Top PDF Method of isolating an analyte using a solid phase extraction medium

Method of isolating an analyte using a solid phase extraction medium

Method of isolating an analyte using a solid phase extraction medium

A functionalized macroporous poly(styrene divinylbenzene) particle comprises at least one ionic functional group covalently bonded thereto, the functionalized particle having sorptive capability towards an analyte, said functional group being present in the range of 0.1 to 2.5 milliequivalents per gram of poly(styrene divinylbenzene). The functionalized particles can be used in a packed column or enmeshed in a nonwoven web for utility in solid phase extraction applications.

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A solid-phase extraction method using Transcarpathian clinoptilolite for preconcentration of trace amounts of terbium in water samples

A solid-phase extraction method using Transcarpathian clinoptilolite for preconcentration of trace amounts of terbium in water samples

the other sorbents. For example, these natural alumino- silicate minerals contain pores and cavities with strictly defined size and shape, and it provides very effective concentration and separation of organic and inorganic compounds. In addition, zeolites have mechanical strength, good stability in aggressive medium and under thermal treatment, ability to sorb the trace amounts of analytes, high sorption capacity and selectivity, possibil- ity of easy modification and regeneration of the sor- bent, low cost and accessibility. The sorption properties of Transcarpathian clinoptilolite towards terbium ions were described in our previous work [30]. The aim of this study is to complete these investigations and to develop a simple sample preparation procedure for the spectrophoto- metric detection of trace amounts of terbium ions in aque- ous solutions.
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HERBICIDES   Solid Phase Extraction pdf

HERBICIDES Solid Phase Extraction pdf

Desorption of the compounds from the concentration columns is mainly performed with a small volume of liquid. The partition coef R cient in a given solid- phase eluent system should favour the shift of the studied herbicides. On the other hand, SPE is not a separate step, but it is part of a process that includes subsequent determination and so it should be taken into account that some determination systems, such as GC, are incompatible with the presence of water. In this way, the selection of the eluting solvent de- pends on the selected sorbent, the analytes and the detection method. Air-drying is often applied before analyte elution in order to remove residual water.
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Development and Validation of a HPLC-based Bioanalytical Method for Lorcaserin using Solid Phase Extraction and Application to a Pharmacokinetic Study in Rats

Development and Validation of a HPLC-based Bioanalytical Method for Lorcaserin using Solid Phase Extraction and Application to a Pharmacokinetic Study in Rats

mean peak responses of non-spiked samples prepared in elution solvent and external spiked matrix extracted sample. Recovery of IS in plasma was evaluated by comparing the mean peak responses of at least six MQC samples, prepared in plasma, to mean peak responses of non-spiked samples prepared in elution solvent and external spiked matrix extracted sample, replicates of aqueous samples of LOR. The mean standard deviation and % coefficient of variation (CV) for the peak area ratio and for the retention time of analyte and IS were calculated. Specificity and selectivity was carried out using six plasma samples. Blank (without IS) and zero sample (with IS) were analysed. The linearity of the method was determined over calibration range of 500 to 3000 ng/ml (Table 2). Calibration standards were prepared by spiking known concentration of LOR working standard solution. A linearity curve containing six non-zero concentrations was analysed (fig. 1). Back-calculated the concentrations of each level and plot the graph of back-calculated concentration against drug area ratio. The slope, y-intercept and correlation coefficient curve were calculated by suitable linear regression analysis as stated in Table 3. Accuracy and precision was measured on the samples spiked with known amounts of the analyte. Accuracy and precision were determined by replicate analysis of six determinations of low, medium and HQC sample, which covers the calibration range. Precision is expressed as the % CV. The accuracy and precision were evaluated as within batch and between-batch [14] .
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SOLID PHASE MATRIX DISPERSION   EXTRACTION pdf

SOLID PHASE MATRIX DISPERSION EXTRACTION pdf

The eluates obtained from an MSPD column are often amenable to immediate instrumental analysis, being adequately clean for direct injection. This is, of course, dependent on the sensitivity of the method and whether concentration is required before the analysis. However, in the majority of cases additional steps are required to address the removal of the co- eluting matrix components described above. In a number of cases this additional clean up of the sample has been accomplished by the use of second- ary solid-phase materials. For example, bonded- phase material of the same polarity or even of different character than that used in blending can be packed at the bottom of the MSPD column (co- column). Alternatively, the MSPD column may be eluted directly onto a standard SPE column or disc material for the purposes of conducting further sample clean up and / or analyte concentration. Sim- ilarly, the eluate may be evaporated and reconstituted for application to another form of chromatography, analysis by immunoassay, etc. Other techniques em- ployed to conduct MSPD eluate clean up have in- volved the use of classical liquid } liquid extraction, conducted on a small scale, prior to analysis.
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Development and Validation of Hplc-Ms/Ms Method for Rivaroxaban Quantitation in Human Plasma Using Solid Phase Extraction Procedure

Development and Validation of Hplc-Ms/Ms Method for Rivaroxaban Quantitation in Human Plasma Using Solid Phase Extraction Procedure

The main aim of this work was to develop a rapid, selective and sensitive analytical method including an efficient and reproducible sample clean- up step for quantitative analysis of RXN in human plasma. Chromatographic separation was achieved with Phenomenex Gemini C18, 50×4.6mm,5µm column using mobile phase that consists of a mixture of 5Mm Ammonium formate buffer(pH3.5±0.3): Acetonitrile( 15:85 v/v). ISTD selection should always have similar chromatographic & ionization properties, and recovery of the analyte. Based on these properties of Rivaroxaban and were chosen as internal standards. Strata-x cartridges were used for separation or extract the drug from plasma by SPE. Good chromatograms were obtained with no significant matrix effects. Total runtime was 2.0 min with RT’s of 0.82 for Rivaroxaban and 0.82 for Rivaroxaban D4 respectively. The LC-MS/ MS method described here satisfies the requirement of routine analyses since it has a short run time (2.0 min), which has advantages over other methods described in the literature.
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Optimization of Solid Phase Extraction for Trace Determination of Cobalt (II) Using Chromosorb 102 in Biological Monitoring

Optimization of Solid Phase Extraction for Trace Determination of Cobalt (II) Using Chromosorb 102 in Biological Monitoring

A recently reported method [ 15] has used liquid liquid extraction (LLE) for some heavy metals. Although the technique may be useful in some conditions, however, there are still no basic rules for selection of a solvent system for extraction of given analyte, therefore, selection of a solvent is still empirical and of course time consuming step as well as a tedious stage. Sometimes, emulsion formation of the sample makes the analyte extraction too hard as such solutions are extremely difficult to be broken and often cannot be isolated by either centrifugation or ultra-sonication. Other problems associated with LLE include: the use of large volumes of toxic and sometimes inflammable solvents, contamination of extracts from solvents and glassware, low recovery due to degradation by heat, and volatilization or adsorption to glassware. Therefore, due to such problems, nowadays, there is a strong trend towards replacing LLE by SPE. Based on reported methods [ 20, 22- 24, 26], for optimizing SPE, authors generally have used 5-6 factors to optimize the method for environmental samples [ 23, 31], while, in this study, 9 parameters were screened, including significant factors of sorbent mass, eluent flow rate, sample matrix interferences, and also ligand concentrations. This allows that a robust and more reliable method is introduced for biological monitoring of Co (II). Therefore, to make an advantage from this study compare to the other studies [18-24], further experiments of reproducibility of the method were carried out on spiked urine samples to validate the possible use of the optimized SPE for measuring Co (II) when an environmental study and biological monitoring of worker exposed to such pollutant are required. Although the concentration factor obtained from this study is high, however, the relatively low sensitivity of the AAS did not allowed the authors to get even more concentration factor. Applicability of the optimized method for real samples of urine, hair, and nail can be considered as another advantage of this method.
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Synthesis of selective molecularly imprinted polymer for solid phase
extraction of glipizide by using a pseudo template

Synthesis of selective molecularly imprinted polymer for solid phase extraction of glipizide by using a pseudo template

Glipizide is a sulfonylurea class of antidiabetic drug that can lower blood glucose levels by stimulating the release of insulin from β-cells [1]. This compound is the most potent drug amongst the sulfonylureas [2]. Analytical techniques such as reversed-phase high-performance liquid chromatography [3,4] ion-pair high-performance liquid chromatography [5] and mass spectroscopy liquid chromatography [6] have been developed and used to monitor glipizide level in plasma. These methods have complicated procedures for pretreatment sample and high costs of instruments because of the sample matrices. All the methods need liquid-liquid extraction for the sample separation method. This kind of extraction has a problem in recovery of the sample, needs a lot of time, and has high solvent consumption [7,8].One of the separation methods that is popular is solid-phase extraction (SPE), which is faster, and more efficient than liquid-liquid extraction. However, SPE has low selectivity and this becomes a problem when it deals with complex biological samples or environmental samples or if analyte present in low concentration [8]. Higher selectivity of the sorbent can be increased by using molecular imprinting technique [9].
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Magnetic Molecularly Imprinted Nanoparticles for the Solid-Phase Extraction of Diazinon from Aqueous Medium, Followed Its Determination by HPLC-UV

Magnetic Molecularly Imprinted Nanoparticles for the Solid-Phase Extraction of Diazinon from Aqueous Medium, Followed Its Determination by HPLC-UV

particles were synthesized and the surfaces of them were successfully modified and functionalized in order to dis- perse in organic solvents and take part in the reaction of molecular imprinted polymerization. The obtained @NIP nanoparticles were characte- and XRD analyses. By this method, diazinon can be quantified in the 2-20 ppm concentration range. The recoveries for the aqueous media samples were %, respectively. Besides, the adsorption such as selective adsorption ability, adsorption were investigated by HPLC-UV as well. It could be concluded that the technique has great loping selective extraction method for
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INSECTICIDES   Solid Phase Extraction pdf

INSECTICIDES Solid Phase Extraction pdf

Solid-phase microextraction is a new and simple extraction method which uses fused silica R bres coated with a polymeric liquid phase, such as poly- dimethylsiloxane, or a solid adsorbent, to extract analytes from gaseous, liquid or solid samples. The SPME process has only two steps: (1) partitioning of analytes between the R bre coating and the sample matrix, followed by (2) desorption of extracts into an analytical instrument: gas chromatograph or high- performance liquid chromatograph. SPME is dif- ferent from SPE in that SPE isolates the majority of the analyte ( ' 90%) from a sample but only a small fraction of the sample (1 } 2%) is analysed, while SPME isolates only 2 } 20% of the analyte, but all of that sample is used in the analysis. SPME is solvent- free and it requires small amounts of samples. The SPME devices enable simple and direct introduction of concentrated samples into the analytical instru- ments. These devices are commercially available and the technique has been automated. The SPME technique has a wide linear dynamic range and low detection limits. Since SPME is usually used in the equilibrium rather than exhaustive extraction mode, recoveries are not 100%, but the precision and accu- racy of the analytical methods using SPME are similar to those using other extraction procedures. The cur- rent limitation of SPME is a limited choice of avail- able R bres, especially for the extraction of the more polar insecticides.
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DEVELOPMENT OF ANALYTICAL METHOD FOR IDENTIFICATION OF SIBUTRAMINE HCL IN TRADITIONAL MEDICINE USING SOLID PHASE EXTRACTION – HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

DEVELOPMENT OF ANALYTICAL METHOD FOR IDENTIFICATION OF SIBUTRAMINE HCL IN TRADITIONAL MEDICINE USING SOLID PHASE EXTRACTION – HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Standard solution which was directly injected without going through the SPE cartridge gave high peak of 700 mAu, while the high peak of SPE result only gave <22 mAu. The simulation samples which were diluted with ethanol enable the analyte breakthrough the sorbent. HLB cartridge contains two types of monomer, namely m-divinylbenzene which is lipophilic and n-vinylpyrrolidone which is hydrophilic. Polymer sorbent is more resistant against the effects of water which related with Table 1: Comparison of SPE sibutramine HCl with and without acidification

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SORBENT SELECTION FOR SOLID PHASE EXTRACTION pdf

SORBENT SELECTION FOR SOLID PHASE EXTRACTION pdf

Reversed-phase sorbents are packing materials that are more hydrophobic than the sample. Reversed- phase sorbents are commonly used in SPE when aqueous samples are involved. The mechanism of interaction is Van der Waals forces (also called non- polar, hydrophobic, or reversed-phase interactions) and occasionally secondary interactions such as hy- drogen bonding and dipole } dipole interactions. Size- exclusion sorbents utilize a separation mechanism based on the molecular size of the analyte. It is a method only recently being used in SPE, usually in conjunction with reversed phase or ion exchange. Ion-exchange sorbents isolate analytes based on the ionic state of the molecule, either cationic or anionic,
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Solid phase extraction and determination of indium using multiwalled carbon nanotubes modified with magnetic nanoparticles

Solid phase extraction and determination of indium using multiwalled carbon nanotubes modified with magnetic nanoparticles

In this work MWCNTs-Fe 3 O 4 nanocomposite was used as an adsor- bent for extraction and preconcentration of indium from aqueous so- lutions. The magnetic MWCNTs with adsorbed analytes were easily separated from the aqueous solution by applying an external magnetic field. After elution of the adsorbed analytes, the concentration of indi- um was determined using inductively coupled plasma optical emission spectrometry determination. The effects of pH, sorbent amount, eluent type, chelating reagent concentration, sample volume, and time on the recovery of the In(III) were investigated. Moreover, under the opti- mum conditions, the detection limit for In(III) was 0.28 µg L −1 . The
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Investigation on the insecticidal limonoid content of commercial biopesticides and neem extract using solid phase extraction

Investigation on the insecticidal limonoid content of commercial biopesticides and neem extract using solid phase extraction

aceae is native plant of Southeast Asia and tropical re- gions of the western hemisphere, and its oil is widely used for agricultural pest control as alternative insecti- cides in organic farming [1-6]. It is currently specified as allowable materials in the Environmentally-friendly Ag- riculture Promotion Act in Korea. Limonid was identi- fied as the active component in neem extract. Some li- monoidal compounds such as azadirachtin A, azadira- chtin B, deacetylsalannin and salannin from neem were reported as the major bioactive metabolites, and their insecticidal [3,7-16], antifeedant [17] activities and puta- tive antimicrobial property [18,19] had been reported. These studies recommended neem extract as a potent crop protector. However, commercialization is still a big problem due to the huge variation of azadirachtin content (0.01% - 0.9%) in neem extract by ecotype [10,20] and/ or extraction conditions of the seeds [7,9,21,22].
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Solid-phase extraction derivative aromatic compounds in water samples and determination of using GC-FID

Solid-phase extraction derivative aromatic compounds in water samples and determination of using GC-FID

the trapped analytes on the percolumn were eluted with 2ml of methanol. After derivatization and extraction with a total of 3ml of n-hexane, an aliquot of 2 µl was injected into the GC system. The recover y of phenolic compounds and the repeatability for the different volumes are given in Table 2. Good recoveries were obtained for all compounds studied using 250 ml sample volumes. Of course, when samples of 500 ml were preconcentrated, the recover ies were, still, acceptable, except for phenol. Further experiments revealed that, for less polar compounds, i.e. 3-CP breakthrough volumes higher than 600 ml was obtainable. It was also found that flow rates up to 7ml min -1 for water samples loading on the
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Analysis of inorganic in low explosive residue using solid phase extraction as a pre-concentration technique

Analysis of inorganic in low explosive residue using solid phase extraction as a pre-concentration technique

Identification of explosives becomes crucial due to the need of the investigators to determine its source every time the crimes occur. There are several high and low explosives that are usually used by the criminals. The SPE method provides fast and reliable result in determination of various samples including forensic sample. It is necessary to develop a sample preparation method that enables determination of the targeted ions at lower concentration level.

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In line solid phase extraction for sensitivity enhancement in capillary electrophoresis

In line solid phase extraction for sensitivity enhancement in capillary electrophoresis

2. Thabano J.R.E., Breadmore M.C., Johns C., Hutchinson J.P., Haddad P.R., Selective Extraction and Elution of Weak Bases by In-Line Solid-Phase Extraction Capillary Electrophoresis using a pH Step Gradient and a Weak Cation-Exchange Monolith , Analyst 133, 2008,1380-1387 (Chapter 5).

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Developments/Application of Ionic Liquids/Poly Ionic Liquids in Magnetic Solid-Phase Extraction and Solid Phase Microextraction

Developments/Application of Ionic Liquids/Poly Ionic Liquids in Magnetic Solid-Phase Extraction and Solid Phase Microextraction

Several nanomaterials have been investigated as solid phase sorbents for this technique, such as carbon nanotubes, graphene oxide and molecularly imprinted nanoparticles [51], [52]. Particularly, nanoparticles contain magnetic components allow convenient and highly efficient enrichment. Nanoparticles are dispersed into the sample solution, and after adsorption process, they are easily separated from the matrix by applying an external magnet while the solution is discarded. Then, the target analytes are desorbed with a suitable solution and nanoparticles are regenerated for reusing as it is shown schematically in Figure 2.
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Review of procedures involving separation and Solid Phase Extraction for the determination of cadmium using spectrometric techniques

Review of procedures involving separation and Solid Phase Extraction for the determination of cadmium using spectrometric techniques

An SPE method is always composed of three to four successive steps, as illustrated in Fig. 1.. First, a solid sorbent should be swirled with a suitable solvent (as a solvent). This step is important because it moisturizes the absorbent and activates the absorbent groups. In addition, the removal of possible impurities that are initially present in the sorbent is eliminated. Also, at this stage, the air contained in the column is removed and the saturated volume of the adsorbent is filled with solvent. Typically, methanol is used to activate the depleting phase (such as octadecyl-bonded silica), followed by water or a water buffer whose pH and ionic strength are similar to the sample. Care should be taken to ensure that no solids are absorbed between the two stages of elution and the passage of the adsorbent sample, otherwise the analytes will not be maintained effectively and poor results will be achieved. If the sorbent is dried for more than a few minutes, it should be re-modified.
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Analysis of inorganic cations in low explosive residue using solid phase extraction as a pre-concentration technique

Analysis of inorganic cations in low explosive residue using solid phase extraction as a pre-concentration technique

Identification of explosives becomes crucial due to the need of the investigators to determine its source every time the crimes occur. There are several high and low explosives that are usually used by the criminals. The SPE method provides fast and reliable result in determination of various samples including forensic sample. It is necessary to develop a sample preparation method that enables determination of the targeted ions at lower concentration level.

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