Polyacrylate Fiber Research Articles

Determination of Residual Dimethyl Sulfate in Cephalosporin Using HS-SPME/GC-MS.

Dimethyl sulfate (DMS) is widely used in manufacturing process but because of its genotoxicity nature, it should be monitored at trace levels (1μg/mL). It is complicated and difficult to quantify DMS in cephalosporin with traditional method. Herein, a method for quantifying residual DMS in cephalosporin was developed, without complex sample preprocessing, no need for a large amount of solvent, employing headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). Compared with polydimethylsiloxane (PDMS)/divinylbenzene and polyacrylate fibers, PDMS was more suitable for absorbing DMS. The research showed that the PDMS fiber should be changed after 50 adsorption-desorption cycles. Linear regression analysis of the calibration curve demonstrated a robust linear relationship, with R2 of 0.999, across a concentration range of 0.25 to 4.0μg/mL. The method underwent rigorous validation for specificity, linearity, precision and accuracy. This method was proven effective in measuring DMS in complex matrices. The limits of detection and quantification for this method is 0.05 and 0.25μg/mL, respectively, which has room for improvement.

The Use of Ultra-Fast Gas Chromatography for Fingerprinting-Based Classification of Zweigelt and Rondo Wines with Regard to Grape Variety and Type of Malolactic Fermentation Combined with Greenness and Practicality Assessment

In food authentication, it is important to compare different analytical procedures and select the best method. The aim of this study was to determine the fingerprints of Zweigelt and Rondo wines through headspace analysis using ultra-fast gas chromatography (ultra-fast GC) and to compare the effectiveness of this approach at classifying wines based on grape variety and type of malolactic fermentation (MLF) as well as its greenness and practicality with three other chromatographic methods such as headspace solid-phase microextraction/gas chromatography-mass spectrometry with carboxen-polydimethylosiloxane fiber (SPME/GC-MS with CAR/PDMS fiber), headspace solid-phase microextraction/gas chromatography-mass spectrometry with polyacrylate fiber (SPME/GC-MS with PA fiber), and ultra performance liquid chromatography–photodiode array detector-tandem mass spectrometry (UPLC-PDA-MS/MS). Principal Component Analysis (PCA) revealed that fingerprints obtained using all four chromatographic methods were suitable for classification using machine learning (ML). Random Forest (RF) and Support Vector Machines (SVM) yielded accuracies of at least 99% in the varietal classification of Zweigelt and Rondo wines and therefore proved suitable for robust fingerprinting-based Quality Assurance/Quality Control (QA/QC) procedures. In the case of wine classification by the type of MLF, the classifiers performed slightly worse, with the poorest accuracy of 91% for SVM and SPME/GC-MS with CAR/PDMS fiber, and no less than 93% for the other methods. Ultra-fast GC is the greenest and UPLC-PDA-MS/MS is the most practical of the four chromatographic methods.

The Characterization of Volatile Compounds of Lupin Türkiye Genotype HS-SPME/GC-MS Method

The aim of this study is to reveal the volatile and semi-volatile constituent of the local Lupinus albus L. genotype grown in Türkiye by using the HS-SPME technique. Local lupin is a legume plant with great potential due to its high seed yield and protein and oil content in the seeds. Powdered seeds of local lupin genotypes were analysed and compared with respect to types and contents of volatile semi-volatile compounds contents using four different SPME fiber with GC-MS system in W9N11, SWGDR4G4 and SWGDR4G5 libraries. Fiber with 50/30 µm DVB/CAR/PDMS identified 54 compounds, 65 µm PDMS/DVB fiber 97 compounds, 85 µm Carboxen/PDMS fiber 28 compounds, and 85 µm polyacrylate 12 compounds. As a result, 65 µm PDMS/DVB fiber is the most preferable in terms of compound identification, with 97 compound. In terms of content, Benzene, Methyl(1-Methylethyl) (39.92%), Gamma-Terpinene (12.26%), Cis-Ocimene (5.93%), 1,3,6-Octatriene,3,7-Dimethyl-(% 5.51), Beta-Myrcene (4.70%), Alpha-Pinene (4.39%), Alpha.-Thujene (4.21%), Alpha Terpinene (2.55%), Camphene (2.23%), 1,6-Octadien-3-Ol,3,7-Dimethyl (2.10%) were mostly detected in the analysis with 50/30 µm DVB/CAR/PDMS fiber. With the other fiber 65 µm PDMS/DVB; phospine oxide, triphenyl- (15.49 %), pulegone (5.03 %), L-linalool (3.85 %), cyclopentasiloxane, decamethyl (3.54 %), cyclohexasiloxane, dodecamethyl (3.13 %), cyclotrisiloxane, hexamethyl (2.32 %), oxime-,methoxy-phenyl (2.08 %), 1-pentanamine,N-pentyl (1.60 %), 3,5-octadıen-2-one (1.55 %), I-menthone (1.50 %). Fiber 85 µm Carboxen/PDMS; the most four components in the content are; Benzene, 2, 4-diisocyanato-1-methyl (54.27 %), Pyrrole-3-carbonitrile, 5-formyl-2, 4 (18.41 %), 1-Butanol, 4-(1-methylethoxy) (14.67 %), pyridine,4-(1-pyrrolidinyl)- (8.13 %). With 85 µm polyacrylate fibre the most found component is 1, 2-Benzenedicarboxylic acid, diethyl ester (98.90 %). In conclusion, as far as we know this study is the first study about the volatile content of local lupin genotype of Türkiye.

Microplastic ingestion in key fish species of food webs in the Southwest Atlantic (Marine Protected Area Namuncurá / Burdwood Bank)

Microplastics (MPs) are currently one of the main problems of marine pollution, being found in all environmental matrices. Due to their size, they can be ingested by organisms directly (from the environment) or indirectly (with their prey). The objective of this study was to analyze the occurrence, abundance, concentration, and chemical nature of MPs present in the gastrointestinal tract of two fish species, Patagonotothen guntheri and Patagonotothen ramsayi, both of which are key in the food web of the Marine Protected Area Namuncurá/ Banco Burdwood (MPA N/BB). The analyzed species presented high values of MPs per individual (MPs/ind.) and occurrence compared to other studies. P. guntheri tended to have a lower number of MPs/ind. and occurrence than P. ramsayi (P. guntheri: 2.50 ± 1.93 MPs/ind., 82.50 %; P. ramsayi: 3.93 ± 2.91 MPs/ind., 90.60 %). While fibers were the predominant MPs in both species, P. ramsayi had a greater number of fragments and a greater variety of MPs chemical composition than P. guntheri. The prevailing chemical composition was cellulosic material (cellulose and cellulose mixed with polyamide and polyester). Synthetic fibers and fragments such as polyester (PET), alkyd resin, polyurethane, polyethylene, polyacrylic fiber and poly(ethylene-co-vinyl acetate-co-vinyl chloride) were also found. Although both species have a generalist diet, the differences found may be due to the fact that P. guntheri has benthopelagic feeding habits while P. ramsayi has demersal-benthic. Our study is the first report on the presence and characterization of MPs in organisms relevant to food webs in the Southwest Atlantic.

Easy determination of benzophenone and its derivatives in sunscreen samples by direct-immersion solid-phase microextraction and gas chromatography–mass spectrometry

Benzophenones (BPs) absorb different sun radiation wavelengths, making them effective UVA and UVB filters, widely used in industry. In Europe, sunscreen products contain regulated amounts (6 % w/w) of benzophenone-3 (BP-3), usually combined with other filters like octocrylene. BPs are mutagens in UV radiation, and octocrylene may degrade into BPs, making their monitoring crucial. The present manuscript proposed a novel procedure based on liquid-liquid extraction followed by direct-immersion solid-phase microextraction (LLE-DI-SPME) to isolate and determine 10 BPs in sunscreen lotions with potential results. Parameters like extraction solvent, pH, adsorption, desorption time, stirring, sating effect, and presence of organic solvents were optimized and compared with different SPME fibers, being polyacrylate (PA) fiber the most effective. Detection and quantification were performed by gas chromatography–mass-spectrometry. Analytical parameters as limits of detection were 0.05–0.10 µg kg-1, while the linear range was 0.16 up to 2000 µg kg-1. In terms of recovery, the method ranged from 83 % to 103 %; the precision of the method was good in terms of relative standard deviation (RSD) from 3.2 % to 18.7 % and without a remarkable matrix effect (–15.06–8.45 %). Despite the complexity of the samples and the difficulty posed by the DI-SPME technique, the method proved robust. The proposed method successfully detected 10 BPs in 6 different sunscreen lotions. The total presence of BPs in sunscreens ranged from 165 to 931 mg kg-1, with BP-3 detected in all samples from 4.2 to 740 mg kg-1.

Comparison of host cell protein removal by depth filters with diatomaceous earth and synthetic silica filter aids using model proteins.

A number of studies have demonstrated that depth filtration can provide significant adsorptive removal of host cell proteins (HCP), but there is still considerable uncertainty regarding the underlying factors controlling HCP binding. This study compared the binding characteristics of two fine grade depth filters, the X0SP (polyacrylic fiber with a synthetic silica filter aid) and X0HC (cellulose fibers with diatomaceous earth (DE) as a filter aid), using a series of model proteins with well-defined physical characteristics. Protein binding to the X0SP filter was dominated by electrostatic interactions with greatest capacity for positively-charged proteins. In contrast, the X0HC filter showed greater binding of more hydrophobic proteins although electrostatic interactions also played a role. In addition, ovotransferrin showed unusually high binding capacity to the X0HC, likely due to interactions with metals in the DE. Scanning Electron Microscopy with Energy Dispersive Spectroscopy was used to obtain additional understanding of the binding behavior. These results provide important insights into the physical phenomena governing HCP binding to both fully synthetic and natural (cellulose + DE) depth filters.

A Facile and in situ Preparation Technique for Solid-Phase Microextraction Fibers with MOFs Coating

In this study, a facile preparation technique for in situ growth of MOFs-based-coated solid-phase microextraction (SPME) fibers is proposed. NH2-MIL-53 can be grown on the Al wire simply by immersing the Al wire in the solution of growth seeds and metal–organic frameworks (MOFs) successively, thereby obtaining the SPME fiber. The as-prepared fiber was combined with gas chromatography flame ionization detection (GC-FID) for the determination of non-steroidal anti-inflammatory drugs (NSAIDs) in water samples. Compared with NH2-MIL-53-coated fiber prepared with the gluing method, MIL-53-coated fiber prepared by in situ self-growth and commercial polyacrylate (PA) fiber, the as-prepared fiber demonstrated the better extraction performance, owing to more exposed adsorption sites and stronger interactions with the target. Moreover, the fiber exhibited a long service life due to multifaceted stability. After optimization of extraction and desorption conditions, the analytical method had a low-detection limit (0.002–0.05[Formula: see text][Formula: see text]g[Formula: see text]L[Formula: see text], a wide linear range (0.01–500[Formula: see text][Formula: see text]g[Formula: see text]L[Formula: see text] and good reproducibility (relative standard deviation [Formula: see text]5.84%) and provided good results for actual water samples. MOFs-based SPME fibers grown on metal wires using a facile in situ technique can maximize the extraction advantage of MOFs coating, which well promotes the application and development of MOFs in solid-phase microextraction technology.

Freely dissolved concentration profile and Hyalella azteca toxicity of cationic surfactant C12-benzalkonium in spiked-sediment toxicity test

The freely dissolved concentrations (Cfree) have been considered a useful metric for exposure of aquatic organisms to organic contaminants. However, Cfree for cationic surfactants has rarely been measured, and its use in sediment toxicity tests has not been evaluated. In this study, Cfree of the cationic surfactant benzyldodecyldimethylammonium (C12-benzalkonium; C12-BAC) in water-only and spiked-sediment toxicity tests with the amphipod Hyalella azteca was analyzed using a passive sampling method. Polyacrylate-coated glass fibers were adopted as the passive sampler. Sorption isotherms of C12-BAC to the polyacrylate fibers were measured in chemical conditions comparable to those of the toxicity tests and used for Cfree calculation in both tests. Detailed concentration analysis in the sediment toxicity test demonstrated a high concentration gradient of C12-BAC between sediment and overlying water; Cfree in pore water was 17–78 times higher than Cfree in overlying water and was 7.2–13 times higher than Cfree at the sediment–water interface. The 50 % lethal concentration and bioconcentration factor of H. azteca obtained in the water-only test (23 μg/L and 140 ± 70 L/kg-wet, respectively) agreed with those calculated based on Cfree in pore water in the sediment test (49 μg/L and 140 ± 90 L/kg-wet, respectively), indicating that H. azteca is exposed mainly to the freely dissolved fraction in pore water. We concluded that Cfree in pore water is a useful exposure metric for H. azteca to cationic surfactants.

Magnetic field and microstructural effects on the electrical capacitance and resistance of a quadrupolar electrical capacitor based on cotton fabrics and carbonyl iron microparticles

In this work we present a procedure for manufacturing an electrical device in the form of a quadrupolar electrical capacitor (QEC). The device is based on cotton fiber fabrics with carbonyl iron (CI) microparticles and self-adhesive copper foil, and surgical tape in the form of polyacrylic fiber fabrics, as element of consolidation and electrical insulation. By using an RLC electrical bridge, the equivalent electrical capacitance (C) and resistance (R) at the two gates of the QEC are measured as a function of magnetic flux density B. It is shown that both C and R have different values at the two gates and are sensitively influenced by the magnetic field. When , the electrical response function at the two gates has a resistive character due to magnetostriction of CI microparticles in the QEC body. For fixed voltages at one of the gates, B-dependent voltages are measured at the other gate. The structure at the two gates are quantified in terms of fractal parameters obtained from scanning electron microscopy images. The obtained characteristics shows that the obtained QEC can be used as a magnetic controllable resistor or as a magnetic field sensor for patients wearing pacemakers.

Chemical Approach to the Optimization of Conditions Using HS-SPME/GC-MS for Characterization of Volatile Compounds in Eugenia brasiliensis Fruit.

Grumixama (Eugenia brasiliensis Lam.) is a native fruit of the Brazilian Atlantic Forest, belonging to the Myrtaceae family, which designatesthe most significant number of species with food potential. It stands out due to its phytochemical characteristics because of the presence of polyphenols and volatile organic compounds. Volatile compounds are substances released by foods that give off an aroma and influence flavor. Solid-phase microextraction is a technique that allows for low-cost, fast, and solvent-free extraction, has an affinity for numerous analytes, and is easily coupled to gas chromatography. The objectives of this work were to evaluate the efficiency of different fibers of SPME (solid-phase microextraction) in the extraction of volatile organic compounds from grumixama pulp; optimize a method for extraction time, temperature, and sample weight; and to determine the characteristic volatile profile of this fruit. For the extraction of volatile compounds, three fibers of different polarities were used: polar polyacrylate (PA) fibers, divinylbenzene/carboxyne/polydimethylsiloxane (DVB/CAR/PDMS) semipolar fibers, and polydimethylsiloxane/divinylbenzene (PDMS/DVB). Fourteen volatile organic compounds (VOCs) were identified by DVB/CAR/PDMS, six by PA, and seven by PDMS/DVB through solid-phase microextraction in the headspace mode (SPME-HS). Considering the total number of compounds identified, regardless of the fiber used, and the optimization of the method, Eugenia brasiliensis presented sesquiterpene fractions (85.7%, 83.3%, and 85.7% of total VOCs) higher than the monoterpene fractions (14.3%, 16.7%, and 14.3%) for DVB/CAR/PDMS, PA, and PDMS/DVB, respectively in its composition. In addition, it was possible to verify that the fiber DVB/CAR/PDMS presented a better efficiency due to the larger chromatographic area observed when the grumixama pulp was subjected to conditions of 75 °C, 2.0 g, and an adsorption time of 20 min.

First evidence of microplastics isolated in European citizens’ lower airway

Microplastics (MPs) have been detected in all environmental locations, including the atmosphere. However, few studies have investigated the presence of airborne MPs in the human respiratory system. Our research purpose was to investigate these pollutants in the lower human airways of 44 adult European citizens, using bronchoalveolar lavage fluid (BALF) collection as a minimally invasive method, that enables the detection of these pollutants in living patients. We studied the relationship between the patients’ life habits and physiological parameters, based on background information and medical and occupational history, and the concentration of MPs isolated from their respiratory systems. Our results indicate that most MPs were in the form of microfibers (MFs) (97.06%), with an average concentration of 9.18 ± 2.45 items/100 mL BALF, and only 5.88% (0.57 ± 0.27 items/100 mL BALF) were particulate MPs, without a significant relationship with environmental, physiological, or clinical factors. The average size was 1.73 ± 0.15 mm, with the longest dimension (9.96 mm) corresponding to a polyacrylic fiber. Taken together, the results demonstrated the occurrence of MPs in the lower human airway, although more studies are necessary to elucidate the negative effects these pollutants could induce in the human respiratory system and its associated diseases.

Hemostasis Evaluation of Antibacterial and Highly Absorbent Composite Wound Dressings in Animal Hemostasis Models.

To reduce the bleeding time and to shorten the surgery time are vital to patients’ prog-nosis, therefore, in this study, high moisture absorption nonwoven composites are proposed to attain hemostasis in time. Polyacrylate fiber and Tencel® fibers at different blending ratios (10:90, 20:80, 30:70, 40:60, and 50:50) are used to form PT composite nonwoven. Next, composed of a 50:50 ratio, PT composite nonwoven exhibits the maximal vertical wicking height of 4.4 cm along the cross direction. Additionally, the UV-Vis absorption spectra analysis shows that at absorption waves of 413–415 nm, the occurring of distinct peaks suggests the presence of nanoparticles. The XRD patterns indicate the presence of silver nanoparticles with corresponding crystal planes of characteristic peaks at (111), (200), and (220). Polyacrylate/Tencel® nonwoven composites exhibit comparable adsorption capacity of blood and water molecules. In particular, 30PT composite nonwoven outperforms the control group, exhibiting 3.8 times and 4.7 times greater the water absorption and blood absorption, respectively. Moreover, a great number of red blood cells with a size of 4–6 μm agglomerate among fibers as observed in SEM images, while 6hr-PT composite dressing demonstrates the optimal antibacterial efficacy against Escherichia coli and Staphylococcus aureus, proven by the zone of inhibition being 1.9 mm and 0.8 mm separately. When in contact with plasma, hemostasis composites have plasma hemostasis prothrombin time of 97.9%, and activated partial thromboplastin time of 96.7%. As for animal hemostasis model, the arteria over the rats’ thigh bones is cut open perpendicularly, generating mass arteria hemorrhage. To attain hemostasis, it takes 46.5% shorter time when using composite dressings (experimental group) than the control group.

Determination of particulate polycyclic aromatic hydrocarbons in ambient air by gas chromatography-mass spectrometry after molecularly imprinted polymer extraction

A solid phase extraction procedure (SPE) is described for the quantitative analysis of polycyclic aromatic hydrocarbons (PAHs) in atmospheric particulate matter (PM), as ubiquitous environmental pollutants routinely measured in air quality monitoring. A SPE cartridge was used based on a molecular imprinted polymer (MIP-SPE) properly tailored for selective retention of PAHs with 4 and more benzene fused rings. The performance of the clean-up procedure was evaluated with the specific concern of selective purification towards saturated hydrocarbons, which are the PM components mostly interfering GC analysis of target PAHs. Under optimized operative conditions, the MIP-SPE provided analyte recovery close to 95% for heavier PAHs, from benzo(α)pyrene to benzo(ghi)perylene, and close to 90% for four benzene rings PAHs, with good reproducibility (RSDs: 2.5%-5.9%). Otherwise, C17-C32n-alkanes were nearly completely removed. The proposed method was critically compared with Solid Phase Micro Extraction (SPME) using a polyacrylate fiber. Both methods were successfully applied to the analysis of ambient PM2.5 samples collected at an urban polluted site. Between the two procedures, the MIP-SPE provided the highest recovery (R% ≥ 93%) for PAHs with 5 and more benzene rings, but lower for lighter PAHs. In contrast, SPME showed a mean acceptable R% value (∼ 80%) for all the investigated PAHs, except for the heaviest PAHs in the most polluted samples (R%: 110%-138%), suggesting an incomplete purification from the interfering n-hydrocarbons.

Facile fabrication of novel cobalt-based carbonaceous coatings on nickel-titanium alloy fiber substrate for selective solid-phase microextraction

Fabrication of selective adsorption coatings plays a crucial role in solid-phase microextraction (SPME). Herein, new strategies were developed for the in-situ fabrication of novel cobalt-based carbonaceous coatings on the nickel-titanium alloy (NiTi) fiber substrate using ZIF-67 as a precursor and template through the chemical reaction of ZIF-67 with glucose, dopamine (DA) and melamine, respectively. The adsorption performance of the resulting coatings was evaluated using representative aromatic compounds coupled to high-performance liquid chromatography (HPLC) with ultraviolet detection (HPLC-UV). The results clearly demonstrated that the adsorption selectivity was subject to the surface elemental composition of the fiber coatings. The cobalt and nitrogen co-doped carbonaceous coating showed better adsorption selectivity for ultraviolet filters. In contrast, the cobalt-doped carbonaceous coating exhibited higher adsorption selectivity for polycyclic aromatic hydrocarbons. The fabricated fibers present higher mechanical stability and higher adsorption capability for model analytes than the commercial polydimethylsiloxane and polyacrylate fibers. These new strategies will continue to expand the NiTi fibers as versatile fiber substrates for metal-organic frameworks (MOFs)-derived coating materials with controllable nanostructures and tunable properties.

Chemical Physical Characterization and Profile of Fruit Volatile Compounds from Different Accesses of Myrciaria floribunda (H. West Ex Wild.) O. Berg through Polyacrylate Fiber.

Among the many species of native fruit of Brazil that have been little explored, there is Myrciaria floribunda (also known as rumberry, cambuizeiro, or guavaberry), a species with significant variability, which has fruits of different colors (orange, red, and purple) when ripe. The physical-chemical characteristics evaluated were fruit weight (FW), seed weight (SW), pulp weight (PW), number of seeds (NS), longitudinal diameter (LD), transverse diameter (TD), format (LD/TD), hydrogen potential (pH), soluble solids (SS), titratable acidity (TA), and ratio (SS/TA); further, the volatile organic compounds (VOCs) of nine accesses of rumberry orchards were identified. The averages of the variables FW, SW, PW, NS, LD, TD, shape, and firmness were 0.76 g, 0.22 g, 0.54 g, 1.45, 10.06 mm, 9.90 mm, 1.02, 2.96 N, respectively. LD/TD data showed that the fruits have a slightly rounded shape (LD/TD = 1). The averages for pH, SS, TA, and SS/TA were 3.74, 17.58 Brix, 4.31% citric acid, and 4.31, respectively. The evaluated parameters indicated that the fruits can be consumed both in natura and industrialized, with the red-colored fruits presenting a good balance of SS/TA, standards demanded by the processing industries. Thirty-six VOCs were identified, with emphasis on the sesquiterpenes. Caryophyllene (21.6% to 49.3%) and γ-selinene (11.3% to 16.3%) were the most predominant compounds in rumberry fruits.

Highly efficient solid-phase microextraction of polycyclic aromatic hydrocarbons in water based on worm-like nickel-titanium oxide nanocomposites coating grown on a nickel-titanium alloy wire by low-voltage anodization.

A novel worm-like nickel-titanium oxide nanocomposite coating was directly grown on a nickel-titanium alloy wire by low-voltage electrochemical anodization in alkaline ethylene glycol and water solution. The in situ growth of nickel-titanium oxide nanocomposites greatly depended on the volume ratio of ethylene glycol to water and temperature. Coupled to high-performance liquid chromatography with UV detection by static desorption in the mobile phase, the adsorption performance of the as-prepared fiber was evaluated for solid-phase microextraction of representative environmental analytes in water. The results indicate that the as-prepared fiber exhibits higher extraction capability for polycyclic aromatic hydrocarbons than commercial polydimethylsiloxane and polyacrylate fibers. After optimizing the extraction parameters, the calibration graphs of the developed method was linear in the range of 0.05-200 μg/L with correlation coefficients above 0.998. Limit of detection ranged from 0.013 to 0.145 μg/L for seven target analytes. Relative standard deviations of intraday and interday analyses varied from 4.0 to 5.3% and from 4.7 to 6.3% with the single fiber, respectively. The relative recoveries of 84.4-109% were achieved for highly efficient enrichment and determination of target analytes in spiked river and snow water. Moreover, the as-prepared fiber can be used more than 200 times.

Fabrication and Characterization of Moisture Slow-releasing Embroidered Electrode and ECG Monitoring Belt

The microenvironmental humidity at the interface between the bioelectrical electrode and the human skin can affect the quality of the bioelectrical signal collected by the electrode. This paper utilized superabsorbent polyacrylic fiber as the base material to fabricate a novel moisture slow-releasing embroidered electrode. The moisture-locking capacity of polyester non-woven fabric (PENWF) substrate, polyacrylic non-woven fabric (PANWF) substrate, polyester-based electrode (PE-E) and polyacrylic-based electrode (PA-E) were compared in this paper. The non-woven fabric with polyacrylic fiber owned excellent moisture-locking capacity, so it could realize the slow-releasing of moisture and provide a suitable wet environment for the dry bioelectric electrode to collect ECG signals. With the extension of time, the amplitude of the ECG signal collected by PA-E did not change much, and only decreased by 17.1 % after evaporating for 10 h; but after evaporating for 10 h, the amplitude of the ECG signal collected by the PE-E decreased by 48.9 %. In addition, 5 mm, 10 mm, and 15 mm thick polyurethane sponge (PUS) filling materials were used to make the ECG monitoring belts, and their signal-to-noise ratios were analyzed under different states of static, swinging arms and walking. The 5 mm thick elastic filler material has the highest signal-to-noise ratio among the three thicknesses. It could collect ECG signals stably under swing arm and walking at a constant speed, and the signal-to-noise ratio (SNR) were 25.393 dB and 30.086 dB respectively. The polyurethane sponge filling materials with a thickness of 5 mm provided an appropriate pre-stress for the ECG signal dynamic measurement, which could provide a reference parameter for the production of smart ECG garment in the future.

Management of venous leg ulcers with a two-layer compression bandage and a polyacrylate fibre dressing

Management of venous leg ulcers with a two-layer compression bandage and a polyacrylate fibre dressing

Self-assembly of dodecyl groups on titania nanorods coated a titanium fibre for rapid and efficient solid-phase microextraction of polycyclic aromatic hydrocarbons from environment water

ABSTRACT A new organic-inorganic hybrid coated titanium fibre was developed via self-assembled modification for rapid and efficient solid-phase microextraction (SPME). Oriented titania nanorods (TiO2NRs) were in situ grown on the Ti wire as a fibre substrate through direct electrochemical anodisation. Subsequently, dodecyl groups were chemically bonded to the surface of TiO2NRs via self-assembly of n-dodecyltrimethoxysilane. The dodecyl-functionalised TiO2NRs coated Ti fibre was used to extract representative aromatic compounds coupled to high-performance liquid chromatography with UV detection. The new fibre exhibited excellent extraction efficiency and selectivity for the studied polycyclic aromatic hydrocarbons (PAHs) compared to commercial polydimethylsiloxane and polyacrylate fibres. The influential factors affecting the SPME process of PAHs were investigated and optimised. Under the optimised conditions, the developed method presented dynamic linear ranges from 0.03 to 500 μg·L−1 with correlation coefficients higher than 0.999 and limits of detection from 0.006 to 0.57 μg·L−1. Relative standard deviations (RSDs) varied between 3.51% and 4.93% and between 4.17% and 5.23% for intra-day and inter-day measurements with one single fibre, respectively. RSDs for the fibre-to-fibre reproducibility from 4.26% to 8.65% were achieved. The developed method was successfully applied to the selective preconcentration and determination of target PAHs in different environmental water samples. The relative recoveries from 89.62% to 113.1% were obtained with RSDs below 8.53%. Moreover, this fibre can be used over 200 times and fabricated in a precisely controllable manner.

Supramolecular imprinted polymeric stir bar sorptive extraction followed by high-performance liquid chromatography for endocrine disruptor compounds analysis

Molecular imprinted coatings based on β-cyclodextrin (β-CD) and acrylamide functional monomers were presented. The supramolecularly imprinted polymeric (SMIP) adsorption materials employed as the coatings of stir bar sorptive extraction (SBSE) for endocrine disruptor compounds (EDCs) analysis were proposed. A series of derivatized β-CDs functional monomers were synthesized and characterized. The best couple of functional monomers used for SMIP was selected from the β-CD monomers and common functional monomers, respectively. The ratio of two functional monomers was also optimized. The SMIP coatings showed good selectivity to the bisphenol A template and its structural analogs. It also provided enrichment factors ranging from 56 to 160 for bisphenols, which were 32- to 1600-fold higher than that of the commercial polyacrylate fibers (85 μm, Supelco). Moreover, the SMIP coatings displayed better selectivity and extraction amount than the nonimprinted and both single-functional monomer-based imprinted coatings, respectively. Therefore, the SMIP coatings triggered off a synergetic recognition for target analytes. The developed SMIP-SBSE-HPLC method was successfully applied for three environmental estrogen analysis in real water samples. A recovery of 92–119% and relative standard deviation of 1.6–9.7% were obtained. Taken together, the supramolecular imprinting strategy can provide new ideas for the development of novel supramolecular polymer-based adsorption materials, and can provide an efficient analytical method for the selective analysis of trace substances in environmental water samples.