Extraction Procedure

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Quantification of individual phosphorus forms in surface sediments of the Southern Caspian Sea - Iranian Coast: A sequential extraction procedure

Quantification of individual phosphorus forms in surface sediments of the Southern Caspian Sea - Iranian Coast: A sequential extraction procedure

The top 5 cm of the surface sediment samples from 3 depths of 5, 10 and 20 m were collected from four different sites of Caspian Sea in autumn and winter 2013-2014. Samples were collected with a stainless steel grab sampler, placed in nylon bags, closed tightly and then kept in a refrigerator (4ºC) during shipping. Samples were stored at -20º C until further treatment. In order to characterize various P- species in the sediment, a sequential extraction procedure proposed by Psenner et al. (1984) was used (Fig. 2). The concentration of phosphorus was determined using UV–Vis Cecil1020 spectrophotometer technique. All samples were analyzed at maximum wavelength of 885 nm according to the molybdate blue method (Riley and Murphy, 1962).
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Elaboration of novel extraction procedure to reveal bioactive component profile of anthocyanin rich plants 

Elaboration of novel extraction procedure to reveal bioactive component profile of anthocyanin rich plants 

to the comparison of several sequential methods, the most suitable multiple extraction protocol may be suggested for possible food industrial applications. The novelty of the work is supported by the fact that such combinations of different extraction procedures have not been described previously, single-solvent extractions mainly prevailing in both the industrial and laboratory applications. The highest anthocya- nin content was found for sweet cherry using the sequential extraction procedure with the application of ethanol (sequential, single-solvent ethanol extrac- tion). The highest phenolic content, however, was assessed in the blackberry extracts obtained with methanolic extraction. DPPH antioxidant activity was found to be the highest in the case of sweet cherry using methanol as the extraction agent. The combined method has one more important advantage over the conventional ones: it does not require the use of elevated temperatures during the extraction process, which is beneficial for the heat sensitive natural compounds.
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Antibacterial And Phytochemical Screening Of Pimpinella Anisum Through Optimized Extraction Procedure

Antibacterial And Phytochemical Screening Of Pimpinella Anisum Through Optimized Extraction Procedure

Since synthetic drugs failed to work on microbial resistance we focused on antimicrobial properties of naturally occurring Pimpinella anisum, which may help in the search for newer and less expensive antibiotics. Antibacterial effects of ethanol and methanol extracts taken of second, fifth and seventh days, along with aqueous extracts of aniseed were observed on nine bacteria by disc diffusion method. Aniseed extracts of different days showed positive antibacterial effects on only three bacteria, named, Bacillus cereus, Bacillus subtilis and Streptococcus pneumonae. The methanol extract from the 5 th day showed the highest positive result against B. cereus whereas the zone of inhibition for B. subtilis was maximum for the 7 th day of ethanol extracts. Additionally, the aqueous extract of aniseed showed unremarkable result against S. pneumonae. Again, the activity index of methanol extract of day five was the highest against Bacillus subtilis indicating high sensitivity to the extract. The phytochemical analysis of the aqueous extract revealed the presence of alkaloids, flavonoids, saponins, tannins, terpenoids, phenolic compounds and cardiac glycosides. As extraction procedure is optimized through this examination, it is expected that the findings of this study will stimulate researchers to design clinical trials that may lead to the development of less expensive antimicrobial agents.
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Physicochemical Characteristics of Garlic (Allium sativum L.) Oil: Effect of Extraction Procedure

Physicochemical Characteristics of Garlic (Allium sativum L.) Oil: Effect of Extraction Procedure

Since, it has a high amount of unsaturated fatty acids, it is more prone to rancidity and needs to be prevented from oxidation. Thus, the oxidation deterioration of oil was measured by % FFA, acid value and peroxide value. Although, the peroxide value of GO (2%) was lower than that of other edible oils such as palm kernel oil (3.58%), but due to its high content of unsaturated fatty acids, it cannot be concluded that GO can be kept for a very long period of time [22]. In addition, the peroxide value changed according to the extraction procedure and it was less than 1% in SCF extraction in comparison with solvent and steam distillation method (Table 1). Therefore, it is observed that the SCF extraction with Co 2 has minor
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Frontal Facial Pose Recognition Using a Discriminant Splitting Feature Extraction Procedure

Frontal Facial Pose Recognition Using a Discriminant Splitting Feature Extraction Procedure

Frontal facial pose recognition deals with classifying facial images into two-classes: frontal and non-frontal. Recognition of frontal poses is required as a preprocess- ing step to face analysis algorithms ( e.g. face or facial expression recognition ) that can operate only on frontal views. A novel frontal facial pose recognition technique that is based on discriminant image splitting for feature extraction is presented in this paper. Spatially homoge- neous and discriminant regions for each facial class are produced. The classical image splitting technique is used in order to determine those regions. Thus, each facial class is characterized by a unique region pattern which consists of homogeneous and discriminant 2-D regions. The mean intensities of these regions are used as features for the classification task. The proposed method has been tested on data from the XM2VTS facial database with very satisfactory results.
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Thyristor Compact Modeling based on Gummel Poon Model Including Parameter Extraction Procedure

Thyristor Compact Modeling based on Gummel Poon Model Including Parameter Extraction Procedure

Recently, Sayah et al. [9] proposed a SPICE model based also on the Gummel-Poon model and taking conductivity modulation into account. The advantage of this work is that a full parameter extraction sequence is provided [10]. This modeling technique is chosen in this paper as a starting point for the model. Some effects are added by modeling the conductivity modulation of the base region including the carrier-carrier scattering which is important to accurately adjust the static characteristics. Also, a detailed study is provided to demonstarte the variation of the current gains of the two transistor components of the model with the injection level in order to provide an accurate identification of the SPICE parameters of the model. An extraction of the design parameters is provided based on some analytical expressions and a trimming of these parameters is done using measurements. Finally, a case study is taken and its design parameters are extracted. Static and dynamic behaviors using SPICE simulations are compared with measurements showing good agreement.
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Speciation of Trace Metals Pb, Zn, Cu and Cd in Surficial Sediment from Makupa Creek Mombasa, Coastal Kenya

Speciation of Trace Metals Pb, Zn, Cu and Cd in Surficial Sediment from Makupa Creek Mombasa, Coastal Kenya

Trace metals (Zn, Pb, Cu, Cd) speciation of surface sediments from Makupa creek, coastal Kenya were determined by sequential extraction procedure. The procedure was used to extract the trace metals in sediments geochemical phases (exchangeable, carbonates, Fe-Mn oxides, organic mat- ter/sulphide, and residual). Trace metals analysis was done using ICP/MS. The trace metal specia- tion results indicated that Pb, Zn, and Cd were mainly associated with the exchangeable, carbo- nates and Fe-Mn oxides in most of the sampling sites. The highest concentration of the trace met- als were associated with Fe-Mn oxides with Zn concentration at 362.5 µg/g, Pb, 31.5 µg/g. Copper was mostly associated with the organic matter/sulphide and carbonate at concentration of 117.5 µg/g and 69.9 µg/g respectively. Generally, trace metals in sediment from Makupa creek were mainly associated with the bioavailable fractions (BAF) and their ranges were: Pb (60% - 98%), Zn (90% - 99%), Cu (70% - 91%). It was found therefore, that there was trace metals enrichment in sediments from Makupa from anthropogenic sources and bioavailable to biota.
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Rapid HPLC Method for Monitoring Relevant Residues of Pharmaceuticals Products in Environmental Samples

Rapid HPLC Method for Monitoring Relevant Residues of Pharmaceuticals Products in Environmental Samples

Respect to the soil samples, the extraction procedure of analytes was optimized using a sample obtained by spiking 2 mg/L of the drugs studied over 0.5 g of soil Several extraction procedures using different solvents (acetone, methanol, water, 2-propanol, carbon tetrachlo- ride) at several percentages were essayed and the recov- eries them were calculated. The best results were ob- tained using a volume of 5 mL of methanol for the ex- traction of the analytes from the soil samples; this ex- periment was repeated three times.

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Isolation of species specific protein antigens of Rickettsia typhi and Rickettsia prowazekii for immunodiagnosis and immunoprophylaxis

Isolation of species specific protein antigens of Rickettsia typhi and Rickettsia prowazekii for immunodiagnosis and immunoprophylaxis

prowazekii by the selective Tris extraction procedure described here has several distinct advantages over the purification of SPAs by diethylaminoethyl cellulose chromatography from the [r]

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Separation and Quantification of Major Anti-Oxidant Compounds in Freeze Dried Samples of Punica granatum Juice by High Performance Liquid Chromatography

Separation and Quantification of Major Anti-Oxidant Compounds in Freeze Dried Samples of Punica granatum Juice by High Performance Liquid Chromatography

An increase in demand in the usage of pomegranate and its various products has been found worldwide in recent years mainly due to the high anti-oxidant properties. By considering this fact in mind a RP-HPLC method reported here represents; a simple, accurate and rapid technique for the simultaneous determination of four major marker constituent responsible for the anti-oxidant activity (vitamin C, gallic acid, ellagic acid and rutin). This was the first report on the simultaneous determination these 4 markers in freeze dried extract of pomegranate juice. The main advantage of the method includes the simplicity of extraction procedure, simultaneous detection and quantification of all the bioactive components in a single chromatographic run. The quantification limits were found to be low enough for the successful employment of the method in different products which contains these components even in very minute quantities The efficiency of the method was evaluated from conducting recovery experiments and the results found to be promising, which indicates that the method can be executed successively in various pomegranate products with high accuracy and precision. The linearity experiments conducted proved the method can be applied for the samples which contain these components in a wide range. In conclusion, the proposed method is useful as a reliable, fast and effective tool for the quality control as well as standardization of different value added products of pomegranate. This simple multi-component assay method can also be extended for the pharmacological, biopharmaceutical and pharmacokinetic studies.
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N-octyl-modified magnetite NPs for optimization of solid phase extraction for trace analysis of phenytoin in real samples

N-octyl-modified magnetite NPs for optimization of solid phase extraction for trace analysis of phenytoin in real samples

Objective: Phenytoin is an anti-seizure medication used to treat epilepsy, as well as to control arrhythmias and treat migraine headaches and nerve pain. It is recommended to determine the amount of this drug in the blood to control the seizure and prevent its toxicity. In the present study, a simplified and practical procedure based on the dispersive solid phase extraction was implemented and validated to determine Phenytoin in plasma samples. Hydrophobic n-octyl- modified magnetic iron oxide NPs (IONPs) were employed as the sorbent. Methods: The studied drug was detected using high-performance liquid chromatography with a diode array detector. The parameters affecting the extraction efficiency such as pH of the sample, amount of sorbent, time, salt, type and volume of the desorption eluent and desorption time were optimized. After the extraction procedure, magnetic nanoparticless (NPs) were easily separated from the aqueous solution by applying an external magnetic field without the need to filtration or centrifugation.
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Central Composite Design for the Optimization of Hydrogel Based pH-Dependent Extraction and Spectrophotometric Determination of Mercury

Central Composite Design for the Optimization of Hydrogel Based pH-Dependent Extraction and Spectrophotometric Determination of Mercury

The important feature of CPE is the preferable use of water as a solvent in comparison with other pre-treatment techniques that still use hazardous and flammable organic solvents [15]. In recent years, CPE has been combined with a variety of instrumental techniques such as thermospray, flame furnace atomic absorption spectrometry (TS-FF- AAS) [16], chemiluminescence (CL), GF-AAS [17], flame atomic absorption spectrometry (FAAS) [18], gas chromatography (GC) [19], inductively coupled plasma optical emission spectrometry (ICP-OES) [20], tungsten coil electrothermal atomic absorption spectrometry (W-coil ET- AAS) [21,22], inductively coupled plasma mass spectrometry (ICP-MS) [23], capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC) [24]. Recently, we [15] developed a novel and sensitive cloud point extraction procedure using pH-sensitive hydrogel for preconcentration and spectrophotometric determination of trace amounts of malachite green (MG). In this extraction method, appropriate amounts of poly (styrene-alt-maleic acid), as a pH-sensitive hydrogel, and HCl were added, respectively, into the aqueous sample so a cloudy solution was formed. The cloudy phase consisting of hydrogel particles distributed entirely into the aqueous phase. Organic or inorganic compounds having the potential to interact with polymer particles (chemical interaction or physical adsorption) could be extracted to cloudy phase.
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Phytochemical and pharmacological analysis of Pterodon
polygalaeflorus extractsPhytochemical and pharmacological analysis of Pterodon polygalaeflorus extracts

Phytochemical and pharmacological analysis of Pterodon polygalaeflorus extractsPhytochemical and pharmacological analysis of Pterodon polygalaeflorus extracts

Based on the diversified studies demonstrated for Pterodon species and on the findings of diffe- rent intensities of the observed effects, depending upon the extraction procedure, in t[r]

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Optimization of ultrasound assisted extraction of functional ingredients from Stevia rebaudiana Bertoni leaves

Optimization of ultrasound assisted extraction of functional ingredients from Stevia rebaudiana Bertoni leaves

A b s t r a c t. The aim of the present study was to reveal an effective extraction procedure for maximization of the yield of steviol glycosides and total phenolic compounds as well as anti- oxidant activity in stevia extracts. Ultrasound assisted extraction was compared with conventional solvent extraction. The exami- ned solvents were water (100ºC/24 h) and 70% ethanol (at 70°C for 30 min). Qualitative and quantitative analyses of steviol glycosides in the extracts obtained were performed using high performance liquid chromatography. Total phenolic compounds, flavonoids, and radical scavenging capacity by 2, 2-azino-di-3-ethylbenzothi- alozine-sulphonic acid) assay were also determined. The highest content of steviol glycosides, total phenolic compounds, and fla- vonoids in stevia extracts were obtained when ultrasound assisted extraction was used. The antioxidant activity of the extracts was correlated with the total amount of phenolic compounds. The results indicated that the examined sonication parameters repre- sented as the probe diameter (7 and 22 mm) and treatment time (2, 4, 6, 8, and 10 min) significantly contributed to the yield of steviol glycosides, total phenolic compounds, and flavonoids. The optimum conditions for the maximum yield of steviol glycosides, total phenolic compounds, and flavonoids were as follows: extrac- tion time 10 min, probe diameter 22 mm, and temperature 81.2 o C.
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Effect of age on the pharmacokinetics of meloxicam in ISA Brown chickens (Gallus gallus domesticus) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Physiology at Massey University, Palmerston North, Ne

Effect of age on the pharmacokinetics of meloxicam in ISA Brown chickens (Gallus gallus domesticus) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Physiology at Massey University, Palmerston North, New Zealand

The blank bird plasma does not show a retention peak at the same retention time as meloxicam following the same extraction procedure…………………………………………………………………………………………………...112 Figure 30:[r]

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Journal of Applied Pharmaceutical Science

Journal of Applied Pharmaceutical Science

Lai CS, Nair NK, Mansor SM, Olliaro PL, Navaratnam V. An analytical method with a single extraction procedure and two separate high performance liquid chromatographic systems for the determination of artesunate, dihydroartemisinin and mefloquine in human plasma for application in clinical pharmacological studies of the drug combination. J. Chromatogr. B 2007; 857(2): 308-14.

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Volume 7 | Issue 2 - 2017

Volume 7 | Issue 2 - 2017

Pain, anxiety, and stress are different terms of the same entity, which makes the patient restless and uncooperative during any dental procedures. There are different kinds of techniques which were proposed to reduced stress and thereby pain during the procedures. The aim of this study was to compare the efficacy of these alternative techniques in the reduction of stress during dental extraction. Hundred patients, both male and female, in the age group of 15–50 years, were taken as a sample that had to undergo extraction. They were randomly assigned into four groups. Group 1 underwent extraction with no measures of explanation or reduction in anxiety; group 2 underwent extraction where explanation regarding the procedure was given but no aviation methods; group 3 in which patient who underwent extraction was explained about the procedure in music was added as an aviation method; group 4 in which patient who underwent extraction was explained about the procedure and alternative hypnosis using distraction is used. All four groups were subjected to questionnaire before and after extraction procedure, and results of pain levels were recorded in a scales from 1 to 10. Results showed that the group with music showed a good decreased level of anxiety post-operatively, followed by distraction and explanation with a mean value of 8.48, 8.24, and 7.68, respectively. The anxiety levels are higher in males when compared with females. Within the limits of the study, the results show that music reduces pain perception by aviation anxiety in patients undergoing extraction. To the lesser extent, extraction had distraction and instruction may also be used to reduce anxiety in patients. This study helps to understand that reducing anxiety through any one of the technique might be an effective way of pain reduction during the dental surgical procedure.
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DETERMINATION OF PENDIMETHALIN HERBICIDE IN WATER AND VEGETABLE SAMPLES BY MICROWAVE ASSISTED SOLVENT EXTRACTION AND HPLC METHOD

DETERMINATION OF PENDIMETHALIN HERBICIDE IN WATER AND VEGETABLE SAMPLES BY MICROWAVE ASSISTED SOLVENT EXTRACTION AND HPLC METHOD

added and to get high extraction rate, microwave rapid heating were used on closed-vessel during a sample extraction procedure. The starting parameters setting in microwave system were 2.0 min at 350 W and 3.0 min at 500 W. Once the extraction program was completed the vessel were cooled down to room temperature before opening the vessel. After extraction the contents were centrifuged for 10 min and filtered. On equilibration the sample was filtered and the filtrate was evaporated on rotary evaporator up to volume of 2 mL then 5mL of methanol was added to it centrifuged and passed through 0.45 µm pore. The extract was evaporated near to dryness and redissolved in 10 mL of acetonitrile before HPLC analysis.
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Studies on the Extraction of Copper (II) by Pyrazoloquinazolinone Derivatives from Aqueous Solutions

Studies on the Extraction of Copper (II) by Pyrazoloquinazolinone Derivatives from Aqueous Solutions

Extraction Procedure: The prepared standard solution of Cu (II) ions was subjected to several solvent extraction experiments by shaking with the synthesized extractants in carbon tetrachloride. The loaded organic solvents were then contacted with different acidic and alkaline stripping solutions to back extract the copper species from the solvents under the relevant conditions. Factors affecting the extraction and stripping efficiencies of Cu (II) ions with the prepared extractants were investigated. It involved diluents type, aqueous solution pH, solvent concentration, contact time, temperature.
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Detection and Determination of some Migrated Chemicals from Plastic Containers into Different Drinks and Liquids Using Dispersive Liquid-liquid Microextraction Prior to Gas Chromatography

Detection and Determination of some Migrated Chemicals from Plastic Containers into Different Drinks and Liquids Using Dispersive Liquid-liquid Microextraction Prior to Gas Chromatography

Different factors such as storing temperature, physical forces, handling methods, plastic type and presence of oxygen in PET melting procedure can result in thermo- mechanical and thermo-oxidative reactions [28]. Thermal degradation of PET produces many sub-products such as diethylene glycol, aldehydes (formaldehyde, acetaldehyde, and benzaldehyde), aliphatic hydrocarbons, aromatic hydrocarbons (benzene, toluene, and styrene), methanol, etc. Presence of aromatic hydrocarbons in drinks like mineral water can origin from both thermal degradation of PET and their existence in the environment due to various industrial uses such as petroleum, gasoline, diesel fuel, and lubricating and heating oil which eventually enters mineral water sources and contaminate them [29]. Despite the great advancements in analytical techniques and devices in last years, sample preparation is still needed to fulfill the trace amounts analysis. Traditional methods like solid phase extraction and liquid-liquid extraction have been utilized for the pretreatment of analytes in real samples. They are helpful but suffer from drawbacks such as the consumption of organic solvents in large volume, and being laborious and time-consuming [30,31]. Up to now, several analytical approaches have been used for the extraction and analysis of the migrated compounds from plastic bottles [32-35]. For example, Choong and co-workers [36] developed a rapid liquid-liquid extraction procedure followed by gas chromatography-flame ionization detection (GC-FID) for the determination of some antioxidants in edible oils and fats. Marce and co-workers [37] developed a solid phase microextraction method with an 85 µm polyacrylate fiber coupled to gas chromatography-mass spectrometry (GC- MS) for determination of some phthalate esters. Yamini and co-workers [38] also developed a headspace solid phase microextraction method by using a graphene/ polyvinylchloride nanocomposite coated fiber for
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