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1.
Chemosphere ; 361: 142522, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838869

RESUMO

Selecting safe, non-toxic, and non-metallic semiconductor materials that facilitate the degradation of pollutants in water stands out as an optimal approach to combat environmental pollution. Herein, graphitic carbon nitride (g-C3N4)-based hollow nanospheres nonmetallic photocatalyst modified with covalent organic framework materials named TpMA, based on 1, 3, 5-trimethylchloroglucuronide (Tp) and melamine (MA), was successfully synthesized (abbreviated as CNTP). The ordered electron donor-acceptor structure inherent in TpMA contributed to enhancing the transport efficiency of photogenerated carriers in CNTP. The CNTP photocatalysts exhibited excellent performance in degrading rhodamine B and tetracycline in visible light, with optimal degradation rates reached more than 90% in 60 and 80 min, respectively, which were 5.3 and 3.0 times higher than those of pure CNNS. The increased photocatalytic efficiency observed in CNTP composites could be traced back to the covalently connection between the two molecules, forming a π-conjugated system that facilitated the separative efficiency of photogenerated electron-hole pairs and intensified the utilization of visible light. This study provided a new means to design and fabricate highly efficient and environmentally friendly non-metallic photocatalytic materials.


Assuntos
Grafite , Nanosferas , Compostos de Nitrogênio , Rodaminas , Triazinas , Poluentes Químicos da Água , Nanosferas/química , Catálise , Triazinas/química , Grafite/química , Rodaminas/química , Compostos de Nitrogênio/química , Poluentes Químicos da Água/química , Luz , Tetraciclina/química , Nitrilas/química , Processos Fotoquímicos , Fotólise
2.
Anal Chim Acta ; 1313: 342700, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38862203

RESUMO

BACKGROUND: L-p-Boronophehylalanine (BPA) is used in boron neutron capture therapy (BNCT), which is a novel selective cancer radiotherapy technique. It is important to measure BPA levels in human blood for effective radiotherapy; a prompt gamma-ray spectrometer, ICP-AES, and ICP-MS have been used for this purpose. However, these methods require sophisticated and expensive apparatuses as well as experienced analysts. Herein, we propose an HPLC-FL method for the determination of BPA after precolumn derivatization. A new fluorogenic reagent for aryl boronic acid derivatives, namely, 4-iodobenzonitrile, was employed for the fluorogenic derivatization of BPA based on the Suzuki coupling reaction. RESULTS: After the fluorogenic derivatization, a fluorescent cyanobiphenyl derivative is formed with maximum fluorescence at 335 nm after excitation at 290 nm. The developed method showed good linearity (r2=0.997) over the concentration range of 0.5-1000 nmol/L, and the detection limit (S/N = 3) was 0.26 nmol/L. The proposed method is more sensitive than previously reported methods for the determination of BPA, including the ICP-MS. Finally, the proposed method was successively applied to the measurement of BPA in human whole blood samples with a good recovery rate (≥95.7 %) using only 10 µL of blood sample. The proposed method offers a simple and efficient solution for monitoring BPA levels in BNCT-treated patients. SIGNIFICANCE: 4-Iodobenzonitrile was investigated as a new fluorogenic reagent for BPA based on Suzuki coupling. A new HPLC-FL method for BPA in whole blood samples with ultrasensitivity was developed. The developed method is superior in sensitivity to all previously reported methods for BPA. The method requires only a very small sample volume, making it suitable for micro-blood analysis of BPA via fingerstick sampling.


Assuntos
Corantes Fluorescentes , Nitrilas , Fenilalanina , Humanos , Nitrilas/química , Nitrilas/sangue , Cromatografia Líquida de Alta Pressão/métodos , Corantes Fluorescentes/química , Fenilalanina/sangue , Fenilalanina/análogos & derivados , Fenilalanina/química , Espectrometria de Fluorescência/métodos , Limite de Detecção , Compostos de Boro/química , Compostos de Boro/sangue
3.
Se Pu ; 42(6): 564-571, 2024 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-38845517

RESUMO

Protein phosphorylation plays an important role in cellular signaling and disease development. Advances in mass spectrometry-based proteomics have enabled qualitative and quantitative phosphorylation studies as well as in-depth biological explorations for biomarker discovery and signaling pathway analysis. However, the dynamic changes that occur during phosphorylation and the low abundance of target analytes render direct analysis difficult because mass spectral detection offers no selectivity, unlike immunoassays such as Western blot and enzyme-linked immunosorbent assay (ELISA). The present study aimed to solve one of the key problems in the specific and efficient isolation of phosphorylated peptides. A method based on a magnetic carbon nitride composite coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was developed for the enrichment and analysis of phosphopeptides with low abundance in complex samples. Magnetic carbon nitride composite was synthesized and characterized by electron microscopy, infrared spectroscopy, and X-ray diffractometry. The composite showed a well-distributed two-dimensional layered structure and functional groups with excellent paramagnetic performance. Two classical phosphoproteins, namely, α- and ß-caseins, were selected as model phosphorylated samples to assess the performance of the proposed enrichment technique. The magnetic carbon nitride composite exhibited high selectivity and sensitivity for phosphopeptide enrichment. The limit of detection was determined by MALDI-TOF-MS analysis to be 0.1 fmol. The selectivity of the method was investigated using the digest mixtures of α-casein, ß-casein, and bovine serum albumin (BSA) with different mass ratios (1∶1∶1000, 1∶1∶2000, and 1∶1∶5000). Direct analysis of the samples revealed the dominance of spectral signals from the abundant peptides in BSA. After enrichment with the magnetic carbon nitride composite, the high concentration of background proteins was washed away and only the signals of the phosphopeptides were captured. The signals from the casein proteins were clearly observed with little background noise, indicating the high selectivity of the composite material. The robustness of the method was tested by assessing the reusability of the same batch of magnetic carbon nitride materials over 20 cycles of enrichment. The composite showed nearly the same enrichment ability even after several cycles of reuse, demonstrating its potential applicability for a large number of clinical samples. Finally, the method was applied to the analysis of phosphopeptides from several commonly used phosphoprotein-containing samples, including skimmed milk digest, human serum, and human saliva; these samples are significant in the analysis of food quality, disease biomarkers, and liquid biopsies for cancer. Without enrichment, no phosphopeptide was detected because of the high abundance of nonphosphopeptide materials dominating the spectral signals obtained. After pretreatment with the developed magnetic carbon nitride composite, most of the phosphosites were identified with high selectivity and sensitivity via MALDI-TOF-MS. These results revealed the practicality of the developed approach for clinical applications. In addition, our method may potentially be employed for phosphoproteomics with real complex biological samples.


Assuntos
Nitrilas , Fosfopeptídeos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fosfopeptídeos/análise , Fosfopeptídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Nitrilas/química , Caseínas/química , Caseínas/análise , Fosforilação , Proteômica/métodos , Magnetismo
4.
Bioorg Chem ; 149: 107485, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38824700

RESUMO

There is a continuous and pressing need to establish new brain-penetrant bioactive compounds with anti-cancer properties. To this end, a new series of 4'-((4-substituted-4,5-dihydro-1H-1,2,3-triazol-1-yl)methyl)-[1,1'-biphenyl]-2-carbonitrile (OTBN-1,2,3-triazole) derivatives were synthesized by click chemistry. The series of bioactive compounds were designed and synthesized from diverse alkynes and N3-OTBN, using copper (II) acetate monohydrate in aqueous dimethylformamide at room temperature. Besides being highly cost-effective and significantly reducing synthesis, the reaction yielded 91-98 % of the target products without the need of any additional steps or chromatographic techniques. Two analogues exhibit promising anti-cancer biological activities. Analogue 4l shows highly specific cytostatic activity against lung cancer cells, while analogue 4k exhibits pan-cancer anti-growth activity. A kinase screen suggests compound 4k has single-digit micromolar activity against kinase STK33. High STK33 RNA expression correlates strongly with poorer patient outcomes in both adult and pediatric glioma. Compound 4k potently inhibits cell proliferation, invasion, and 3D neurosphere formation in primary patient-derived glioma cell lines. The observed anti-cancer activity is enhanced in combination with specific clinically relevant small molecule inhibitors. Herein we establish a novel biochemical kinase inhibitory function for click-chemistry-derived OTBN-1,2,3-triazole analogues and further report their anti-cancer activity in vitro for the first time.


Assuntos
Antineoplásicos , Proliferação de Células , Química Click , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores de Proteínas Quinases , Proteínas Serina-Treonina Quinases , Triazóis , Humanos , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Estrutura-Atividade , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Estrutura Molecular , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Linhagem Celular Tumoral , Nitrilas/química , Nitrilas/farmacologia , Nitrilas/síntese química
5.
Mikrochim Acta ; 191(7): 411, 2024 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900245

RESUMO

Ratiometric fluorescence and colorimetric strategies for detecting activity of butyrylcholinesterase (BChE) in human serum were developed by using g-C3N4 nanosheets, silver ion (Ag+) and o-phenylenediamine (OPD) as chromogenic agents. The oxidation-reduction reaction of OPD and Ag+ generates 2,3-diaminophenazine (oxOPD). Under exciation at 370 nm, g-C3N4 nanosheets and oxOPD emit fluorescence at 440 nm (F440) and 560 nm (F560), respectively. Additionally, oxOPD exhibits quenching ability towards g-C3N4 nanosheets via photoinduced electron transfer (PET) process. Thiocholine (TCh), as a product of BChE-catalyzed hydrolysis reaction of butylthiocholine iodide (BTCh), can coordinate with Ag+ intensively, and consequently diminish the amount of free Ag+ in the testing system. Less amount of free Ag+ leads to less production of oxOPD, resulting in less fluorescence quenching towards g-C3N4 nanosheets as well as less fluorescence emission of oxOPD. Therefore, by using g-C3N4 nanosheets and oxOPD as fluorescence indicators, the intensity ratio of their fluorescence (F440/F560) was calculated and employed to evaluate the activity of BChE. Similarly, the color variation of oxOPD indicated by the absorbance at 420 nm (ΔA420) was monitored for the same purpose. These strategies were validated to be sensitive and selective for detecting BChE activity in human serum, with limits of detection (LODs) of 0.1 U L-1 for ratiometric fluorescence mode and 0.7 U L-1 for colorimetric mode.


Assuntos
Butirilcolinesterase , Colorimetria , Nanoestruturas , Fenilenodiaminas , Prata , Espectrometria de Fluorescência , Humanos , Colorimetria/métodos , Prata/química , Fenilenodiaminas/química , Butirilcolinesterase/sangue , Butirilcolinesterase/química , Espectrometria de Fluorescência/métodos , Nanoestruturas/química , Compostos de Nitrogênio/química , Limite de Detecção , Nitrilas/química , Grafite , Fenazinas
6.
Environ Pollut ; 354: 124183, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38772513

RESUMO

Soil organic matter (SOM) significantly impacts the detection accuracy of Cd2+ and Pb2+ using square wave anodic stripping voltammetry (SWASV) due to the complexation of SOM to heavy metal ions (HMIs), thereby attenuating SWASV signals. This study explored an effective pretreatment method that combined low-pressure ultraviolet (LPUV) photolysis with the ZnO/g-C3N4 photocatalyst, activating the photocatalyst to generate highly oxidative •OH radicals and O2•- radicals, which effectively disrupted this complexation, consequently restoring the electroactivity of HMIs and achieving high-fidelity SWASV signals. The parameters of the LPUV-ZnO/g-C3N4 photocatalytic system were meticulously optimized, including the pH of photolysis, duration of photolysis, g-C3N4 mass fraction, and concentration of the photocatalyst. Furthermore, the ZnO/g-C3N4 photocatalyst was thoroughly characterized, with an in-depth investigation on the synergistic interaction between ZnO and g-C3N4 and the mechanisms contributing to the restoration of SWASV signals. This synergistic interaction effectively separated charge carriers and reduced charge transfer resistance, enabling photogenerated electrons (e-) from the conduction band of g-C3N4 to be quickly transferred to the conduction band of ZnO, preventing the recombination of e- and hole (h+) and generating more radicals to disrupt complexation and restore the SWASV signals. Finally, the analysis of HMIs in real soil extracts using the proposed pretreatment method demonstrated high detection accuracy of 94.9% for Cd2+ and 99.8% for Pb2+, which validated the feasibility and effectiveness of the proposed method in environmental applications.


Assuntos
Cádmio , Chumbo , Poluentes do Solo , Solo , Raios Ultravioleta , Óxido de Zinco , Óxido de Zinco/química , Poluentes do Solo/análise , Solo/química , Catálise , Técnicas Eletroquímicas/métodos , Fotólise , Nitrilas/química , Grafite/química , Compostos de Nitrogênio
7.
Rapid Commun Mass Spectrom ; 38(15): e9770, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38773864

RESUMO

RATIONALE: Chlorothalonil (CHT), a broad-spectrum fungicide, has been employed widely to control foliar diseases, whereas with a major metabolite of polar 4-hydroxychlorothalonil (CHT-4-OH), only an acceptable nonpolar CHT residue is allowed by most countries. This study involves the method development for CHT residue in vegetables/fruits using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with a novel modified discharge-adaptor (DA) interface. METHODS: CHT residue was analyzed using LC-MS/MS with DA interface (LC-DA-MS/MS), developed in our previous works. A DA was placed on the electrospray tip to switch the ionization modes. A modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method was applied to extract CHT residue of vegetables/fruits efficiently with less sample preparation time and analysis cost. RESULTS: CHT and CHT-4-OH spiked in four different vegetables/fruits were extracted using the modified QuEChERS method. After LC with isocratic elution, CHT and CHT-4-OH were separated within 3 min. Using LC-DA-MS/MS, the ion signals of CHT were improved two to three times, and the limit of quantification of 5 ng/g and linearity (r2 > 0.99) in the range of 5-200 ng/g were achieved using 10 g of vegetables/fruits. The precision and accuracy were within 15% each. The modified QuEChERS and LC-DA-MS/MS were applied to examine eight field-grown vegetables/fruits; 9.5 and 2588.9 ng/g of CHT were detected in two vegetables/fruits. CONCLUSION: LC-DA-MS/MS combined with modified QuEChERS was successfully applied to determine CHT residue <10 ng/g in vegetables/fruits and with satisfied validation results. The developed method could reduce both analysis cost and time, attributing to simplifications in modified QuEChERS, isocratic elution, and DA interface in LC-DA-MS/MS.


Assuntos
Frutas , Fungicidas Industriais , Nitrilas , Resíduos de Praguicidas , Espectrometria de Massas em Tandem , Verduras , Espectrometria de Massas em Tandem/métodos , Verduras/química , Nitrilas/análise , Nitrilas/química , Cromatografia Líquida/métodos , Resíduos de Praguicidas/análise , Frutas/química , Fungicidas Industriais/análise , Limite de Detecção , Reprodutibilidade dos Testes , Contaminação de Alimentos/análise
8.
Sci Total Environ ; 935: 173195, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38750752

RESUMO

The distribution fate of chlorothalonil (CHT) in the environment (soil and water) and fruits is controlled by the capacity of cuticles to adsorb and desorb CHT, which directly affects the safety of both the environment and fruits. Batch experiments were conducted to reveal the adsorption-desorption behaviors of CHT in the cuticles of apple and red jujube. The adsorption kinetics showed that both physisorption and chemisorption occurred during the adsorption process. Furthermore, the isothermal adsorption of CHT in the fruit cuticles followed the Freundlich model. The thermodynamic parameters (ΔG ≤ -26.16 kJ/mol, ΔH ≥ 31.05 kJ/mol, ΔS ≥ 0.20 kJ/(mol K) showed that the whole CHT adsorption process was spontaneous, and the hydrophobic interaction was predominant. The CHT adsorption capacity of the apple cuticle was higher than that of the red jujube cuticle, potentially due to the significantly higher alkanes content of apples than that of red jujubes. An appropriate ionic strength (0.01 moL/L) could induce a higher adsorption capacity. In addition, the desorption kinetics were shown to conform to a Quasi-first-order model, meaning that not all the adsorbed CHT could be easily desorbed. The desorption ratios in apple and red jujube cuticles were 41.38% and 35.64%, respectively. The results of Fourier-transformed infrared spectroscopy and X-ray photoelectron spectroscopy further confirmed that CHT could be adsorbed and retained in the fruit cuticles. Investigating the adsorption-desorption behavior of CHT in the apple and red jujube cuticles allowed to determine the ratio of its final distribution in the fruits and environment, providing a theoretical basis to evaluate the risk of residue pesticide.


Assuntos
Frutas , Malus , Nitrilas , Ziziphus , Adsorção , Ziziphus/química , Malus/química , Nitrilas/química , Frutas/química , Cinética , Fungicidas Industriais/química
9.
J Biomol Struct Dyn ; 42(10): 5053-5071, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38764131

RESUMO

The synthesis of two new hexahydroisoquinoline-4-carbonitrile derivatives (3a and 3b) is reported along with spectroscopic data and their crystal structures. In compound 3a, the intramolecular O-H···O hydrogen bond constraints the acetyl and hydroxyl groups to be syn. In the crystal, inversion dimers are generated by C-H···O hydrogen bonds and are connected into layers parallel to (10-1) by additional C-H···O hydrogen bonds. The layers are stacked with Cl···S contacts 0.17 Å less than the sum of the respective van der Waals radii. The conformation of the compound 3b is partially determined by the intramolecular O-H···O hydrogen bond. A puckering analysis of the tetrahydroisoquinoline unit was performed. In the crystal, O-H···O and C-H···O hydrogen bonds together with C-H···π(ring) interactions form layers parallel to (01-1) which pack with normal van der Waals interactions. To understand the binding efficiency and stability of the title molecules, molecular docking, and 100 ns dynamic simulation analyses were performed with CDK5A1. To rationalize their structure-activity relationship(s), a DFT study at the B3LYP/6-311++G** theoretical level was also done. The 3D Hirshfled surfaces were also taken to investigate the crystal packings of both compounds. In addition, their ADMET properties were explored.Communicated by Ramaswamy H. Sarma.


Assuntos
Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Cristalografia por Raios X , Quinases Ciclina-Dependentes/antagonistas & inibidores , Quinases Ciclina-Dependentes/química , Quinases Ciclina-Dependentes/metabolismo , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/farmacologia , Conformação Molecular , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Modelos Moleculares , Nitrilas/química , Simulação de Dinâmica Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Humanos
10.
J Mass Spectrom ; 59(6): e5043, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38789127

RESUMO

The assignment of structure by tandem mass spectrometry (MS/MS) relies on the interpretation of the fragmentation behavior of gas-phase ions. Mass spectra were acquired for a series of heterocyclic mimetics of acidic amino acids and a related series of nitrile amino acids. All amino acids were readily protonated or deprotonated by electrospray ionization (ESI), and distinctive fragmentation processes were observed when the ions were subjected to collision-induced dissociation (CID). The deprotonated heterocycles showed bond cleavages of the 3-hydroxyfurazan ring with formation of oxoisocyanate and the complementary deprotonated nitrile amino acid. Further fragmentation of the deprotonated nitrile amino acids was greatly dependent on the length of the alkyl nitrile side chain. Competing losses of CO2 versus HCN occurred from α-cyanoglycinate (shortest chain), whereas water was lost from 2-amino-5-cyanopentanoate (longest chain). Interestingly, loss of acrylonitrile by a McLafferty-type fragmentation process was detected for 2-amino-4-cyanobutanoate, and several competing processes were observed for ß-cyanoalanate. In one process, cyanide ion was formed either by consecutive losses of ammonia, carbon dioxide, and acetylene or by a one-step decarboxylative elimination. In another, complementary ions were obtained from ß-cyanoalanate by loss of acetonitrile or HN=CHCO2H. Fragmentation of the protonated 3-hydroxyfurazan and nitrile amino acids resulted in the cumulative loss (H2O + CO), a loss that is commonly observed for protonated aliphatic α-amino acids. Overall, the distinct fragmentation behavior of the multifunctional 3-hydroxyfurazan amino acids correlated with the charged site, whereas fragmentations of the deprotonated nitrile amino acids showed cooperative interactions between the nitrile and the carboxylate groups.


Assuntos
Aminoácidos , Nitrilas , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Nitrilas/química , Aminoácidos/química , Aminoácidos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Íons/química
11.
Bioorg Chem ; 148: 107433, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38754311

RESUMO

Second-generation AR antagonists, such as enzalutamide, are the primary therapeutic agents for advanced prostate cancer. However, the development of both primary and secondary drug resistance leads to treatment failures and patient mortality. Bifunctional agents that simultaneously antagonize and degrade AR block the AR signaling pathway more completely and exhibit excellent antiproliferative activity against wild-type and drug-resistant prostate cancer cells. Here, we reported the discovery and optimization of a series of biphenyl derivatives as androgen receptor antagonists and degraders. These biphenyl derivatives exhibited potent antiproliferative activity against LNCaP and 22Rv1 cells. Our discoveries enrich the diversity of small molecule AR degraders and offer insights for the development of novel AR degraders for the treatment of enzalutamide-resistant prostate cancer.


Assuntos
Antagonistas de Receptores de Andrógenos , Antineoplásicos , Benzamidas , Compostos de Bifenilo , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Nitrilas , Feniltioidantoína , Neoplasias da Próstata , Receptores Androgênicos , Humanos , Masculino , Benzamidas/farmacologia , Benzamidas/química , Benzamidas/síntese química , Nitrilas/química , Nitrilas/farmacologia , Feniltioidantoína/farmacologia , Feniltioidantoína/análogos & derivados , Feniltioidantoína/química , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Receptores Androgênicos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Relação Estrutura-Atividade , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Estrutura Molecular , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/química , Antagonistas de Receptores de Andrógenos/síntese química , Antagonistas de Receptores de Andrógenos/uso terapêutico , Descoberta de Drogas , Ensaios de Seleção de Medicamentos Antitumorais , Relação Dose-Resposta a Droga , Linhagem Celular Tumoral
12.
Environ Res ; 252(Pt 4): 119121, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38734291

RESUMO

Extensive utilization of pesticides and herbicides to boost agricultural production increased the environmental health risks, which can be mitigate with the aid of highly sensitive detection systems. In this study, an electrochemical sensor for monitoring the carcinogenic pesticides in the environmental samples has been developed based on sulfur-doped graphitic-carbon nitride-gold nanoparticles (SCN-AuNPs) nanohybrid. Thermal polycondensation of melamine with thiourea followed by solvent exfoliation via ultrasonication leads to SCN formation and electroless deposition of AuNPs on SCN leads to SCN-AuNPs nanohybrid synthesis. The chemical composition, S-doping, and the morphology of the nanohybrid were confirmed by various microscopic and spectroscopic tools. The as-synthesized nanohybrid was fabricated with glassy carbon (GC) electrode for determining the carcinogenic hydrazine (HZ) and atrazine (ATZ) in field water samples. The present sensor exhibited superior electrocatalytic activity than GC/SCN and GC/AuNPs electrodes due to the synergism between SCN and AuNPs and the amperometric studies showed the good linear range of detection of 20 nM-0.5 mM and 500 nM-0.5 mM with the limit of detection of 0.22 and 69 nM (S/N = 3) and excellent sensitivity of 1173.5 and 13.96 µA mM-1 cm-2 towards HZ and ATZ, respectively. Ultimately, the present sensor is exploited in environmental samples for monitoring HZ and ATZ and the obtained results are validated with high-performance liquid chromatography (HPLC) technique. The excellent recovery percentage and close agreement with the results of HPLC analysis proved the practicability of the present sensor. In addition, the as-prepared materials were utilized for the photocatalytic degradation of ATZ and the SCN-AuNPs nanohybrid exhibited higher photocatalytic activity with the removal efficiency of 93.6% at 90 min. Finally, the degradation mechanism was investigated and discussed.


Assuntos
Carcinógenos , Ouro , Grafite , Nanopartículas Metálicas , Poluentes Químicos da Água , Ouro/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Nanopartículas Metálicas/química , Grafite/química , Carcinógenos/análise , Atrazina/análise , Atrazina/química , Enxofre/química , Enxofre/análise , Técnicas Eletroquímicas/métodos , Hidrazinas/análise , Hidrazinas/química , Compostos de Nitrogênio/química , Compostos de Nitrogênio/análise , Nitrilas/química , Nitrilas/análise , Monitoramento Ambiental/métodos
13.
Biosens Bioelectron ; 259: 116415, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38795497

RESUMO

The on-site detection of pyrethroids, particularly type II pyrethroids, remains a challenging task in complex vegetable samples. Herein, a novel method based on naphthalimide was developed to realize the specific detection of type II pyrethroids by hydrolyzing and utilizing the compound m-phenoxybenzaldehyde (3-PBD). Hydrazine group, used as the appropriate moiety, was introduced into the fluorescent dye 1,8-naphthalimide to construct the fluoroprobe NAP. In the presence of 3-PBD, NAP displayed the prominently enhanced fluorescence and also exhibited high selectivity. This proposed method exhibited high anti-inference effects in complex media, realizing sensitive detection of 3-PBD with linear range of 2.15-800 µM and a low detection limit (LOD) of 0.64 µM. The underlying fluorescence-responsive mechanisms were in-depth elucidated by combining spectral analyses with TD-DFT theoretical calculations. Additionally, a direct and rapid hydrolysis method for deltamethrin in celery was established, achieving a high hydrolysis efficiency of >90% within 15 min. Furthermore, a portable fluorescence sensor (PFS) was developed based on high-power LEDs and photodetectors. PFS supplied a LOD of 2.23 µM for 3-PBD and exhibited comparable stability by a fluorescence spectrometer when detecting celery hydrolysate. Moreover, external power source is not required for PFS operations, thereby enabling rapid and on-site detection by transmitting data to a smartphone via bluetooth. These findings extend the academic knowledge in the field of specific pyrethroids detection and contribute to the development of on-site methods for pesticide residual analyses in food matrices.


Assuntos
Técnicas Biossensoriais , Corantes Fluorescentes , Limite de Detecção , Naftalimidas , Piretrinas , Espectrometria de Fluorescência , Piretrinas/análise , Naftalimidas/química , Técnicas Biossensoriais/instrumentação , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , Contaminação de Alimentos/análise , Nitrilas/química , Inseticidas/análise
14.
Anal Chem ; 96(19): 7772-7779, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38698542

RESUMO

There is growing attention focused toward the problems of ecological sustainability and food safety raised from the abuse of herbicides, which underscores the need for the development of a portable and reliable sensor for simple, rapid, and user-friendly on-site analysis of herbicide residues. Herein, a novel multifunctional hydrogel composite is explored to serve as a portable and flexible sensor for the facile and efficient analysis of atrazine (ATZ) residues. The hydrogel electrode is fabricated by doping graphite-phase carbon nitride (g-C3N4) into the aramid nanofiber reinforced poly(vinyl alcohol) hydrogel via a simple solution-casting procedure. Benefiting from the excellent electroactivity and large specific surface area of the solid nanoscale component, the prepared hydrogel sensor is capable of simple, rapid, and sensitive detection of ATZ with a detection limit down to 0.002 ng/mL and per test time less than 1 min. After combination with a smartphone-controlled portable electrochemical analyzer, the flexible sensor exhibited satisfactory analytical performance for the ATZ assay. We further demonstrated the applications of the sensor in the evaluation of the ATZ residues in real water and soil samples as well as the user-friendly on-site point-of-need detection of ATZ residues on various agricultural products. We envision that this flexible and portable sensor will open a new avenue on the development of next-generation analytical tools for herbicide monitoring in the environment and agricultural products.


Assuntos
Atrazina , Técnicas Eletroquímicas , Herbicidas , Hidrogéis , Atrazina/análise , Herbicidas/análise , Hidrogéis/química , Técnicas Eletroquímicas/instrumentação , Grafite/química , Eletrodos , Limite de Detecção , Nitrilas/química , Nitrilas/análise , Nanofibras/química , Poluentes Químicos da Água/análise
15.
Int J Mol Sci ; 25(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38732166

RESUMO

This current study assessed the impacts of morphology adjustment of perovskite BiFeO3 (BFO) on the construction and photocatalytic activity of P-infused g-C3N4/U-BiFeO3 (U-BFO/PCN) heterostructured composite photocatalysts. Favorable formation of U-BFO/PCN composites was attained via urea-aided morphology-controlled hydrothermal synthesis of BFO followed by solvosonication-mediated fusion with already synthesized P-g-C3N4 to form U-BFO/PCN composites. The prepared bare and composite photocatalysts' morphological, textural, structural, optical, and photocatalytic performance were meticulously examined through various analytical characterization techniques and photodegradation of aqueous rhodamine B (RhB). Ellipsoids and flakes morphological structures were obtained for U-BFO and BFO, and their effects on the successful fabrication of the heterojunctions were also established. The U-BFO/PCN composite exhibits 99.2% efficiency within 20 min of visible-light irradiation, surpassing BFO/PCN (88.5%), PCN (66.8%), and U-BFO (26.1%). The pseudo-first-order kinetics of U-BFO/PCN composites is 2.41 × 10-1 min-1, equivalent to 2.2 times, 57 times, and 4.3 times of BFO/PCN (1.08 × 10-1 min-1), U-BFO, (4.20 × 10-3 min-1), and PCN, (5.60 × 10-2 min-1), respectively. The recyclability test demonstrates an outstanding photostability for U-BFO/PCN after four cyclic runs. This improved photocatalytic activity exhibited by the composites can be attributed to enhanced visible-light utilization and additional accessible active sites due to surface and electronic band modification of CN via P-doping and effective charge separation achieved via successful composites formation.


Assuntos
Bismuto , Fotólise , Rodaminas , Catálise , Bismuto/química , Rodaminas/química , Luz , Compostos Férricos/química , Compostos de Nitrogênio/química , Titânio/química , Processos Fotoquímicos , Nitrilas/química , Cinética , Grafite , Óxidos , Compostos de Cálcio
16.
Food Chem ; 453: 139652, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38761737

RESUMO

Diclazuril (DIC) is a broad-spectrum anti-coccidiosis drug of the triazine class, widely used in poultry farming. The overuse of DIC may lead to its accumulation in animal bodies, which may enter the food chain and threaten human health. In this work, we fabricated a stable Eu3+-doped UiO-66 fluorescence sensor (EuUHIPA-30) for the sensitive detection of DIC. Among 20 veterinary drugs, the fluorescence of EuUHIPA-30 selectively responds to DIC, with a low detection limit (0.19 µM) and fast response (10 s). EuUHIPA-30 is recyclable and can detect DIC in chicken and eggs with good recoveries. Moreover, a smartphone-integrated paper-based sensor enables the instrument-free, rapid, visual, and intelligent detection of DIC in chickens and eggs. This work provides a promising candidate for practical fluorescent DIC sensing in animal-derived food to promote food safety.


Assuntos
Galinhas , Ovos , Európio , Contaminação de Alimentos , Estruturas Metalorgânicas , Nitrilas , Triazinas , Triazinas/análise , Animais , Ovos/análise , Nitrilas/química , Nitrilas/análise , Contaminação de Alimentos/análise , Estruturas Metalorgânicas/química , Európio/química , Limite de Detecção , Espectrometria de Fluorescência/métodos , Coccidiostáticos/análise
17.
J Am Chem Soc ; 146(19): 13317-13325, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38700457

RESUMO

We describe the synthesis and biological testing of ruthenium-bipyridine ruxolitinib (RuBiRuxo), a photoreleasable form of ruxolitinib, a JAK inhibitor used as an antitumoral agent in cutaneous T-cell lymphomas (CTCL). This novel caged compound is synthesized efficiently, is stable in aqueous solution at room temperature, and is photoreleased rapidly by visible light. Irradiation of RuBiRuxo reduces cell proliferation and induces apoptosis in a light- and time-dependent manner in a CTCL cell line. This effect is specific and is mediated by a decreased phosphorylation of STAT proteins. Our results demonstrate the potential of ruthenium-based photocompounds and light-based therapeutic approaches for the potential treatment of cutaneous lymphomas and other pathologies.


Assuntos
Antineoplásicos , Apoptose , Proliferação de Células , Nitrilas , Pirazóis , Pirimidinas , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Nitrilas/química , Nitrilas/farmacologia , Nitrilas/síntese química , Pirimidinas/química , Pirimidinas/farmacologia , Pirimidinas/síntese química , Apoptose/efeitos dos fármacos , Pirazóis/farmacologia , Pirazóis/química , Pirazóis/síntese química , Linhagem Celular Tumoral , Inibidores de Janus Quinases/farmacologia , Inibidores de Janus Quinases/química , Inibidores de Janus Quinases/síntese química , Rutênio/química , Rutênio/farmacologia , Luz , Estrutura Molecular , Janus Quinases/antagonistas & inibidores , Janus Quinases/metabolismo
18.
Int J Biol Macromol ; 270(Pt 1): 132096, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38710245

RESUMO

A simple technique was developed for the modification of cotton materials that is inexpensive, environmentally friendly, and very effective. Waste Cotton fabrics (WCFs) are loaded with propolis extract (PE) for Cu2+ removal. Then, Cu2+ underwent a pyrolysis process with modified cuttlebone (CB) at 900 °C for 5 h. The surface of the prepared materials was characterized using X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray (SEM-EDX), Fourier transform infrared (FTIR), BET, particle sizes, thermogravimetric analysis (TGA) and zeta potential analysis. The Cu2+ metal ions from an aqueous solution were removed using WCFs/PE, and DLM was subsequently removed using pyro WCFs/PE/Cu/CB. The as-prepared NPs exhibited the face-centered cubic structure of WCFs/PE/Cu/CB with crystallite sizes ranging from 386.70 to 653.10 nm. FTIR spectra revealed that CB was present on the surface of the resulting WCFs/PE/Cu. SEM revealed the dispersion of a uniformly flower-like morphology over a large area. Sorption studies were performed based on parameters that included pH, dose, contact time, and initial concentration. The adsorption isotherm and the kinetic studies of the DLM adsorption process were applied at a pH of 5.0 and a temperature of 25 °C using several isotherms and kinetic models. The results revealed qmax (20.51 mg/g) with R2 = 0.97, the Langmuir isotherm that best matches the experimental data. Hence, the Langmuir isotherm suggests that it is the model that best describes sorption on homogenous surfaces or surface-supporting sites with various affinities. The correlation coefficient R2, χ2, adjusted correlation coefficient, and error functions like root mean square (RMSE), normalized root mean square error (NRMES), and mean absolute error (MAE) were used to evaluate the best-fit models to the experimental adsorption data. Moreover, cost estimation for the prepared adsorbent WCFs/PE/Cu showed that it costs approximately 3 USD/g, which is a cheap adsorbent compared to other similar adsorbents reported in the literature. The examined WCFs/PE have significant applicability potential for Cu2+-laden wastewater treatment due to their superior Cu2+ metal ions adsorption capability and reusability. The cytotoxicity and safety study showed that at higher concentrations, it resulted in much less cell viability. Additionally, the removal efficiency of Cu2+ metal ions from synthetic, realistic industrial wastewater using WCFs/PE reached up to 96.29 %, demonstrating good adsorption capability. Thus, there is a huge possibility of accomplishing this and performing well. This study paves the way for the reuse and valorization of selected adsorbents following circular economy principles. Two green metrics were applied, the Analytical Eco-scale and the Analytical GREEnness Calculator (AGREE).


Assuntos
Cobre , Fibra de Algodão , Nanocompostos , Nitrilas , Piretrinas , Pirólise , Poluentes Químicos da Água , Cobre/química , Nanocompostos/química , Adsorção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Nitrilas/química , Piretrinas/química , Piretrinas/isolamento & purificação , Purificação da Água/métodos , Cinética , Concentração de Íons de Hidrogênio , Própole/química
19.
Chemosphere ; 359: 142286, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38729439

RESUMO

Antibiotics are emerging organic pollutants that have attracted huge attention owing to their abundant use and associated ecological threats. The aim of this study is to develop and use photocatalysts to degrade antibiotics, including tetracycline (TC), ciprofloxacin (CIP), and amoxicillin (AMOX). Therefore, a novel Z-scheme heterojunction composite of g-C3N4 (gCN) and 3D flower-like Bi2WO6 (BW) perovskite structure was designed and developed, namely Bi2WO6/g-C3N4 (BW/gCN), which can degrade low-concentration of antibiotics in aquatic environments under visible light. According to the Density Functional Theory (DFT) calculation and the characterization results of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FITR), Scanning electron microscopy - energy spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS), this heterojunction was formed in the recombination process. Furthermore, the results of 15 wt%-BW/gCN photocatalytic experiments showed that the photodegradation rates (Rp) of TC, CIP, and AMOX were 92.4%, 90.1% and 82.3%, respectively, with good stability in three-cycle photocatalytic experiments. Finally, the quenching experiment of free radicals showed that the holes (h+) and superoxide radicals (·O2-) play a more important role than the hydroxyl radicals (·OH) in photocatalysis. In addition, a possible antibiotic degradation pathway was hypothesized on the basis of High performance liquid chromatography (HPLC) analysis. In general, we have developed an effective catalyst for photocatalytic degradation of antibiotic pollutants and analyzed its photocatalytic degradation mechanism, which provides new ideas for follow-up research and expands its application in the field of antibiotic composite pollution prevention and control.


Assuntos
Antibacterianos , Bismuto , Compostos de Cálcio , Óxidos , Fotólise , Titânio , Antibacterianos/química , Óxidos/química , Titânio/química , Catálise , Bismuto/química , Compostos de Cálcio/química , Poluentes Químicos da Água/química , Grafite/química , Tetraciclina/química , Amoxicilina/química , Ciprofloxacina/química , Luz , Compostos de Nitrogênio/química , Nitrilas/química
20.
Chemosphere ; 358: 142158, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38697561

RESUMO

A novel dual Photo-Fenton photocatalyst Fe2O3-Fe-CN with excellent Fe(III)/Fe(II) conversion efficiency and trace metal ion leaching rate has been fabricated by in-situ deposition of α-Fe2O3 quantum dots on ultrathin porous Fe-doped carbon nitride (Fe-CN) nanosheets. The iron species in Fe-CN and α-Fe2O3 QDs constitute a mutually reinforcing dual Photo-Fenton effect. The 4% Fe2O3-Fe-CN showed superior performance with kobs values 8.60 and 4.80 folders greater than pure CN and Fe-CN, respectively. The synergistic effect between α-Fe2O3 QDs and the ultrathin porous structure of Fe-CN is the primary reason for the outstanding catalytic performance exhibited by α-Fe2O3/Fe-CN. On one hand, the ultrathin porous structure of Fe-CN promotes the rapid transfer of photogenerated electrons. On the other hand, the efficient photogenerated charge separation at the α-Fe2O3/Fe-CN interface enables more photogenerated electrons to participate in the Fe3+/Fe2+ conversion and H2O2 activation. The trapping experiments demonstrate that •OH and •O2- are the primary active species in TC degradation. This work presents novel insights into the design of efficient heterogeneous Fenton catalysts for practical applications.


Assuntos
Compostos Férricos , Peróxido de Hidrogênio , Ferro , Pontos Quânticos , Catálise , Compostos Férricos/química , Ferro/química , Peróxido de Hidrogênio/química , Pontos Quânticos/química , Processos Fotoquímicos , Nitrilas/química , Porosidade , Grafite , Compostos de Nitrogênio
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