Detection Of Ions Research Articles

UPLC-MS/MS analysis of axitinib and pharmacokinetic application in beagle dogs

ObjectiveTo develop a method for determining the concentration of axitinib in beagle dog plasma and utilize this method to investigate the pharmacokinetics of orally administered axitinib in beagle dogs. MethodsPlasma samples were processed using acetonitrile precipitation and analyzed by UPLC-MS/MS with sunitinib as an internal standard (IS). Chromatographic separation was achieved on a Waters Acquisition UPLC BEH C18 column (50 mm × 2.1 mm, 1.7 μm) with a gradient elution of acetonitrile and 0.1 % formic acid. Mass spectrometry uses an electrospray ion source for positive ion detection in a multiple reaction monitoring mode. The monitored ion transitions for axitinib and sunitinib were m/z 387 → 355.96 and m/z 399.3 → 282.96, respectively. Six beagle dogs were administered 0.33 mg/kg of axitinib orally, and venous blood samples were collected at 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, and 24 h post-dose for pharmacokinetic analysis. ResultsThe assay demonstrated a linear range of 0.5–100 ng/mL (r2 = 0.9992), and the lower limit of quantification was up to 0.5 ng/mL. Precision, as assessed by relative standard deviation (RSD), was within 8.64 % for both intraday and interday variability. The relative error (RE) for precision from −2.77 %–1.20 %. The recovery rate of the analytes exceeded 85.28 % and the matrix effect was approximately 100 %. Plasma samples maintained stability under various conditions, including room temperature storage for 12 h, processed on an automatic sampler at 4 °C for 6 h, three freeze-thaw cycles, and long-term storage at −80 °C for 60 days. Pharmacokinetic parameters were determined using DAS 2.0 software, revealing a half-life (T1/2) of 6.05 h and an area under the curve (AUC (0 →∞)) of 97.13 ng h/mL for axitinib. ConclusionsThe UPLC-MS/MS method developed in this study offers high specificity, rapid analysis, high recovery, excellent linearity, and minimal plasma volume requirements, making it well-suited for pharmacokinetic and drug interaction studies in beagles dogs.

Switching Photoluminescence “On‐Off‐On” for Detection of Chromium (VI) Ion and Ascorbic Acid with N,S‐Codoped Carbon Dots

AbstractA photoluminescent‐based “Turn On → Off → On” technique was adopted for a toxic, heavy metal ion detection, that is, specifically chromium (VI) and a pharmaceutically relevant ascorbic acid molecule. Metal‐free, environmentally benign, and fluorescent carbon dots, a potential vehicle for spectrofluorometric detection, were successfully deployed as sensors. Carbon dots synthesized from citric acid and sulfanilamide conserve the fragments of the precursor molecule on the surface. Zeta potential measurement evidenced the positively charged carbon nanoparticles physically interact with the Cr(VI)/Cr2O72− in acidic pH, resulting in a remarkable quenching in net fluorescence. Thorough studies revealed that the static quenching and inner filter effect were responsible for the reduction in fluorescence intensity. We have demonstrated a new rapid (in seconds) detection platform for Cr(VI) and ascorbic acid.

Dual-color fluorescent multi-component hybrid materials for copper ion detection, NADH regeneration and cell imaging

Gold nanoclusters (AuNCs) exhibit unique physical, chemical and photoelectric properties with various advantages. On the other hand, small organic fluorescent molecules show alternative specialized characteristics. To overcome their weaknesses and integrate strengths, we propose here a workable platform to fabricate protein-gold-dye multifunctional hybrid materials. Briefly, protein skeleton bovine serum albumin (BSA), AuNCs, and organic molecule dye Thioflavin T (ThT) are co-assembled mutually to form a dual-color fluorescent material BSA-AuNCs@ThT. This approach is simple, cost-effective, green and environmental friendly. To tackle their biological application, we coat BSA-AuNCs@ThT with cationic polyethyleneimine (PEI). The prepared BSA-AuNCs@ThT@PEI hybrid materials can be used to fluorescence imaging of microbial cells as well as HeLa cells. Due to the unique background of BSA-AuNCs@ThT@PEI, the hybrid materials work well in differentiate heavy metal ions such as Hg2+ and Cu2+ ions. Moreover, this system is also suitable to do the photocatalytic transformation and regeneration of coenzyme NADH. Therefore, we propose this platform to build new nano-dye hybrid materials for copper ion detection, NADH regeneration and cell imaging, or potentially other applications.

A ZnO-nanorod/PEDOT:PSS nanocomposite functionalized bridge-like membrane type nanomechanical sensing device for ultrasensitive blood lead detection

Lead (Pb) ion detection poses a critical problem, particularly in environmental monitoring, industrial operations, and public health, especially for young children and expecting women. Determining lead levels in blood early on is essential to minimizing the long-term consequences of lead exposure. Several sophisticated detection instruments, such as mass spectrometers which perform with high sensitivity, specificity and accuracy, but require a lab-based setting, multi-step sample preparation, expensive payment and professional operation. It is evident that a highly sensitive, portable, low-cost, quick sample-to-result, blood lead detection device that can be tested at the point-of-care is necessary. Consequently, we developed a unique ZnO/PEDOT:PSS nanocomposite layer integrated with a CMOS MEMS-based bridge-like membrane-type (BM) nanomechanical sensor for detecting lead levels in blood. PEDOT:PSS was combined with ZnO nanorods to increase lead ion binding. The sensor responds seven times better to lead ions using nanorods in the detecting layer. A linear resistance change rate response was found from 0.005 to 10 ppm, with the limit of detection (LOD) of 0.12 ppb. Similarly, our BM nanomechanical sensor can correctly assess Pb2+ in human serum with recovery rates of 86.25-150%. Measurements of human blood samples from patients with varying lead ion concentrations validated by the standard AAS show a good linear connection with the BM nanomechanical sensors' concentration, with a regression coefficient of 0.92. This describes the first micromachined nanoachanical sensing system for detection of Pb2+ in only 5 μL of human serum sample. The device achieves a time-to-result of less than 10 min. The system is designed to be very sensitive and offers affordable, disposable sensing chips together with a portable signal acquisition platform.

One-step preparation of orange-red Emitting carbon dots for visual detection of copper ions in the water environment

In this study, p-aminophenol and o-phenylenediamine were used as materials in a straightforward one-step hot solvent approach for generating a nitrogen-doped carbon dot. Fourier Transform Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and UV–Vis analysis were used to analyze the resultant CDs composites. Furthermore, fluorescence and absorption spectroscopy were used to assess the optical characteristics. Following the addition of Cu2+, CDs’ fluorescence was quenched statically, resulting in the formation of a non-fluorescent complex. Based on this, a highly selective fluorescent technique was developed with a detection limit of 2.71 μM and a relevant linear range of 10–100 μM for Cu2+. More convenient to carry and detect sodium alginate gel beads doped with carbon dots were prepared for visual detection of Cu2+. Using this method, Cu2+ ions from various environmental sources can be detected rapidly, cheaply, environmentally friendly, and selectively.

Eco-friendly and low-cost heavy metal ion detection via droplet-generated triboelectricity

TENGs (triboelectric nanogenerators)-based droplet energy harvesting is a new technology that inspired the scientific community for its low cost and flexible operation as portable sensors in many real-life applications for detecting water pollutants, microplastics, sediment, and acidity. Here, we have described a droplet-driven TENG (DD-TENG) that can detect the concentration of different heavy metal ions by generating proportional triboelectric signals. The device shows excellent sensitivity in lower concentration levels (0.01 g/L - 0.1 g/L) and higher concentration levels (0.1 g/L - 0.51 g/L) with a response time of 16 µs. The sensor shows a very stable output of up to 3500 s of operation and a detection efficiency of up to 91 %. The low-cost and environmentally friendly operation of the device can be an excellent way to detect heavy metal ions effectively. The real-time monitoring capability can pave a new technological evolution in heavy metal ion detection technology in the future.

A mixed Ce/Eu metal-organic framework for ratiometric detection of Al3+ ion.

As a heavy metal ion, excessive aluminum ions pose a serious threat to human health and the ecological environment. Developing a simple, efficient, and fast detection method to detect the content of aluminum ions is of great significance, especially for ensuring human health and ecological safety. Herein, the mixed rare earth metal-organic framework (Ce0.74Eu0.26TPTC and Ce0.62Eu0.38TPTC) were prepared based on simple ligand 1,1':4',1″-Terphenyl-2',4,4″,5'-tetracarboxylic acid (H4TPTC). The Ce0.74Eu0.26TPTC and Ce0.62Eu0.38TPTC have dual luminescence centers, which can be used as ratio fluorescent probes to detect Al3+ ions, making the detection results more accurate and reliable. Therefore, this work can promote the further development of rare earth-based MOFs in the detection of heavy metal ions.

High sensitivity fiber optic SPR sensor for selenium ion concentration detection

Balance of selenium content is of great significance to human health, and there is a need for rapid and sensitive detection of selenium ion concentrations in the human body and food. This article proposes a highly sensitive fiber surface plasmon resonance (SPR) sensor for selenium ion concentration detection. By fabricating a fiber U-shaped ring composite structure and modifying Cu3VSe4 material, the sensitivity of the fiber SPR sensor is improved to 6826.82 nm/RIU. Using 2,4-diamino-6phenyl-1,3,5-triazine to modify the surface of the sensor to achieve specific detection of selenium ion concentration. The experiment results indicate that the detection sensitivity of the sensor is 1.858 nm/(lg(pg/ml)) with range of 100 pg/ml to 1 μg/ml, and the LOD is 124.06 pg/ml. The highly sensitive SPR sensor proposed in this article, without labeling, can achieve high sensitivity and rapid detection of selenium ions, providing a new approach for trace element content detection.

Adsorption and detection of praseodymium ion by ion-imprinted polymer with ultra-low sensitivity.

A novel kind of carbon dot (CD) was prepared by one-step hydrothermal microwave assisted method using L-tryptophan and L-tartaric acid as raw materials. Monodisperse poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) microspheres were utilized as the matrix, with praseodymium (Pr) ion (Pr3+) as the template, methacrylic acid as the functional monomer, and 5-amino-8-hydroxyquinoline (5-AHQ) acts as the ligand. A composite microsphere of ion-imprinted polymer (IIP) and CD (noted CD@IIP) was prepared by surface-initiated atom transfer radical polymerization (SI-ATRP). For comparison, IIP without CD (Pr-IIP) and non-imprinted polymer (NIP) were also prepared. Through static adsorption experiments, it was determined that the saturated adsorption amount of CD@IIP is 47.19mgg-1, that of Pr-IIP is 54.49mgg-1, while that of NIP is only 24.32mgg-1. Dynamic adsorption experiments showed that the equilibrium of three kinds of materials wasreached within 30min. Particularly, CD@IIP could emit two fluorescence peaks at 325nm and 421nm under ultraviolet irradiation, and exhibited excellent selectivity and fluorescence quenching effect on Pr3+. The fluorescence response of Pr3+ in the range 0-400μmol L-1 was determined by ratiometric fluorescence method, offering a two-stage model and robust linear regression coefficient. These results demonstrated that CD@IIP exhibited selective adsorption ability for Pr3+, and a sensitive, rapid and simple method for detection of Pr3+ was successfully developed.

Triazine‐Based Molecules for Metal Ion Detection: A Decade of Advances

Triazine‐Based Molecules for Metal Ion Detection: A Decade of Advances

A pyrene-based hydrogen-bonded framework with excimer induced ratiometric emission for discriminative luminescence detection of metal ions

Discriminatory fluorescence detection of various metal ions is of significant importance in environmental and health-related applications. A luminescent hydrogen-bonded organic framework (HOF) material, PFC-1 was synthesized using 1,3,6,8-tetra(4-carboxylbenzene) pyrene (H4TBAPy) as the organic building block. The fluorescence behavior of PFC-1 is influenced by the concentration of the suspension, demonstrating different emissions characteristic of monomer and excimer fluorescence, which are highly sensitive to the surrounding environment. This allows for the potential differentiation and sensing of different target analytes. PFC-1 showed discriminatory fluorescence sensing performance towards metal ions such as Al3+, Sc3+, Cr3+, and Cu2+, with changes in fluorescence intensity, emission peak shifts, and intensity ratio changes between monomer and excimer emissions. Furthermore, a smartphone-based detection strategy was proposed, leveraging color recognition capabilities of smartphones for onsite and real-time sensing. The work demonstrate that PFC-1 is a promising material for the development of portable, cost-effective fluorescent sensors for onsite and real-time detection of metal ions. The integration of PFC-1 with smartphone technology paves the way for practical applications in environmental monitoring, industrial processes, and healthcare diagnostics.

Phosphate Ion-Selective Electrode Based on Electrochemically Modified Iron.

The significance of the detection of phosphate ions is immense in the realms of chemistry, biology, medicine, environment, and industry. The detection of phosphate ions is currently mainly reliant on blue molybdenum colorimetry, which is accurate but requires sample pretreatment, intricate operation, and a high price tag. Consequently, it is essential to create a sensor with superior efficiency, precision, straightforward functioning, and instantaneous online detection. This study has designed and created an electrochemical modification based on an iron metal electrode for this purpose. Cyclic voltammetry was used to initially ascertain the potential (-0.57 V) necessary for constant potential electrolysis. Employing a constant potential electrolysis method, the iron oxide and its phosphate were modified onto the surface of the iron electrode to enable reaction with phosphate ions. Scanning electron microscopy and energy dispersive X-ray spectroscopy were used to characterize and analyze the morphology and elemental composition of Fe-PME, elucidating how it responds to phosphate ionation. The two-electrode system was then utilized for the evaluation of the phosphate ion response of Fe-PME at pH 4. Fe-PME's response to phosphate ions is demonstrated by the results, ranging from 10-5 to 0.1 M and with a slope of -52.8 mV dec-1. Fe-PME exhibited satisfactory results when compared to the conventional blue colorimetry of molybdenum.

A Comparative Analysis of Performance Simulation for PUI Detectors Based on Traditional Probability Model and the Vasyliunas and Siscoe Model.

In recent years, the enthusiasm for deep space missions has remained unabated, resulting in continuous advancements in the research field of space environment and particles. Many instruments carried on these missions have conducted detection of pickup ions (PUIs) in the solar system. For those instruments, simulation is an effective means and a crucial step for their performance optimization and future operation in-orbit. It holds great significance for the instrument's in-orbit performance assessment, science operation optimization, and detection efficiency enhancement. In this paper, the traditional probability model and the Vasyliunas and Siscoe (V-S) model are used to generate the PUIs, which are the input for the simulation of the PUI detector. For further analysis, the numerical results of the simulation are processed to calculate the instrument's geometric factor, mass resolution, and count rates. Then, two sets of experiments are carried out for the comparison of the traditional probability model and the V-S model. The results show that, for the simulation of the instrument in the design stage, the simulation results of the traditional probability model and the V-S model are not much different. However, for the simulation of the instrument performance in-orbit, the PUI data generated based on the V-S model gave a better result than those of the traditional probability model. This conclusion is of great significance for evaluating the detection ability of the PUI detector in future deep space explorations.

Mn-doped CsPbCl3 perovskite quantum dots: A dual-function probe for copper detection and temperature sensing

The low photoluminescence quantum yield (PLQY) of CsPbCl3 perovskite quantum dots (PQDs) poses a significant challenge to their application as ion detection probes. To address this issue, we enhanced the PLQY of CsPbCl3 PQDs through Mn doping. These enhanced PQDs were then employed as probes for the highly sensitive detection of Cu2+ ions and temperature. CsPbCl3:Mn PQDs with varying Mn/Pb ratios were synthesized via hot injection. The Mn doping introduced an emission band near 600 nm, with intensity increasing alongside doping concentration. At an Mn/Pb ratio of 2.0, the PLQY was enhanced nearly tenfold, from 5.46 % for undoped CsPbCl3 to 52.48 % for CsPbCl3:Mn. CsPbCl3:Mn PQDs with the highest PLQY were employed as luminescent probes, utilizing the fluorescence intensity ratio (FIR) technique for copper detection and temperature sensing. The experimental results demonstrated a linear relationship between the FIR and Cu2+ concentration over the range of 22.12 nM to 1600 nM, with 22.12 nM being the calculated limit of detection. Analysis of the emission spectra and fluorescence lifetimes at varying Cu2+ concentrations revealed that electron transfer from CsPbCl3 to Cu2+ induced fluorescence quenching. CsPbCl3:Mn exhibits a high relative sensitivity of 15.89 % K−1 at 298 K, along with excellent reversibility. These findings highlight the potential application of CsPbCl3:Mn PQDs in both temperature sensing and the analysis of wear metals in engine lubricating oils.

Visual and Spectrophotometric Detection of Iodide Ion by Pyridine based Silver Nanoprobe and DFT Analysis

Visual and Spectrophotometric Detection of Iodide Ion by Pyridine based Silver Nanoprobe and DFT Analysis

High-Performance Electrochemical Creatinine Sensors Based on β-Lead Dioxide/Single-Walled Carbon Nanotube Electrodes.

Creatinine is an important biomarker of kidney function and muscular metabolism. In this paper, we developed the β-lead dioxide/single-walled carbon nanotube (β-PbO2/CNT) and the β-PbO2/CNT ion-selective electrode (β-PbO2/CNT/ISE), which were used as highly sensitive potentiometric sensors for creatinine detection. The fabricated electrodes exhibited highly pH-sensitive characteristics due to the synergistic effect of the electrochemical properties of CNT and β-PbO2. Moreover, an ammonium-ion-selective membrane coating allowed the β-PbO2/CNT electrode to be NH4+-selective for direct detection of the ammonium ion. By exploiting the electrochemical characteristics of these electrodes, the creatinine assay was established through the one-step selective conversion of creatinine by creatinine deiminase, in which the OH- and NH4+ generated by the enzymatic reaction were detected using β-PbO2/CNT and β-PbO2/CNT/ISE electrodes as pH- and NH4+-responsive sensors, respectively. The total creatinine assay can be completed within ∼5 min. The assay results from β-PbO2/CNT and β-PbO2/CNT/ISE showed excellent sensitivity values of -75.56 and 64.62 mV in the detection range of 10-400 μM with a fast response (20 s), and the limits of detection were calculated to be 0.06 and 0.13 μM, respectively. Moreover, the developed creatinine sensor showed high selectivity against 11 interfering bio/chemical species with negligible interferences (selectivity coefficient <10-4) and excellent repeatability (>97% within 25 cycles) and long-term stability for 4 weeks of storage. In addition, the feasibility and practicality of the device were successfully demonstrated in human serum tests, with recoveries of 95-104% for PbO2/CNT and 92-110% for PbO2/CNT/ISE.

“Kill two birds with one stone” role of PTCA-COF: Enhanced electrochemiluminescence of Au nanoclusters via radiative transitions and electrochemical excitation for sensitive detection of cadmium ions

Au nanoclusters (AuNCs) have attracted significant attention in electrochemiluminescence (ECL) owing to their excellent luminescent properties; however, achieving high-efficient ECL remains a formidable challenge. Despite the extensively reported emphasis on enhancing radiative transitions, it is imperative to acknowledge that both radiation and excitation play crucial roles in ECL, thereby requiring a dual-enhanced strategy for improving ECL efficiency. Herein, we introduced PTCA-COF, a dual-functional covalent organic frameworks (COFs) with the effect of “kill two birds with one stone” to achieve this purpose. The PTCA-COF not only acted as a carrier to effectively suppress the rotational vibration of surface ligands and reduce self-quenching by minimizing non-radiative transitions, but also acted as an electrosensitiser that facilitated the generation of electrogenerated holes, thereby promoting efficient transfer of hot electrons and enhancing excitation of AuNCs due to favorable energy level alignment. As a proof of concept, by utilizing cadmium ions (Cd2+) as a model analyte, the ECL aptasensing platform fabricated based on the dual-enhancement AuNCs-COFs ECL system demonstrated a broad linear response spanning from 1 pM to 5 nM and achieved an impressive low detection limit of 0.66 pM (S/N=3) with exceptional reproducibility and selectivity. The findings of this study not only presented a novel approach for the rational dual-enhancement of ECL efficiency, but also contributed to the advancement of their potential applications in the field of environmental monitoring.

Novel sulfonylurea fluorescence probes for antiproliferative activity, detection and imaging of fluoride ions in living cells

In this study, four novel triphenylpyrazoline 4-toluenesulfonylureas (PYSUs) were synthesized to develop potential anticancer drugs and fluorescent probes for the detection of F− ions. The compounds were synthesized via a two-step microwave-assisted method. The antiproliferative activity of the PYSUs was tested against two cancer cell lines: HepG2 and MDA-MB-231. Among the compounds, 3a exhibited strong activity against both cell lines, while 3b showed strong activity against MDA-MB-231 cells but weaker inhibition of HepG2 cells. Furthermore, compound 3b was identified as the best fluorescent probe, with an increase in emission intensity in the presence of F− ions from tetrabutylammonium fluoride (TBAF). In DMSO, the emission wavelength was found to be 518 nm (green) with an excitation wavelength of 469 nm. The limit of detection (LOD) was calculated to be 0.269 mM in the linear range of 5–10 mM. The interaction mechanism between F− ions and compound 3b was further explored via DFT/TDDFT calculations. Additionally, fluorescent imaging of TBAF-incubated MDA-MB-231 and HepG2 cells confirmed the potential of PYSUs as fluorescent sensors for F− ions in living cancer cells.

Emerging insights into the application of metal-organic framework (MOF)-based materials for electrochemical heavy metal ion detection

Heavy metal ions are one of the main sources of water pollution, which has become a major global problem. Given the growing need for heavy metal ion detection, electrochemical sensor stands out for its high sensitivity and efficiency. Metal-organic frameworks (MOFs) have garnered much interest as electrode modifiers for electrochemical detection of heavy metal ions owing to their significant specific surface area, tailored pore size, and catalytic activity. This review summarizes the progress of MOF-based materials, including pristine MOFs and MOF composites, in the electrochemical detection of various heavy metal ions. The synthetic methods of pristine MOFs, the detection mechanisms of heavy metal ions and the modification strategies of MOFs are introduced. Besides, the diverse applications of MOF-based materials in detecting both single and multiple heavy metal ions are presented. Furthermore, we present the current challenges and prospects for MOF-based materials in electrochemical heavy metal ion detection.

Green Synthesis of Silver Nanoparticles Using Cyto-compatible Polymer Derivative of Tara Gum for Gold (III) ion Detection in Water Samples

Green Synthesis of Silver Nanoparticles Using Cyto-compatible Polymer Derivative of Tara Gum for Gold (III) ion Detection in Water Samples