The most recent contributions on solventless extraction techniques have been reviewed. This paper deals with those techniques that use solid phases, such as solid-phase microextraction, liquid phases, such as single-drop microextraction and hollow-fibre liquid-phase microextraction, and subcritical fluids, such as subcritical water extraction. In all cases, the most recent publications have been critically studied. Direct extraction and derivatization processes to facilitate the extraction of analytes in different areas have been included. Hyphenated approaches, if available, are also included in this review. Comparison of techniques organized by analytes and matrices also enhances this critical overview of solventless techniques.

A new antioxidant active packaging material for food has been designed and developed, consisting of a polypropylene film in which some natural antioxidants have been immobilized. The antioxidant properties of the new material have been tested by using both pure myoglobin and fresh beef steaks. Two different cell configurations (glass vial and Petri dish) and four different myoglobin concentrations-according to the common content of this compound in fresh meat and meat derivatives (1080, 1995, 3332, and 4414 microg g(-1), respectively)-have been evaluated in oxidation studies. Furthermore, three different concentrations of natural antioxidants in the film (designated as PR1, PR2, and PR3) were evaluated. Once myoglobin samples and the active films were introduced in the cell, they were exposed to cool white fluorescent light to accelerate oxidation for a period of time ranging from 5 to 30 days. Remaining myoglobin concentration was measured by molecular absorption UV-vis spectrophotometry at 409 nm. Organoleptic properties and color, texture, and physical characteristics of fresh meat packaged with the new active film have also been measured to evaluate the shelf life of the packaged meat. Results showed that, compared to normal polypropylene, the active film containing natural antioxidants efficiently enhanced the stability of both myoglobin and fresh meat against oxidation processes, thus being a promising way to extend the shelf life of fresh meat.

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The determination of several compounds present in a commercial polycarbonate container intended to be used in microwave ovens which could be considered as potential migrants has been carried out by reversed-phase high-performance liquid chromatography (HPLC) with both ultraviolet (UV) and fluorescence detectors. Total dissolution with dichloromethane and polymer reprecipitation with methanol have been used to evaluate 100% potential migration as the worst case. The extract consisted of a complex mixture containing monomers, oligomers, UV stabilizers, antioxidants, degradation products, and other additives. Phenol, Bisphenol A, 2,4-di-tert-butylphenol, Cyasorb UV5411, bis(2-ethylhexylphthalate), Irganox 1076, and Irgafos 168 were identified by both retention times and fluorescence-to-UV ratios. Additional confirmation was achieved by HPLC with diode array detection and gas chromatography-mass spectrometry. Recovery percentages were in the range of 73.8-94.4%, the lowest one being for the antioxidant Irgafos 168 due to its transformation into the phosphate form and 2,4-di-tert-butylphenol. The concentrations of the studied analytes present in the polycarbonate container ranged between 0.9 and 240 microg.g(-)(1). The total dissolution conditions that may affect the final concentration of analytes, mainly Bisphenol A, are discussed.

h i g h l i g h t s " A methodology for PAH quantification from thermochemical processes was developed. " Quantification of both PAH adsorbed on soot and at the gas phase was considered. " The method gives reliable results of PAH from complex samples like soot.g r a p h i c a l a b s t r a c t . a b s t r a c tThe outlet stream from combustion processes is a complex mixture of compounds which depends on the specific operating conditions. Thermochemical processes operating under rich fuel conditions enhance the formation of polycyclic aromatic hydrocarbons (PAHs) and soot. PAH play an important role in soot formation, but they can appear adsorbed on soot surface as well as at the gas phase due to their different volatility and molecular weight. Both PAH (the gas phase and adsorbed PAH) fractions are important when considering the total characterization from pyrolytic processes, mainly for determining the emission levels of 16 Environmental Protection Agency (EPA) priority PAH. In this way, an optimized method capable to determine the aromatic compounds in the gas and particle phases in combustion exhaust gases is needed. The method here presented allows the collection and quantification of both the PAH adsorbed on soot and present at the gas phase of the exhaust gases of thermochemical processes. It involves PAH characterization by combining classical Soxhlet extraction of the sample collected, followed by an extract concentration using a rotary evaporator and subsequent micro-concentration under gentle nitrogen stream before the analysis. The EPA-PAH were determined using a gas chromatograph-mass spectrometer (GC-MS). Validation tests using a fully characterized soot, the NIST (National Institute of Standards and Technology) reference material SRM 1650b, and repeatability using diesel surrogate commercial soot named Printex-U, were done. Additionally, experiments of acetylene pyrolysis were carried out and their products analyzed for determining the PAH amount. The results showed good method 0016-2361/$ -see front matter Ó