Gel Technology Research Articles

Advanced Nanostructured Coatings Based on Doped TiO2 for Various Applications

For many years, TiO2-based materials and improving their properties in order to expand their application areas have been the focus of numerous research groups. Various innovative approaches have been proposed to improve the photocatalytic and gas-sensing properties of TiO2 nanostructures. In this review, we aim to synthesize the available information in the literature, paying special attention to the sol–gel technology, which is one of the most frequently used methods for TiO2 synthesis. The influence of dopants on the structural, morphological, optical, and electrical properties of TiO2 and the way to modify them in a controlled manner are briefly discussed. The role of shallow and/or deep energy levels within the TiO2 bandgap in the electron transport behavior of doped TiO2 is emphasized. Selected research on photocatalytic applications in water disinfection, wastewater treatment, and self-sterilizing coatings that contribute to improving the quality of human life and environmental preservation is highlighted. A survey of biosensors that are closely related to medical applications such as cancer detection, implantology, and osteogenesis is also provided. Finally, the pressing problems that need to be solved in view of the future development of TiO2-based nanostructures are listed.

Production of Exopolysaccharide-Based Porous Structures for Biomedical Applications: A Review.

Exopolysaccharides, obtained from microorganisms as fermentation products, are interesting candidates for biomedical applications as scaffolds: they are biocompatible, nontoxic, antimicrobial, antitumor materials. To produce exopolysaccharide-based scaffolds, sol-gel technology could be used, which ends with the removal of the liquid phase from the polymeric network (i.e., the drying step). The aim of this review is to point out the most relevant strengths and weaknesses of the different drying techniques, focusing attention on the production of exopolysaccharide-based porous structures. Among these drying processes, supercritical carbon dioxide-assisted drying is the most promising strategy to obtain dried gels to use in the biomedical field: it produces highly porous and lightweight devices with outstanding surface areas and regular microstructure and nanostructure (i.e., aerogels). As a result of the analysis carried out in the present work, it emerged that supercritical technologies should be further explored and applied to the production of exopolysaccharide-based nanostructured scaffolds. Moving research towards this direction, exopolysaccharide utilization could be intensified and extended to the production of high added-value devices.

Creation of Next-Generation Plant-Based Seafood Using Emulsion Gel Technology: Omega-3-Enriched Sea Foie Gras Analogs

Plant-based seafood analogs are gaining increasing popularity as replacements for traditional fish and other seafood products due to environmental (stock depletion, pollution, and bycatch issues) and health (bioaccumulated toxins, norovirus, and allergies) concerns associated with them. Several companies have launched plant-based fish products, but the market still lacks alternatives to shellfish and other sea delicacies. In this study, a plant-based sea foie gras (monkfish liver product) analog was developed using duckweed RuBisCO protein and omega-3-rich flaxseed oil to form emulsion gels. These gels consisted of a high concentration of flaxseed oil droplets dispersed within a gelled RuBisCO protein network. It was hypothesized that the high disperse phase volume fraction of the oil droplets and the heat-set gelation properties of the RuBisCO proteins would enable us to create emulsion gels that mimicked the properties of sea foie gras. A natural pigment (β-carotene) was incorporated into the oil phase of the emulsions to mimic the red-orange color of conventional sea foie gras. The structural, textural, and optical properties of real and plant-based sea foie gras analogs were characterized using scanning electron microscopy, confocal microscopy, dynamic shear rheology, texture profile analysis, and colorimetry. Emulsion gels prepared using 40% flaxseed oil and 10% RuBisCO proteins produced plant-based products that closely simulated the texture and color of the real products. Rheological analysis suggested that the oil droplets acted as active fillers within the protein gels. Our results suggest that emulsion gels may be used to create more sustainable and healthier plant-based seafood products.

Evaluation of Critical Parameters for the Fabrication of Metal Hollow Spheres Using an Alginate‐Based Sol–Gel Process

This study focuses on the fabrication of metal hollow spheres using an alginate‐based sol–gel technology in combination with a freeze‐drying process. The mixing routine for the metal slurry is investigated. Critical processing parameters, influencing the yield of intact spheres such as the aging time in the reaction solution and in water as well as the freezing time and the rotation of the spheres during freezing are evaluated with statistical design of experiments. A customized debinding regime is developed with a heating rate of 0.1 K min−1 in critical temperature ranges and a maximum temperature of 350 °C. For the fabrication of hollow metal spheres with additions of 1.0 wt% potassium alginate, the optimum aging time in Ca(OH)2‐reaction solution is 4 min (4C) and the spheres are only to be rinsed with purified water (0 W). Furthermore, the rotation of the spheres (+R) during freezing significantly contributes to the increased yield of 80.2%, which is significantly higher as compared to the previous studies. Sintered spheres have a compressive strength of 159 MPa with a corresponding strain of 42%.

Development of an Energy Harvesting System for the Conversion of Mechanical Energy of Human Movement into Electrical Energy and Its Integration into High Performance Wearable Clothing

In many smart textile development studies, sensors and electro-conductive yarns have been widely investigated and used as essential components, especially in the fields of medicine, sport, work wear, and special applications. Wearable sensors provide a means to monitor the wearer’s health through physiological measurements in a natural setting or are used to detect potential hazards and alert users and/or caretakers. The aim of the research is to develop a prototype of wearable electronics that consists of high-performance clothing with an integrated energy harvesting system for converting the mechanical energy of human movements into electrical energy. Within the framework of the research, a system for determining human physiological and/or environmental parameters and transmitting data was developed and integrated into clothing modified with sol–gel technology for indoor and outdoor use. Although the created flat inductive elements of the energy harvesting system retain their performance during the hydrothermal treatment process, at the same time, the other elements of the smart clothing system (especially electro-conductive yarns) rapidly lose their electrical conductivity. The modified knitwear provided a longer time between washing cycles to protect the embedded wearable electronics, and the impact of surface modification with sol–gel on wearing comfort was evaluated.

Design and fabrication of a new sol-gel based sensor for the visual detection of oxalate and investigation of the effect of boiling on the oxalate content of some foods

Sol–gel chemistry is a unique method for constructing high-performance flexible sensors. Sol-gel silica matrices doped with a controlled amount of sensing agent (dopant) lead to the fabrication of suitable sensors. According to this knowledge, we decided to describe the development and performance characteristics of the sol-gel glasses with a nanoporous structure as the novel naked eye sensor for fast detection of oxalate based on the incorporation of indole inside pores of the silica matrix obtained by sol–gel technology. Several sols were made with different water: alkoxide ratios and pHs to design a highly sensitive and selective thin film without dopant leaching. The Field emission scanning electron microscopy (FE-SEM) technique was employed to evaluate the surface morphology and porosity growth. Also, the sol–gel films were characterized by Fourier-transform infrared (FTIR) spectroscopy. The optimum performance in terms of sensitivity, leaching, and response time was achieved using water: alkoxide ratio of 4:1, water acidity (HCl concentration) of 0.01 M, and ethanolic solution of Indole 0.01 mol L-1. The calibration plot was obtained within 0.01–6.00 μg mL−1 of oxalate with a detection limit value of 0.005 μg mL−1. Meanwhile, the prepared sensor exhibited excellent and acceptable RSDs for both inter-day and intra-day precision. The present sensor was used to measure oxalate in various samples and investigate the effects of the celeryʼs cooking time and the brewing duration of tea on oxalate content.

P‐IG‐31 | Modernization of Phenotyping Using Gel Technology with Ongoing Validation Process

P‐IG‐31 | Modernization of Phenotyping Using Gel Technology with Ongoing Validation Process

Fiber Type Identification of Human Skeletal Muscle.

The technique described here can be used to identify specific myosin heavy chain (MHC) isoforms in segments of individual muscle fibers using dot blotting, hereafter referred to as Myosin heavy chain detection by Dot Blotting for IDentification of muscle fiber type (MyDoBID). This protocol describes the process of freeze-drying human skeletal muscle and isolating segments of single muscle fibers. Using MyDoBID, type I and II fibers are classified with MHCI- and IIa-specific antibodies, respectively. Classified fibers are then combined into fiber type-specific samples for each biopsy. The total protein in each sample is determined by Sodium Dodecyl-Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) and UV-activated gel technology. The fiber type of samples is validated using western blotting. The importance of performing protein loading normalization to enhance target protein detection across multiple western blots is also described. The benefits of consolidating classified fibers into fiber type-specific samples compared to single-fiber western blots, include sample versatility, increased sample throughput, shorter time investment, and cost-saving measures, all while retaining valuable fiber type-specific information that is frequently overlooked using homogenized muscle samples. The purpose of the protocol is to achieve accurate and efficient identification of type I and type II fibers isolated from freeze-dried human skeletal muscle samples. These individual fibers are subsequently combined to create type I and type II fiber type-specific samples. Furthermore, the protocol is extended to include the identification of type IIx fibers, using Actin as a marker for fibers that were negative for MHCI and MHCIIa, which are confirmed as IIx fibers by western blotting. Each fiber type-specific sample is then used to quantify the expression of various target proteins using western blotting techniques.

Surface electromyography using dry polymeric electrodes.

Conventional wet Ag/AgCl electrodes are widely used in electrocardiography, electromyography (EMG), and electroencephalography (EEG) and are considered the gold standard for biopotential measurements. However, these electrodes require substantial skin preparation, are single use, and cannot be used for continuous monitoring (>24 h). For these reasons, dry electrodes are preferable during surface electromyography (sEMG) due to their convenience, durability, and longevity. Dry conductive elastomers (CEs) combine conductivity, flexibility, and stretchability. In this study, CEs combining poly(3,4-ehtylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) in polyurethane are explored as dry, skin contacting EMG electrodes. This study compares these CE electrodes to commercial wet Ag/AgCl electrodes in five subjects, classifying four movements: open hand, fist, wrist extension, and wrist flexion. Classification accuracy is tested using a backpropagation artificial neural network. The control Ag/AgCl electrodes have a 98.7% classification accuracy, while the dry conductive elastomer electrodes have a classification accuracy of 99.5%. As a conclusion, PEDOT based dry CEs were shown to successfully function as on-skin electrodes for EMG recording, matching the performance of Ag/AgCl electrodes, while addressing the need for minimal skin prep, no gel, and wearable technology.

Insights into the Reactivity of Gd2−xSrxFe2O7 (x = 0 ÷ 0.4) in CO Radical Hydrogenation

The effect of strontium substitution in the structure of the complex oxide Gd2SrFe2O7 on the production of light olefins by CO hydrogenation was investigated. Perovskite-type oxides Gd2−xSr1+xFe2O7 (x = 0; 0.1; 0.2; 0.3; 0.4) were synthesized by sol–gel technology and characterized by XRD, Mössbauer spectroscopy, BET specific area, acidity testing, and SEM. The experimental data revealed a correlation between the state of iron atoms, acidity, and catalytic performance. It was found that with an increase in the content of Sr2+ in the perovskite phase, the basicity of the surface and the oxygen diffusion rate increased. This contributed to the CO dissociative adsorption, formation of active carbon, and its further interaction with atomic hydrogen.

Application of Hydrogels and Hydrocarbon-Based Gels in Oil Production Processes and Well Drilling.

The use of gels in oil production processes has become a regular practice in oilfield operations and is constantly developing in all oil-producing countries of the world, as evidenced by the growth of publications and patent activity on this topic. Many oil production processes, such as hydraulic fracturing, conformance control, water, and gas shutoff, cannot be imagined without the use of gel technologies. Inorganic, organic, and hybrid gels are used, as well as foams, gel-forming, and gel-dispersed systems. The possibility of a broad control of structural and mechanical properties, thermal stability, and shear resistance by introducing microscale and nanoscale additives made hydrogels and hydrocarbon-based gels indispensable tools for oil engineers.

Synthesis and assessment of properties of ZrB2 nanopowder utilizing boro/carbothermal reduction method

AbstractThe reason of this study is to synthesize ZrB2 nano powder utilizing boric acid and phenolic resin. Within the study of zirconia as a source of zirconium, boric acid was used as a source of boron and phenolic resin as a carbon source. The theoretical and experimental studies of ZrB2 were synthesized by boro/carbothermal diminishment from the novel sol–gel technology. The zirconia powder was crushed for 8 h and in conjunction with different molar proportions of boric acid, in this consider, a kinetic demonstrate for reactions creating ZrB2 was built up based on thermodynamic analysis. The resultant powder was synthesized in a neutral atmosphere controlled in 1450°C and 1550°C. After it was also observed that, with the increase of molar proportion of H3BO3, the reaction delivered ZrB2 powders in high amount of the boron reaction. The compound was analyzed by an X‐ray diffraction technique and found to be ZrB2 powder that was synthesized with the purity of approximately 98%.

Developing concentrated emulsion gel hybrids structured by natural food fibres

The integration of healthy unsaturated fat into plant-based meat alternatives is being advocated worldwide but remains technically challenging, due to limitations in the textural qualities and processability of edible oil. One way to improve the rheological behaviour of oil is via emulsion gel technology. However, adaptable solutions for real-life food processing are few and far between. On this basis, we formulated physically stable emulsion gel hybrid templates with 50–83% sunflower oil load, mostly oil-in-water microstructure, and structured solely by natural food fibres without using oleogelators. The fibres included citrus fibre and soy polysaccharides as emulsifying fibres, and curdlan and deacetylated konjac glucomannan as structuring fibres. Upon heating, they developed stiffness up to 10E4 Pa in storage modulus G′. Here, we present the first characterisation of such fibre-based emulsion gel hybrids through analysis by epifluorescence microscopy, oscillatory rheology, and diffusing wave spectroscopy, and report underlying composition-structure-rheology-thermal behaviour relations. The key findings are that strength in the emulsion gel hybrid could come from combinations of the following observed mechanisms: (i) tiny droplets of dispersed phase droplets with high curvature, (ii) emulsifying fibre of high molecular weight, (iii) controlled interference from emulsifying fibre on the viscoelastic network development of structuring fibre, and (iv) for additional shear stability, highly aggregated state of dispersed phase droplets without coalescence. Promising templates bearing close resemblance to animal fat references such as pork belly fat (in terms of G′), and shear stability with potential toward extrusion and food printing application have been identified.

Battery selection criteria for electric vehicles: techno-economic analysis

In this study, different battery types to be used in the conversion of a small and light (600-1000 kg) internal combustion engine vehicle into an electric vehicle were analyzed. The study was conducted to ensure that this vehicle is suitable for urban use and has a range of approximately 100 km. Each battery technology capacity is evaluated to be approximately 15 kWh. While performing the techno-economic analysis of different battery types, it was taken into account that they provide the necessary energy for about 10 years. Seven different battery technologies (lead-acid, gel, Ni-Cd, Li-Ion, LiFePo4, LiPo, Ni-MH) were used for comparison. In the analysis; price assessment in US Dollars ($), 10-year investment cost, weight and volume values, weight and volume values required to produce 1 kWh of energy were presented in tables. In addition to these, a review of battery life was made. Finally, the advantages and disadvantages of battery technologies compared to each other are given. As a result of the study, it was seen that the cheapest technology for a 10-year lifespan was lead-acid technology. It has been determined that lead-acid technology is 30% cheaper than the second cheapest gel technology and 82% cheaper than the most expensive technology, LiPo technology. In the study, it was revealed that the lightest technology was LiPo. It has been determined that this technology is 85% lighter than gel technology. Besides this information, data on cycle life, self-discharge, advantages and disadvantages are presented in tabular form.

NEW APPROACH TO SIMULATION AND EFFICIENCY PREDICTION OF PRECIPITATION AND GEL ENHANCED OIL RECOVERY METHODS

Link for citation: Fedorov K.M., Gilmanov A.Ya., Shevelev A.P. New approach to simulation and efficiency prediction of precipitation and gel enhanced oil recovery methods. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 5, рр.85-93. In Rus. Relevance. The problem of conformance improvement by precipitation and gel technologies application may be associated with mathematical objective with infinitesimal parameter in which size of gel plug placement in the near wellbore zone of injector is significantly less than interwell distance. Existing approaches to modeling this problem do not allow describing all the effects associated with low-volume injections. The objective of the article is to suggest the approach to simulation and efficiency prediction of precipitation and gel injection technologies. Objects: oil reservoirs on which precipitation and gel enhanced oil recovery methods are used. Materials and methods. New approach to modeling such a problem consists of gluing the optimization objective of injection profile conformance and objective of the prediction of surrounding producers’ response. This approach is briefly described in the paper and is validated by the comparison of calculated data with the results of statistical processing of the data of precipitation and gel enhanced oil recovery technologies application on the fields of one of Russian oil companies. Results. Processing of the accumulated field experience in the use of these technologies has shown that the specific values of additional oil production after the operation of conformance improvement grow with the increase in the introduced criterion of processing efficiency – the conformance improvement coefficient and, conversely, decrease with a drop in the well injectivity coefficient after processing. The proposed approach to forecasting and evaluating the effectiveness of the use of technologies to conformance control is the basis of a line of mathematical models for the use of gel, precipitation and suspensions injection technologies.

Using the method of molecular genetic typing to determine variants of the weak antigen D in the diagnosis of Rh-affiliation

Background. Determination of Rh-affiliation is mandatory for donors and recipients, surgical patients, pregnant women, etc. There are variants of the D antigen that are difficult to identify by serological methods, for example, a weak D antigen.
 Aim. Determination of Rh-affiliation using genotyping in difficult cases, when the use of serological methods does not allow obtaining a reliable result.
 Material and methods. We studied blood samples from donors (n=18), pregnant women (n=17) and patients with hematological diseases (n=15): 22 men and 28 women, median age 36 years (25 to 54 years). Serologically, antigen D was determined by gel technology in ID-cards and in an indirect antiglobulin test with anti-D-IgG reagent. Weak D antigen variants were diagnosed and phenotype determined using polymerase chain reaction with allele-specific primers. For significance of differences in the frequency of types of weak antigen D, a nonparametric statistical method using a two-tailed Fisher's exact test was used. Differences were considered statistically significant at p 0.05.
 Results. The use of genotyping made it possible to detect the presence of a weak antigen D in 41 samples. Its specificity was represented by the following types: 1; 1.1; 2; 3. Other types of weak antigen D [4; 4.0; 4.1; 4.2 (DAR); 5; 11; 14; 15; 17] were absent. The study of the phenotype of erythrocyte antigens of the Rhesus system using genotyping revealed the predominance of the Ccee phenotype in people with a weak D antigen. Significant differences in the frequency of types of this antigen were revealed.
 Conclusion. The use of molecular genetic typing made it possible to determine the types of the weak antigen D and to accurately determine the Rh-affiliation of the subjects.

Boosting resistance to H2O and SO2 in low-temperature NH3-SCR denitrification reaction by W addition in Cu0.1-mWmTiOx (m = 0.05–0.09) due to modulating the synergistic effect of oxidation property and acidity

It remains a challenge to obtain competitive low-temperature NH3-SCR denitrification catalyst with excellent resistance to H2O and SO2. Herein, Cu0.1-mWmTiOx (m = 0.05, 0.06, 0.07, 0.08, 0.09) catalysts for application in NH3-SCR denitrification were synthesized by the sol–gel technology. These catalysts were characterized by XRD, separate NO/NH3 oxidation, NH3-TPD, NO-TPD, SO2-TPD, N2 physical adsorption, H2-TPR, TEM, XPS and in-situ DRIFTS to analyze the impact of W introduction on NH3-SCR of NO reaction. The results demonstrate that the Cu0.1-mWmTiOx catalysts have higher catalytic activity and N2 selectivity than Cu0.1TiOx without adding W, in which the Cu0.03W0.07TiOx catalyst exhibits significantly improved the H2O/SO2 resistance and a wide window of activity at 210–420 °C, having a 100% NO conversion and >90 % N2 selectivity. By comparison with the Cu0.1TiOx catalyst, the oxidation capability of the Cu0.1-mWmTiOx catalysts decreases with the addition of W, but the acidity is enhanced. The better NH3-SCR activity of Cu0.03W0.07TiOx may be linked with the synergistic effect of the moderate oxidation property and the enhanced surface acidity of the catalyst. Especially, in-situ DRIFTS under various conditions was used to analyze to the good H2O/SO2 tolerance at low temperature after the W addition in the Cu0.03W0.07TiOx catalyst, which shows the W addition effectively suppresses the SO2 oxidation to form sulfate with copper of the catalyst, prevent the competitive adsorption of H2O and NOx, and does not affect NH3 adsorption. In addition, the possible SCR reaction process was proposed on Cu0.03W0.07TiOx catalyst based on various characterizations.

Synthesis of ceria nanoparticles for the catalytic activity of cyclohexene epoxidation and selective detection of nitrite

Based on a few noteworthy features, cerium oxide nanoparticles have gained significance in nanotechnology. The effective microwave combustion method (MCM) and the conventional sol–gel (CRSGM) technologies are used in this study to successfully generate the crystalline CeO2 nanoparticles (NPs). Additionally, using a variety of spectroscopic and analytical methods, the synthesized CeO2 NPs are examined to assess to understand their structure and morphology. The XRD patterns of CeO2 NPs show that the structure exhibits a face-centered cubic lattice. Then, with demonstrated good conversion and selectivity, the impact of the epoxidation reaction of cyclohexene was examined. Finally, it can be said that using CeO2 nanoparticles is an efficient strategy to increase the catalytic activity toward the epoxidation reaction of cyclohexene. In the presence of acetonitrile as a solvent and H2O2 as an oxidant, the catalyst samples utilized in the cyclohexene epoxidation reaction were examined. In this study, the CeO2 catalyst outperformed all other catalysts in terms of cyclohexene maximal conversion and selectivity. After six prolonged cycles, the conversion of cyclohexene oxidation using CeO2 NPs shows reasonable recyclability and conversion efficiency, making it the best catalyst for an industrial production application.Additionally, the upgraded CeO2 nanoparticle electrode for nitrite detection has a linear concentration range (0.02–1200 M), a low detection limit (0.22 M), and a higher sensitivity (1.735 A M−1 cm−2). CeO2 NPs, on the other hand, have a quick response time, excellent sensitivity, and high selectivity. Additionally, the manufactured electrode is used to find nitrite in various water samples. Finally, it can be said that using CeO2 NPs is an efficient strategy to increase the catalytic activity toward cyclohexene oxidation and nitrite.

Characterisation of self cleaning banana fabrics using titanium dioxide nano sol for stain degradation

ABSTRACT The self-cleaning concept has drawn a lot of attention due to its unique characteristics and wide range of potential applications in a variety of sectors. In the present study, the photocatalytic properties of TiO2 nanoparticles for achieving the self-cleaning ability on banana fabric were explored using sol–gel technology. Highly stable TiO2 nano sols were developed using a simple, rapid, and relatively low acid content process at low temperatures. Pad-dry-cure method was used to obtain a homogeneous coating of TiO2 nano sols on the surface of the banana fabric. The coated fabrics were characterised using techniques like Scanning Electron Microscopy, Energy Dispersive X-Ray Spectroscopy, Fourier Transform Infrared Spectroscopy, X-Ray Diffraction, and UV–Vis Spectroscopy. After light irradiation, the photocatalytic activity was determined by stain degradation of different stains by analysing colour difference and K/S. Anatase TiO2 nanoparticles were formed in good concentration exhibiting photocatalytic activities shown by the photodegradation of Coffee and Rhodamine B stains on exposure to light. Overall, the proposed method can incorporate titanium dioxide functionalization of a new class of cellulosic-based materials, i.e. banana fabrics intended for self-cleaning applications, in a stable, rapid, cost-effective, and ecologically acceptable manner.

Magnet Integrated Fabric Phase Sorptive Extraction for the Extraction of Resin Monomers from Human Urine Prior to HPLC Analysis

In this work, a method for the simultaneous determination of four resin monomers: Bisphenol A, bisphenol A methacrylate glycidate, triethyleneglycol-dimethacrylate, and urethane dimethacrylate, from human urine using magnet integrated fabric phase sorptive extraction (MI-FPSE), followed by high performance liquid chromatography (HPLC) diode array detection (HPLC-DAD), is presented. MI-FPSE is a novel configuration of FPSE that incorporates the stirring and extraction mechanism into one device, resulting in an improved extraction kinetic factor. FPSE is a green sample preparation technique that uses a flexible surface, such as cellulose, coated with a polymeric material using sol–gel technology. Poly(tetrahydrofuran) (PTHF) material was selected, due to its higher efficiency in terms of recovery rate among the studied MI-FPSE membranes. Optimization of the extraction process was performed based on several extraction and elution parameters. The method was validated for its linearity, selectivity, accuracy, precision, and stability of the samples. For the four compounds, the LOD and LOQ were 0.170 ng/μL and 0.050 ng/μL, respectively. The relative standard deviation of the method was less than 9.8% and 11.9%, for the within-day and between-day precision, respectively. The relative recoveries were between 85.6 and 105.2% in all cases, showing a good accuracy. The effectiveness of the proposed method was confirmed through successful application to the bioanalysis of real urine samples.