Role of Hansen solubility parameters in solid phase extraction

Improving the Separation Properties of Polybenzimidazole Membranes by Adding Acetonitrile for Organic Solvent Nanofiltration

In research on membranes, the addition of co-solvents to the polymer dope solution is a common method for tuning the morphology and separation performance. For organic solvent nanofiltration (OSN) applications, we synthesized polybenzimidazole (PBI) membranes with high separation properties and stability by adding acetonitrile (MeCN) to the dope solution, followed by crosslinking with dibromo-p-xylene. Accordingly, changes in the membrane structure and separation properties were investigated when MeCN was added. PBI/MeCN membranes with a dense and thick active layer and narrow finger-like macrovoids exhibited superior rejection properties in the ethanol solution compared with the pristine PBI membrane. After crosslinking, they displayed superior rejection properties (96.56% rejection of 366-g/mol polypropylene glycol). In addition, the membranes demonstrated stable permeances for various organic solvents, including acetone, methanol, ethanol, toluene, and isopropyl alcohol. Furthermore, to evaluate the feasibility of the modified PBI OSN membranes, ecamsule, a chemical product in the fine chemical industry, was recovered. Correspondingly, the efficient recovery of ecamsule from a toluene/methanol solution using the OSN process with PBI/MeCN membranes demonstrated their applicability in many fine chemical industries.

Solubility Models for the Recovery of Rosmarinic Acid from Orthosiphon Aristatus Extract Using Solid Phase Extraction

Hildebrand and Hansen solubility parameters, and log P value are widely used to determine the solubility of polymers in solvents. The models were used to explain the recovery of phytochemical, rosmarinic acid from Orthosiphon aristatus extract in C18 solid phase extraction (SPE) using the eluent consisting of ethyl acetate and chloroform in the decreasing polarity of solvent system. The experimental recovery of rosmarinic acid appeared to be well explained by the Hansen solubility model. The small difference in the Hansen solubility parameters, particularly for dispersion and hydrogen bonding forces, results in a higher polar solvent system for high rosmarinic acid recovery. The results found that the Hansen solubility model fitted well to the recovery of rosmarinic acid from crude extract with high coefficient of determination (R2 > 0.8), low standard error (4.4%), and p < 0.05. Hildebrand solubility is likely to be the second fit model, whereas log P has poor R2 < 0.7 and higher standard error (7.3%). The Hansen solubility model describes the interaction of solute–solvent in three dimensions (dispersion, polar, and hydrogen bonding forces) which can accurately explain the recovery of rosmarinic acid. Therefore, Hansen solubility can be used to predict the recovery of rosmarinic acid from O. aristatus extract using SPE.

Influence of Solvent Selection in the Electrospraying Process of Polycaprolactone

Electrosprayed polycaprolactone (PCL) microparticles are widely used in medical tissueengineering, drug control release delivery, and food packaging due to their prominent structuresand properties. In electrospraying, the selection of a suitable solvent system as the carrier of PCL isfundamental and a prerequisite for the stabilization of electrospraying, and the control ofmorphology and structure of electrosprayed particles. The latter is not only critical for diversifyingthe characteristics of electrosprayed particles and achieving improvement in their properties, butalso promotes the efficiency of the process and deepens the applications of electrosprayed particlesin various fields. In order to make it systematic and more accessible, this review mainly concludesthe effects of different solution properties on the operating parameters in electrospraying on theformation of Taylor cone and the final structure as well as the morphology. Meanwhile,correlations between operating parameters and electrospraying stages are summarized as well.Finally, this review provides detailed guidance on the selection of a suitable solvent systemregarding the desired morphology, structure, and applications of PCL particles.

Ranking and similarity of conventional, microwave and ultrasound element sequential extraction methods

This study aims to compare three extraction techniques of four sequential element extraction steps from soil and sediment samples that were taken from the location of the Pančevo petrochemical industry (Serbia). Elements were extracted using three different techniques: conventional, microwave and ultrasound extraction. A novel procedure - sum of the ranking differences (SRD) - was able to rank the techniques and elements, to see whether this method is a suitable tool to reveal the similarities and dissimilarities in element extraction techniques, provided that a proper ranking reference is available. The concentrations of the following elements Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Si, Sn, Sr, V and Zn were determined through ICP OES. The different efficiencies and recovery values of element concentrations using each of the three extraction techniques were examined by the CRM BCR-701. By using SRD, we obtained a better separation between the different extraction techniques and steps when we rank their differences among the samples while lower separation was obtained according to analysed elements. Appling this method for ordering the elements could be useful for three purposes: (i) to find possible associations among the elements; (ii) to find possible elements that have outlier concentrations or (iii) detect differences in geochemical origin or behaviour of elements. Cross-validation of the SRD values in combination with cluster and principal component analysis revealed the same groups of extraction steps and techniques.

Evaluation of reversed-phase nano liquid chromatography conditions by using reversed-phase thin layer chromatography based on Hansen solubility parameters for the analysis of amphiphilic glycosylsphingolipid transformations

Pulse chase analysis is often used in investigating dynamics of cellular substances. Fluorescently labeled lactosyl sphingosine molecule is useful in chasing its transformation, however the analysis of such metabolites in attomole level is of extreme difficult due to the presence of large amount of endogenous amphiphilic molecules such as glycosphingolipids, sphingomyerin, and glycerophospholipids. Nano LC suites for analyzing the attomole scale metabolites, therefore removal of endogenous substances prior to nano LC and finding appropriate nano LC conditions are necessary. Thus, we focused on the solubility of fluorescent BODIPY-labeled lactosylsphingosine (Lac-Sph-BODIPY) to identify suitable solvents to remove endogenous compounds. In this study, we evaluated solvents by using C18 thin layer chromatography (RP TLC). The mobility (R_f) of Lac-Sph-BODIPY against several solvent mixtures on RP TLC were plotted against polarity and hydrogen bonding capability followed by Hansen solubility parameters (HSPs). The optimum solvent mixture with R_f = 0.3 ± 0.1 was chosen for elimination of endogenous phospholipids on a ZrO₂-SiO₂ cartridge column and subsequent separation by nano LC. Efficient removal of endogenous phospholipids was demonstrated, and good resolution in nano LC analysis of Lac-Sph-BODIPY extracted from Chinese hamster ovary (CHO)-K1 cells was achieved. It was also shown that the amount of exogenously added compound was important in the investigation of metabolites using cultured cells.