Polyethylene glycol precipitation

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Recovery of serine protease inhibitor from fish roes by polyethylene glycol precipitation

Recovery of serine protease inhibitor from fish roes by polyethylene glycol precipitation

Polyethylene glycol-4000 (PEG4000), which is a chemical used for fractionation, was obtained from the Yakuri Pure Chemicals Co., Ltd. (Kyoto, Japan). Trypsin, chymotrypsin, bromelain, and papain were from Sigma-Aldrich Chemical Co. (St. Louis, MO, USA). Alcalase 2.5 type DX, Neutrase 0.8 L, Flavourzyme 500 MG, and Protamex were purchased from Novozymes (Bagsvaerd, Denmark). Aroase AP-10 and Pancidase NP-2 were from Yakult Pharmaceutical Co., Ltd. (Tokyo, Japan). Protease-NP was purchased from Amore- pacific Co., Ltd. (Seoul, Korea). Casein and N α -benzoyl- DL-arginine-2-naphthylamide hydrochloride (BANA) as substrates were purchased from Sigma-Aldrich Chemical Co. (St. Louis, MO, USA). The buffer solutions (0.1 M sodium phosphate buffer, pH 6.0; 0.1 M Tris-HCl buffer, pH 9.0) for enzyme reaction were prepared according to the method of Dawson et al. (1986). Sodium dodecyl sulfate (SDS) and glycine were purchased from Bio Basic Inc. (Ontario, Canada). Coomassie brilliant blue R-250 was purchased from Bio-Rad Laboratories, Inc. (Hercules, CA, USA). Glycerol and β -mercaptoethanol were pur- chased from Sigma-Aldrich Chemical Co. (St. Louis, MO, USA). Bromophenol blue was purchased from Junsei Chemical Co., Ltd. (Tokyo, Japan).
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Identification of bacterial antigens in circulating immune complexes of infective endocarditis

Identification of bacterial antigens in circulating immune complexes of infective endocarditis

The presence of circulating immune complexes (IC) in patients with infective endocarditis has been well documented but the contributions of host and bacterial components to these IC have not been defined. To study this question, IC were isolated from serum of a patient with Streptococcus faecalis endocarditis by differential polyethylene glycol precipitation and competitive binding to staphylococcal protein A. A rabbit antiserum raised against the

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Incorporation of a Proteotyping Approach Using Mass Spectrometry for Surveillance of Influenza Virus in Cell Cultured Strains

Incorporation of a Proteotyping Approach Using Mass Spectrometry for Surveillance of Influenza Virus in Cell Cultured Strains

The reemergence of deadly pandemic influenza virus strains has necessitated the development of improved methods for rapid detection and subtyping of influenza viruses that will enable more strains to be characterized at the molecular level. Representa- tive circulating strains of human influenza viruses from primary clinical specimens were grown in cell culture, purified through polyethylene glycol precipitation, proteolytically digested with an endoproteinase, and analyzed and identified by high-resolu- tion mass spectrometry using unique signature peptides that are characteristic of type A H1N1 and H3N2 and type B influenza viruses. This proteotyping approach enabled circulating strains of type A influenza virus to be typed and subtyped, cocirculating seasonal and pandemic H1N1 viruses to be differentiated, and the lineage of type B viruses to be determined through single-ion detection by high-resolution mass spectrometry. Results were obtained using virus titers comparable to those used in reverse transcription (RT)-PCR assays with clinical specimens grown in cell cultures. The methodology represents a more rapid and di- rect approach than RT-PCR and can be integrated into existing procedures currently used for the surveillance of emerging pan- demic and seasonal influenza viruses.
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Promoieties Used In Prodrug Design: A Review

Promoieties Used In Prodrug Design: A Review

Polyethylene glycols (PEGs) appear to be particularly convenient as oligomeric matrices, since they are eas- ily available in wide range of well definite molecular weights. PEGs are well known to be non toxic, non antigenic and biocompatible. Given these properties, it is fantastic for use as a drug carrier as it is also rapidly eliminated from body. 3

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Characterization of Carbon Dots Covered with Polyvinylpyrrolidone and Polyethylene Glycol

Characterization of Carbon Dots Covered with Polyvinylpyrrolidone and Polyethylene Glycol

We adopted procedure to synthesize water soluble C-dots from Wang et al. and did slight modifications using ethylene glycol as solvent instead of glycerol [34]. Performed experiments were carried out parallel with two water soluble C-dots covered by different polymeric materials – PEG and PVP. Due to the fact that quantum dots and C-dots possess unique optoelectronic properties, at first spectrophotometric and fluorescence characterization was performed. The absorption spectra showed local absorption maxima app. 300 nm in the case of C-dots-PEG (Fig. 1Ab), but very weak absorption in this region in the case of C-dots-PVP (Fig. 1Aa). The absorption peak app. 300 nm was previously observed in the case of C-dots [24,35]. Different excitation wavelengths were used for excitation of C- dots complex with polymeric surface agents and the emission was found to be the strongest after excitation at 250 nm (Fig. 1B). Sharp decreases of fluorescence were observed in the case of excitation wavelength 310 nm. We suggest that the emissions after excitation at wavelengths higher than 310 nm are caused especially by aggregated polymers C-dots complex, but after filtration and centrifugation of samples obtained by synthesis, emission at these wavelengths significantly decreased (not shown). In further experiments the separated samples were used. Fluorescent microscope was used to visualize the micro-sized particles presented within sample and the particles of size app. 25 µm were observed (Figs. 1C and D). In order to elucidate the presence of fluorescent C-dots within samples, the fluorescence spectra of 1 % w/v capping polymers was compared with C-dots samples. PVP is weakly fluorescent polymer and as it can be seen in Fig. 1E and reaches fluorescence emission maxima at 305 nm. Nevertheless C-dots-PVP maxima are shifted to 360 nm (Fig. 1Ea). Dynamic light scattering measurements revealed the C-dots-PVP particles size 9 ± 3 nm (33 % of particles of 9 nm), as it is shown in Fig. 1F. Wang et al. mentioned that heated PEG in glycerol produces no fluorescent species [34]. We observed weak fluorescence of 1 % w/v PEG dissolved in water at 336 nm, but compared with emission maxima of C-dots-PEG at 384 nm it represents only 3.3 % (Fig. 1G). The size distribution of C-dots-PEG particles was determined from 2 to 6 nm with 27 % of particles of 3 nm size (Fig. 1H).
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DESIGNING AND CHARACTERIZATION OF DRUG FREE PATCHES FOR TRANSDERMAL APPLICATION

DESIGNING AND CHARACTERIZATION OF DRUG FREE PATCHES FOR TRANSDERMAL APPLICATION

The present investigation was taken up to prepare and evaluate drug free polymeric patches using different polymers and to study the effect of different plasticizers on physicochemical properties of the patches to explore their feasibility for transdermal application. Polyethylene glycol (PEG 400), Dibutylphthalate (DBP) and Propylene glycol (PG) were used as plasticizers at a concentration of 40 % w/w of dry polymer weight. Drug free polymeric patches were prepared by the casting method on mercury surface and evaluated for weight variation, thickness, flatness, tensile strength, folding endurance, surface pH, hardness, swellability, water vapour transmission rate and skin irritation studies. The mercury substrate method was found to give thin uniform patches.
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A Randomized, Prospective, Comparison Study of Polyethylene Glycol 3350 Without Electrolytes and Milk of Magnesia for Children With Constipation and Fecal Incontinence

A Randomized, Prospective, Comparison Study of Polyethylene Glycol 3350 Without Electrolytes and Milk of Magnesia for Children With Constipation and Fecal Incontinence

RESULTS. Thirty-nine children were assigned randomly to receive polyethylene gly- col and 40 to receive milk of magnesia. At each follow-up visit, significant im- provement was seen in both groups, with significant increases in the frequency of bowel movements, decreases in the frequency of incontinence episodes, and resolution of abdominal pain. Compliance rates were 95% for polyethylene glycol and 65% for milk of magnesia. After 12 months, 62% of polyethylene glycol- treated children and 43% of milk of magnesia-treated children exhibited improve- ment, and 33% of polyethylene glycol-treated children and 23% of milk of magnesia-treated children had recovered. Polyethylene glycol and milk of mag- nesia did not cause clinically significant side effects or blood abnormalities, except that 1 child was allergic to polyethylene glycol.
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Development of Transdermal Delivery System of Dexamethasone, Palonosetron and Aprepitant for Combination Antiemetic Therapy

Development of Transdermal Delivery System of Dexamethasone, Palonosetron and Aprepitant for Combination Antiemetic Therapy

the high molecular weight and required an additional enhancement approach to improve the permeation. In general, the permeation data observed with all the three drugs were in agreement with the drug release studies. Based on the above data, in all the three cases the flux values were maximum when the drug concentration was highest (1.5% w/w) and hence used for further studies. The role of skin permeation enhancers in improving the percutaneous absorption of therapeutic actives is well known. Hence, next phase of study assess the potential of chemical permeation enhancers to improve the flux of all three drugs. Four renowned permeation enhancers such as oleic acid, n-methyl-2-pyrrolidone, propylene glycol and polyethylene glycol 400 were selected based on the literature. 23,26 The concentration
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FORMULATION AND EVALUATION OF TOPICAL MICROEMULGEL LOADED WITH TERBINAFINE HCL MICROEMULSION

FORMULATION AND EVALUATION OF TOPICAL MICROEMULGEL LOADED WITH TERBINAFINE HCL MICROEMULSION

Screening of Excipients by Solubility Studies: Different oils including oleic acid, liquid paraffin, propylene glycol and various surfactants like tween 80 and tween 20 were screened for solubility studies. Excess amount of drug was added to different oils and surfactants. The mixture was continuously stirred in Rotary Shaker for 72 hour at room temperature and was subjected to centrifugation at 1000 rpm for 15 minutes. Supernatant liquid was decanted off and subjected to filtration using membrane filter. 1ml of filtrate was withdrawn and diluted with methanol to 1000 ml. The diluted samples were observed at 283 nm in UV-Vis spectrophotometer. The concentration of sample soluble in different oil and surfactant was measured comparing with standard calibration curve of Terbinafine HCL in methanol.
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ENHANCEMENT OF SOLUBILITY AND DISSOLUTION RATE OF EFAVIRENZ USING LIQUI SOLID COMPACT TECHNIQUE

ENHANCEMENT OF SOLUBILITY AND DISSOLUTION RATE OF EFAVIRENZ USING LIQUI SOLID COMPACT TECHNIQUE

The objective of the present investigation is to formulate Liqui-Solid tablets of Efavirenz. In the present study Efavirenz immediate release tablets were prepared by using aid of non-volatile solvents like polyethylene glycol (PEG) and propylene glycol (PG), in which the poorly soluble drug is dissolved and thereby increasing its solubility and in turn dissolution rate. The tablets were formulated using direct compression technology by employing super disintegrants like cross povidone and sodium starch glycolate. The prepared liquid-solid compact tablets were evaluated for pre compression, post compression and in-vitro drug release. The in-vitro drug release pattern of liqui- solid tablets of Efavirenz was fitted in kinetic model which showed highest regression i.e. for zero order kinetics. Among all the formulations, LS-12 which is a combination of Propylene glycol, Ratio (R) =2 and cross povidone- 4% was optimized based on desired immediate release time (10mins) followed by acceptable disintegration and drug release properties.
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One-day oral polyethylene glycol based cleanout is effective for pre-colonoscopy preparation in children

One-day oral polyethylene glycol based cleanout is effective for pre-colonoscopy preparation in children

glycol solution plus stimulant laxatives versus standard volume polyethylene glycol solution: a prospective, randomized study of colon cleansing before colonoscopy. Landreneau SW, Palma [r]

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Effects of polyethylene glycol as alternative activator in a bamboo fibre filled natural rubber composite.

Effects of polyethylene glycol as alternative activator in a bamboo fibre filled natural rubber composite.

From the above scenario, there is an interest from the research community to partially substitute or totally replace conventional zinc oxide with other material. Our effort here is also in that direction by trying to look at the effects of polyethylene glycol as alternative activator in a bamboo fibre filled natural rubber composite.

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Study of Intermolecular Interaction in Risperidone and Polyethylene Glycol Suspension

Study of Intermolecular Interaction in Risperidone and Polyethylene Glycol Suspension

Risperidone was obtained as gift sample from Ipca Laboratories Ltd. Sejavta, Ratlam. Polymer used is Polyethylene Glycol. All other chemicals and solvent were of analytical grades. Effect of drug-polymer ratio in internal phase on microparticles formulation was studied. Five different ratios of drug to polymer were employed to determine the effect of drug-polymer ratio on physical characteristics. In each formulation the amount of drug was kept constant at 0.5 gm and amount of polymer were changed.

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Preparation of flocculant for optimizing glycol lignin manufacturing process by cationization of glycol lignin

Preparation of flocculant for optimizing glycol lignin manufacturing process by cationization of glycol lignin

To utilize lignin, separation treatments, such as pulping procedures, are required for lignocellulosic materials. Lignin is connected to polysaccharides through the lignin–carbo- hydrate complex linkage. The chemical structure of the obtained lignin (technical lignin) is affected in various degrees by the chemical reactions during the separation from lignocellulose; thus, the chemical structure and properties of technical lignins are dependent on reaction conditions. For example, lignin is depolymerized to fragments during Kraft pulping with large chemical changes. Lignosulfonate obtained by sulfite pulping includes sulfonate groups, which contribute to its properties as a polyelectrolyte [2]. Kubo et al. reported the solvolysis of wood meal using carbon- ate/ethylene glycol with H 2 SO 4 at 150 °C. The polysaccha-
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Aqueous Solubility Enhancement of Mirtazapine: Effect of Cosolvent and Surfactant

Aqueous Solubility Enhancement of Mirtazapine: Effect of Cosolvent and Surfactant

Propylene glycol Propylene glycol 400 Polysorbate 20 Polysorbate 80 Sodium lauryl sulfate 0.00 0.00186 ± 0.0012 0.00186 ± 0.0012 0.00 0.00186 ± 0.0012 0.00186 ± 0.0012 0.00186 ± 0.0012 5.00 0.01087 ± 0.0011 0.01323 ± 0.0007 0.05 0.00743 ± 0.0005 0.01069 ± 0.0011 0.01293 ± 0.0006 10.0 0.01674 ± 0.0006 0.02082 ± 0.0016 0.10 0.01302 ± 0.0006 0.01653 ± 0.0013 0.02114 ± 0.0012 15.0 0.02003 ± 0.0008 0.02448 ± 0.0013 0.20 0.01562 ± 0.0007 0.02072 ± 0.0011 0.02521 ± 0.0004 20.0 0.02331 ± 0.0004 0.02813 ± 0.0008 0.50 0.02046 ± 0.0009 0.02678 ± 0.0006 0.03441 ± 0.0006 25.0 0.02663 ± 0.0012 0.03179 ± 0.0019 1.00 0.03088 ± 0.0012 0.04222 ± 0.0017 0.05089 ± 0.0011 30.0 0.03151 ± 0.0009 0.03781 ± 0.0012 2.00 0.05172 ± 0.0018 0.07142 ± 0.0013 0.08251 ± 0.0016 50.0 0.05115 ± 0.0008 0.06187 ± 0.0017
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Synthesis of nanostructured hydroxyapatite in presence of polyethylene glycol 1000

Synthesis of nanostructured hydroxyapatite in presence of polyethylene glycol 1000

The bands at 3572 and 632 cm -1 belong to the vibration of hydroxyl (O–H) group, the bands at 1089, 1045 and 962 cm -1 are the characterization of phosphate stretching vibration and the bands observed at 601, 570 cm -1 are due to the phosphate being in vibration. From the IR analysis, the precipitated powders are proved to be hydroxyapatite in nature. The presence of polyethylene glycol in hydroxyapatite does not play any role in the structural deformation of hydroxyapatite, meaning that HAp crystallites were prepared.

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Severe Poisoning After Accidental Pediatric Ingestion of Glycol Ethers

Severe Poisoning After Accidental Pediatric Ingestion of Glycol Ethers

Later that night, 8 hours after ingestion, the patient received hemodialysis for 3 hours. Dialysis bath consisted of 3 mEq/ L potassium, 35 mEq/L bicarbonate, and 140 mEq/L sodium. Follow-up labora- tory results revealed resolution of the acidosis, a fall in serum urea nitrogen, creatinine, and osmolality (Table 1). The dopamine infusion was quickly weaned off shortly after dialysis; he was extu- bated the following day and discharged from the hospital on day 3 in normal health. Serum concentrations (mea- sured on samples from presentation) of isopropanol, methanol, and ethylene glycol were undetectable, and serum propylene glycol was 9 mg/dL.
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Preparation and Fire Test of Intumescent Powder Coatings

Preparation and Fire Test of Intumescent Powder Coatings

In order to obtain a general view over the whole scope of intumescent powder coatings, seven recipies are de- veloped: two formulations based on thermoplastic binders, namely plastisized polyvinylchloride PPVC and polypropylene PP comprising bicyclopentaerythritol phosphate as intumescent ingredient. PPVC is chosen for char formation and low combustion. PP is selected, because it can be degraded to well flowing low molecular products by the addition of peroxides. Five non-cross linked thermosets comprising uretdione and linear polyes- ters as well as polyethylene glycol react to polyurethanes. Bicyclopentaerythritol phosphate is added as intu- mescent ingredient in the cases, when the binders show no intumescence by themselves. Use is made of the in- tumescent phosphororganic polyesters as binding component as well as intumescent mixtures of polyethylene glycol and ammonium polyphosphate. Polyurethanes are very familiar in powder coatings, for instance, Vest- agon from Evonik and Crelan from Bayer are well known commercial products.
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Physiological targets of salicylic acid on Artemisia aucheri BOISS as a medicinal and aromatic plant grown under in vitro drought stress

Physiological targets of salicylic acid on Artemisia aucheri BOISS as a medicinal and aromatic plant grown under in vitro drought stress

Artemisia aucheri BOISS is a medicinal and aromatic plant belongs to Asteraceae family. There are around 500 species of Artemisia in Asia, Europe and North Amer- ica and 34 species of this family are found all over Iran (Mozaffarian 2010). Artemisia aucheri is limited mostly to mountainous landscapes with high slope, sandy soils and with annual precipitation of 300–450 mm (Hosseini et al. 2013). Morphological features of this plant consist of perennial, suffrutescent, stem numerous and erect, indumentum white-tomentose, leaves pinnate or bipin- nate, capitula arranged in a panicle-congested, calathium sessile and ovate, phyllaries imbricate and multiseriate,
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Shape-, size- and structure-controlled synthesis and biocompatibility of iron oxide nanoparticles for magnetic theranostics

Shape-, size- and structure-controlled synthesis and biocompatibility of iron oxide nanoparticles for magnetic theranostics

the CCK-8 assay results revealed that more than 90% of cells survived, which suggested that these nanoparticles were quite safe to the cells within the tested concentration range. Spherical, hexagonal and wire-like shaped IONPs that were coated with carboxyl-terminated poly(ethylene glycol)-phospho- lipid (DSPE-PEG) for enhanced dispersion in water were tested in ECA-109 cells and the results showed that such nanoparticles were uptaken by cancer cells, and the particles induced negligible toxicity to the cells without laser irradiation. Upon laser irradiation, the cell structures were seriously damaged by the photothermal effects induced by the nanoparticles [67]. The cytotoxicity of magnetite nanorings (NRs) with high luminescence and a magnetic vortex core capped with quantum dots (QDs) was tested on normal human lung fibroblast cells (NHLF), MGH bladder cancer cells, and SKBR3 breast cancer cells. The results of a viability assay showed that after 24 h incubation with QD-FVIOs (ferrimagnetic vortex-state iron oxide nanorings) at 37 °C, both QD-FVIO1
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