Rapid Method For Determination Research Articles

A Rapid Analysis Method for Determination of Hydrocarbon Types in Aviation Turbine Fuel by Gas Chromatography-Mass Spectrometry.

A rapid analysis method for determination of hydrocarbon types in aviation turbine fuel was investigated in this study. A kind of reversible adsorption material packed as an unsaturated trap was used to separate saturated hydrocarbons and unsaturated hydrocarbons in the GC-MS system. No manual process or organic reagent was needed during the entire analysis process. The contents of 13 kinds of hydrocarbons, including paraffins, monocycloparaffins, dicycloparaffins, tricycloparaffins, monoolefins, cycloolefins, alkylbenzenes, CnH2n-8 aromatics, CnH2n-10 aromatics, naphthalenes, CnH2n-14 aromatics, CnH2n-16 aromatics, and CnH2n-18 aromatics were calculated by the characteristic mass fragments detected by MS with the modified matrices of ASTM D2425. The overall analysis time was less than 10 min. The precision of this test method has been conducted with 8 laboratories attended and 16 samples analyzed. The performance of this new method was demonstrated by comparing the results tested by ASTM D1319, ASTM D2425, and ASTM D6379. This rapid analysis method can provide hydrocarbon compositions of aviation turbine fuels or other liquid hydrocarbon samples within the same distillation range.

Analysis of the slump test for on-site yield stress measurement of thickened tailings

Yield stress of thickened tailings is a basic parameter in the design of tailings pipeline transport and discharge systems. To accurately determine the yield stress of thickened tailings, it is essential to develop a rapid determination method suitable for engineering applications and explore the relationship among various factors. In this paper, a high-precision velocity-controlled slump test system was designed to investigate the effects of thickened tailings temperature, lifting speed, slump cylinder shape, and tailings slurry mass concentration on the slump value. The test results indicate that the slump value decreases with the increases in thickened tailings temperature, resulting in a higher yield stress. Lifting speed significantly affects the yield stress, a faster lifting speed produces a larger slump value, which in turn leads to a smaller calculated yield stress. The lifting speed of 0.01 m/s provides a yield stress calculation that is close to the actual value. Moreover, among the tested slump cylinder shapes, the results obtained from the cylinder with dimensions of 100 mm (height) × 100 mm (diameter) are the closest to the actual values. These findings offer technical support for rapid and accurate on-site testing of the rheological parameters of thickened tailings and provide theoretical support for developing disposal methods for tailings.

Fast Determination and Source Apportionment of Eight Polycyclic Aromatic Hydrocarbons in PM10 Using the Chemometric-Assisted HPLC-DAD Method

Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds that are both toxic and hazardous to human health and ecological systems. In recent work, a novel analytical strategy based on the chemometric-assisted HPLC-DAD method was proposed for the quantification and source apportionment of eight PAHs in PM10 samples. Compared to traditional chromatographic methods, this approach does not require the purification of complex PM10 samples. Instead, it utilizes a mathematical separation method to extract analytes’ profiles from overlapping chromatographic peaks, enabling precise quantification of PAHs in PM10. Firstly, 40 PM10 samples collected in Loudi city during two sampling periods were used for analysis. Subsequently, the second-order calibration method based on alternating trilinear decomposition (ATLD) was employed to handle the three-way HPLC-DAD data. Finally, the pollution sources of PAHs were analyzed by the feature component analysis method according to the obtained relative concentration matrix. For the validation model, the average recoveries of eight PAHs were between (88.8 ± 7.6)% and (105.6 ± 7.5)%, and the root-mean-square errors of prediction ranged from 0.03 μg mL−1 to 0.47 μg mL−1. The obtained limits of quantification for eight PAHs were in the range of 0.0050 μg mL−1 to 0.079 μg mL−1. For actual PM10 samples, results of the feature component analysis indicated that the main source of PAHs in PM10 may be traffic emissions and coal combustion. In summary, the proposed method provided a new and rapid analysis method for the accurate determination and source apportionment of PAHs in atmospheric aerosols.

Research progress on femoral attachment positioning during medial patellofemoral ligament reconstruction

To review research progress on femoral attachment positioning during medial patellofemoral ligament (MPFL) reconstruction, so as to provide a reference for accurate positioning in clinic. The literature at home and abroad on femoral attachment positioning during MPFL reconstruction was extensively reviewed and summarized. MPFL is the main ligament that restricts patellar outward migration, so MPFL reconstruction is the main treatment for patellar dislocation, but the accuracy of intraoperative femoral attachment positioning will significantly affect the effectiveness. At present, there are three main methods for femoral attachment positioning in MPFL reconstruction, including imaging positioning, bony landmark positioning, and new technology. Among them, the main imaging positioning method is the "Schöttle point" method, but it has high requirements for fluoroscopic positioning, and can only be accurately positioned under standard lateral fluoroscopy of the femur. The bony landmark positioning method mainly locates the femoral attachment by touching or dissecting the bony landmarks such as adductor tubercles and medial epicondyle of femur, but its disadvantages are that the positioning is not accurate enough, the intraoperative visual field exposure requirements are high, and a large incision is required. In order to avoid the problem that the simple bony landmark positioning method, in recent years, the combination of bony landmarks combined with arthroscopy, three-dimensional (3D) printing technology, and robot-assisted positioning methods have begun to be used in clinical practice. New technology localization methods have shown good results by preparing guides before operation, planning positioning paths in advance, or directly using robots to assist positioning during operation. The accurate positioning of the femoral attachment in MPFL reconstruction is crucial, and the method of accurate and rapid intraoperative determination needs to be further improved and optimized. In the future, it is expected that the combination of computer image recognition correction technology and intraoperative position assistance will solve this problem.

A New Validated Method for Rapid Determination of OLEU Concentration in Dietary Supplements: Comparison with Total Phenol Content and Antioxidant Activity

The market for olive leaf dietary supplements is expanding rapidly and is valued at $437.15 million today. However, information on the control of these products is sketchy and the origin and variety of olives are rarely stated. The aim of this research was to validate a simple and rapid screening method for oleuropein determination in olive leaf dietary supplements. A matrix blank was prepared by removal of oleuropein from a mixture of dietary supplements and the matrix was then spiked with known concentrations to create a spiked matrix calibration curve in the range 5 - 40% oleuropein. Five replicate extractions and analyses of the matrix standards were carried out over 10 days. Precision was less than 6% RSD and linearity was demonstrated by the Fischer test. Extraction recovery was > 90% and there was a strong linear relationship between authentic and matrix standards. All tested products conformed to the label claim which was strongly correlated with total polyphenols measured by the Folin-Ciocalteau method. Antioxidant activity was measured by the DPPH assay and was found to be strongly correlated with total phenol content and oleuropein concentration.

Electrochemical Determination of Tartrazine and Carmoisine Dyes from Aqueous Solutions on Modified Electrodes

Introduction: The recognition of the health hazards of azo dyes has highlighted the need to develop efficient, rapid, and reliable analytical methods for dye determination. Method: In this work, electrochemical probing of the azo group of Tartrazine (TZ) and Carmoisine (CR) in food dyes was carried out. Synthesized bismuth and zinc oxide nanoparticles were used to modify Graphite Electrode (GE). Results: Electrochemical analysis showed a much better electrochemical response using ZnO+Bi/GE as a modifier than individually nanoparticle-modified graphite electrodes. From the CV analysis, it was found that both the dyes exhibited irreversible electrochemical behavior, and the redox parameters were calculated. The Limit of Detection (LOD) values recorded for TZ and CR for ZnO+Bi/GEbased sensors were 0.84 uM and 2.80 uM, respectively. The obtained sensitivity values were 11.86 uA/uM/cm2 for TZ and 17.3 uA/uM/cm2 for CR. Conclusion: The sensor evidently demonstrated reliable simultaneous detection of both dyes, making it suitable for practical applications in food safety analysis.

Simplified approach to retention times of narrow binary pulses in the case of ideal chromatography model and Langmuir isotherm

Analytical solution to ideal chromatography model has been established for binary Langmuir isotherm and rectangular injections. However, retention time of the less adsorbed species, which is of great theoretical and practical significance, cannot be given in a closed form and is conventionally solved by numerical integration with a floating boundary. A simplified approach is provided in this article. A 4th order algebraic equation was derived and used to solve the maximum concentration that can be further used to explicitly calculate retention time. Under most practical conditions, reliable initial guess can be easily acquired, allowing for the application of Newton-Raphson method for rapid determination of the root of the 4th order equation. In addition, derivatives of retention time with respective to isotherm parameters can be given in analytical forms.

Characterization of 37 enological tannins using a multiple technique approach: Linear sweep voltammetry as a rapid method both for classification and determination of antioxidant properties

In this work, 37 enological tannins of different classes were studied to investigate whether linear sweep voltammetry (LSV) could be a method to determine the family of a sample and its antioxidant capacity. A “wholistic” approach was used, combining LSV data with nuclear magnetic resonance (NMR), polyphenol quantification (Folin-Ciocalteu method and gravimetric analysis), antiradical activity (DPPH assay), and reducing capacity (FRAP assay). Voltammetric data were processed with statistical techniques and the results show the clustering of tannins in three different classes: ellagitannins, gallotannins, and condensed tannins. These findings were confirmed by NMR data treated with the same procedure. Finally, ellagitannins showed a high reducing capacity and gallotannins showed a high antiradical capacity. Importantly, LSV indices were shown to be significantly correlated with DPPH and FRAP parameters. Therefore, the hypothesis of LSV as a potentially useful technique to choose the most suitable tannin for a determined antioxidant purpose was successfully proved.

Exopolysaccharides as bio-based rheology modifiers from microalgae produced on dairy industry waste: Towards a circular bioeconomy approach

The feasibility of exopolysaccharides (EPS) production from cheese whey using Chlorella vulgaris was investigated as an example of circular bioeconomy application. The effects of dairy waste utilization in EPS biosynthesis and rheological properties were evaluated, comparing with both control conditions and commercial xanthan gum (CXG). A twofold increase in yield, up to 0.32 g L−1, was observed when Chlorella vulgaris was used for EPS production from whey rather than conventional fertilizers. Additionally, the EPS produced using cheese whey exhibited superior pseudoplasticity in the 0.4–1.0 (w/v) range compared to the control. The EPS from the whey wastewater contained functional groups similar to those of CXG (82.7 %). Moreover, the solutions containing 1 % biopolymer showed rheological profiles similar to those of the 0.4 % CXG. The molecular weight averages predominantly fell within the range of 284 to 324 kDa, as deduced using diffusion NMR, an innovative and rapid determination method for estimating EPS size. The potential applications of EPS notably extend beyond the dairy industry, reaching diverse market sectors, and thereby enhancing the competitiveness of microalgal biorefineries while contributing to the achievement of Sustainable Development Goals.

Rapid determination of oil content of single peanut seed by near-infrared hyperspectral imaging

Oil content is a crucial indicator for evaluating the quality of peanuts. A rapid and non-destructive method to determine oil content of individual peanut seed can provide robust technical support for breeding high-oil-content peanut varieties. In this study, we established a rapid determination method using near-infrared hyperspectral imaging and chemometrics to assess the oil content of single peanut seed. After selecting key wavelengths through competitive adaptive reweighted sampling (CARS), uninformative variable elimination (UVE), and random frog (RF), we constructed an oil content calibration model based on partial least squares regression for single peanut seed. Validation results demonstrated that the correlation coefficient was 0.8393 with a root mean square error of 1.7771 in the calibration set, while it was 0.7915 with a root mean square error of 2.2943 in the independent prediction set. Most samples exhibited relative errors below 5%, confirming the reliability of this model in predicting oil content of single peanut seed.

Real-world performance of susceptibility testing for cefiderocol: insights from a prospective multicentre study on Gram-negative bacteria.

Cefiderocol is a novel siderophore-conjugated cephalosporin developed for the treatment of multidrug-resistant Gram-negative bacterial (GNB) infections. However, the current gold standard for cefiderocol susceptibility testing, broth microdilution (BMD) using iron-depleted cation-adjusted Mueller-Hinton broth, presents challenges for many microbiology laboratories. In this study, we evaluate the real-world performance of disc diffusion (DD) and a commercial BMD method (ComASP®) to test cefiderocol susceptibility in a series of isolates collected prospectively from severely ill patients in a multicentre study. The susceptibilities of 1472 isolates (632 Enterobacterales, 532 Pseudomonas aeruginosa, 84 Acinetobacter spp. and 224 Stenotrophomonas maltophilia) collected in 60 Spanish hospitals were analysed following the EUCAST 2023 and 2024 criteria. We assessed the performance of DD (cefiderocol 30 μg disc, Liofilchem) and a commercial BMD method (ComASP® Cefiderocol, Liofilchem). A total of 1408 and 1450 isolates were susceptible by DD and ComASP® BMD, respectively. Overall, the agreement between both methods was 96.9%. Forty-four isolates were resistant by DD but susceptible by ComASP® BMD, and two were susceptible by DD but resistant by ComASP® BMD (Acinetobacter baumannii isolates). Adoption of the updated 2024 EUCAST DD breakpoints and areas of technical uncertainty (ATUs) led to a decrease in susceptibility among Enterobacterales (95.3% versus 92.6%). DD is a straightforward, rapid and accessible method for routine determination of cefiderocol susceptibility in real-world practice. ComASP® BMD shows a high agreement with DD in susceptible isolates and may help to resolve DD interpretability concerns in isolates with susceptibility results within the ATU, but caution is warranted when testing resistant isolates.

Development of new methods for Determination of Sulpha Drugs with N-Chlorosacchrin Reagent

Sulpha drugs (sulphanilamide and their derivatives) are widely used as antibacterial drugs. An accurate and rapid method for quantitative determination of sulpha drugs and sulphanilamide would be of great importance. In literature several methods have been discussed for determination of sulphanilamide. The previous methods upon the evaluation of their nitrogen and sulphur contents while the latter were based upon the reaction of functional groups present in them.

A Rapid, Sensitive, and High-throughput Method for the Simultaneous Determination of Antihypertensive Drug Combinations in Dog Plasma by UHPLC-MS/MS: The Assessment of Predicable Bioequivalence of In-vitro Dissolution Condition.

Essential hypertension is a common clinical disease and a risk factor for cardiovascular and cerebrovascular diseases. Olmesartan medoxomil, amlodipine, and hydrochlorothiazide are commonly used antihypertensive drugs. The aim of this study was to establish a robust UPLC-MS/MS method for the simultaneous determination of olmesartan medoxomil, amlodipine, and hydrochlorothiazide in dog plasma. At the same time, the in vivo and in vitro release studies were conducted, and a preliminary in vitro-in vivo correlation (IVIVC) evaluation was performed. The bioequivalence experiment was conducted with a double-crossed design. Three major components were extracted and analyzed by UHPLC-MS/MS. With the MRM scan, olmesartan and amlodipine were quantified by fragment conversion (m/z 447.10→190.10) and (m/z 408.95→294.00) under positive ESI mode, while hydrochlorothiazide was quantified with fragment conversion (m/z 295.90→268.90) under negative ESI mode. The in vitro release studies were performed using a USP paddle, and the dissolution medium was chosen from pH 6.0 to pH 6.8 according to the BCS classification of compounds. The IVIVC was calculated using the Wagner-Nelson equation. The linear ranges of olmesartan, amlodipine, and hydrochlorothiazide in the plasma were 5.0-2500, 0.1-50, and 3.0-1500 ng/mL, respectively. All accuracies were within 3.8% of the target values, and the findings revealed that intra-day and inter-day accuracies were less than 12.1%. Moreover, the recoveries exceeded 88.3%, the matrix effect tests were positive, and the stability tests were positive. With the establishment of correlation, the distinguishable dissolution condition (pH 6.8) was selected as the predictable condition. The established method was suitable for the preclinical pharmacokinetic study of tripartite drugs with strong specificity and high sensitivity. Through the evaluation of IVIVC, the connection between in vivo and in vitro drug testing was initially established.

Gold nanoparticle-enhanced D-shaped optical fiber sensor for mercury ion detection.

Mercury ions (Hg2+) are highly toxic heavy metal ions that pose serious health risks to humans when present at concentrations above the safety threshold. Therefore, the development of a rapid and effective Hg2+ detection method is of significant importance. In this study, based on surface plasmon resonance (SPR) technology integrated with COMSOL simulation analysis, a highly sensitive and selective Hg2+ sensing system is constructed. Initially, gold nanoparticles and the surface of a fiber-optic gold film are modified by sodium sulfide (Na2S). In the presence of Hg2+, the sulfur ions on the modified gold film and gold nanoparticles specifically bind to Hg2+, forming the composite structure Au/S-Hg2+-S/AuNPS. Due to the strong electromagnetic coupling between the gold nanoparticles and the gold film, a significant SPR wavelength shift occurs. These results show that the Hg2+ sensor has high sensitivity and enhanced selectivity. The detection limit for mercury ions was 8.15 nM, and the recovery rate in real environmental samples was up to 90.1-97.3%. This sensing system provides an alternative method for rapid and accurate determination of mercury content.

A high sensitivity adsorptive-electrochemical method for rapid and portable determination of hydroxychloroquine

A high sensitivity adsorptive-electrochemical method for rapid and portable determination of hydroxychloroquine

Method of rapid spectrophotometric determination of iron in dithionite extracts of soils

Amethod for the determination of dithionite iron for soil samples and fractions of the order of 20–25 mg with a spectrophotometric termination has been developed and optimized.Unlike the previously described methods, phenanthroline was used as a chromogen, which made it possible to simplify the analysis by eliminating the combustion stage.The procedure for processing samples with citrate-bicarbonate-dithionite extractant has been optimized.The repeatability and intra-laboratory reproducibility of the technique are investigated.Verification of the proposed methodology by comparison with the standard one showed good convergence of the results.

Development of an electrochemical sensor based on platinum nanoparticles/iron-based metal–organic framework composite for efficient determination of butylated hydroxyanisole

Butylated hydroxyanisole (BHA), a synthetic antioxidant, is widely used in the food industry to prevent the oxidative deterioration of food products. Developing rapid, simple and sensitive methods for BHA determination is of great importance to ensure the safety and quality of food. In this study, we developed an amperometric sensor based on iron-based metal–organic framework and platinum nanoparticle modified glassy carbon electrode (PtNP/Fe-MOF/GCE) for efficient determination of BHA. The Fe-MOF was synthesized by the solvothermal method and characterized using various techniques such as powder X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. The synthesized Fe-MOF was modified onto GCE, and platinum nanoparticles were electrodeposited onto the Fe-MOF/GCE. Scanning electron microscopy and energy dispersive X-ray spectroscopy were utilized to enlighten the surface morphologies of the electrodes during the modification steps. Electrochemical characterization of the modified electrodes was performed by cyclic voltammetry and electrochemical impedance spectroscopy. Under the optimum conditions, the PtNP/Fe-MOF/GCE showed excellent electrocatalytic activity towards BHA oxidation due to its large surface area, porosity, and metal sites. The PtNP/Fe-MOF/GCE sensor exhibited a wide linear range from 6.0 × 10-8 to 5.4 × 10-5 M and a low detection limit of 9.4 × 10-9 M. The analytical applicability of the PtNP/Fe-MOF/GCE was tested by the analysis of BHA in potato chips samples.

A novel colorimetric sensor through peroxymonosulfate activated by CoFe@CN nanozymes for on-site resorcinol detection

The presence of resorcinol (RS) in water contaminated with pollutants may engender environmental and ecosystem risks. In this study, we developed rapid and efficient colorimetric methods for the on-site quantitative determination of RS. Specifically, a synthetic nanozyme composed of nitrogen-doped carbon-coated cobalt-iron (CoFe@CN) was utilized to initiate the oxidation reaction of 3,3′,5,5′-tetramethylbenzidine (TMB) with the activator of peroxymonosulfate (PMS). Compared to the activator of hydrogen peroxide (H2O2), PMS demonstrated a sixfold enhancement in catalytic efficacy, markedly elevating the detection performance. Density Functional Theory calculations indicate that RS can serve as a reducing agent for oxTMB, confirming the theoretical feasibility of this process. A linear relationship between inhibition rate (IR %) of RS concentration and absorbance was established and the colorimetric analysis revealed a linear relationship between RS concentration and gray scale values over the range of 0–45 μM, with a detection limit of 3.39 μM. Furthermore, smartphone-based analysis of color images allows for on-site quantitative analysis of RS concentration, leveraging portability and real-time detection capabilities. This study provides pioneering analytical support for on-site water quality monitoring within the ecological environment.

Chromatographic method for rapid determination of triazoles in ribavirin intermediates synthesis: stationary phase comparison

Chromatographic method for rapid determination of triazoles in ribavirin intermediates synthesis: stationary phase comparison

Development of a rapid method for determination of OchratoxinA in grape mash and wine.

The occurrence of Ochratoxin A (OTA) in wine is commonly known, but there is only limited information about its occurrence in grape mash and wines of German origin. Climate change has led to higher temperatures in the southern regions of Germany, which may increase the growth of fungi associated with the production of OTA and increase the content of this mycotoxin in grapes. A safe and rapid UHPLC-FLD method was developed and validated to assess the contamination of grape mash and wine with OTA. A total of 71 samples of grape mash and 30 wines from various wine producers in Baden-Württemberg, Germany, were analysed for OTA content. The results showed that no samples contained OTA in concentrations above the limit of detection. Further monitoring of samples from different vintages is needed.