Selective Extraction Method Research Articles

Safety and efficacy of selective sac extraction method of inguinal hernia repair in children: results of a prospective study

A prospective study was conducted to confirm the safety and efficacy of the selective sac extraction method (SSEM) of inguinal hernia repairs in children. Primary endpoints of the study were the incidence of any complication related to the SSEM, or hernia recurrence. Secondary endpoints included the success rate of the SSEM, length of incision at the end of operation, and duration of operation. The incidence of contralateral manifestation of hernia was also examined. Between October 2009 and December 2011, a total of 317 repairs, 145 male repairs and 172 female repairs, were performed by applying the SSEM. There were three operative conversions, and the success rate of the SSEM was 99% in both male and female patients. The length of incision ranged from 4.0 to 12.5 mm (median 6.0 mm) and was ≤7.0 mm in 93% repairs. The incisional length for male repairs ranged from 4.0 to 12.5 mm (median 6.0 mm) and was ≤7.0 mm in 86% repairs, while it ranged from 4.0 to 9.0 mm (median 5.5 mm) in female repairs and was ≤6.5 mm in 96% repairs. The duration of the operation for unilateral repair ranged from 9 to 66 min (median 21 min). Eighty percent of repairs were examined 6-44 months (median 12 months) after the operation. There was one (0.4%) recurrence among 250 repairs and two (1.7%) cases of testicular dislocation among 115 male repairs. Contralateral hernia presented in 19 (9.5%) of 199 patients with unilateral hernia who underwent the follow-up. The feasibility of the SSEM was reconfirmed, and it was revealed that the complication and recurrence rates were low and acceptable. The SSEM is safe and effective, and should be a standard method for repairing inguinal hernia in children.

Efficient recovery of whole cell proteins in Oenococcus oeni—a comparison of different extraction protocols for high-throughput malolactic starter applications

In this study, we compared different total protein extraction protocols to achieve highly efficient isolation and purification of total proteins for the specific protein profiling of Oenococcus oeni. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns obtained for the different extraction protocols revealed not only a qualitative similar protein pattern but also quantitative variations with different intensity bands depending on the extraction method used. The selected extraction method added with sonication proved to work extremely well and efficiently and was able to obtain a high-resolution 2-D electrophoresis (2-DE) map. Prominent spots were successfully identified by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry and corresponded to 76 different proteins involved in the main metabolic pathways. The approach allowed to achieve a protein profiling specific for O. oeni from Aglianico wine with numerous characterized protein products corresponding to many different O. oeni genes and associated with main cellular pathways. Further investigations of the 2-DE protein expression profile will provide useful and interesting information on the molecular mechanisms at the protein level responsible for growth and survival of O. oeni in wine.

Solid-phase extraction approach for phospholipids profiling by titania-coated silica microspheres prior to reversed-phase liquid chromatography-evaporative light scattering detection and tandem mass spectrometry analysis.

A novel strategy for selectively adsorbing phospholipids (PLs) on titania-coated silica core-shell microspheres (TiO2/SiO2) was developed. The TiO2/SiO2 microspheres were prepared through water-vapor-induced internal hydrolysis and then characterized by SEM, UV-vis spectroscopy, X-ray diffraction, and measurements of Brunauer-Emmett-Teller surface area. Analyses showed that the titania layer was uniformly distributed onto the surface of silica particles. The TiO2/SiO2 microspheres were employed as sorbent in solid-phase extraction (SPE), and their absorptive ability was investigated by reversed-phase liquid chromatography-evaporative light scattering detection (RPLC-ELSD). Important factors that affect the extraction, such as loading buffer, eluting buffer, and elution volume, were investigated in detail and optimized by using standard samples. Results reveal that the developed SPE approach had higher recoveries for PLs than that based on pure TiO2 particles. The proposed SPE method was used for extraction of PLs from serum and showed great potential for identifying more kinds of endogenous PL metabolites by ultra performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-QTOF MS). The proposed SPE method with the composite sorbent was used to screen PLs from a biological matrix with high selectivity and efficiency. This approach is a promising method for selective extraction of PLs in lipidomics or phospholipidomics.

Phase associations and potential selective extraction methods for selected high-tech metals from ferromanganese nodules and crusts with siderophores

Deep-sea ferromanganese deposits contain a wide range of economically important metals. Ferromanganese crusts and nodules represent an important future resource, since they not only contain base metals such as Mn, Ni, Co, Cu and Zn, but are also enriched in critical or rare high-technology elements such as Li, Mo, Nb, W, the rare earth elements and yttrium (REY). These metals could be extracted from nodules and crusts as a by-product to the base metal production. However, there are no proper separation techniques available that selectively extract certain metals out of the carrier phases. By sequential leaching, we demonstrated that, except for Li, which is present in an easily soluble form, all other high-tech metals enriched in ferromanganese nodules and crusts are largely associated with the Fe-oxyhydroxide phases and only to subordinate extents with Mn-oxide phases. Based on this fact, we conducted selective leaching experiments with the Fe-specific organic ligand desferrioxamine-B, a naturally occurring and ubiquitous siderophore. We showed by leaching of ferromanganese nodules and crusts with desferrioxamine-B that a significant and selective extraction of high-tech metals such as Li, Mo, Zr, Hf and Ta is possible, while other elements like Fe and the base metals Mn, Ni, Cu, Co and Zn are not extracted to large extents. The set of selectively extracted elements can be extended to Nb and W if Mn and carbonate phases are stripped from the bulk nodule or crust prior to the siderophore leach by e.g. a sequential leaching technique. This combination of sequential leaches with a siderophore leach enhanced the extraction to 30–50% of each Mo, Nb, W and Ta from a mixed type Clarion-Clipperton Zone (CCZ) nodule and 40–80% from a diagenetic Peru Basin nodule, whilst only 5–10% Fe and even less Mn are extracted from the nodules. Li is extracted to about 60% from the CCZ nodule and a maximum of 80% Li is extracted from the Peru Basin nodule.Our pilot work on selective extraction of high-tech metals from marine ferromanganese nodules and crusts showed that specific metal-binding organic ligands may have promising potential in future processing technologies of these oxide deposits.

Comparison of three phenotypic and deoxyribonucleic acid extraction methods for isolation and Identification of Nocardia spp.

Background:The aerobic Actinomycetes are a large group of soil-indwelling bacteria that are distributed in world-wide. These Gram-positive bacteria are most commonly associated with opportunistic infections in both immunocompromised and immunocompetent hosts.Materials and Methods:In this study, three phenotypic and deoxyribonucleic acid (DNA) extraction methods for isolation and identification of Nocardia genus were compared. Samples were taken in five different locations of Isfahan's suburb from hospitals area, parks, agricultural lands, gardens, arid lands with different soil temperature and pH.Results:In this study, showed that slip-buried-method was better than two other phenotypic methods; 14 out of 70 soil samples (20%) were positive for Nocardia spp. DNA of positive samples were extracted with three techniques and DNA extraction by microwave technique was better than others. This technique was confirmed with observation of DNA bands on 1% agarose gel.Conclusions:These bacteria are important in immune deficient patients such as cancer patients, transplant recipients, tuberculosis; acquired immunodeficiency syndrome etc., Their affluence is unsteady in different zones of the world. In this study, among the three phenotypic methods for the isolation of Nocardia slip-buried method was better than other methods. Among DNA extraction techniques, DNA extraction by microwave method would be selective method for DNA extraction of Nocardia spp. compared with others techniques.

Fibrous Agricultural Biomass as a Potential Source for Bioconversion to Vanillic Acid

This study was conducted to assess the potential of six fibrous agricultural residues, namely, oil palm empty fruit bunch fiber (OPEFBF), coconut coir fiber (CCF), pineapple peel (PP), pineapple crown leaves (PCL), kenaf bast fiber (KBF), and kenaf core fiber (KCF), as a source of ferulic acid and phenolic compounds for bioconversion into vanillic acid. The raw samples were pretreated with organosolv (NaOH-glycerol) and alkaline treatment (NaOH), to produce phenol-rich black liquor. The finding showed that the highest amount of phenolic compounds and ferulic acid was produced from CCF and PP, respectively. This study also found that organosolv treatment was the superior method for phenolic compound extraction, whereas alkaline treatment was the selective method for lignin extraction. Vanillic acid production byAspergillus nigerI-1472 was only observed when the fermentation broth was fed with liquors from PP and PCL, possibly due to the higher levels of ferulic acid in those samples.

Time evolution of Pb(II) speciation in Pampa soil fractions

Soil pollution by heavy metals, particularly lead, is an important environmental concern; the bioavailability of such pollutants is strongly dependent on their chemical form. Here, the speciation of Pb(II) in soil fractions as a function of time shortly after its incorporation is studied, using a selective sequential extraction method. The sample came from an Argentinean Pampas region and was extensively characterised, including Rietveld analysis of the silt+clay fraction XRD pattern to find the major mineral components. Experiments were run twice, once in the winter and once in the summer. The results show different speciation time profiles in both cases, showing faster changes in winter due to the higher water content. The summer experiment corresponds to an earlier stage in the speciation profile evolution compared with winter. The soluble/exchangeable fraction decreases with time in summer but shows a lower and constant value in the winter. A high proportion is found to be adsorbed onto the stable (aluminosilicates+quartz) mineral fraction. The results strongly suggest that, even at a short time following soil pollution with Pb, a high proportion is adsorbed onto the mineral fraction, with only a low fraction being bioavailable. The most stable (mineral incorporated) form is observed to increase with time. Soil water content appears to be more important than temperature in determining the differences between the two.

Enzymatic Biosensor Associated with Molecularly Imprinted Polymers for Sensitive and Selective Detection of Organophosphorus Insecticides in Olive Oil

5 different bio-tools have been developed for sensitive detection of three organophosphorus insecticides mainly used for the treatment of olive trees: Malaoxon, Omethoate and Methidathion-oxon. The systems are based on the immobilization of electric eel acetylcholinesterase on screen-printed electrode (SPE) and microtiter plates by 3 different methods of immobilization. These developed systems were optimized with laboratory samples and then tested on natural samples of olive oil after a simple liquid-liquid extraction. Among these five systems designed, the amperometric biosensor based on acetylcholinesterase immobilized by bioencapsulation in a sol-gel matrix presented the best performance in terms of operational stability, storage stability, reproducibility, and it proved to be best suited for the determination of insecticides in real samples of olive oil. This biosensor has been associated with a highly selective extraction method based on the use of Molecularly Imprinted Polymers (MIPs) to improve selectivity. The results showed that the association MIPs-biosensor can selectively detect and quantify the three organophosphorus insecticides in such a complex matrix as olive oil, with limits of detection much lower than the maximum residue limit tolerated by international regulations.

An improved selective extraction method for Mn oxides and occluded metals with emphasis on applicability to Andisols

It has been showed that Chao’s method [extraction with 0.1 mol L−1 hydroxylamine hydrochloride (NH2OH-HCl) at pH 2.0 for 30 min], which is commonly used to extract manganese (Mn) oxides and occluded heavy metals from soil samples, is not suitable for Andisols because of low solubility, and thus low extractability, of Mn oxides in such soils. Therefore, a new method is evaluated here, for extracting Mn oxides and occluded heavy metals from Andisols, Entisols and Inceptisols. The method has three steps: (1) reduction of Mn oxides with 0.01 mol L−1 NH2OH-HCl (pH 5.0) for 16 h, (2) recovery of re-adsorbed metals by short-time extraction with 0.5 mol L−1 ammonium chloride in 0.02 mol L‒1 hydrochloric acid, and (3) washing with ultrapure water. This method achieves a higher rate of extraction of Mn oxides than does Chao’s method, especially from Andisol samples. Standard addition experiments showed that both the new method and Chao’s method can successfully extract released cadmium (Cd), cobalt (Co), nickel (Ni) and zinc (Zn) from Mn oxides with little re-adsorption. The selectivity of Mn oxide extraction by the new method, indicated by the rate of extraction of iron (Fe) oxides and the aluminum (Al)/Mn and silicon (Si)/Mn extraction ratios, is comparable to that of Chao’s method. Thus, the new method should be useful for extracting Mn oxides and occluded Cd, Co, Ni, and Zn from soil samples. Moreover, because the new method achieved nearly complete extraction of NH2OH-HCl reactive Mn oxides even from Andisol samples, the method is more applicable to Andisol samples than Chao’s method.

Synthesis, characterization and analytical application of Zn(II)-imprinted polymer as an efficient solid-phase extraction technique for trace determination of zinc ions in food samples

Zinc imprinted polymer (Zn(II)-IIP) as a solid-phase extraction technique was applied for preconcentration and determination of zinc in environmental and food samples by FAAS. Zn(II)-IIP was synthesized by copolymerization of 2-vinylpyridine as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linker, 2,2-azobisisobutyronitrile as the initiator, Zn(NO3)2 as the template ion, diphenylcarbazone as the ligand, and methanol/dichloromethane (50:50) as the solvent. The synthesized polymer particles were characterized by thermogravimetry analysis (TGA), differential thermal analysis (DTA), scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FT-IR), and X-ray diffraction (XRD). The optimization process was carried out using the central composite design (CCD). With this design, the optimum conditions for the adsorption step were 6.6, 30mg, and 23min, for pH, mass of polymer and adsorption time respectively, and for desorption step the optimal conditions were 14mL, 12% (v/v), and 23min, for volume of eluent, concentration of eluent, and desorption time, respectively. Under the optimized conditions, the detection limit of the proposed method was found to be 0.15μgL−1, while the relative standard deviation (RSD) for 10 replicate measurements was calculated to be 2.8%. Therefore the introduced selective solid phase extraction method can be used as a reliable technique for selective and sensitive trace detection of zinc in different food matrixes, and the reliability of the proposed solid phase extraction technique was established by the analysis of standard reference materials.

The selective leaching and separation of molybdenum from complex molybdenite concentrate containing copper

In recent years, there has been an increasing focus on the hydrometallurgical processing of molybdenite, with the decline of high-grade and easily handled molybdenum minerals. In this work, a novel method of selective extraction of complex molybdenite concentrate, which is characteristic of high-grade copper ore, has been investigated. The results show that the leaching of chalcopyrite was impacted by the pH of the electrolyte when sodium carbonate and ammonium acid carbonate were added to the electrolyte. The leaching rate of molybdenum reached 99.39%, but chalcopyrite could not be leached at all in 240 min under experimental conditions of liquid-to-solid ratio 25:1, concentration of NaCl 4 mol/L, pH=9, room temperature and agitation speed 400 rpm. The grade of copper in the residue was 21.84%, with a recovery 99.93%. The technology of selective electro-oxidation leaching of molybdenum and recovery of copper from complex molybdenite concentrate is an effective separation method. The diffusion control model can be used to describe the process of leaching of molybdenum. The activation energy of the leaching reaction was found to be approximately 9.21 kJ/mol.

Molecularly imprinted microspheres and nanoparticles prepared using precipitation polymerisation method for selective extraction of gallic acid from Emblica officinalis

This paper reports the preparation of gallic acid (GA) molecularly imprinted polymers (MIPs) by the precipitation polymerisation and highlights the effect of porogen on particle size and specific molecular recognition properties. MIP, M-100 prepared in the porogen acetonitrile and MIP, M-75 prepared in a mixture of acetonitrile-toluene (75:25 v/v), resulted in the formation of microspheres with approximately 4μm particle size and surface area of 96.73m2g−1 and nanoparticles (0.8–1000nm) and a surface area of 345.9m2g−1, respectively. The Langmuir–Freundlich isotherm study revealed that M-75 has comparatively higher number of binding sites which are homogenous and has higher affinity for GA. The MIPs selectively recognised GA in presence of its structural analogues. Pure GA with percent recovery of 75 (±1.6) and 83.4 (±2.2) was obtained from the aqueous extract of Emblica officinalis by M-100 and M-75, respectively and hot water at 60°C served as the eluting solvent.

Evaluation of selective extraction methods for recovery of polyphenols from pine

Abstract The extraction conditions have been evaluated concerning the recovery of specific polyphenols from Scots pine (Pinus sylvestris) knots by means of an accelerated solvent extractor. The composition of the extracts was determined by gas chromatography, gas chromatography-mass spectrometry, and high-performance size-exclusion chromatography. The main phenolic compounds are the stilbenes pinosylvin and its monomethyl ether and the lignan nortrachelogenin (NTG), and their amounts vary a lot from sample to sample. The sequential extraction with a nonpolar solvent as a first step for removing the lipophilic compounds was the most efficient approach for the recovery of both pinosylvins and NTG. For food applications, hot water and 85% aqueous ethanol were good solvents for the production of the substances in focus. An industrial knotwood sample from a pulp mill was sequentially extracted with cyclohexane and ethanol/water (95:5) in a large-scale Soxhlet equipment. The results show that the industrial production of pinosylvins and NTG from knots is feasible.

Ultratrace determination of arsenic in water samples by electrothermal atomic absorption spectrometry after pre-concentration with Mg–Al–Fe ternary layered double hydroxide nano-sorbent

A selective solid phase extraction method, based on nano-structured Mg–Al–Fe(NO3−) ternary layered double hydroxide as a sorbent, is developed for the pre-concentration of ultra-trace levels of arsenic (As) prior to determination by electrothermal atomic absorption spectrometry. It is found that both As(III) and As(V) could be quantitatively retained on the sorbent within a wide pH range of 4–12. Accordingly, the presented method is applied to determination of total inorganic As in aqueous solutions. Maximum analytical signal of As is achieved when the pyrolysis and atomization temperatures are close to 900°C and 2300°C, respectively. Several variables affecting the extraction efficiency including pH, sample flow rate, amount of nano-sorbent, elution conditions and sample volume are optimized. Under the optimized conditions, the limit of detection (3Sb/m) and the relative standard deviation are 4.6pgmL−1 and 3.9%, respectively. The calibration graph is linear in the range of 15.0–650pgmL−1 with a correlation coefficient of 0.9979, sorption capacity and pre-concentration factor are 8.68mgg−1 and 300, respectively. The developed method is validated by the analysis of a standard reference material (SRM 1643e) and is successfully applied to the determination of ultra-trace amounts of As in different water samples.

Determination of polychlorinated biphenyls in soil and sediment by selective pressurized liquid extraction with immunochemical detection

A selective pressurized liquid extraction (SPLE) method was developed for a streamlined sample preparation/cleanup to determine Aroclors and coplanar polychlorinated biphenyls (PCBs) in soil and sediment. The SPLE was coupled with an enzyme-linked immunosorbent assay (ELISA) for an effective analytical approach for environmental monitoring. Sediment or soil samples were extracted with alumina, 10% AgNO3 in silica, and sulfuric acid impregnated silica with dichloromethane at 100°C and 2000psi. The SPLE offered simultaneous extraction and cleanup of the PCBs and Aroclors, eliminating the need for a post-extraction cleanup prior to ELISA. Two different ELISA methods: (1) an Aroclor ELISA and (2) a coplanar PCB ELISA were evaluated. The Aroclor ELISA utilized a polyclonal antibody (Ab) with Aroclor 1254 as the calibrant and the coplanar PCB ELISA kit used a rabbit coplanar PCB Ab with PCB-126 as the calibrant. Recoveries of Aroclor 1254 in two reference soil samples were 92±2% and 106±5% by off-line coupling of SPLE with ELISA. The average recovery of Aroclor 1254 in spiked soil and sediment samples was 92±17%. Quantitative recoveries of coplanar PCBs (107–117%) in spiked samples were obtained with the combined SPLE–ELISA. The estimated method detection limit was 10ngg−1for Aroclor 1254 and 125pgg−1 for PCB-126. Estimated sample throughput for the SPLE–ELISA was about twice that of the stepwise extraction/cleanup needed for gas chromatography (GC) or GC/mass spectrometry (MS) detection. ELISA-derived uncorrected and corrected Aroclor 1254 levels correlated well (r=0.9973 and 0.9996) with the total Aroclor concentrations as measured by GC for samples from five different contaminated sites. ELISA-derived PCB-126 concentrations were higher than the sums of the 12 coplanar PCBs generated by GC/MS with a positive correlation (r=0.9441). Results indicate that the SPLE–ELISA approach can be used for quantitative or qualitative analysis of PCBs in soil and sediments. To our knowledge, this is the first report of an SPLE–ELISA approach not requiring a post-extraction cleanup step for detecting Aroclors and coplanar PCBs in soil and sediment.

Synthesis of novel aniline immobilized silica gel for the selective extraction of Cr(III)

Aniline moiety was immobilized on the surface of silica gel (SG) through functionalizing the later by 3-chloropropyl trimethoxysilane (3-CPTS). The aniline immobilization was confirmed by chemical, Fourier transform infrared (FTIR), thermo gravimetric analysis (TGA), and scanning electron microscopy (SEM). Solid phase extraction (SPE) property of the synthesized product was studied in terms of Cr(III) uptake by batch and column methods. Metal ion adsorption and its isotherm, kinetic and thermodynamic parameters were evaluated. The mechanistic path involved in up taking metal ion has been suggested. The Cr(III) binding capacity was found to be 8.7 mg g−1 at trace level of chromium in aqueous medium. The presence of chloride ion improved the metal ion binding capacity as well as selectivity to a significant extent. The developed material and the selective extraction method were tested by applying it in real samples and the results were compared with the reported values.

Solid-phase extraction of galloyl- and caffeoylquinic acids from natural sources (Galphimia glauca and Arnicae flos) using pure zirconium silicate and bismuth citrate powders as sorbents inside micro spin columns

Galloyl- and caffeoylquinic acids are among the most important pharmacological active groups of natural compounds. This study describes a pre-step in isolation of some selected representatives of these groups from biological samples. A selective solid-phase extraction (SPE) method for these compounds may help assign classes and isomer designations within complex mixtures. Pure zirconium silicate and bismuth citrate powders (325 mesh) were employed as two new sorbents for optimized SPE of phenolic acids. These sorbents possess electrostatic interaction sites which accounts for additional interactions for carbon acid moieties as compared to hydrophilic and hydrophobic sorbents alone. Based on this principle, a selective SPE method for 1,3,4,5-tetragalloylquinic acid (an anti-HIV and anti-asthamatic agent) as a starting compound was developed and then deployed upon other phenolic acids with success. The recoveries and selectivities of both sorbents were compared to most commonly applied and commercially available sorbents by using high performance liquid chromatography. The nature of interaction between the carrier sorbent and the acidic target molecules was investigated by studying hydrophilic (silica), hydrophobic (C18), mixed-mode (ionic and hydrophobic: Oasis® MAX) and predominantly electrostatic (zirconium silicate) materials. The newly developed zirconium silicate and bismuth citrate stationary phases revealed promising results for the selective extraction of galloyl- and caffeoylquinic acids from natural sources. It was observed that zirconium silicate exhibited maximum recovery and selectivity for tetragalloylquinic acid (84%), chlorogenic acid (82%) and dicaffeoylquinic acid (94%) among all the tested sorbents.

From soil to leaves – Aluminum fractionation by single step extraction procedures in polluted and protected areas

The paper presents the fractionation of aluminum in the samples of soil and plants of different species using a selective single-step extraction method. The study was conducted in the area located near a chemical plant, which for many years served as a post-crystallization leachate disposal site storing chemical waste (sector I), and in the area around the site: in Wielkopolski National Park, Rogalin Landscape Park and toward the infiltration ponds at the “Dębina” groundwater well-field for the city of Poznań (Poland) (sector II). The results of aluminum fractionation in samples of soil, leaves and plants showed heavy pollution with aluminum, especially in the water soluble aluminum fraction – Alsw (maximum concentration of aluminum in soil extract was 234.8 ± 4.8 mg kg−1, in the leaves of Betula pendula it was 107.4 ± 1.8 mg kg−1 and in the plants of Artemisia vulgaris (root) and Medicago sativa (leaves) it amounted to 464.7 ± 10.7 mg kg-1and 146.8 ± 1.2 mg kg−1 respectively). In addition, the paper presents the problem of organic aluminum fractionation in biological samples and it shows the relationship between aluminum concentration in soil and the analysed woody and herbaceous species.

Green methodology for the recovery of Cr (VI) from tannery effluent using newly synthesized quaternary ammonium salt

Leather tanning industries release effluents into the river through various canals. These effluents contain chromium (VI) contaminating the river and the ground water as well. To fix a solution for this issue a simple and selective solvent extraction method has been applied by using a newly synthesized quaternary ammonium salt viz 2-benzoylethylheptyldimethylammonium bromide. By varying the parameters such as quaternary ammonium salts, sulfuric acid, pH, solvents, equilibration time and aqueous organic ratio the extraction efficiency has been determined.

Development of a selective solid phase extraction method for nitro musk compounds in environmental waters using a molecularly imprinted sorbent

A powerful analytical method for the determination of the family of the nitro musk compounds at trace level in environmental waters—river, sea, and water from a treatment plant—is presented. The method is based on the use of molecularly imprinted silica (MIS) as sorbent for solid phase extraction (SPE) used for the clean-up and the concentration step of the target analytes previous to their determination by gas chromatography–mass spectrometry. The optimized extraction procedure allowed extraction recoveries between 61% and 87% using the MIS. The comparison with a non-imprinted silica (NIS) sorbent, for which extraction recoveries between 8% and 26% were obtained, showed the high selectivity of the MIS for the nitro musks. Moreover, high enrichment factors, ranging between 580 and 827, were achieved. The imprinted sorbent was compared to a conventional polymeric SPE sorbent for the extraction of the target compounds from environmental waters, showing high selectivity of the MIS and its clean-up potential. For the first time, the five nitro musk compounds were selectively extracted with an imprinted material.