Cyclic and open tetra-benzimidazolium sensors for dihydrogen phosphate sensing

Background: High-performance liquid chromatography (HPLC) method has been used to detect related impurities of perampanel. However, the detection of impurities is incomplete, and the limits of quantification and detection are high. A sensitive, reliable method is in badly to be developed and applied for impurity detection of perampanel bulk drug. Objective: Methodologies utilising HPLC and gas chromatography (GC) were established and validated for quantitative determination of perampanel and its related impurities (a total of 10 impurities including 2 genotoxic impurities). Methods: The separation was achieved on a Dikma Diamonsil C18 column (250 mm × 4.6 mm, 5 μm) with the mobile phase of 0.01 mol/L potassium dihydrogen phosphate solution (A) and acetonitrile (B) in gradient elution mode. The compound 2-bromopropane was determined on an Agilent DB-624 column (0.32 mm × 30 m, 1.8 μm) by electron capture detector (μ-ECD) with split injection ratio of 1:5 and proper gradient temperature program. Result: Both HPLC and GC methods were established and validated to be sensitive, accurate and robust according to International Council for Harmonization (ICH) guidelines. The methods developed were linear in the selected concentration range (R 2≥0.9944). The average recovery of all impurities was between 92.6% and 103.3%. The possible production mechanism of impurities during the synthesis and degradation processes of perampanel bulk drug was also discussed. Five impurities were analyzed by liquid chromatography–mass spectrometry (LC-MS). Moreover, two of them were simultaneously characterized by LC-MS, IR and NMR. Conclusion: The HPLC and GC methods were developed and optimized, which could be applied for quantitative detection of the impurities, and further stability study of perampanel.

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Further insights on the Thermal degradation of aluminum metaphosphate prepared from aluminum dihydrogen phosphate solution

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2021.03.023 ◽

2021 ◽

Author(s):

Guillaume Rousseau ◽

Lionel Montagne ◽

François O. Méar

Keyword(s):

Thermal Degradation ◽

Dihydrogen Phosphate ◽

Phosphate Solution

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Optical Absorption Spectra of Vanadyl Ion (Impurities) in Three Host Crystal Compounds

Zeitschrift für Naturforschung A ◽

10.1515/zna-1985-1116 ◽

1985 ◽

Vol 40 (11) ◽

pp. 1164-1166

Author(s):

O. P. Agarwal ◽

Prem Chand

Keyword(s):

Optical Absorption ◽

Potassium Dihydrogen Phosphate ◽

Optical Data ◽

Dihydrogen Phosphate ◽

Host Crystal ◽

Optical Absorption Study ◽

Potassium Dihydrogen ◽

Vanadyl Complexes ◽

Vanadyl Ion ◽

Magnesium Ammonium

Results of the optical absorption study of vanadyl ion doped in magnesium ammonium sulphate hexahydrate, rubidium sulphate and potassium dihydrogen phosphate single crystals at RT are reported. The nature of optical bands suggests a C4v symmetry of the Vanadyl complexes in conformity with the EPR results. Powder EPR data and optical data are correlated to obtain the MO coefficients.

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Ionic Liquid-Assisted Synthesis of Ag3PO4 Spheres for Boosting Photodegradation Activity under Visible Light

Catalysts ◽

10.3390/catal11070788 ◽

2021 ◽

Vol 11 (7) ◽

pp. 788

Author(s):

Beibei Zhang ◽

Lu Zhang ◽

Yulong Zhang ◽

Chao Liu ◽

Jiexiang Xia ◽

...

Keyword(s):

Ionic Liquid ◽

Visible Light ◽

High Efficiency ◽

Chemical Precipitation ◽

Active Species ◽

Precipitation Method ◽

Dihydrogen Phosphate ◽

Xrd Pattern ◽

Simple Chemical ◽

Visible Light Driven

In this work, a simple chemical precipitation method was employed to prepare spherical-like Ag3PO4 material (IL-Ag3PO4) with exposed {111} facet in the presence of reactive ionic liquid 1-butyl-3-methylimidazole dihydrogen phosphate ([Omim]H2PO4). The crystal structure, microstructure, optical properties, and visible-light photocatalytic performance of as-prepared materials were studied in detail. The addition of ionic liquids played a crucial role in forming spherical-like morphology of IL-Ag3PO4 sample. Compared with traditional Ag3PO4 material, the intensity ratio of {222}/{200} facets in XRD pattern of IL-Ag3PO4 was significantly enhanced, indicating the main {111} facets exposed on the surface of IL-Ag3PO4 sample. The presence of exposed {111} facet was advantageous for facilitating the charge carrier transfer and separation. The light-harvesting capacity of IL-Ag3PO4 was larger than that of Ag3PO4. The photocatalytic activity of samples was evaluated by degrading rhodamine B (RhB) and p-chlorophenol (4-CP) under visible light. The photodegradation efficiencies of IL-Ag3PO4 were 1.94 and 2.45 times higher than that of Ag3PO4 for RhB and 4-CP removal, respectively, attributing to a synergy from the exposed {111} facet and enhanced photoabsorption. Based on active species capturing experiments, holes (h+), and superoxide radical (•O2−) were the main active species for visible-light-driven RhB photodegradation. This study will provide a promising prospect for designing and synthesizing ionic liquid-assisted photocatalysts with a high efficiency.

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Structural, thermal and electrical properties of composites electrolytes (1−x) CsH2PO4/x ZrO2 (0 ≤ x ≤ 0.4) for fuel cell with advanced electrode

SN Applied Sciences ◽

10.1007/s42452-020-04097-9 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Deshraj Singh ◽

Pawan Kumar ◽

Jitendra Singh ◽

Dharm Veer ◽

Aravind Kumar ◽

...

Keyword(s):

Fuel Cell ◽

Solid Acid ◽

Thermal Characterization ◽

Dihydrogen Phosphate ◽

Conducting Material ◽

Scanning Calorimetry ◽

Milling Method ◽

Thermal And Electrical Properties ◽

Properties Of Composites

AbstractComposites proton conducting material based on cesium dihydrogen phosphate (CDP) doped with zirconium oxide (1−x) CsH2PO4/x ZrO2 were synthesized with different concentration having in the range such as x = 0.1, 0.2, 0.3 and 0.4 by ball milling method. The prepared solid acid composites were dried at 150 °C for 6 h. Structural and thermal characterization of solid acid composite proton electrolytes were carried out by X-ray diffractometer, Fourier transform infrared spectroscopy, and Raman spectroscopy respectively. Phase transition of the prepared materials was carried out by using differential scanning calorimetry and conductivity was measured by LC Impedance meter in the range 1 Hz to 400 kHz. The ionic conductivity of ZrO2 doped CsH2PO4 (CDP) was increased up to 1.3 × 10–2 S cm−1 at the 280 °C under environment atmospheric humidification which showed high stability as compared to pure CsH2PO4 (CDP). This obtaining result would be useful for establishing and design the next generation fuel cell.

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Validated Simultaneous Gradient Ultra-Performance Liquid Chromatographic Quantification of Some Proton Pump Inhibitor Drug Residues in Saudi Pharmaceutical Industrial Wastewater

Molecules ◽

10.3390/molecules26144358 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4358

Author(s):

Sherif A. Abdel-Gawad ◽

Hany H. Arab ◽

Alhumaidi B. Alabbas

Keyword(s):

Proton Pump ◽

Industrial Wastewater ◽

Mobile Phase ◽

Solid Phase ◽

Potassium Dihydrogen Phosphate ◽

Ultra Performance Liquid Chromatography ◽

Dihydrogen Phosphate ◽

Separation Pattern ◽

Inhibitor Drug ◽

Wastewater Samples

Monitoring and quantification of active pharmaceutical ingredients (APIs) in the environment constitute important and challenging tasks, as they are directly associated with human health. Three commonly used proton pump inhibitors (PPIs), namely, omeprazole sodium (OMP), pantoprazole sodium (PNT), and lansoprazole sodium (LNZ) are well separated and quantified using ultra-performance liquid chromatography (UPLC) in pharmaceutical industrial wastewater. The separation of the studied drugs was performed on a stationary phase with a WatersTM column (100 × 2.1 mm, 1.7 µm). The mobile phase was composed of methanol:0.05 M potassium dihydrogen phosphate buffer (adjusted to pH 7.5 using NaOH) (50:50, v/v). The elution process was done in gradient mode by changing the relative proportions of the mobile phase components with time to get an optimum separation pattern. The flow rate of the developing system was adjusted to 0.8 mL/minute. Detection of the separated drugs was performed at 230 nm. The studied drugs were quantified in the concentration range of 10–200 ng/mL for all drugs. The cited method was fully validated according to the international conference on harmonization (ICH-Q2B) guidelines, then it was applied successfully for quantification of the studied PPIs in real wastewater samples after their solid phase extraction (SPE).

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