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A new and green development in the field of food packaging is the use of colorimetric films containing anthocyanins, which not only can respond to food spoilage but also have no environmental risk and help the environment full of unacceptable and polluted substances created by humans. In this research, a completely natural film (GCNG) was made using natural materials including tragacanth gummifer (G), chitosan nanoparticles (C), and an extract containing anthocyanins of a type of wild grape called Sardasht black (G) with Alumina nanoparticles (N) for use in food packaging. This biodegradable film (GCNG) presented relatively wide color differences from red to blue in different buffer solutions (pH 2-12), which was clearly observed by the naked eye. Sardasht black grape extract contains large amounts of anthocyanins and antioxidants that can be extracted and used in the preparation of packaging films. The properties of prepared films, including mechanical properties, permeability to water vapor, solubility, swelling, as well as antimicrobial properties were checked by measuring the diameter of the diffusion area by agar disk test. GCNG films showed strong antioxidant activity and good antibacterial activity against E. coli and S. aureus. The results suggested this film has promising potential as an active and smart packaging material for applications in the food industry.

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The present study was conducted to synthesise a carbon nanotube/layered double hydroxide nanocomposite by an in situ growth route via electrostatic force. The fabricated carbon nanotube/layered double hydroxide nanocomposite was successful in deposition on a stainless-steel wire for the preparation of the solid-phase microextraction fibre. The produced fibers are enduring with high suitability being chemically and thermally stable capable of coupling to GC and GC/MS. The important extraction parameters including extraction temperature, extraction time, sample mass and added water were simultaneously optimised using an optimisation approach. I comparison to hydrodistillation (HD), headspace single drop micro-extraction) HS-SPME (is advantageous regarding little sample level, time-efficiency, convenience and low cost.

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INTRODUCTION: A new solid-phase microextraction fibre is fabricated through polymerisation of molecularly imprinted polymer on the surface of a layered double hydroxide framework that has been fabricated via the in situ synthesis on a non-porous anodic aluminium oxide/aluminium wire as both the substrate and the aluminium source. OBJECTIVE: The synthesized SPME fiber was performed to analyze trace digoxin in real samples. MATERIAL AND METHOD: A one-at-a-time optimization strategy was applied for optimizing the important extraction parameters such as extraction solvent, extraction time, stirring rate, pH, ionic strength, and desorption time. RESULT: Aluminum surface before and after anodizing and LDH structure reveal that anodizing and preparation LDH increases the surface area and adsorption capacity of aluminum wire. CONCLUSION: Under optimum conditions, the repeatability for one fibre (n = 3), expressed as relative standard deviation (RSD %), was 5.2%.

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A simple microwave distillation was used in order to prevent the traditional prolonged hydrodistillation. To this end, the volatile compounds in aerial sections of Salvia hydrangea DC were analyzed. Then, headspace single drop micro-extraction (HS-SDME) was done that was connected to gas chromatography-mass spectrometry (GC-MS). Following irradiation, the volatile components of headspace were gathered through an n-heptadecane single drop. The relative peak areas, which were used as the index, optimized the conditions of extraction. The indexes of retention and mass spectra were used for confirmation of chemical configuration in the extracts of HS-SDME.

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Nanosheets of a porous layered double hydroxide were directionally arranged on boehmite nanowires and porous carbon and used as a coating for solid-phase microextraction (SPME) method. Porous carbon tubes were prepared from goat grass and then coated with layered double hydroxide nanosheets and boehmite nanowires. The nanomaterial was placed on a stainless-steel wire which then was used for the extraction of fifteen agrochemicals from aqueous sample solutions. The extraction temperature, extraction time, ionic strength, stirring rate, and desorption temperature and time were optimized. Following thermal desorption of the agrochemicals in the injector of the gas chromatograph, they were quantified by GC/MS. Under optimum conditions, the repeatability for one fiber, expressed as relative standard deviation, was between 2.9 and 11.1%. The detection limits for the agrochemicals are between 2-29 ng L-1. The method is simple, fast, and inexpensive (in terms of equipment). The fiber is thermally stable, and the relative recoveries from spiked samples are better compared to conventional methods of extraction. Graphical abstract Schematic illustration of the preparation of three-dimensional hierarchical boehmite/ layered double hydroxides/ porous carbon (Boeh/LDH/pC) SPME fibers and application for the extraction of fifteen agrochemicals from aqueous sample solutions following quantification by GC/MS.

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INTRODUCTION: Research on the volatile oil composition of Thymus kotschyanus Boiss was conducted by applying mesoporous organosilica based on alkylimidazolium ionic liquid (PMO-IL) as a fibre coating material via a method referred to as microwave-assisted headspace solid-phase microextraction (MA-HS-SPME). METHODOLOGY: This technique entails microwave irradiation of the sample and collection of the volatile sample components. These components are further introduced into a gas chromatography-mass spectrometry (GC-MS) injection port for further analysis. A simplex method was used for the optimisation of three different parameters affecting the efficiency of the extraction. CONCLUSION: The MA-HS-SPME method proved to be the most suitable technique in oil determination and extraction from Thymus kotschyanus owing to its advantageous aspects of cost effectiveness, simplicity and solvent independence.

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A nanostructured star-shaped polythiophene dendrimer was prepared and used as a fiber coating for headspace solid phase microextraction of selected triazolic pesticides (tebuconazole, hexaconazole, penconazole, diniconazole, difenoconazole, triticonazole) from water samples. The dendrimer with its large surface area was characterized by thermogravimetric analysis, UV-Vis spectroscopy and field emission scanning electron microscopy. It was placed on a stainless steel wire for use in SPME. The experimental conditions for fiber coating, extraction, stirring rate, ionic strength, pH value, desorption temperature and time were optimized. Following thermal desorption, the pesticides were quantified by GC-MS. Under optimum conditions, the repeatability (RSD) for one fiber (for n = 3) ranges from 4.3 to 5.6%. The detection limits are between 8 and 12 pg mL-1. The method is fast, inexpensive (in terms of equipment), and the fiber has high thermal stability. Graphical abstract Schematic presentation of a nanostructured star-shaped polythiophene dendrimer for use in headspace solid phase microextraction of the triazolic pesticides (tebuconazole, hexaconazole, penconazole, diniconazole, difenoconazole, triticonazole). They were then quantified by gas chromatography-mass spectrometry.

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The composition of essential oils from Stachys byzantina was studied by simple method based on gas chromatography-mass spectrophotometry (GC-MS) following microwave assisted headspace single-drop microextraction (MA-HS-SDME) method. Several parameters affecting MA-HS-SDME such as sample mass, solvent volume, extraction time, microwave power and the nature of extracting solvent were optimised. The MA-HS-SDME method was compared with traditional hydrodistillation (HD) method. Within the study elaborated, thirty-eight components were extracted and identified. Compared with HD, MA-HS-SDME is an easy, rapid and efficient method for the analysis of essential oils in S. byzantina.

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Zn/Al layered double hydroxide (LDH) films were fabricated in situ with anodic aluminium oxide aluminium as both the substrate and the sole aluminium source by means of urea hydrolysis. Headspace solid phase microextraction using LDH fibre in combination with capillary GC-MS was utilised as a monitoring technique for the collection and detection of the volatile compounds of Origanum vulgare. Experimental parameters, including the sample weight, microwave power, extraction time and humidity effect, were examined and optimised.

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In this study, the efficiency of nanoporous aluminium wires as fibres for headspace solid-phase microextraction (HS-SPME) of volatile compounds from Lippia citriodora was investigated and compared with two anodised methods. The prepared fibres are durable with very good chemical and thermal stability which can be coupled to GC and GC/MS. A one at-a-time optimisation strategy was applied for optimising the important extraction parameters such as extraction temperature, extraction time, sample mass and added water. Compared with hydrodistillation (HD), HS-SPME provide the advantages of a small amount of sample, time-saving, simplicity and cheapness.

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We have synthesized an organic-inorganic polyaniline-halloysite nanotube composite by an in situ polymerization method. This nanocomposite is immobilized on a stainless-steel wire and can be used as a fiber coating for solid-phase microextraction. It was found that our new solid-phase microextraction fiber is an excellent adsorbent for the extraction of some volatile organic compounds in aqueous samples in combination with gas chromatography and mass spectrometry. The coating can be prepared easily, is mechanically stable, and exhibits relatively high thermal stability. It is capable of extracting phenolic compounds from water samples. Following thermal desorption, the phenols were quantified by gas chromatography with mass spectrometry. The effects of extraction temperature, extraction time, sample ionic strength, stirring rate, pH, desorption temperature and desorption time were studied. Under optimal conditions, the repeatability for one fiber (n = 5), expressed as the relative standard deviation, is between 6.2 and 9.1%. The detection limits range from 0.005 to 4 ng/mL. The method offers the advantage of being simple to use, with a shorter analysis time, lower cost of equipment and higher thermal stability of the fiber in comparison to conventional methods of analysis.

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This article investigates the effect of microwaves on the amount of volatile compounds Achillea tenuifolia Lam with two methods, headspace single-drop microextraction and microwave-assisted headspace single-drop microextraction (MA-SDME), for the analysis of essential oil. Solvent selection, solvent volume, microwave power, irradiation time and sample mass were optimised by the simplex method.

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A metal-organic framework/periodic mesoporous silica (MOF-5@SBA-15) hybrid material has been prepared by using SBA-15 as a matrix. The prepared MOF-5@SBA-15 hybrid material was then deposited on a stainless-steel wire to obtain the fiber for the solid-phase microextraction of phenolic compounds. Modifications in the metal-organic framework structure have proven to improve the extraction performance of MOF/SBA-15 hybrid materials, compared to pure MOF-5 and SBA-15. Optimum conditions include an extraction temperature of 75°C, a desorption temperature of 260°C, and a salt concentration of 20% w/v. The dynamic linear range and limit of detection range from 0.1-500 and from 0.01-3.12 ng/mL, respectively. The repeatability for one fiber (n = 3), expressed as relative standard deviation, is between 4.3 and 9.6%. The method offers the advantage of being simple to use, rapid, and low cost, the thermal stability of the fiber, and high relative recovery (compared to conventional methods) represent additional attractive features.

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In this research, a carbon nanotube/layered double hydroxide nanocomposite was synthesized by an in situ growth route by electrostatic force. The prepared carbon nanotube/layered double hydroxide nanocomposite was successfully prepared and deposited on a stainless-steel wire for the fabrication of the solid-phase microextraction fiber. The fiber was evaluated for the extraction of phenolic compounds from water samples. Analytical merits of the method, under optimum conditions (extraction temperature: 75°C, extraction time: 30 min, desorption time: 2 min, desorption temperature 260°C, salt concentration: 10% w/v) are 0.01-300 ng/mL for the linear dynamic range and 0.005-0.08 for the limit of detection. In optimum conditions, the repeatability for one fiber (n = 3), expressed as relative standard deviation, was between 6.5 and 9.9% for the phenolic compounds.

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In this work, a highly porous fibre coated with polythiophene/hexagonally ordered silica nanocomposite (PT/SBA-15) was prepared and used for extraction of essential oils with microwave-assisted distillation headspace solid phase microextraction (MA-HS-SPME) method. The prepared nanomaterials were immobilised on a stainless steel wire for fabrication of the SPME fibre. Using MA-HS-SPME followed by GC-MS, 24 compounds were separated and identified in Achillea tenuifolia, which mainly included limonene (28.6%), α-cadinol (12.7%), borneol (6.7%), caryophyllene oxide (3.2%), bornyl acetate (4.3%), camphene (3.2%) and para-cymene (2.3%). The experimental results showed that the polythiophene/hexagonally ordered silica nanocomposite fibres were suitable for the semi-quantitative study of the composition of essential oils in plant materials and for monitoring the variations in the volatile components of the plants.

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In this paper, for the first time, an inorganic-organic hybrid material based on ZnO nanoparticles was anchored to a composite made from polythiophene and hexagonally ordered silica (ZnO/PT/SBA-15) for use in solid-phase fibre microextraction (SPME) of medicinal plants. A homemade SPME apparatus was used for the extraction of volatile components of Ziziphora tenuior L. A simplex method was used for optimisation of five different parameters affecting the efficiency of the extraction. The main constituents extracted by ZnO/PT/SBA-15 and PDMS fibres and hydrodistillation (HD) methods, respectively, included pulegone (51.25%, 53.64% and 56.68%), limonene (6.73%, 6.58% and 8.3%), caryophyllene oxide (5.33%, 4.31% and 4.53%) and 1,8-cineole (4.21%, 3.31% and 3.18%). In comparison with the HD method, the proposed technique could equally monitor almost all the components of the sample, in an easier way, in a shorter time and requiring a much lower amount of the sample.

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Flavonoids, anthocyanins, antioxidant capability, total phenolic, ascorbic acid contents, and essential oils compounds of Ziziphora tenuoir (Lamiaceae) for polar and non-polar subfraction in different stages of growth (pre-flowering and flowering) were evaluated in this work. Antioxidant activities of the samples were determined by three testing systems namely DPPH, ß-carotene/linoleic acid, and reducing power assay. In the DPPH system, the highest radical scavenging activity was seen by the nonpolar subfraction of the methanol extract in the flowering stage (IC50 43.17 ± 3.68 µg·mL(-1)). Large differences in the amount of phenolic compounds, antioxidant activity, anthocyanins, and flavonoids of Z. tenuoir in two stages of growth were detected. The chemical composition of the hydrodistilled essential oil of the aerial parts of Z. tenuoir was analyzed by GC/MS and compared in the two stages of growth. The main constituents of the 28 identified compounds in the oil were found to be pulegone (67.34% vs 59.61%), ß-humulene (3.24% vs 3.25%), and limonene (5.06% vs 2.57%) at the flowering and pre-flowering stages, respectively.

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Nanoporous silica was prepared and functionalized with amino propyl-triethoxysilane to be used as a highly porous fiber-coating material for solid-phase microextraction (SPME). The prepared nanomaterials were immobilized onto a stainless steel wire for fabrication of the SPME fiber. The proposed fiber was evaluated for the extraction of volatile component of Citrus aurantium L. leaves. A homemade microwave-assisted extraction followed by headspace (HS) solid-phase apparatus was used for the extraction of volatile components. For optimization of factors affecting the extraction efficiency of the volatile compounds, a simplex optimization method was used. The repeatability for one fiber (n = 4), expressed as RSD, was between 3.1 and 8.6% and the reproducibility for five prepared fibers was between 10.1 and 14.9% for the test compounds. Using microwave-assisted distillation HS-SPME followed by GC-MS, 53 compounds were separated and identified in C. aurantium L., which mainly included limonene (62.0%), linalool (7.47%), trans-ß-Ocimene (3.47%), and caryophyllene (2.05%). In comparison to a hydrodistillation method, the proposed technique could equally monitor almost all the components of the sample, in an easier way, which was rapid and required a much lower amount of sample.

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INTRODUCTION: The development of simple, rapid and solvent-free methods for the analysis of essential oils is highly desirable. Microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) is a new sampling and concentration technique for the extraction of volatile components in medicinal plants. The main advantages of this method are the reduction of extraction time and of organic solvent. OBJECTIVE: A highly porous Santa Barbara amorphous (SBA-15)/polyaniline material was prepared in order to produce a SPME fibre. The proposed fibre was evaluated for the extraction of the volatile component of Teucrium polium L. METHODOLOGY: A homemade MA-HS-SPME apparatus was used for the extraction of volatile components. Highly porous SBA-15/polyaniline materials were prepared for SPME. The prepared nanomaterial was immobilized onto a stainless steel wire for fabrication of the SPME fibre. RESULTS: The SBA-15/polyaniline nanonporous fibre could adsorb volatile components of T. polium efficiently. In comparison with a HD method, the proposed technique could equally monitor almost all the components of the sample, but in an easier way that was rapid and required a much lower amount of sample. CONCLUSION: The experimental results showed that the nanoporous fibre was suitable for the semi-quantitative study of the composition of essential oils in plant materials and monitoring the variations in the volatile components of the plants.

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This article investigates the effect of microwaves on the amount of volatile compounds from Thymus kotschyanus Boiss with four methods, headspace single-drop microextraction, microwave-assisted headspace single-drop microextraction, microwave distillation extraction and hydrodistillation, for the analysis of essential oil. Solvent selection, solvent volume, microwave power, irradiation time and sample mass were optimised by simplex method.

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