Solid Phase Microextraction Fibers Coated with Sol-gel Aminopropylsilica/polydimethylsiloxane: Development and Its Application to Screening of Beer Headspace

The preparation and applicability of solid phase microextraction (SPME) fibers coated with a sol-gel organically modified silica based on 3-aminopropyltrimethoxysilane and polydimethylsiloxane (APTMS/PDMS) are described here. Micrographs of the coated fibers revealed a rugous surface; the thickness of the coating was estimated to be less than 30 microm. The APTMS/PDMS fibers were tested with synthetic samples and compared to commercial fibers for headspace SPME analysis of beer. Extraction and desorption using the APTMS/PDMS fibers were faster, which is typical for sol-gel SPME fibers. For polar and semi-polar compounds on beer headspace, the extraction efficiencies of the APTMS/PDMS fiber were superior to those of conventional fibers. The APTMS/PDMS fiber was found to be capable of extracting a broad range of analytes, including highly polar acidic species such as organic acids.     

Air/polymer distribution coefficients for polycyclic aromatic hydrocarbons by solid-phase microextraction sampling

Two methods to estimate distribution coefficients (K) between air and poly(dimethylsiloxane) (PDMS) coating of solid-phase microextraction (SPME) fibers for eight low molecular polycyclic aromatic hydrocarbons (PAHs) there are presented. The PDMS phases were used for determination of the coefficients according to equilibrium theory with help of a developed static calibration system (SCS). Another way to estimate the coefficients is based on the use of a linear relationship between the logarithm of the coefficients (log K) and linear temperature-programmed retention indexes (LTPRI) of the compounds without necessity to calibrate. The log K values for both of methods ranged from 5.2 (naphthalene) to 8.9 (pyrene) at 22 degrees C. Relative standard deviation (R.S.D.) of log K for each compound determined by static calibration was no more than 5.3%. R.S.D. of retention times for LTPRI indices did not exceed 0.28% for repeated injection. All experiments were implemented on a GC-MS system.     

Methodical evaluation and improvement of matrix compatible PDMS-overcoated coating for direct immersion solid phase microextraction gas chromatography (DI-SPME-GC)-based applications

The main quest for the implementation of direct SPME to complex matrices has been the development of matrix compatible coatings that provide sufficient sensitivity towards the target analytes. In this context, we present here a thorough evaluation of PDMS-overcoated fibers suitable for simultaneous extraction of different polarities analytes, while maintaining adequate matrix compatibility. For this, eleven analytes were selected, from various application classes (pesticides, industrial chemicals and pharmaceuticals) and with a wide range of log P values (ranging from 1.43 to 6). The model matrix chosen was commercial Concord grape juice, which is rich in pigments such as anthocyanins, and contains approximately 20% of sugar (w/w). Two types of PDMS, as well as other intrinsic factors associated with the PDMS-overcoated fiber fabrication are studied. The evaluation showed that the PDMS-overcoated fibers considerably slowed down the coating fouling process during direct immersion in complex matrices of high sugar content. Longevity differences could be seen between the two types of PDMS tested, with a proprietary Sylgard^® giving superior performance because of lesser amount of reactive groups and enhanced hydrophobicity. Conversely, the thickness of the outer layer did not seem to have a significant effect on the fiber lifetime. We also demonstrate that the uniformity of the overcoated PDMS layer is paramount to the achievement of reliable data and extended fiber lifetime. Employing the optimum overcoated fiber, limits of detection (LOD) in the range of 0.2–1.3 ng/g could be achieved. Additional improvement is attainable by introducing washing of the coatings after desorption, so that any carbon build-up (fouling) left on the coating surface after thermal desorption can be removed.     

New approach based on solid-phase microextraction to estimate polydimethylsiloxane fibre coating-water distribution coefficients for brominated flame retardants

A depletion solid-phase microextraction (SPME) method based on multiple SPME extraction was applied to estimate fibre coating-water distribution constants (Kfs) of brominated flame retardants. Several polybrominated diphenyl ethers (PBDEs) including compounds present in the commercial mixture "Pentamix", and two polybrominated biphenyls (PBBs) were considered as target analytes. One hundred-micrometer poly(dimethylsiloxane) (PDMS) coating fibre was selected to estimate partition coefficients. SPME kinetics studies at 25 and 100 degrees C were performed. Kfs values obtained at both temperatures for brominated flame retardants were compared with the corresponding octanol-water partition coefficients (Kow) values found in literature. A linear log-log relationship between Kow with Kfs was found. To the best of our knowledge, this is the first study where brominated flame retardants Kfs values are estimated.     

Optimization of the derivatization reaction and the solid-phase microextraction conditions using a D-optimal design and three-way calibration in the determination of non-steroidal anti-inflammatory drugs in bovine milk by gas chromatography-mass spectrometry

An experimental design optimization is reported of an analytical procedure used in the simultaneous determination of seven non-steroidal anti-inflammatory drugs (NSAIDs) in bovine milk by gas chromatography with mass spectrometry detection (GC-MS). This analytical procedure involves a solid-phase microextraction (SPME) step and an aqueous derivatization procedure of the NSAIDs to ethyl esters in bovine milk. The following NSAIDs are studied: ibuprofen (IBP), naproxen (NPX), ketoprofen (KPF), diclofenac (DCF), flufenamic acid (FLF), tolfenamic acid (TLF) and meclofenamic acid (MCL). Three kinds of SPME fibers - polyacrylate (PA), polydimethylsiloxane/divinylbenzene (PDMS/DVB) and polydimethylsiloxane (PDMS) - are compared to identify the most suitable one for the extraction process, on the basis of two steps: to determine the equilibrium time of each fiber and to select the fiber that provides the best figures-of-merit values calculated with three-way PARAFAC-based calibration models at the equilibrium time. The best results were obtained with the PDMS fiber. Subsequently, 8 experimental factors (related to the derivatization reaction and the SPME) were optimized by means of a D-optimal design that involves only 14 rather than 512 experiments in the complete factorial design. The responses used in the design are the sample mode loadings of the PARAFAC decomposition which are related to the quantity of each NSAID that is extracted in the experiment. Owing to the fact that each analyte is unequivocally identified in the PARAFAC decomposition, a calibration model is not needed for each experimental condition. The procedure fulfils the performance requirements for a confirmatory method established in European Commission Decision 2002/657/EC.     

Highly porous solid-phase microextraction fiber coating based on poly(ethylene glycol)-modified ormosils synthesized by sol-gel technology

The preparation and characteristics of solid-phase microextraction (SPME) fibers coated with Carbowax 20M ormosil (organically modified silica) are described here. Raw fused silica fibers were coated with Carbowax 20M-modified silica using sol-gel process. Scanning electron micrographs of fibers revealed a highly porous, sponge-like coating with an average thickness of (8 +/- 1) microm. The sol-gel Carbowax fibers were compared to commercial fibers coated with 100 microm polydimethylsiloxane (PDMS) and 65 microm Carbowax-divinylbenzene (DVB). Shorter equilibrium times were possible with the sol-gel Carbowax fiber: for headspace extraction of the test analytes, they ranged from less than 3 min for benzene to 15 min for o-xylene. Extraction efficiencies of the sol-gel Carbowax fiber were superior to those of conventional fibers: for o-xylene, the extracted masses were 230 and 540% of that obtained with 100 microm PDMS and 65 microm Carbowax-DVB fibers, respectively.     

Determination of diphenylether herbicides in water samples by solid-phase microextraction coupled to liquid chromatography

Solid-phase microextraction (SPME) coupled to LC for the analysis of five diphenylether herbicides (aclonifen, bifenox, fluoroglycofen-ethyl, oxyfluorfen, and lactofen) is described. Various parameters of extraction of analytes onto the fiber (such as type of fiber, extraction time and temperature, pH, impact of salt and organic solute) and desorption from the fiber in the desorption chamber prior to separation (such as type and composition of desorption solvent, desorption mode, soaking time, and flush-out time) were studied and optimized. Four commercially available SPME fibers were studied. PDMS/divinylbenzene (PDMS/DVB, 60 microm) and carbowax/ templated resin (CW/TPR, 50 microm) fibers were selected due to better extraction efficiencies. Repeatability (RSD, < 7%), correlation coefficient (> 0.994), and detection limit (0.33-1.74 and 0.22-1.94 ng/mL, respectively, for PDMS/DVB and CW/TPR) were investigated. Relative recovery (81-104% for PDMS/DVB and 83-100% for CW/TPR fiber) values have also been calculated. The developed method was successfully applied to the analysis of river water and water collected from a vegetable garden.     

Use of solid-phase microextraction to detect and quantify gas-phase dicarbonyls in indoor environments

Solid-phase microextraction (SPME) was evaluated for the detection and quantification of the gas-phase dicarbonyls, glyoxal (GLY) and methylglyoxal (MGLY). Additionally, polydimethylsiloxane (PDMS), polydimethylsiloxane/divinylbenzene (PDMS/DVB), and carbowax/divinylbenzene (CW/DVB) fibers were tested to determine the optimum fiber for detection of these species. GLY and MGLY were derivatized with O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine hydrochloride (PFBHA), extracted with SPME from headspace or bag chamber and then analyzed by GC/MS. The PDMS/DVB SPME fiber for on-fiber derivatization and subsequent sampling for gas-phase methylglyoxal provided the optimum combination of analytical reproducibility and sensitivity. Linearity of the calibration curve was achieved across a range of 11-222 microg/m(3) (4-75 ppb).     

Surface energy characteristics of toner particles by automated inverse gas chromatography

This study develops a method for the analysis of biocides Irgarol 1051 and Sea Nine 211 in environmental water samples, using solid-phase microextraction (SPME). Their determination was carried out using gas chromatography with flame thermionic (FTD), electron-capture (ECD) and mass spectrometric detection. The main parameters affecting the SPME process such as adsorption-time profile, salt additives and memory effect were studied for five polymeric coatings commercially available for solid-phase microextraction: poly(dimethylsiloxane) (100 and 30 microm), polyacrylate, poly(dimethylsiloxane)-divinylbenzene (PDMS-DVB 65 microm) and Carbowax-divinylbenzene (65 microm). The method was developed using spiked natural waters such as tap, river, sea and lake water in a concentration range of 0.5-50 microg/l. All the tested fiber coatings have been evaluated with regard to sensitivity, linear range, precision and limits of detection. Typical RSD values (triplicate analysis) in the range of 3-10% were obtained depending on the fiber coating and the compound investigated. The recoveries of biocides were in relatively high levels 60-118% and the calibration curves were reproducible and linear (R2>0.990) for both analytes. The SPME partition coefficients (Kf) of both compounds were also calculated experimentally in the proposed conditions for all fibers using direct sampling. Finally the influence of organic matter such as humic acids on extraction efficiency was studied, affecting mostly Sea Nine 211 uptake by the fiber. Optimum analytical SPME performance was achieved using the PDMS-DVB 65 microm fiber coating in ECD and FTD systems for Sea Nine 211 and Irgarol 1051, respectively.     

Comparison of simultaneous distillation extraction and solid-phase microextraction for the determination of volatile flavor components

Traditional simultaneous distillation extraction (SDE) and solid-phase microextraction (SPME) techniques were compared for their effectiveness in the extraction of volatile flavor compounds from various mustard paste samples. Each method was used to evaluate the responses of some analytes from real samples and calibration standards in order to provide sensitivity comparisons between the two techniques. Experimental results showed traditional SDE lacked the sensitivity needed to evaluate certain flavor volatiles, such as 1,2-propanediol. Dramatic improvements in the extraction ability of the SPME fibers over the traditional SDE method were noted. Different SPME fibers were investigated to determine the selectivity of the various fibers to the different flavor compounds present in the mustard paste samples. Parameters that might affect the SPME, such as the duration of absorption and desorption, temperature of extraction, and the polarity and structure of the fiber were investigated. Of the various fibers investigated, the PDMS–DVB fiber proved to be the most desirable for these analytes.     

Preparation and application of solid-phase microextraction fiber based on molecularly imprinted polymer for determination of anabolic steroids in complicated samples

A relatively selective, chemically and physically robust SPME fiber was developed in a simple way with testosterone-imprinted polymer, and then directly coupled with gas chromatography-mass spectrometry (GC-MS) for selective extraction and analysis of anabolic steroids. The factors influencing polymerization (i.e., cross-linker, polymerization solvent, polymerization time) were optimized in detail and the polymer was characterized by scanning electron microscope, infrared spectrometer and thermogravimetric analyzer. Furthermore, the extraction performance of the MIP-coated SPME fibers such as extraction ability and selectivity was evaluated. Moreover, the interaction mode between target analytes and fiber coating was deducted. Finally, the method for extraction and determination of androsterone, stanolone, androstenedione and methyltestosterone by the homemade MIP-coated SPME fibers with GC-MS was obtained. It was applied to the simultaneous analysis of four anabolic steroids in the spiked human urine with the satisfactory recoveries.     

Determination of poly(dimethyl)siloxane-water partition coefficients for selected hydrophobic organic chemicals using 14C-labeled analogs

Aqueous solutions of (14)C-labeled analogs of seven hydrophobic organic chemicals (HOCs) were subject to solid-phase microextraction (SPME) under static conditions to assess their multi-compartment distribution and to compare poly(dimethyl)siloxane (PDMS)-water partition coefficients (K(f) values) with previously reported values. To accomplish this, a protocol for quantitative desorption of radiolabelled HOCs from SPME fibers using hexane was developed. Time series extractions indicated that loading of SPME fibers had reached steady-state by day 8 for PCBs 52, 77 and 153, phenanthrene, benzo[a]pyrene, p,p'-DDT and p,p'-DDE. The recovery of spiked radioactivity among the (residual) aqueous phase, the PDMS coating, and all remaining wetted experimental surfaces ranged between 80 and 120%. K(f) values based on (14)C-labeled analogs were in good agreement with previously published values that were determined at (or closely approaching) equilibrium conditions and without significant chemical depletion and/or uncorrected system losses. Because it allows for the direct determination of HOCs associated with the residual aqueous and experimental surface compartments, the use of radiolabelled HOC analogs is a powerful tool in discriminating among competing sorptive compartments encountered in most SPME fiber calibration methodologies employed to date.     

Development of a sensitive methodology for the analysis of chlorobenzenes in air by combination of solid-phase extraction and headspace solid-phase microextraction

In this study, a combination of solid-phase extraction (SPE) and solid-phase microextraction (SPME) has been used to determine chlorobenzenes in air. Analytes were sampled by pumping a known volume of air through a porous polymer (Tenax TA). Then, the adsorbent was transferred into a glass vial and SPME was performed. The quantification was carried out using gas chromatography (GC)-electron-capture detection or GC-MS. Several SPME coatings (100 microm poly(dimethylsiloxane) (PDMS), 75 microm Carboxen (CAR)-PDMS, 65 microm PDMS-divinylbenzene (DVB), 65 microm PDMS-DVB and 85 microm polyacrylate (PA) were evaluated, obtaining the highest responses with Carbowax (CW)- PDMS for the most volatile chlorobenzenes, and with PDMS-DVB or CW-DVB fibers for the semivolatile compounds. To optimize some other factors that could affect the SPME step, a factorial design was used. Kinetic studies of the SPME process were also performed. Concerning the SPE step, breakthrough was studied, showing that 2.5 m3 of air could be processed without losses of the most volatile compounds. The performance of the method was evaluated. External calibration, which does not require the complete sampling process, demonstrated to be suitable, obtaining good linearity (R2 > 0.99) for all chlorobenzenes. Recovery studies were performed at two concentration levels (4 and 40 ng/m3), obtaining quantitative recoveries (>80%). Limits of detection at the sub ng/m3 were achieved for all the target compounds.     

Development of a solid-phase microextraction method for the analysis of phenolic flame retardants in water samples

A solid-phase microextraction (SPME) method for the ultra-trace determination of brominated phenols in aqueous samples has been developed and is reported for the first time to the best of our knowledge. 3,5,3',5'-tetrabromobisphenol A (TBBPA), the most widely used brominated flame retardant, and other phenolic flame retardants in commercial use, such as 2,4-dibromophenol (2,4-DBP), 2,4,6-tribromophenol (TBP) and pentabromophenol (PBP) have been included as target analytes. The analytical procedure involves the in situ acetylation-SPME and gas chromatography-mass spectrometry (GC-MS) determination of the target analytes. A multi-factor categorical experimental design was created to study the main parameters affecting the extraction efficiency, allowing also the evaluation of interaction effects between factors. The factors studied were type of fiber, extraction mode, exposing the fiber directly into the sample (DSPME) or into the headspace over the sample (HSSPME), and extraction temperature. Carboxen-polydimethylsiloxane (CAR-PDMS) fiber appeared to be the most suitable of the five fibers tested for the extraction of most compounds, excluding PBP and TBBPA for which polydimethylsiloxane (PDMS) was the most efficient coating. The highest response was achieved for both fibers sampling in headspace mode at 100 degrees C. In order to test the linearity of the method, calibration studies were performed with both CAR-PDMS and PDMS coatings. For both fibers, the method was linear in a range of 2 orders of magnitude, giving relative standard deviation (RSD%) below 10% for most compounds and detection limits at the low pg/mL level. In addition, the feasibility of the method for simultaneous determination of chlorinated and brominated phenols was studied. Finally, the method was applied to several real samples including tap water and effluent and influent waste water samples from an urban treatment plant, in which several phenolic compounds, such as phenol, methylphenols and chlorophenols, could be detected and quantified.     

Comparative study of the sol–gel based solid phase microextraction fibers in extraction of naphthalene, fluorene, anthracene and phenanthrene from saffron samples extractants

We are introducing a method for the determination of some polycyclic aromatic hydrocarbons in aqueous saffron sample by direct immersion solid phase microextraction (SPME) and gas chromatography. A sol–gel technique is used for the preparation of the SPME fibers. Three kinds of sol–gel coatings on the fibers were tested and compared. They are composed of poly(dimethyl siloxane) (PDMS), poly(ethylene glycol) (PEG), and a poly(ethylene glycol) modified with multi-walled carbon nanotubes (PEG/CNTs). The effects of fiber coating, desorption time, desorption temperature, extraction time, stirring speed and salting effect were optimized. Under the optimal conditions, the detection limits (at S/N?=?3) are 7–50, 5–50, and 1–10?pg?mL^–1, respectively, for SPME fibers made from PDMS, PEG and PEG/CNTs. The relative standard deviations for one type of fiber are from 2.1% to 9.6% for all fibers (at n?=?5), and in the range from 1.9% to 9.8% from batch to batch (for n?=?3).

Considerations on Static and Dynamic Sorptive and Adsorptive Sampling to Monitor Volatiles Emitted by Living Plants

Static and dynamic headspace sampling have been applied for the enrichment of volatiles emitted by living plants. For solid phase microextraction (SPME) the sorptive fibers polydimethylsiloxane (PDMS) and polyacrylate (PA) have been compared and, in accordance with the like‐like principle, polar compounds exhibit more affinity for the PA fiber while apolar solutes favor the PDMS fiber. For dynamic sampling, tubes packed with PDMS particles show greater inertness than Tenax; some Tenax decomposition products, e.g. benzaldehyde and acetophenone, interfere with the analyses. With PDMS particles operated in the breakthrough mode, the obtained profiles are similar to those obtained by SPME on the PA fiber. Recoveries relative to a packed PDMS bed are 85% for Tenax, 2.4% for SPME‐PDMS, and 6.2% for SPME‐PA.     

Rapid screening of precursor and degradation products of chemical warfare agents in soil by solid-phase microextraction ion mobility spectrometry (SPME-IMS)

The use of solid-phase microextraction (SPME) coupled to ion mobility spectrometry (IMS) to detect precursor and degradation products of chemical warfare agents (CWAs) as soil contaminants was investigated. The development and characterization of a system to interface a thermal desorption solid-phase microextraction inlet with a hand held ion mobility spectrometer was demonstrated. The analytes used in this study were diisopropyl methylphosphonate (DIMP), diethyl methylphosphonate (DEMP), and dimethyl methylphosphonate (DMMP). Two SPME fibers with different stationary phases, 100 μm polydimethylsiloxane (PDMS) and 65 μm polydimethylsiloxane divinylbenzene (PDMS/DVB), were evaluated in this study to determine the optimal fiber and extraction conditions. Better results were obtained with the PDMS fiber. SPME-IMS offered good repeatability and detection of the precursor and degradation products in spiked soil at concentrations as low as 10 μg/g. Sample analysis time was less than 30 min for all the precursor and degradation products.     

Application of solid-phase microextraction for determination of pyrethroids in groundwater using liquid chromatography with post-column photochemically induced fluorimetry derivatization and fluorescence detection

Solid-phase microextraction (SPME) is a rapid and simple analytical technique which uses coated fused-silica fibers to extract analytes from aqueous samples. This study develops a method of SPME analysis for seven pyrethroids, including fenpropathrin, lambda-cyhalothrin, deltamethrin, fenvalerate, permethrin, tau-fluvalinate and bifenthrin in groundwater samples using high performance liquid chromatography combined with post-column photochemically induced fluorimetry derivatization and fluorescence detection (SPME-LC-PIF-FD). To perform the SPME, a 60 microm polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber was used for the extraction of the pesticides from groundwater samples. The main factors affecting the SPME process, such as extraction time, stirring rate, extraction temperature, pH and the desorption process were studied. The use of photochemically induced fluorescence for detection improved sensitivity and selectivity. The limits of quantification (LOQs) obtained in the matrix, with respect to EURACHEM Guidance, varied between 0.03 and 0.075 microgL(-1). Relative recoveries ranged from 92 to 109% and relative standard deviations values ranged from 2 to 9%.     

Solid-phase microextraction for determining the distribution of sixteen US Environmental Protection Agency polycyclic aromatic hydrocarbons in water samples

A solid-phase microextraction (SPME) procedure has been developed for the determination of 16 US Environmental Protection Agency promulgated polycyclic aromatic hydrocarbons (PAHs). Five kinds of SPME fibers were used and compared in this study. The extracted sample was analyzed by gas chromatography with flame ionization detection or mass spectrometry. Parameters affecting the sorption of analyte into the fibers, including sampling time, thickness of the fiber coating, and the effect of temperature, have been examined. Moreover, the feasibility of headspace SPME with different working temperatures was evaluated. The method was also applied to real samples. The 85-microm polyacrylate (PA) and 100-microm poly(dimethylsiloxane) (PDMS) fibers were shown to have the highest affinities for the selected PAHs. The PA fiber was more suitable than the PDMS fiber for the determination of low-ring PAHs while high sensitivity of high-ring PAHs was observed when a 100-microm PDMS fiber was used. The method showed good linearity between 0.1 and 100 ng/ml with regression coefficients ranging from 0.94 to 0.999. The reproducibility of the measurements between fibers was found to be very good. The precisions of PA and PDMS fibers were from 3 to 24% and from 3 to 14%, respectively. Headspace SPME is a valid alternative for the determination of two- to five-ring PAHs. A working temperature of 60 degrees C provides significant enhancement in sensitivity of two- to five-ring PAHs having low vapor pressures (>10(-6) mmHg at 25 degrees C) (1 mmHg = 133.3 Pa) and low Henry's constants (>10 atm ml/mol) (1 atm = 1.01 x 10(5) Pa).     

Monitoring the emission of volatile organic compounds from flowers of Jasminum sambac using solid-phase micro-extraction fibers and gas chromatography with mass spectrometry detection

Solid-phase micro-extraction (SPME) was studied as a solvent free alternative method for the extraction and characterization of volatile compounds in intact and plucked flowers of Jasminum sambac at different day time intervals using gas chromatography (GC-FID) and gas chromatography-quadrupole mass spectrometry. The analytes identified included alcohols, esters, phenolic compounds, and terpenoids. The main constituents identified in the flower aroma using different fibers were cis-3-hexenyl acetate, (E)-beta-ocimene, linalool, benzyl acetate, and (E,E)-alpha-farnesene. The benzyl acetate proportion decreased from morning to afternoon and then increased in evening collections. PDMS fiber showed a high proportion of (E,E)-alpha-farnesene in jasmine floral aroma. Among other constituents identified, cis-3-hexenyl acetate, linalool, and benzyl acetate were major aroma contributors in plucked and living flowers extracts using PDMS/DVB, Carboxen/PDMS, and DVB/Carboxen/PDMS fibers. PDMS/DVB recorded the highest emission for benzyl acetate while the (E)-beta-ocimene proportion was highest in DVB/Carboxen/PDMS when compared with the rest. The highest linalool content, with increasing proportion from morning to noon, was found using mixed coating fibers. Almost negligible volatile adsorption was recorded for the polyacrylate fiber for intact flower aroma, whereas it was most effective for benzyl acetate, followed by indole under plucked conditions. Moreover, the highest amounts extracted, evaluated from the sum of peak areas, were achieved using Carboxen/PDMS, and DVB/Carboxen/PDMS. Introduction of a rapid, and solvent free SPME method for the analysis of multicomponent volatiles can be successfully employed to monitor the extraction and characterization of flower aroma constituents.