Enrichment of HDL proteome and phospholipidome from human serum via IMAC/MOAC affinity

High-density lipoproteins (HDLs) have anti-inflammatory and antioxidant properties and are potentially cardio-protective. Defective HDL function is caused by alterations in both the proteome and lipidome of HDL particles. As potential biomarkers, the development of analytical methods is necessary for the enrichment of HDLs. Therefore, a method for selective enrichment of HDLs using immobilized metal ion affinity chromatography (IMAC) and metal oxide affinity chromatography (MOAC) is presented. SPE-based isolation of HDLs from whole serum is adopted as an alternative to traditional ultracentrifugation methods followed by SDS–PAGE. The enrichment mechanism relies on isoelectric points of lipoproteins and metal oxide. Negatively charged lipoprotein particles interact with positively charged metal oxides and IMAC affinity, which acts as a cation. Identified proteins from HDL through MALDI–MS analysis are apo AI, AII, AIV, CI, CIII, E, J, M, H, serum amyloid A and other nonapoproteins that are part of HDL particles and perform cellular functions. This serum-based proteomics approach gives insight into the functional role of HDL. HDL-associated phospholipids have also been analyzed by LDI–MS. Results suggest that the adopted analytical strategy is a feasible idea to extract lipoproteins from serum. A comparative study of healthy and diseased samples using this approach will provide valuable information in future.     

Comparative study of the alignment method on experimental and simulated chromatographic data

One of the major problems in the signal comparison of chromatographic data is the variability of response caused by instrumental drifts and others instabilities. Measures of quality control and evaluation of conformity are inherently sensitive to shift. It is essential to be able to compare test samples to reference samples in an evolutionary analytical environment by offsetting the inevitable drift. Therefore, prior to any multivariate analysis, the alignment of analytical signals is a compulsory preprocessing step. During recent years, many researchers have taken a greater interest in the study of the alignment. The present paper is an updated review on the alignment algorithms, methods, and improvements used in chromatography. The study is dedicated to one‐dimensional signals. Several of the exposed methods have common theoretical bases and can differ through their optimization methods. The main issue for the operator is to choose the appropriate method according to the type of signals to be processed.     

Papain Loaded Poly(ε-Caprolactone) Nanoparticles<Emphasis Type="Italic">: In-silico and</Emphasis><Emphasis Type="Italic">In-Vitro</Emphasis> Studies

Papain is a protease enzyme with therapeutic properties that are very valuable for medical applications. Poly(ε-caprolactone) (PCL) is an ideal polymeric carrier for controlled drug delivery systems due to its low biodegradability and its high biocompatibility. In this study, the three-dimensional structure and action mechanism of papain were investigated by in vitro and in silico experiments using molecular dynamics (MD) and molecular docking methods to elucidate biological functions. The results showed that the size of papain-loaded PCL nanoparticles (NPs) and the polydispersity index (PDI) of the NPs were 242.9 nm and 0.074, respectively. The encapsulation efficiency and loading efficiency were 80.4 and 27.2%, respectively. Human embryonic kidney cells (HEK-293) were used for determining the cytotoxicity of papain-loaded PCL and PCL nanoparticles. The in vitro cell culture showed that nanoparticles are not toxic at low concentrations, while toxicity slightly increases at high concentrations. In silico studies, which were carried out with MD simulations and ADME analysis showed that the strong hydrogen bonds between the ligand and the papain provide stability and indicate the regions in which the interactions occur.     

Dose response of hydrazine – Deproteinated tooth enamel under blue light stimulation

The beta dose response and Optically Stimulated Luminescence (OSL) signal stability characteristics of human tooth enamel deproteinated by hydrazine reagent under blue photon stimulation are reported. Removal of the protein organic component of tooth enamel resulted in a higher OSL sensitivity and slower fading of OSL signals. The effect of chemical sample preparation on the enamel sample sensitivity is discussed and further steps to make this deproteinization treatment suitable for in vitro dose reconstruction studies are suggested.     

Solubility of hydrocarbons in water: Experimental measurements and modeling using a group contribution with association equation of state (GCA-EoS)

In this communication, new experimental data on the solubility of n-hexane, cyclo-hexane and iso-octane in pure water are reported. The data have been measured using a static-analytic technique that takes advantage of a Rolsi™ sampling device in the temperature range of 298–353 K and at pressures up to 0.5 MPa. The experimental data measured in this work at 298 K have been compared with some selected data from the literature and good agreement is found. A group contribution plus association equation of state, namely the GCA-EoS, is used to model the phase equilibrium of water + hydrocarbon (C₂ to n-C₆, cy-C₆, i-C₄ and i-C₈) system. The predictions of the model are found in good agreement with the experimental data measured in this work and some selected data from the literature.     

Determination of Lambda-Cyhalothrin and Malathion Residues in Locust by Gas Chromatography with Electron Capture Detection

Journal of Analytical Chemistry - A reliable, easy, and reproducible method was developed for the quantification of λ-cyhalothrin and malathion residues in desert locust. For the extraction, a...     

Preparation and dispersion stability of aqueous metal oxide nanofluids for potential heat transfer applications: a review of experimental studies

Journal of Thermal Analysis and Calorimetry - Nanofluids have recently attracted attention of many researchers due to their growing potential applications in heat transfer devices. They possess...     

Small amplitude dust-acoustic soliton energy in dusty plasmas with suprathermal polarization force

The effect of suprathermal polarization force on both linear and weakly nonlinear dust-acoustic solitary structures in a three-component dusty plasma is investigated. For this purpose, a new expression of the polarization force acting on dust particles that include the electronic suprathermal effect is derived. The results are applied to two different experimental dusty plasmas. We have found that the polarization force acting on the dust grains decreases as the electron suprathermality becomes more significant. In addition, we have shown that, for a given value of the spectral index κ , the polarization force magnitude fluctuates from one plasma to another. The changes arising in the propagation of small-amplitude dust-acoustic (DA) solitons due to the presence of this suprathermal polarization force are also analysed. Interestingly, an increase in the magnitude of the polarization force leads to an increase in the amplitude and width of DA soliton and provides more energy to the motion of this soliton.     

Oblique interaction of electrostatic nonlinear structures in relativistically degenerate dense magnetoplasmas

We have investigated the interaction of obliquely propagating ion acoustic solitary waves in a magnetoplasma with relativistically degenerate electrons. Using the quantum hydrodynamics model and by employing the extended Poincaré–Lighthill–Kuo technique, we have derived a set of Korteweg de Vries equations for two solitons. We have observed that the system under consideration allows the formation of only compressive solitons and their velocities remain in the sub-acoustic limit. Furthermore, phase shifts of solitons as a result of their interaction have been calculated. The phase shifts have been observed to be dependent on the obliqueness and the physical parameters of plasma. It has also been noticed that phase shifts remain negative for the whole range of parameters generally found in white dwarf stars. We have observed that the phase shifts enhance with the enhancement in number density, however, the converse happens when the magnetic field is enhanced. It has also been observed that the phase shift is slightly greater for the solitons that are less oblique as compared to their more oblique counterparts. Furthermore, we have estimated the spatial scales of interaction of solitons using the parameters found in white dwarf stars.