Category Archives: ChemistryOpen

Direct Detection of Viral Infections from Swab Samples by Probe‐Gated Silica Nanoparticle‐Based Lateral Flow Assay

Posted on 12 October 2023 by

Here, universal-modifiable probe-gated silica nanoparticles (SNPs) based lateral flow assay (LFA) is developed in the interest of the rapid and early detection of viral infections. The most superior advantage of the rapid assay is its utility in detecting various sides of the virus directly from the human swab samples and its adaptability to detect various types of viruses. The NSP12, NSP9, and E gene targets of CoV-2 were used as detection targets.

Abstract

Point-of-care diagnosis is crucial to control the spreading of viral infections. Here, universal-modifiable probe-gated silica nanoparticles (SNPs) based lateral flow assay (LFA) is developed in the interest of the rapid and early detection of viral infections. The most superior advantage of the rapid assay is its utility in detecting various sides of the virus directly from the human swab samples and its adaptability to detect various types of viruses. For this purpose, a high concentration of fluorescein and rhodamine B as a reporting material was loaded into SNPs with excellent loading capacity and measured using standard curve, 4.19 μmol ⋅ g⁻¹ and 1.23 μmol ⋅ g⁻¹, respectively. As a model organism, severe acute respiratory syndrome coronavirus-2 (CoV-2) infections were selected by targeting its nonstructural (NSP9, NSP12) and envelope (E) genes as target sites of the virus. We showed that NSP12-gated SNPs-based LFA significantly outperformed detection of viral infection in 15 minutes from 0.73 pg ⋅ mL⁻¹ synthetic viral solution and with a dilution of 1 : 10³ of unprocessed human samples with an increasing test line intensity compared to steady state (n=12). Compared to the RT-qPCR method, the sensitivity, specificity, and accuracy of NSP12-gated SNPs were calculated as 100 %, 83 %, and 92 %, respectively. Finally, this modifiable nanoparticle system is a high-performance sensing technique that could take advantage of upcoming point-of-care testing markets for viral infection detections.

Selective Fluorescent Sensing for Iron in Aqueous Solution by A Novel Functionalized Pillar[5]arene

Posted on 6 October 2023 by

An anthracene-appended water-soluble pillar[5]arene was prepared to construct a supramolecular fluorescent sensor system to accurately and selectively detect Fe³⁺ in water.

Abstract

Iron ion is one of the most physiologically important elements in metabolic processes, indispensable for all living systems. Since its excess can lead to severe diseases, new approaches for its monitoring in water samples are urgently needed to meet requirements. Here, we firstly report a novel and universal route for the synthesis of a series of pillar[n]arene derivates containing one benzoquinone unit by photocatalysis. With this in hand, an anthracene – appended water – soluble pillar[5]arene (H) with excellent fluorescence sensing potency was prepared. H enabled the ultrasensitive detection of iron ions in aqueous solution with limits of detection of 10⁻⁸ M. Over a wide range of metal ions, H exhibited specific selectivity toward Fe³⁺. More importantly, H could still properly operate in a simulated sewage sample, coexisting with multiple interference ions.

A Theobromine Derivative with Anticancer Properties Targeting VEGFR‐2: Semisynthesis, in silico and in vitro Studies

Posted on 6 October 2023 by

A new theobromine derivative, (T-1-AFPB), was designed as a VEGFR-2 inhibitor. DFT calculations indicated T-1-AFPB’s stability and reactivity. T-1-AFPB’s potential binding and inhibition of VEGFR-2 were indicated by molecular docking, MD simulations, PLIP, MM-GBSA, and PCA studies. T-1-AFPB’s drug likeness was indicated several in silico ADMET investigations. Subsequently, T-1-AFPB was semi-synthesized, and in vitro assays confirmed its potential to inhibit VEGFR-2 and to inhibit the growth of HepG2 and MCF-7 cancer cell lines, displaying very high selectivity indices and inducing apoptosis.

Abstract

A computer-assisted drug design (CADD) approach was utilized to design a new acetamido-N-(para-fluorophenyl)benzamide) derivative of the naturally occurring alkaloid, theobromine, (T-1-APFPB), following the pharmacophoric features of VEGFR-2 inhibitors. The stability and reactivity of T-1-AFPB were assessed through density functional theory (DFT) calculations. Molecular docking assessments showed T-1-AFPB’s potential to bind with and inhibit VEGFR-2. The precise binding of T-1-AFPB against VEGFR-2 with optimal energy was further confirmed through several molecular dynamics (MD) simulations, PLIP, MM-GBSA, and PCA studies. Then, T-1-AFPB (4-(2-(3,7-Dimethyl-2,6-dioxo-2,3,6,7-tetrahydro-1H-purin-1-yl)acetamido)-N-(4-fluorophenyl)benzamide) was semi-synthesized and the in vitro assays showed its potential to inhibit VEGFR-2 with an IC₅₀ value of 69 nM (sorafenib's IC₅₀ was 56 nM) and to inhibit the growth of HepG2 and MCF-7 cancer cell lines with IC₅₀ values of 2.24±0.02 and 3.26±0.02 μM, respectively. Moreover, T-1-AFPB displayed very high selectivity indices against normal Vero cell lines. Furthermore, T-1-AFPB induced early (from 0.72 to 19.12) and late (from 0.13 to 6.37) apoptosis in HepG2 cell lines. In conclusion, the combined computational and experimental approaches demonstrated the efficacy and safety of T-1-APFPB providing it as a promising lead VEGFR-2 inhibitor for further development aiming at cancer therapy.

Exploring the Effects of Various Capping Agents on Zinc Sulfide Quantum Dot Characteristics and In‐vitro Fate

Posted on 6 October 2023 by

The effects of three different commonly employed capping agents; mercaptoethanol (ME), mercaptoacetic acid (MAA), and cysteamine (CA), on the physicochemical and optical characteristics of ZnS QDs, as well as their interactions with cells, were studied. These capping agents were found to have considerable effects on the behavior and properties of ZnS QDs such as stability, cytotoxicity and aggregation. Consequently, it is advisable to select capping agents in accordance with the specific objectives of the research.

Abstract

The choice of capping agents used during the synthesis process of quantum dots (QDs) can significantly influence their fate and fundamental properties. Hence, choosing an appropriate capping agent is a critical step in both synthesis and biomedical application of QDs. In this research, ZnS QDs were synthesized via chemical precipitation process and three commonly employed capping agents, namely mercaptoethanol (ME), mercaptoacetic acid (MAA), and cysteamine (CA), were used to stabilize the QDs. This study was aimed to examine how these capping agents impact the physicochemical and optical characteristics of ZnS QDs, as well as their interactions with biological systems. The findings revealed that the capping agents had considerable effects on the behavior and properties of ZnS QDs. MAA-QD exhibited superior crystal lattice, smaller size, and significant quantum yield (QY). In contrast, CA-QDs demonstrated the lowest QY and the highest tendency for aggregation. ME-QDs exhibited intermediate characteristics, along with an acceptable level of cytotoxicity, rapid uptake by cells, and efficient escape from lysosomes. Consequently, it is advisable to select capping agents in accordance with the specific objectives of the research.

Characteristics of the Frustrated Lewis Pairs (FLPs) on the Surface of Albite and the Corresponding Mechanism of H2 Activation

Posted on 6 October 2023 by nYannan Zhou, nXuegang Luon

In the reaction of H₂ activation, the interaction between the HOMO of H₂ and the SOMO of LB and the electron acceptance characteristics of LA are the key factors. The activation energy of H₂ is the required activation energy from the ground state to the excited state, once the excited state is produced, dissociation adsorption of H₂ will occur directly.

Abstract

The characteristics of frustrated Lewis pairs (FLPs) on albite surfaces were analyzed with density functional theory, and the reaction mechanism for H₂ activation by the FLPs was studied. The results show that albite is an ideal substrate material with FLPs, and its (001) and (010) surfaces have the typical characteristics of FLPs. In the case of H₂ activation, the interaction between the HOMO of H₂ and the SOMO of the Lewis base and the electron acceptance characteristics of the Lewis acid are the key factors. In fact, the activation energy of H₂ is the required activation energy from the ground state to the excited state, and once the excited state is produced, the dissociative adsorption of H₂ will occur directly. This study provides a new ideas and a reference for research on the construction of novel solid FLPs catalysts using ultramicro channel materials.

Cover Feature: (ChemistryOpen 10/2023)

Posted on 3 October 2023 by Wiley: ChemistryOpen: Table of Contents

Synthesis and Characterization of Ultra‐Small Gold Nanoparticles in the Ionic Liquid 1‐Ethyl‐3‐methylimidazolium Dicyanamide, [Emim][DCA]

Posted on 31 August 2023 by nJana Hildebrandt, nAndreas Taubert, nAndreas F. Thünemannn

Formation of 1 nm-sized gold clusters with long-stability in an ionic liquid is reported. Formation via a three-stage process is suggested. Cluster growth from gold nuclei takes place according to the Lifshitz–Slyozov–Wagner (LSW) model followed by oriented attachment to form colloidal stable clusters.

Abstract

We report on gold clusters with around 62 gold atoms and a diameter of 1.15±0.10 nm. Dispersions of the clusters are long-term stable for two years at ambient conditions. The synthesis was performed by mixing tetrachloroauric acid (HAuCl₄ ⋅ 3 H₂O) with the ionic liquid 1-ethyl-3-methylimidazolium dicyanamide ([Emim][DCA]) at temperatures of 20 to 80 °C. Characterization was performed with small-angle X-ray scattering (SAXS), UV-Vis spectroscopy, and MALDI-TOF mass spectrometry. A three-stage model is proposed for the formation of the clusters, in which cluster growth from gold nuclei takes place according to the Lifshitz-Slyozov-Wagner (LSW) model followed by oriented attachment to form colloidal stable clusters.

Antiproliferative Activities and SwissADME Predictions of Physicochemical Properties of Carbonyl Group‐Modified Rotenone Analogues

Posted on 17 August 2023 by

Rotenone derivatives were synthesized through modifications of the carbonyl group and their antiproliferative activities were evaluated against various cancer cell lines (MCF-7, A549, and HCT116). The physicochemical properties and drug-likeness of the derivatives were evaluated using the SwissADME webtool.

Abstract

Rotenone is a naturally occurring compound shown to exhibit antiproliferative activity against various cancer cell lines, indicating its potential as a lead anticancer agent. However, its toxicity against normal cells has prompted further investigation and chemical modifications. In this study, a library of carbonyl group-modified rotenone derivatives was synthesized and evaluated for their antiproliferative activities against MCF-7 breast cancer cells, A549 human lung carcinoma cells, and HCT116 human colorectal cancer cells using 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. The results showed several promising compounds that inhibited cell proliferation. Specifically, the oxime and alcohol rotenone derivatives exhibited antiproliferative activities against all 3 cancer cell lines, while the ethoxy, carbamate, and alkene derivatives are selective against MCF-7 (IC₅₀=5.72 μM), HCT116 (IC₅₀=8.86 μM), and A549 (IC₅₀=0.11 μM), respectively. SwissADME analysis showed that the physicochemical properties and drug-likeness of the synthesized rotenone derivatives were within the set limits, suggesting the favorable characteristics of these compounds for drug development. The findings obtained in this work highlight the potential of rotenone derivatives as promising chemotherapeutic candidates.

Lithium‐Ion Battery Cathode Recycling through a Closed‐Loop Process Using a Choline Chloride‐Ethylene Glycol‐Based Deep‐Eutectic Solvent in the Presence of Acid

Posted on 26 July 2023 by nDelphine Yetim, nLenka Svecova, nJean‐Claude Leprêtren

A novel closed-loop method for Li and Co recovery from a lithium cobalt oxide (LCO) material using a deep eutectic solvent (DES) based on choline chloride (ChCl) and ethylene glycol (EG) with an additional source of protons. This process allowed to quantitatively recover Co and Li, highlighting the importance of adding a precise amount of protons to drive Co dissolution. In addition, the DES was used in three successive leaching/recovery cycles without any degradation.

Abstract

This study evaluates the ability of a choline chloride:ethylene glycol-based deep eutectic solvent (DES) to dissolve lithium cobalt oxide (LCO) which is used as a cathode active material in Li-ion batteries. Both a commercial powder and spent cathodes have been used. It was demonstrated that if HCl is added in a small proportion, a rapid and efficient LCO dissolution can be achieved. Indeed, if more than three protons are added per one cobalt atom present in the LCO structure, a complete dissolution of the material is accomplished within 2 h at 80 °C. This result might be considered as a viable alternative compared to the literature where much longer reaction times and higher temperatures are applied to achieve similar results with the same DES system used either pure or in presence of additional reducing agents. It was further demonstrated that Co and Li can be fully precipitated after Li₂CO₃ addition. This precipitation does neither pollute the DES nor leads to its degradation provided the pH does not exceed 10. Finally, it was shown that two additional reuse cycles can be carried out without any decrease of recovery efficiency, while no degradation products have been detected within the DES phase.

Predicting GPR40 Agonists with A Deep Learning‐Based Ensemble Model

Posted on 5 July 2023 by

Various GPR40 agonists and non-agonists for model training and evaluation were collection and used for building and systematically optimizing an ensemble model for predicting GPR40 agonists. The ensemble model was built based on 20 baseline models, which were consisting of different algorithms and molecular representations. And the ensemble model showed greater performance than the performance of any baseline model.

Abstract

Recent studies have identified G protein-coupled receptor 40 (GPR40) as a promising target for treating type 2 diabetes mellitus, and GPR40 agonists have several superior effects over other hypoglycemic drugs, including cardiovascular protection and suppression of glucagon levels. In this study, we constructed an up-to-date GPR40 ligand dataset for training models and performed a systematic optimization of the ensemble model, resulting in a powerful ensemble model (ROC AUC: 0.9496) for distinguishing GPR40 agonists and non-agonists. The ensemble model is divided into three layers, and the optimization process is carried out in each layer. We believe that these results will prove helpful for both the development of GPR40 agonists and ensemble models. All the data and models are available on GitHub. (https://github.com/Jiamin-Yang/ensemble_model)