Influence Of Organic Solvents Research Articles

Pharmaceutical nanonization by green supercritical processing: Investigation of Exemestane anti-estrogenic medicine solubility using machine learning

Oral administration is known as the most prevalently-employed approach of drug delivery because of possessing different benefits like simplicity of use, affordability and negligible sterility restrictions. Despite the noteworthy interests of scientists to manufacture oral therapeutic medicines, poor solubility/bioavailability of orally-administered drugs remains a big challenge in recent years. Therefore, various scientists are trying to develop novel techniques to enhance the solubility of orally-administered therapeutic agents. One of the promising ways, which has recently attracted the global attentions is the use of supercritical fluids (SCFs). This technique could overcome the unfavorable/detrimental influences of organic solvents on the environment due to its environmentally-benign characteristics, non-inflammability and low toxicity. In this research, the solubility of Exemestane (EXE) drug is modeled based on two parameters of temperature and pressure. In order to handle the modeling process, the AdaBoost method with three core models of linear regression (LR), K-Nearest Neighbor (KNN) and Gaussian Process (GPR) are considered, which are tuned by AEO method in terms of their hyper-parameters. Based on the evaluations carried out in this research, ADA GPR, ADA KNN, and ADA LR models showed 0.996, 0.991, and 0.925 values in terms of R-square score. Also, in terms of the error rate, the three models ADA GPR, ADA KNN, and ADA LR have an RMSE error equal to 1.3459, 1.8967, and 5.8875, respectively. Based on these facts and some other analyses, the Gaussian process model optimized and boosted with AdaBoost can be accepted as the most accurate model of this research.

Influence of Solvents and Solvent Mixtures on the Content of Polyphenols and Antioxidant Activity of Capsella bursa-pastoris (L.) Medik. Extracts

Capsella bursa-pastoris (L.) Medik. (known as shepherd's purse) is a plant whose parts are used as medicine in herbal medicine. It is applicable as a medicine in the treatment of all forms of internal bleeding, for the treatment of hemorrhoids, excessive menstruation, but also for the usual stopping of nosebleeds. Through this research, the influence of organic solvents and their aqueous mixtures on the efficiency of polyphenol extraction and antioxidant activity was compared. The inhibition of free radicals was tested by the DPPH method, while the FRAP method was used to test the reduction potential. Analyzes have shown that water is the most effective solvent in the isolation of polyphenols from the aerial parts of shepherd's purse. Mixtures of organic solvents with water also showed high efficiency in the extraction of bioactive components, while the weakest results were obtained for extracts prepared in pure organic solvents.

Features of anemia syndrome in women with endometrial hyperplasia working under the influence of organic solvents and depending on obesity

Introduction. Organic solvents have a hematotoxic effect, which leads to the development of anemia. Endometrial hyperplasia may also be the cause of a decrease in blood hemoglobin levels. The phenotype of anemia in combination of these diseases is still insufficiently studied. Exposure to organic solvents is associated with a carcinogenic risk, while their role in the development of precancerous conditions is little known.
 The study aims to research the features of anemia in patients with endometrial hyperplasia under the influence of organic solvents and depending on the obesity factor.
 Materials and methods. The design of the study is a single–center, single-stage observational. The researchers formed 2 groups of women with endometrial hyperplasia confirmed by histological examination, who worked under conditions of exposure to organic solvents (n=140, the main group, 70 of them obese according to WHO criteria) or who had no health risks (n=140, the comparison group, 68 of them obese). The patients of the main group are painters at a machine-building enterprise. Organic solvents concentrations at the workplace air were 1.2–5.0 times above occupational exposure limits, length of service was 21.5 (18; 28) years.
 Results. Scientists have registered anemia in 72.9% of obese workers, 54.2% of non-obese workers, 33.8% and 25.0% of patients in the comparison group with obesity and normal body weight, respectively, χ2=8.2, p=0.008. In contact with organic solvents, 60.7% of patients had anemia normal- or macrocytic, normal- or hyperchromic, hyporegenerative. In the subgroup of obesity and atypical endometrial hyperplasia, we have watched the minimum values of hemoglobin — 95 (90; 105) g/l and reticulocytes — 1 (0.5; 2), the maximum values of the average erythrocyte volume — 98 (92; 107) fl and the average hemoglobin content in the erythrocyte — 35(34; 38) pg. The researchers have determined the association of this variant of anemia with atypical endometrial hyperplasia by logistic regression, OR 2.51, 95% CI 1.08–5.85, p=0.033. In comparison group, all patients had iron-deficiency anemia.
 Limitations. The limitations of the study are related to the recruitment of patients in one center.
 Conclusion. Anemia in women with endometrial hyperplasia in conditions of organic solvents exposure is normo- or hyperchormic, normo- or macrocytic, hyporegenerative, most prominent in patients with obesity, and associated with atypical histological type of the disease.
 Ethics. The authors have carried out the study in compliance with the Ethical principles of conducting scientific medical research with human participation, set out in the Helsinki Declaration of the World Medical Association and in accordance with the Ethical norms and rules provided for by the Bulletin of the Higher Attestation Commission of the Ministry of Education of Russia No. 3 of 2002 "On the procedure for conducting biomedical research in humans". The study was approved by the Ethics Committee of the Federal State Budgetary Educational Institution of the Russian Ministry of Health.

Effects of Typical Solvents on the Structural Integrity and Properties of Activated Kaolinite by Wet Ball Milling.

The influence of organic solvents on the structural integrity and properties of activated kaolinite were compared and analyzed via characterization techniques and molecular dynamics (MD) simulation. The results revealed that the organic intercalators can be easily inserted into the interlayer spaces of activated kaolinite within a short time of the wet ball milling. The DMSO intercalated kaolinites maintained structural integrity due to the high intercalation rate and the excellent buffering effect against the crushing force of milling during the delamination/exfoliation process. The delaminated layers of the DMSO-kaolinite complex exhibited a high specific surface area of 99.12 m2/g and a low average thickness of 35.21 nm. The calculated elastic properties of the organo-kaolinite complex manifested the intercalation of DMSO into a kaolinite interlayer, which could improve the compressibility and structural integrity of kaolinite nanosheets. The DMSO-kaolinite complex was easier to peel off when compared to the other organic intercalators due to its more intercalated molecules.

Damaging effect of admixtures used in crop protection products on high density polyethylene packaging material

The phenomenon of environmental stress cracking is still a major issue in materials engineering as well as from a scientific perspective. Especially in the case of packaging materials made of high-density polyethylene, assessing the potential of premature damage due to environmental stress cracking is complex because of the large number of components in possible liquid filling goods. As a first guideline, the well-known effect of detergents and dispersants is usually considered, but the interplay with other components, such as organic solvents is often unknown. Particularly challenging in this respect are crop protection products, consisting of several different admixtures in addition to the biologically active ingredients. This study is based on two model liquids representing these admixtures that were established for testing in this context. The model liquids as well as their constituting components were used as liquid media in the Full Notch Creep Test to characterize the environmental stress cracking behavior of a typical high-density polyethylene. Complementary to the time-to failure of a notched specimen obtained from these tests, the crack opening was monitored optically, and the fracture surface was analyzed post-failure by laser scanning microscopy as well as scanning electron microscopy. Based on the results, the effect of various surfactants as well as the influence of organic solvents on environmental stress cracking are discussed.

Organic solvent extraction and spectrophotometric quantification of total phenolic content of soil

Phenolic compounds are regarded as the most abundant plant metabolites that are known to decompose progressively into soils, likened to other soil organic materials. Once assimilated into soils, they can control soil processes, including organic matter decomposition and nutrient cycling. Established that phenolic compounds can influence nutrients availability and soil quality, it becomes crucial to investigate into soil phenolics through the application of appropriate extraction technique and quantification of ​total phenolic content ​in soils. This study therefore aimed at utilizing ethanol, hexane and diethyl ether organic solvents to extract and quantify total phenolic content of soil, sampled from a vegetable growing area. Conventional organic solvent extraction method was employed to extract phenolics, while spectrophotometric technique was utilized to quantify total phenolic content. The highest extraction yield of 34.52% was achieved with ethanol followed by diethyl ether (28.23%) and hexane (25.47%). Interestingly, hexane, which had the least extraction yield, rather recorded the highest phenolics concentration of 5.50 ± 0.02 mgGAE/g, with ethanol producing a concentration of 2.04 ± 0.05 mgGAE/g and 3.82 ± 0.01 mgGAE/g for diethyl ether. The percent recovery, limit of detection (LOD) and limit of quantification (LOQ) of phenolic compounds were found to be 102%, 0.8 mg/g and 1.5 mg/g for ethanol; 96%, 0.6 mg/g and 1.2 mg/g for diethyl ether and 94%, 0.4 mg/g and 1.0 mg/g for hexane respectively. These results indicate that for an extraction efficiency and greater yield, the use of ethanol as solvent is preferred whereas extraction using hexane is suitable for total phenolics quantification. The findings of this study have provided a vital insight regarding the influence of organic solvents on the extractability and quantification of total phenolic content of soil.

Electrochemical DNA Sensor Based on Poly(Azure A) Obtained from the Buffer Saturated with Chloroform.

Electropolymerized redox polymers offer broad opportunities in detection of biospecific interactions of DNA. In this work, Azure A was electrochemically polymerized by multiple cycling of the potential in phosphate buffer saturated with chloroform and applied for discrimination of the DNA damage. The influence of organic solvent on electrochemical properties of the coating was quantified and conditions for implementation of DNA in the growing polymer film were assessed using cyclic voltammetry, quartz crystal microbalance, and electrochemical impedance spectroscopy. As shown, both chloroform and DNA affected the morphology of the polymer surface and electropolymerization efficiency. The electrochemical DNA sensor developed made it possible to distinguish native and thermally and chemically damaged DNA by changes in the charge transfer resistance and capacitance.

Organic Solvent Extraction and Spectrophotometric Quantification of Total Phenolic Compounds in Soil

Phenolic compounds are regarded as the most abundant plant metabolites that are known to decompose progressively into soils likened to other soil organic materials. Once assimilated into soils, they can control soil processes, including organic matter decomposition and nutrient cycling. Established that phenolic compounds can influence nutrients availability and soil quality, its crucial to investigate into soil phenolics through the application of the appropriate extraction technique and quantification of total phenolics in soils. This study therefore aimed at utilizing ethanol, hexane and diethyl ether organic solvents to extract and quantify total phenolic compounds in soil, sampled from vegetable growing area. Conventional organic solvent extraction method was employed to extract phenolics, while spectrophotometric technique was utilized to quantify total phenolic compounds. The highest extraction yield of 34.52% was achieved with ethanol followed by diethyl ether (28.23%) and then hexane (25.47%). Interestingly, hexane, which had the least extract yield rather recorded the highest phenolics concentration of 5.50 ± 0.02 mgGAE/g, with ethanol extract producing the least phenolics concentration of 2.04 ± 0.05 mgGAE/g. These results indicate that for an extraction efficiency and greater yield, the use of ethanol as an extraction solvent is preferred whereas extraction using hexane is suitable for total phenolics quantification. The findings of this study have provided a vital information regarding the influence of organic solvents on the extractability of phenolic compounds from soil.

Enhanced Nanostructured ZnO-Based Photocatalyst Immobilized by Ink-Jet Printing for Methylene Blue Degradation

Exploring facile fabrication methods for stable, ordered-structure photocatalysts with high performance is critical to realize their practical applications. In this work, a ZnO-based photocatalyst was deposited using a solution-processing ink-jet printing technique. Novel water-based inks were developed with pure ZnO and Mg-doped ZnO nanoparticles, which were synthesized by the polyacrylamide gel method and then modified by polyethylene glycol. The influence of organic solvents, surfactants, and polymers on the surface tension and viscosity of the inks was investigated using an orthogonal experimental design. The printed films annealed at low temperatures exhibited low resistance and high photocatalytic performance for the degradation of methylene blue. These results indicated that ink-jet printed Mg-doped ZnO photocatalyst thin film is promising as a feasible candidate for treating organic pollutants in waste water.

Influences of Organic Solvents on the Properties of 1-Butyl-3-methylimidazolium Acetate

Imidazolium-based ionic liquids (ILs) are widely studied in the biochemical process. In this work, because of the high viscosity of the IL, namely, 1-butyl-3-methylimidazolium acetate, the organic ...

Influence of organic solvents on rate of oxidization of sulfoxide by peroxy acids

The rate of the oxidation reaction of sulfoxides with peroxy acid in various organic solvents was studied. In this work we used dimethyl sulfoxide, dibutyl sulfoxide and diphenyl sulfoxide as substrate and peroxydecanoic, peroxybenzoic, peroxydodecanoic, and peroxypentanoic acids were taken as oxidant. The reaction mechanism involving the rapid formation of the sulfoxide-peroxyacid intermediate, which is decomposed during the second stage to form carboxylic acid and corresponding sulfone. The second stage is the rate-limiting step. It has been found the effective rate constants (k) and activation energy (E act ) for the studied process. Between the parameters of the transition state, ΔН ≠ and ΔЅ ≠ is a linear relationship indicating the presence of the compensative effect in all series of experiments. The reaction medium affects the rate of oxidation. Correlation equations between the rate constants of the reactions and the physicochemical parameters of the solvents were proposed. The correlation equation for effective rate constants and the basic physicochemical parameters of solvents at 318 K has the form: k = 17.1292 + (1027.5613 ±216.2400 )f(n) + (45.5329 ± 51.1522)f (ε) + + (0.1208 ± 0.0761)B – (3.2629 ± 1.2885)E T – (0.2047 ± 0.0913)δ 2 – (0.0605 ± 0.4335)V м , N =12; R=0,9800; S= 8.7942; F= 0.5715 The polarizability, basicity, electrophilicity and Hilderbrand's function of solvent affects the oxidation process. The influence of polarization and molar volume on the rate of oxidation of the sulfoxide decay process is negligible. Correlation equations for effective rate constants for other temperatures are similar. The proposed correlation equations relate the parameters of the transition state of the oxidation process and the physic-chemical parameters of solvents. Keywords: sulfoxides, peroxy acids, the influence of solvents, correlation equations.

Influence of Organic Solvents on Secondary Brain Damage after Experimental Traumatic Brain Injury.

Many compounds tested for a possible neuroprotective effect after traumatic brain injury (TBI) are not readily soluble and therefore organic solvents need to be used as a vehicle. It is, however, unclear whether these organic solvents have intrinsic pharmacological effects on secondary brain damage and may therefore interfere with experimental results. Thus, the aim of the current study was to evaluate the effect of four widely used organic solvents, dimethylsulfoxide (DMSO), Miglyol 812 (Miglyol®), polyethyleneglycol 40 (PEG 40), and N-2-methyl-pyrrolidone (NMP) on outcome after TBI in mice. A total of 143 male C57Bl/6 mice were subjected to controlled cortical impact (CCI). Contusion volume, brain edema formation, and neurological function were assessed 24 h after TBI. Test substances or saline were injected intraperitoneally (i.p.) 10 min before CCI. DMSO, Miglyol, and PEG 40 had no effect on post-traumatic contusion volume after CCI; NMP, however, significantly reduced contusion volume and brain edema formation at different concentrations. The use of DMSO, Miglyol, and PEG 40 is unproblematic for studies investigating neuroprotective treatment strategies as they do not influence post-traumatic brain damage. NMP seems to have an intrinsic neuroprotective effect that should be considered when using this agent in pharmacological experiments; further, a putative therapeutic effect of NMP needs to be elucidated in future studies.

Influence of Organic Solvents on Adhesive Wear of Titanium Slid against Ceramics

Influence of Organic Solvents on Adhesive Wear of Titanium Slid against Ceramics

Influence of organic solvents in the Pt nanoparticle synthesis on MWCNT for the methanol oxidation reaction

We studied the effect of the organic solvent on the synthesis of platinum nanoparticles anchored on the surface of multi-wall carbon nanotubes (Pt NPs/MWCNT) by the reverse microemulsion method. For oil phase, three organic solvents of the same alkane chain length (six carbon atoms) were tested: hexane, cyclohexane, and 2,2,4-trimethylpentane. The total metallic content was characterized by thermogravimetric analysis (TGA), and Pt NPs were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The chemical structure of the oil phase influences the Pt loading and crystallite size. The catalyst prepared with 2,2,4-trimethylpentane showed the highest electrochemical active surface area, enhancing the mass and specific activity compared to the commercial electrocatalyst (Pt/C) in the methanol oxidation reaction (MOR).

LC–ELISA as a contribution to the assessment of matrix effects with environmental water samples in an immunoassay for estrone (E1)

Estrone (E1), a metabolite of the estrogenic hormones 17β-estradiol (β-E2) and 17α-estradiol (α-E2), is itself a potent estrogen which can have a significant impact on the hormonal balance. Due to its high potential for adverse effects on human health and aquatic life even at pg/L to ng/L levels, its appearance in water should be monitored. E1 has also been considered a marker substance for the presence of other estrogens. This study presents a newly developed direct competitive enzyme-linked immunosorbent assay (ELISA) for quantification of E1 in environmental water samples using new monoclonal antibodies. The quantification range of the ELISA is 0.15 µg/L to 8.7 µg/L E1, and the limit of detection is around 60 ng/L for not pre-concentrated water samples. A pre-concentration step after careful selection of suitable phases for SPE was developed, too. The influence of organic solvents and natural organic matter on the ELISA was assessed. The high selectivity of the monoclonal antibody was demonstrated by determining the cross-reactivity against 20 structurally related compounds. For the assessment of matrix effects, a concept (“LC–ELISA”) is thoroughly exploited, i.e., separating complex samples by HPLC into 0.3 min fractions and determination of the apparent E1 concentration. Furthermore, fractions with interferences for nontarget/suspected-target analysis can be assigned. A dilution approach was applied to distinguish between specific interferences (cross-reactants) and non-specific interferences (matrix effects). In the determination of 18 environmental samples, a good agreement of the E1 concentration in the respective fractions was obtained with mean recoveries of 103 % to 132 % comparing ELISA to LC–MS/MS.

Influence of organic solvents on the furin activity

Influence of organic solvents on the furin activity

New Polyampholyte Polymers Based on Polypropylene Glycol Fumarate with Acrylic Acid and Dimethylaminoethyl Methacrylate

The possibility of preparing new polyampholyte polymers based on polypropylene glycol fumarate–acrylic acid–dimethylaminoethyl methacrylate terpolymers was demonstrated. The main relationships of radical terpolymerization in dioxane, including binary systems participating in the terpolymerization, were studied. The block lengths, transition probabilities, and Harwood block structure parameter were calculated for the terpolymers from the copolymerization constants for the binary systems. These parameters reflect the arrangement of the macroradicals in the chain. The morphology of the polymer surface was studied by scanning electron microscopy, and the surface pore size was estimated. The influence of organic solvents and pH on the sample swelling was studied, and the isoelectric point (pH 6.00) of the terpolymer was determined.

Solvatochromic effect in solutions of poly-ortho-toluidine

The influence of organic solvents (dimethylformamide, tetrahydrofuran, chloroform, nitrobenzene and toluene) on the spectral characteristics of solutions in doped and non-alloyed forms of poly-ortho-toluidine (PoTi) was studied. The absorption spectra of poly-ortho-toluidine, measured in solvents of different polarity, reveal a change not only the position, but also the intensity and shape of the absorption band, depending on the polarity of the solvent. It was noticed, that different forms of PoTi cause the difference in the coloration of their solutions. Based on the study of optical spectra, temperature dependence of conductivity and the structure of PoTi, it has been founded that this conjugated polymer can be a perspective basis for sensory environments for the molecular recognition of organic solvents. Keywords: poly-ortho-toluidine, solvatochromic effect, organic solvents, absorption spectra.

Doping effects of surface functionalization on graphene with aromatic molecule and organic solvents

Aromatic molecule functionalization plays a key role in the development of graphene field-effect transistors (G-FETs) for bio-detection. We have investigated the doping effects of surface functionalization and its influence on the carrier mobility of graphene. The aromatic molecule (1-pyrenebutanoic acid succinimidyl ester, PBASE), which is widely used as a linker to anchor bio-probes, was employed here to functionalize graphene. Dimethyl formamide (DMF) and methanol (CH3OH) were used as two solvents to dissolve PBASE. Raman spectra showed that both PBASE and these two solvents imposed doping effects on graphene. The PBASE was stably immobilized on the graphene surface, which was confirmed by the new peak at around 1623.5cm−1 and the disordered D peak at 1350cm−1. Electrical measurements and Fermi level shift analysis further revealed that PBASE imposes a p-doping effect while DMF and CH3OH impose an n-doping effect. More importantly, CH3OH causes a smaller reduction in the carrier mobility of G-FETs (from 1095.6cm2/Vs to 802.4cm2/Vs) than DMF (from 1640.4cm2/Vs to 5.0cm2/Vs). Therefore, CH3OH can be regarded as a better solvent for the PBASE functionalization. This careful study on the influence of organic solvents on graphene during PBASE functionalization process provides an effective approach to monitor the surface functionalization of graphene.

Влияние органических растворителей и кислот на гидратацию хитозана

Влияние органических растворителей и кислот на гидратацию хитозана