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1.
Cell Rep Methods ; 4(1): 100688, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38218189

RESUMO

Single-molecule enzyme activity-based enzyme profiling (SEAP) is a methodology to globally analyze protein functions in living samples at the single-molecule level. It has been previously applied to detect functional alterations in phosphatases and glycosidases. Here, we expand the potential for activity-based biomarker discovery by developing a semi-automated synthesis platform for fluorogenic probes that can detect various peptidases and protease activities at the single-molecule level. The peptidase/protease probes were prepared on the basis of a 7-amino-4-methylcoumarin fluorophore. The introduction of a phosphonic acid to the core scaffold made the probe suitable for use in a microdevice-based assay, while phosphonic acid served as the handle for the affinity separation of the probe using Phos-tag. Using this semi-automated scheme, 48 fluorogenic probes for the single-molecule peptidase/protease activity analysis were prepared. Activity-based screening using blood samples revealed altered single-molecule activity profiles of CD13 and DPP4 in blood samples of patients with early-stage pancreatic tumors. The study shows the power of single-molecule enzyme activity screening to discover biomarkers on the basis of the functional alterations of proteins.


Assuntos
Neoplasias Pancreáticas , Peptídeo Hidrolases , Ácidos Fosforosos , Humanos , Peptídeo Hidrolases/metabolismo , Proteínas , Biomarcadores , Hormônios Pancreáticos
2.
Int J Mol Sci ; 25(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38203761

RESUMO

Lung cancer is a pervasive and challenging disease with limited treatment options, with global health challenges often present with complex molecular profiles necessitating the exploration of innovative therapeutic strategies. Single-target drugs have shown limited success due to the heterogeneity of this disease. Multitargeted drug designing is imperative to combat this complexity by simultaneously targeting multiple target proteins and pathways, which can enhance treatment efficacy and overcome resistance by addressing the dynamic nature of the disease and stopping tumour growth and spread. In this study, we performed the molecular docking studies of Drug Bank compounds with a multitargeted approach against crucial proteins of lung cancer such as heat shock protein 5 (BIP/GRP78) ATPase, myosin 9B RhoGAP, EYA2 phosphatase inhibitor, RSK4 N-terminal kinase, and collapsin response mediator protein-1 (CRMP-1) using HTVS, SP with XP algorithms, and poses were filtered using MM\GBSA which identified [3-(1-Benzyl-3-Carbamoylmethyl-2-Methyl-1h-Indol-5-Yloxy)-Propyl-]-Phosphonic Acid (3-1-BenCarMethIn YlPro-Phosphonic Acid) (DB02504) as multitargeted drug candidate with docking and MM\GBSA score ranges from -5.83 to -10.66 and -7.56 to -50.14 Kcal/mol, respectively. Further, the pharmacokinetic and QM-based DFT studies have shown complete acceptance results, and interaction fingerprinting reveals that ILE, GLY, VAL, TYR, LEU, and GLN were among the most interacting residues. The 100 ns MD simulation in the SPC water model with NPT ensemble showed stable performance with deviation and fluctuations <2 Å with huge interactions, making it a promising multitargeted drug candidate; however, experimental studies are needed before use.


Assuntos
Neoplasias Pulmonares , Ácidos Fosforosos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Simulação de Acoplamento Molecular , Adenosina Trifosfatases , Algoritmos , Chaperona BiP do Retículo Endoplasmático
3.
Int J Biol Macromol ; 260(Pt 2): 129546, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246461

RESUMO

Present investigation deals with the synthesis of psyllium based copolymeric hydrogels and evaluation of their physiochemical and biomedical properties. These copolymers have been prepared by grafting of poly(vinyl phosphonic acid) (poly (VPA)) and poly(acrylamide) (poly(AAm)) onto psyllium in the presence of crosslinker N,N-methylene bis acrylamide (NNMBA). These copolymers [psyllium-poly(VPA-co-AAm)-cl-NNMBA] were characterized by field emission-scanning electron micrographs (FE-SEM), electron dispersion X-ray analysis (EDAX), Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), 13C-nuclear magnetic resonance (NMR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA)- differential thermal analysis (DTG). FESEM, AFM and XRD demonstrated heterogeneous morphology with a rough surface and an amorphous nature. Diffusion of ornidazole occurred with a non-Fickian diffusion mechanism, and the release profile data was fitted in the Korsemeyer-Peppas kinetic model. Biochemical analysis of hydrogel properties confirmed the blood-compatible nature during blood-polymer interactions and revealed haemolysis value 3.95 ± 0.05 %. The hydrogels exhibited mucoadhesive character during biomembrane-polymer interactions and demonstrated detachment force = 99.0 ± 0.016 mN. During 2,2-diphenyl-1-picrylhydrazyl reagent (DPPH) assay, free radical scavenging was observed 37.83 ± 3.64 % which illustrated antioxidant properties of hydrogels. Physiological and biomedical properties revealed that these hydrogels could be explored for drug delivery uses.


Assuntos
Acrilamida , Ácidos Fosforosos , Psyllium , Acrilamida/química , Psyllium/química , Hidrogéis/química , Acrilamidas/química , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Concentração de Íons de Hidrogênio
4.
Int J Mol Sci ; 24(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37894769

RESUMO

Immune checkpoint inhibitor therapy targeting the PD-1/PD-L1 axis in cancer patients, is a promising oncological treatment. However, the number of non-responders remains high, causing a burden for the patient and the healthcare system. Consequently, a diagnostic tool to predict treatment outcomes would help with patient stratification. Molecular imaging provides said diagnostic tool by offering a whole-body quantitative assessment of PD-L1 expression, hence supporting therapy decisions. Four PD-L1 radioligand candidates containing a linker-chelator system for radiometalation, along with three hydrophilizing units-one sulfonic and two phosphonic acids-were synthesized. After labeling with 64Cu, log D7.4 values of less than -3.03 were determined and proteolytic stability confirmed over 94% intact compound after 48 h. Binding affinity was determined using two different assays, revealing high affinities up to 13 nM. µPET/CT imaging was performed in tumor-bearing mice to investigate PD-L1-specific tumor uptake and the pharmacokinetic profile of radioligands. These results yielded an unexpected in vivo distribution, such as low tumor uptake in PD-L1 positive tumors, high liver uptake, and accumulation in bone/bone marrow and potentially synovial spaces. These effects are likely caused by Ca2+-affinity and/or binding to macrophages. Despite phosphonic acids providing high water solubility, their incorporation must be carefully considered to avoid compromising the pharmacokinetic behavior of radioligands.


Assuntos
Neoplasias , Tomografia por Emissão de Pósitrons , Humanos , Animais , Camundongos , Tomografia por Emissão de Pósitrons/métodos , Ácidos Fosforosos , Antígeno B7-H1/metabolismo , Compostos Radiofarmacêuticos/metabolismo , Linhagem Celular Tumoral
5.
Environ Sci Technol ; 57(30): 11032-11042, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37467139

RESUMO

As alternatives to traditional per- and polyfluoroalkyl substances, perfluoroalkyl phosphonic acids (PFPiAs) are widely present in aquatic environments and can potentially harm aquatic organisms. Pigmentation affects the probability of aquatic organisms being preyed on and serves as an important toxic endpoint of development, but little is known about the impacts of PFPiAs on the development of aquatic organisms. In this study, Xenopus laevis embryos were exposed to 6:6 PFPiA (1, 10, and 100 nM) for 14 days. The developed tadpoles exhibited evident pigmentation with increased melanin particle size and density on the skin. Pathological and behavioral experiments revealed that the retinal layers became thinner, reducing the photosensitivity and disturbing the circadian rhythm of the tadpoles. Compared to the control group, the exposed tadpoles showed higher levels but less changes of melanin throughout the light/dark cycle, as well as distinct oxidative damage. Consequently, the expression level of microphthalmia-associated transcription factor (MITF), a key factor inducing melanin synthesis, increased significantly. Molecular docking analysis suggested that 6:6 PFPiA forms strong interactions in the binding pocket of MITF, implying that it could activate MITF directly. The activation of MITF ultimately promotes melanin synthesis, resulting in pigmentation on tadpoles.


Assuntos
Fluorocarbonos , Melaninas , Melaninas/metabolismo , Ácidos Fosforosos , Simulação de Acoplamento Molecular , Pigmentação
6.
Chemistry ; 29(72): e202302171, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-37461839

RESUMO

α-Aminophosphonic acids have a remarkably broad bioactivity spectrum. They can function as highly efficient transition state mimics for a variety of hydrolytic and angiotensin-converting enzymes, which makes them interesting target structures for synthetic chemists. In particular, the phosphonic acid analogs to α-aminocarboxylic acids (Pa AAs) are potent enzyme inhibitors, but many of them are only available by chiral or enzymatic resolution; sometimes only one enantiomer is accessible, and several have never been prepared in enantiopure form at all. Today, a variety of methods to access enantiopure α-aminophosphonic acids is known but none of the reported approaches can be generally applied for the synthesis of Pa AAs. Here we show that the phosphonic acid analogs of many (proteinogenic) α-amino acids become accessible by the catalytic, stereoselective asymmetric transfer hydrogenation (ATH) of α-oxo-phosphonates. The highly enantioenriched (enantiomeric excess (ee) ≥ 98 %) α-hydroxyphosphonates obtained are important pharmaceutical building blocks in themselves and could be easily converted to α-aminophosphonic acids in most studied cases. Even stereoselectively deuterated analogs became easily accessible from the same α-oxo-phosphonates using deuterated formic acid (DCO2 H).


Assuntos
Organofosfonatos , Ácidos Fosforosos , Hidrogenação , Estrutura Molecular , Ácidos Fosforosos/química , Organofosfonatos/química , Estereoisomerismo
7.
Chemosphere ; 322: 138122, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36775037

RESUMO

Soil washing is a rapid and efficient method for heavy metals removal. In this study, a kind of novel environmentally friendly eluent is proposed, consisting of ethylenediamine tetra methylene phosphonic acid and saponin (E-S). In a response surface optimization design (RSOD), the operating parameters were optimized and ecological effects were investigated. Additionally, soil microbial diversity and composition were discussed. Finally, an optimal method for chelator recovery was presented. The single-factor and RSOD results showed that E-S had higher remediation efficiency for Pb-Cd contaminated soil with the best parameters of duration 240 min, temperature 40 °C, E/S ratio 1:1. Under these operating conditions, the removal rates of Pb and Cd were (72.2 ± 0.5)% and (61.2 ± 0.4)% for the artificially contaminated soil and (69.2 ± 0.1)% and (65.2 ± 0.2)% for in situ contaminated soil, respectively. The contents of Pb and Cd decreased from 562.36 mg/kg to 180.41 mg/kg and 80.96 mg/kg to 27.2 mg/kg respectively, and the soil ecological risk indexes reduced from 32% to 24% for Pb and 36%-27% for Cd. Owing to the efficient enrichment of Stenotrophomonas in soil, E-S has a potential of simultaneous removal effect on organic pollutants as well. Furthermore, the results revealed that E-S can be effectively recovered (>95%) by sodium sulfide precipitation.


Assuntos
Recuperação e Remediação Ambiental , Metais Pesados , Saponinas , Poluentes do Solo , Cádmio , Chumbo , Ácidos Fosforosos , Solo , Poluentes do Solo/análise , Metais Pesados/análise
8.
Environ Sci Technol ; 57(2): 1028-1038, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36594808

RESUMO

As alternatives to traditional per- and polyfluoroalkyl substances, perfluoroalkyl phosphonic acids (PFPiAs) are frequently detected in aquatic environments, but the neurotoxic effects and underlying mechanisms remain unclear. In this study, male zebrafish were exposed to 6:6 PFPiA (1 and 10 nM) for 28 days, which exhibited anxiety-like symptoms. Gut microbiome results indicated that 6:6 PFPiA significantly increased the abundance of Gram-negative bacteria, leading to enhanced levels of lipopolysaccharide (LPS) and inflammation in the gut. The LPS was delivered to the brain through the gut-brain axis (GBA), damaged the blood-brain barrier (BBB), stimulated neuroinflammation, and caused apoptosis as well as neural injury in the brain. This mechanism was verified by the fact that antibiotics reduced the LPS levels in the gut and brain, accompanied by reduced inflammatory responses and anxiety-like behavior. The BBB damage also resulted in the enhanced accumulation of 6:6 PFPiA in the brain, where it might bind strongly with and activate aryl hydrocarbon receptor (AhR) to induce brain inflammation directly. Additionally, as the fish received treatment with an inhibitor of AhR, the inflammation response and anxiety-like behavior decreased distinctly. This study sheds light on the new mechanisms of neurotoxicity-induced 6:6 PFPiA due to the interruption on GBA.


Assuntos
Eixo Encéfalo-Intestino , Microbioma Gastrointestinal , Ácidos Fosforosos , Animais , Masculino , Inflamação , Lipopolissacarídeos , Peixe-Zebra , Ácidos Fosforosos/toxicidade
9.
Inorg Chem ; 62(3): 1218-1225, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36630536

RESUMO

The organo-functionalization of metal oxides is a key strategy to introduce new functionalities. Often, phosphonates are used to anchor organic moieties to a range of metal oxides. Despite their widespread use, there is a lack of understanding of the parameters which enable selective and efficient formation of organophosphonate-metal oxide hybrids. Here, we report fundamental insights into the mechanism of phosphonate anchoring to a molecular metal oxide model. Specifically, we use in situ 31P NMR spectroscopy to follow the acid-catalyzed deprotection of a model phosphonate and its subsequent condensation to form a phosphonate-functionalized Dawson-polyoxometalate. Our study shows that the nucleophilicity of the acid anion is a key parameter which controls the clean and selective deprotection and polyoxometalate attachment of phosphonates. This insight will allow researchers to expand the scope of phosphonate anchoring to metal oxides by enabling the development of mild and scalable syntheses.


Assuntos
Organofosfonatos , Organofosfonatos/química , Ácidos Fosforosos/química , Óxidos/química , Catálise
10.
J Biomed Mater Res B Appl Biomater ; 111(6): 1197-1206, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36715221

RESUMO

Here, surface-enhanced Raman scattering (SERS) and tip-enhanced Raman scattering (TERS) were used to characterize the selective adsorption of N-substituted 4-[(NH-R)(phosphono)-S-methyl]phenylboronic acids on the surface of platinum nanoparticles (PtNPs) from an aqueous solution and from air. The nature of the interaction of the studied compounds with the PtNPs/H2 O and PtNPs/air interfaces was discussed and compared. For this purpose, 4-[(N-anilino)(phosphono)-S-methyl]phenylboronic acid (1-PBA-PA) and its two analogs (2-PBA-PA and bis{1-PBA-PA}) as well as the PtNPs were synthesized in surfactant/ion-free solution via a synthetic route that allows control of the size and morphology of the NPs. The positively charged PtNPs with a size of ~12 nm were characterized by ultraviolet-visible spectroscopy (UV-Vis), dynamic light scattering (DLS), scanning electron microscopy (SEM), and X-ray powder diffraction (XRD).


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Organofosfonatos , Nanopartículas Metálicas/química , Ácidos Fosforosos , Análise Espectral Raman/métodos , Platina/química , Nanoestruturas/química
11.
ChemMedChem ; 18(4): e202200526, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36367256

RESUMO

Paracetamol and valproic acid are standalone drugs with leading position in the world drug market. The phosphonate analogues of these drugs were synthesized and were tested in vivo. N-(4-hydroxyphenylcarbamoyl)phosphonic acid was four times more potent than paracetamol in preventing acetic acid-induced writhing. Phosphonate derivative of valproic acid, (2-propylpentanoyl)phosphonic acid, had similar in vivo activity to valproic acid in the pentylenetetrazole-induced kindling mouse model.


Assuntos
Organofosfonatos , Ácido Valproico , Camundongos , Animais , Ácido Valproico/farmacologia , Acetaminofen/farmacologia , Organofosfonatos/farmacologia , Ácidos Fosforosos/farmacologia
12.
Sci Rep ; 12(1): 21299, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494565

RESUMO

The use of benzyl trichloroacetimidates for the benzylation of phosphonic acid nerve agent markers under neutral, basic, and slightly acidic conditions is presented. The benzyl-derived phosphonic acids were detected and analyzed by Electron Ionization Gas Chromatography-Mass Spectrometry (EI-GC-MS). The phosphonic acids used in this work included ethyl-, cyclohexyl- and pinacolyl methylphosphonic acid, first pass hydrolysis products from the nerve agents ethyl N-2-diisopropylaminoethyl methylphosphonothiolate (VX), cyclosarin (GF) and soman (GD) respectively. Optimization of reaction parameters for the benzylation included reaction time and solvent, temperature and the effect of the absence or presence of catalytic acid. The optimized conditions for the derivatization of the phosphonic acids specifically for their benzylation, included neutral as well as catalytic acid (< 5 mol%) and benzyl 2,2,2-trichloroacetimidate in excess coupled to heating the mixture to 60 °C in acetonitrile for 4 h. While the neutral conditions for the method proved to be efficient for the preparation of the p-methoxybenzyl esters of the phosphonic acids, the acid-catalyzed process appeared to provide much lower yields of the products relative to its benzyl counterpart. The method's efficiency was tested in the successful derivatization and identification of pinacolyl methylphosphonic acid (PMPA) as its benzyl ester when present at a concentration of ~ 5 µg/g in a soil matrix featured in the Organisation for the Prohibition of Chemical Weapons (OPCW) 44th proficiency test (PT). Additionally, the protocol was used in the detection and identification of PMPA when spiked at ~ 10 µg/mL concentration in a fatty acid-rich liquid matrix featured during the 38th OPCW-PT. The benzyl derivative of PMPA was partially corroborated with the instrument's internal NIST spectral library and the OPCW central analytical database (OCAD v.21_2019) but unambiguously identified through comparison with a synthesized authentic standard. The method's MDL (LOD) values for the benzyl and the p-methoxybenzyl pinacolyl methylphosphonic acids were determined to be 35 and 63 ng/mL respectively, while the method's Limit of Quantitation (LOQ) was determined to be 104 and 189 ng/mL respectively in the OPCW-PT soil matrix evaluated.


Assuntos
Substâncias para a Guerra Química , Agentes Neurotóxicos , Agentes Neurotóxicos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Fosforosos/química , Elétrons , Solo/química , Substâncias para a Guerra Química/análise
13.
Curr Opin Chem Biol ; 71: 102214, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36202046

RESUMO

The phosphonate class of natural products have received significant interests in the post-genomic era due to the relative ease with which their biosynthetic genes may be identified and the resultant final products be characterized. Recent large-scale studies of the elucidation and distributions of phosphonate pathways have provided a robust landscape for deciphering the underlying biosynthetic logic. A recurrent theme in phosphonate biosynthetic pathways is the interweaving of enzymatic reactions across different routes, which enables diversification to elaborate chemically novel scaffolds. Here, we provide a few vignettes of how Nature has utilized both convergent and divergent biosynthetic strategies to compile pathways for production of novel phosphonates. These examples illustrate how common intermediates may either be generated or intercepted to diversify chemical scaffolds and provides a starting point for both biotechnological and synthetic biological applications towards new phosphonates by similar combinatorial approaches.


Assuntos
Produtos Biológicos , Organofosfonatos , Produtos Biológicos/metabolismo , Ácidos Fosforosos , Vias Biossintéticas , Organofosfonatos/metabolismo
14.
J Dent ; 126: 104283, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36087873

RESUMO

OBJECTIVES: This review evaluated the effects of the acidic composition of self-etch (SE) adhesives at the long-term bond strengths to dentin and enamel. DATA: The review followed the PRISMA Extension Statement for network meta-analysis. Studies were identified by a systematic search in PubMed, Web of Science, and Scopus databases. STUDY SELECTION: The inclusion criteria were in vitro studies that evaluated bond strength data of samples analyzed at both immediate and long-term (after aging simulation) periods and that were bonded to sound dentin/enamel using SE adhesives, with at least one group of adhesives being based on 10-MDP (10-methacryloyloxy-decyl-dihydrogen-phosphate; control) and the other group being comprised of alternative acidic monomers. Statistical analyses were conducted using two methods: standard pairwise meta-analysis (SPMA) and Bayesian network meta-analysis (NMA). Heterogeneity was assessed by using the Cochran Q test and I2 statistics. RESULTS: From 5220 studies identified, 87 met the eligibility criteria and 83 were meta-analyzed. Seventeen adhesives were based on 10-MDP and 44 systems were based on alternative acids. The resin-dentin/enamel bonds were predominantly reduced after aging (∼84% of cases). From the SPMA findings, the following acidic compositions showed lower bond strength values (effect size: mean difference [MD] with 95% confidence interval [95% CI]) than 10-MDP: 4-META (MD -4.99, 95% CI: -7.21, -2.78; p<0.001); sulfonic acids (MD -9.59, 95% CI -12.19, -6.98; p<0.001); unspecified phosphate esters (MD -8.89, 95% CI -17.50, -0.28; p = 0.04); or mixed acids (MD -11.0, 95% CI -13.62, -8.38; p<0.001). The dental bonds were benefited from the presence of 10-MDP upon longer aging (>6 months). From the NMA probabilistic findings, adhesives based on 10-MDP and phosphonic acids ranked as having the best and the worst bonding potential to dentin, respectively. More than one composition (phosphonic acids and mixed acids) ranked similarly to 10-MDP in enamel. The studies scored as having moderate risk of bias (58.6%), followed by low (39.1%) and high (2.3%) risk of bias. CONCLUSION: 10-MDP is an outstanding acidic monomer that contributes to higher bonds to dentin at the long-term. In enamel, there is no evidence that one acidic composition prevails over the other. CLINICAL SIGNIFICANCE: The acidic composition of SE adhesives affects the resistance of dental bonds after simulated aging, with 10-MDP playing a significant role in the adhesion to dentin but not to the enamel. REGISTRATION NUMBER: This report is registered at the Open Science Framework (osf.io/urtdf).


Assuntos
Colagem Dentária , Adesivos Dentinários , Adesivos Dentinários/química , Cimentos de Resina/química , Dentina/química , Cimentos Dentários , Metanálise em Rede , Ácidos Fosforosos/análise , Teorema de Bayes , Teste de Materiais , Ácidos Sulfônicos/análise , Fosfatos
15.
Appl Radiat Isot ; 188: 110386, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35939938

RESUMO

153Sm-EDTMP is widely used as a palliative radiopharmaceutical for treatment of metastatic bone pain. It is produced by neutron activation of enriched 152Sm targets in a nuclear reactor. The long-lived europium radionuclides are co-produced along with production of 153Sm and it give rise to radioactive waste in 153Sm-EDTMP production. The gamma radiation dose rate was found significant on the radioactive waste generated during the production of 153Sm-EDTMP. Residual activity in six waste samples generated in different batches of 153Sm-EDTMP production were analysed for percentage contributions of 152,154,155Eu using gamma-ray spectrometry. 154Eu was a major contributor with around 62%, and the other radioisotopes, viz. 152Eu &155Eu contribution were ∼29% & ∼9% respectively. The activity concentration of these long-lived europium radionuclides in samarium radiopharmaceutical production waste may be utilised for the dose rate estimation, and vice versa.


Assuntos
Neoplasias Ósseas , Compostos Organometálicos , Resíduos Radioativos , Neoplasias Ósseas/secundário , Etilenos , Európio/química , Humanos , Compostos Organometálicos/uso terapêutico , Compostos Organofosforados/química , Ácidos Fosforosos , Radioisótopos/química , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/uso terapêutico , Samário/uso terapêutico
16.
J Agric Food Chem ; 70(33): 10349-10358, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35947784

RESUMO

Potassium dihydrogen phosphonate had been allowed as a plant strengthener in organic viticulture in the European Union only until 2013, supporting the control of grapevine downy mildew. Therefore, low or nondetectable levels are a prerequisite for marketing of organic wines and, consequently, validated analytical methods are of major interest. Herein, two methods based on ion chromatography conductivity detection (IC-CD) or ion chromatography inductively coupled plasma mass spectrometry (IC-ICP-MS) for the determination of phosphonic acid (H3PO3) from 14 different plant matrices of Vitis vinifera L., wine, and soil were developed, validated, and compared. Extraction recoveries ranged from 95.1 to 99.3%. Limits of quantification (LOQ) ranged in liquid and solid samples from 3.8 to 16.8 µg/kg and 0.08 to 2.41 mg/kg for ICP-MS detection and from 39.9 to 593.7 µg/kg and 3.51 to 58.7 mg/kg for CD, respectively. Data on a current anonymized selection of 100 conventionally and 30 organically produced wines are briefly presented to demonstrate the suitability of the method.


Assuntos
Vinho , Cromatografia/métodos , Íons , Espectrometria de Massas/métodos , Ácidos Fosforosos , Solo , Vinho/análise
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 281: 121623, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35872426

RESUMO

Diethylenetriamine pentamethylene phosphonic acid (DTPMP) is one of the most commonly used amino organic phosphonates. The existing methods for DTPMP detection are complicated, time-consuming, and cannot detect trace DTPMP in the natural environment. In the present work, the Fe-based 3,5-dimethyl pyrazole fluorescent sensor (Fe-DP) was constructed. The addition of Fe3+ to DP solution can greatly decrease the fluorescent intensity of DP, while the addition of different concentrations of DTPMP will restore the fluorescence intensity of DP to different degrees, to achieve quantitative detection of DTPMP, and the detection limit (LOD) of DTPMP was lower as 0.105 µΜ. The Fe-DP fluorescent sensor exhibited excellent anti-interference ability and good stability. Moreover, the fluorescence quenching mechanism of DP by Fe3+ was revealed by UV absorption spectrum and Multiwfn wavefunction analysis based on density function theory (DFT). The results revealed that the excitation of DP belonged to local excitation, in which the electrons were donated primarily by the N atom with double bond and redistributed within the pyrazole ring.The fluorescence quenching of adding Fe3+ was not caused by resonance energy transfer or charge transfer, which did not belong to dynamic quenching, but due to the ground state complex formed by the coordination of Fe3+ and the double bond N atom on the DP pyrazole ring.


Assuntos
Corantes Fluorescentes , Poliaminas , Corantes Fluorescentes/química , Ácidos Fosforosos , Pirazóis
18.
FEMS Microbiol Lett ; 369(1)2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35906193

RESUMO

Phosphonic acid (phosphonate) that possesses a carbon-phosphours bond is a chemically stable form of organic phosphorus. Various phosphonic acids are widely distributed in oceanic waters; in particular, methylphosphonic acid (namely methylphosphonate) is believed to be responsible for global methane production. To discuss the microbial degradation of phosphonic acids, we investigated the utilization of phosphonic acid compounds by cultures of marine bacteria, Phaeobacter sp., Ruegeria sp. (Rhodobacterales), and Thalassospira sp. (Rhodospirillales). These bacterial cultures were able to grow on methylphosphonic acid as well as on the tested alkyl-, carboxy-, aminoalkyl-, and hydroxyalkyl-phosphonic acid compounds. Cell yields and growth rates of Ruegeria and Thalassospira cultures grown on methyl-, ethyl-, propyl-, and butyl-phosphonic acid compounds tended to decrease with increasing alkyl chain length. In contrast, Phaeobacter sp. grew well on such alkyl-phosphonic acids. Our results suggest that these marine bacteria, which exhibit varied utilization, are involved in microbial degradation of various phosphonic acid compounds.


Assuntos
Ácidos Fosforosos , Rhodobacteraceae , Oceanos e Mares , Fósforo
19.
Phys Chem Chem Phys ; 24(18): 11362-11369, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35502624

RESUMO

The structure of intermolecular hydrogen-bonded complexes formed between tert-butylphosphonic acid and trimethylpyridine molecules has been experimentally studied as the simplest model system of the structural motifs in blend proton-conducting polymer membranes based on phosphonic acid residues. The stoichiometry of the formed complexes and proton positions in OHO and OHN hydrogen bonds were established by the H/D isotope effects and temperature dependences of the signals in 1H and 31P NMR spectra. Two structural motifs, namely, 1 : 2 and 2 : 2 acid-base complexes, were identified at the low temperature in a polar aprotic environment. In the 1 : 2 complex, one proton has passed through the hydrogen bond center creating a chain of two cooperatively coupled OHN bonds, while in the 2 : 2 complex both OHN bonds are zwitterionic and anti-cooperatively coupled to each other via a dianionic cyclic dimer of phosphonic acid in the middle. The dianionic cyclic dimer is metastable by itself, but under the used experimental conditions it is stabilized by complexation with two trimethylpyridinium cations. Additionally, quantum chemical calculations using the DFT method were carried out to support the experimental data.


Assuntos
Polímeros , Prótons , Ácidos , Ânions , Ligação de Hidrogênio , Ácidos Fosforosos
20.
J Fluoresc ; 32(3): 983-992, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35230565

RESUMO

Chirality plays a pivotal role in drugs, agrochemicals and food additives et al. The enantiomers of a chiral molecule often show huge difference in bioactivity, metabolism, and toxicity et al. thereby, the recognition of chiral molecules shows an increasingly important priority. In this paper, a novel method for chiral fluorescence recognition based on anthracene fluorescent dyes (AD) ⊂ water-soluble pillar[5] arene containing phosphonic acid group (PWP[5]) is developed. The AD as guest molecule can complex with PWP [5] to form 1:1 AD ⊂ PWP[5] assembly, and this assembly can be further used as a fluorescent probe to identify D/L-phenylalanine and D/L-phenylalaninol by fluorescent titration. The fluorescence intensity of the assembly was significantly reduced for D-phenylalanine and D-phenylalaninol, while L-phenylalanine or L-phenylalaninol was added to AD ⊂ PWP[5] assembly, the fluorescence intensity of the assembly almost unchanged. Hence, the chiral recognition based on assembly between the achiral fused ring fluorescent dye and achiral PWP[5] was developed.


Assuntos
Calixarenos/química , Corantes Fluorescentes , Compostos de Amônio Quaternário/química , Água , Antracenos , Fluorescência , Corantes Fluorescentes/química , Fenilalanina , Ácidos Fosforosos
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