polar solvents on the nanostructural order present in [N_0 0 0 2]­[C₃CO₂]. The small- and wide-angle X-ray scattering (SWAXS) pattern of the liquid in neat state shows a prepeak at <i>Q</i> = 0.513 Å^–1, which is associated with the aggregation of nonpolar alkyl chains of both cations and anions. Interestingly, the two solvents affect the nanostructure of [N_0 0 0 2]­[C₃CO₂] differently, though both are polar. In the case of water addition to the mixture, the prepeak shifts to lower <i>Q</i> values, while in NMP, it moves toward higher values. Also, the principal peaks move in opposite direction in both solvents. The underlying expansion (water) or contraction (NMP) of the solutions observed by the scattering experiments is discussed in terms of molecular dynamics (MD) simulations, which are in very good agreement with the observed patterns

Clinical characteristics of study participants.

a<p>Significantly different (p<0.05) when compared blood culture confirmed bacteremia.</p

TPTest results in different study groups.

*<p>>10 ELISA unit was considered a positive TPTest (see text).</p

Comparison of TPTest results using various techniques.

<p>(<b>A</b>) The TPTest was carried out using leukocytes recovered by various techniques: density gradient centrifugation, erythrocyte lysis buffer, and buffy coat separation. The Mann-Whitney U test was used to compare the responses of different blood cell separation methods. RBC, red blood cell. (<b>B</b>) Comparison of TPTest results using peripheral blood mononuclear cells incubated at 37°C in the presence or absence of supplemental CO₂. >10 ELISA units was considered a positive TPTest (see text).</p

Sensitivity, specificity (with 95% confidence intervals in parenthesis) of TPTest for diagnosing enteric fever.

a<p>Calculated using a two by two table.</p

Effect on TPTest results of different incubation periods of cells.

<p>The TPTest was done using lymphocyte supernatants after 24 and 48 hours incubation of peripheral blood mononuclear cells (PBMCs) at 37°C with supplemental CO₂. >10 ELISA units was considered a positive TPTest.</p