Search Results (94)

In this work, we investigate the effect of ligand chemistry on the optical and electrical properties of copper indium disulphide (CuInS₂) quantum dots (QDs) and evaluate their suitability for photodetection with simple device structures. CuInS₂ QDs capped with dodecanethiol (DDT) ligands were synthesized, followed by processes to exchange the DDT with thioglycolic acid (TGA), mercaptopropionic acid (MPA), or thioacetamide (TAA) ligands. Photoluminescence (PL) and UV-Visible absorption studies revealed that while TGA- and MPA-capped QDs retained strong emission, TAA-capped QDs exhibited significant quenching, indicating surface defect formation due to poor ligand binding. Metal–semiconductor–metal (MSM) test structures were fabricated using the QD films as the active layer to study their electrical properties under dark and UV-illuminated conditions. Devices based on MPA- and TGA-capped QD films demonstrated currents that were 7–9 times higher than those of devices with native DDT ligands, with significantly enhanced photocurrent-to-dark current ratios of 2.6 and 1.7, respectively, highlighting the effective charge transport pathways enabled by the shorter ligands. The device with TGA-capped QD film also responded well to 20 kHz pulsed UV excitation, underscoring the strong potential of this simple MSM structure for photodetection and optical switching applications. Full article

Background: Clostridium perfringens is an infectious agent of concern in wild/farmed shellfish. Hence, this study assessed shellfish-borne Clostridium perfringens (ShbCp) prevalence. Methods: A total of 1469 ShbCp from 2336 shellfish were modelled using hierarchical generalized linear and 1000-permutation-based-mixed-effects, meta-regression models. Results: The overall ShbCp prevalence was 54.12% (19.73–84.99) with a 32.02% (14.52–56.64) toxigenic rate and a higher estimate in 2020–2025 (41.01%, 17.00–70.23) versus 1970–2019 (20.01%, 4.49–57.08). Culture media significantly affect ShbCp recovery, with cooked meat medium and thioglycollate medium registering higher estimates (77% and 25.15%, respectively) than selective agars (<7%). The molluscans had a higher ShbCp rate (60.68%) than crustaceans (1.57%) and cephalopods (0.14%); oysters (85.97%) than mussels (71.81%), clams (50.38%), slug/snails (48.23%), scallops (16.24%), crabs (11.91%), shrimps (1.05%), and squids (0.42%); and Crassostrea gigas (89.27%) versus Ruditapes philippinarum (45.92%) versus Mytilus galloprovincialis (30.14%). ShbCp differed significantly by nations but not by continent with Spain (87.79%) having the highest rate, then China (47.01%), Japan (43.91%), the USA (10.44%), and Greece (0.00%); South America (51.36%), then Asia (44.77%), Europe (21.97%), and North America (10.44%). Sample size, growth medium, nation, and shellfish class significantly explained 27.58%, 72.30%, 67.52%, and 28.51% ($R^2$) variance in ShbCp prevalence, respectively. Conclusions: The present study estimated a high ShbCp prevalence, suggesting a significant public health risk. It recommends that C. perfringens should be incorporated as a supplemental indicator into shellfish safety/shellfish water quality monitoring alongside traditional indicators. Also, geographical data gaps from Africa, Latin America, the Middle East, and Oceania underline the need for national and global monitoring attention and priority on C. perfringens in shellfish/shellfish beds. Full article

Antibiotics are increasingly detected in aquatic environments, raising environmental and public health concerns due to their persistence and contribution to antimicrobial resistance. This study examines copper sulfide (CuS) nanostructures as potential materials for sustainable water remediation. CuS nanoparticles were synthesized in aqueous media using thioglycolic acid (TGA) as a stabilizing ligand and characterized by UV–Vis, FTIR, XRD, TEM, SEM, and EDS. An optimized Cu:TGA molar ratio of 1:6 yielded stable nanoparticles with a distinct excitonic absorption at 312 nm, strong ligand coordination, and a covellite-type hexagonal crystalline phase. These nanoparticles were subsequently immobilized within calcium–alginate hydrogel beads of two controlled size regimes, producing structurally uniform and recoverable composites. SEM imaging revealed qualitative increases in surface texturing following CuS incorporation, while bead diameter analyses indicated minimal changes in morphology. Overall, the results confirm the successful synthesis, stabilization, and immobilization of CuS nanoparticles within alginate beads and establish a robust materials platform with potential for future adsorption and photocatalytic applications targeting antibiotic contaminants in water. Full article

We report the first synthesis of 3,5-diamino-substituted dithieno[3,2-b:2′,3′-d]thiophene derivatives, bearing alkoxycarbonyl or acetyl groups at C-2 and C-6 positions. The target compounds were prepared via the reaction of 3,4-dibromothiophene-2,5-dicarbonitrile with alkyl thioglycolates or mercaptoacetone in the presence of DBU and isolated in 67–87% yield. The key dinitrile was synthesized in 76% yield from 3,4-dibromothiophene-2,5-dicarbaldehyde. In turn, this dialdehyde was prepared on a multigram scale from commercially available 2,5-dimethylthiophene in three steps. The resulting dithieno[3,2-b:2′,3′-d]thiophenes serve as valuable building blocks for materials chemistry, offering multiple reactive sites for further structural elaboration and property tuning. Full article

Dysregulated macrophage polarization is associated with various diseases, including sepsis, atherosclerosis, and fibrotic diseases. While taurine is known to exert immunomodulatory effects, its mechanism in regulating M1 macrophage polarization and interleukin-1β (IL-1β) production remains incompletely understood. This study aimed to elucidate the role of taurine in modulating macrophage immunometabolism and inflammatory signaling. Using thioglycolate-elicited peritoneal macrophages and macrophage cell lines, we assessed taurine’s impact on lipopolysaccharide (LPS)/interferon-γ (IFN-γ)-induced M1 polarization through metabolomics and a range of molecular biology techniques. Pharmacological manipulation of the JAK1/2-STAT1 pathway and an LPS-induced murine sepsis model were used for mechanistic and therapeutic validation. Our results demonstrate that taurine significantly suppressed M1 polarization. Metabolomic profiling uniquely identified a marked increase in intracellular spermine as a key metabolic alteration induced by taurine. This increased spermine subsequently inhibited JAK1/2-STAT1 activation, leading to reduced IL-1β release. In mice, taurine alleviated systemic inflammation, reduced pathological damage in multiple organs, and decreased intestinal M1 macrophage infiltration. These findings establish a novel mechanism where taurine attenuates M1 polarization and IL-1β production through metabolically driven spermine accumulation and subsequent JAK1/2-STAT1 suppression, highlighting its therapeutic potential for inflammatory diseases. Full article

Molybdenite and chalcopyrite closely coexist and have good natural floatability. During the Cu-Mo separation process, it is necessary to enhance the inhibition of chalcopyrite to reduce its influence on molybdenite. In this paper, a combined inhibitor, sodium thioglycollate (HSCH₂COONa) and sodium sulfide (Na₂S), with a molar ratio of 2:1, was obtained through pure mineral flotation experiments. It could reduce the impact on molybdenite while maintaining a good inhibitory effect on chalcopyrite. In the artificial mixed minerals test, the use of the combined inhibitor (80 mg/L) can achieve good indicators with Mo grade and recovery rate of 54.34% and 88.12%, respectively, and Cu grade of 2.15%. The contact angle test shows that the combined inhibitor can significantly reduce the wettability of the chalcopyrite surface while having a relatively small effect on molybdenite. The infrared spectroscopy and SEM-EDS energy spectrum indicated that the combined inhibitor C = O and S-H groups underwent chemical reactions on the surface of chalcopyrite and squeezed out kerosene on the surface of chalcopyrite. Molecular dynamics simulations indicate that the HS⁻, S²⁻, and HSCH₂COO⁻ components in the combined inhibitor are more likely to act on the surface of chalcopyrite, exerting an enhanced inhibitory effect on chalcopyrite. Full article

The efficient separation of chalcopyrite from molybdenite is crucial for the utilization of copper–molybdenum ores and is inevitably influenced by the presence of metal ions in the pulp. However, the underlying impact mechanisms remain unclear. This study systematically investigated the influence of Cu²⁺ on the flotation separation of chalcopyrite and molybdenite, with sodium thioglycolate (STG) as a depressant. Flotation experiments revealed that Cu²⁺ in the STG system significantly reduced molybdenite recovery and hindered selective separation. Characterization using contact angle, zeta potential, and UV–Vis analysis demonstrated that the presence of Cu²⁺ triggered STG adsorption on the molybdenite surface, thereby increasing its hydrophilicity. XPS analysis showed that Cu²⁺ adsorbed onto the molybdenite surface as Cu(I), creating reactive sites for the –SH or –COO⁻ groups in STG. This interaction forms a stable molybdenite–Cu(I)–STG complex through chemisorption, significantly suppressing molybdenite flotation. DFT calculations further demonstrated that Cu²⁺ enhanced the reactivity between STG and molybdenite. These findings provide a comprehensive understanding of the influences of Cu²⁺ on the flotation separation between chalcopyrite from molybdenite, providing valuable insights into further optimizing copper–molybdenum flotation separation processes. Full article

Water pollution by antibiotics and heavy metals threatens the ecological environment and human health globally, yet there is no rapid method to detect multiple antibiotics and metal ions simultaneously. A simple, fast, and ultra-sensitive colorimetric chemosensor for the simultaneous detection of moxifloxacin (MOX), ciprofloxacin (CIP), and Cr(III) based on the aggregation of ammonium thioglycolate (ATG)-functionalized gold nanoparticles (ATG-AuNPs) was developed. Following the addition of MOX, CIP, and Cr(III), a color change in the solution was observed from wine-red to blue-grey. The UV–Vis signal of the ATG-AuNPs system blended with MOX, CIP, and Cr(III) in the range of 0~200 µM, 0~100 µM, and 0~5 µM was assessed and measured with detection limits (LODs) of 1.57 µM, 1.30 µM, and 57.1 nM calculated by 3σ/S, respectively. Therefore, this system has the potential to act as an effective colorimetric chemosensor for simultaneously detecting MOX, CIP, and Cr(III) in complex environmental systems. Full article

Hair straighteners are among the most technically complex products to be safely and effectively developed, and this challenge has increased even more with the higher incidence of resistant hair among consumers. This underscores the importance of studying new active ingredients, combinations and carrier formulations to improve performance without compromising safety. In this research, we compared eight hair-straightening formulations with different active ingredients and/or concentrations to develop new, safer and more effective texture modifiers. Eight formulations were developed and compared with each other and to controls (virgin and bleached hair) regarding mechanical and thermal resistance, cuticle morphology, hair shine and fiber diameter. Results showed that all formulations were safe and effective at straightening hair. Specifically, 13.3% and 9.4% ammonium thioglycolate (G03 and G04) were more suitable for wavy and curly hair, 12.5% and 7.9% amino methyl propanol thioglycolate (G05 and G06) for finer or chemically processed hair, 5% and 4% sodium cysteamine (G07 and G08) for curly and tight curly hair to control volume, and 2% and 1% of a combination of ammonium thioglycolate with sodium thioglycolate (G09 and G10) for more resistant wavy and curly hair. Full article

Semiconductor colloidal nanostructures capped with chiral organic molecules are a research hotspot due to their wide range of important implications for photonic and spintronic applications. However, to date, the study of chiral ligands has been limited almost exclusively to naturally occurring chiral amino and hydroxy acids, which typically contain only one stereocenter. Here, we show the pronounced induction of chirality in atomically thin CdSe nanoplatelets (NPLs) by capping them with enantiopure menthol derivatives as multi-stereocenter molecules. L-(−)/D-(+)-menthyl thioglycolate, easily synthesized from L-(−)/D-(+)-menthol, is attached to Cd-rich (001) basal planes of 2- and 3-monolayer (ML) CdSe NPLs. We show the appearance of narrow sign-alternating bands in the circular dichroism (CD) spectra of 2 ML NPLs corresponding to heavy-hole (HH) and light-hole (LH) excitons with maximal dissymmetry g-factor up to 2.5 × 10⁻⁴. The most intense CD bands correspond to the lower-energy HH exciton, and in comparison with the N-acetyl-L-Cysteine ligand, the CD bands for L-(−)-menthyl thioglycolate have the opposite sign. The CD measurements are complemented with magnetic CD measurements and first-principles modeling. The obtained results may be of interest for designing new chiral semiconductor nanostructures and improving understanding of their chiroptical properties. Full article

Due to the possible coexistence of Klebsiella pneumoniae (KP) and Candida albicans (CA), strains of KP and CA with biofilm production properties clinically isolated from patients were tested. The production of biofilms from the combined organisms (KP+CA) was higher than the biofilms from each organism alone, as indicated by crystal violet and z-stack immunofluorescence. In parallel, the bacterial abundance in KP + CA was similar to KP, but the fungal abundance was higher than CA (culture method), implying that CA grows better in the presence of KP. Proteomic analysis was performed to compare KP + CA biofilm to KP biofilm alone. With isolated mouse neutrophils (thioglycolate induction), KP + CA biofilms induced less prominent responses than KP biofilms, as determined by (i) neutrophilic supernatant cytokines (ELISA) and (ii) neutrophil extracellular traps (NETs), using immunofluorescent images (neutrophil elastase, myeloperoxidase, and citrullinated histone 3), peptidyl arginine deiminase 4 (PAD4) expression, and cell-free DNA. Likewise, intratracheal KP + CA in C57BL/6 mice induces less severe pneumonia than KP alone, as indicated by organ injury (serum creatinine and alanine transaminase) (colorimetric assays), cytokines (ELISA), bronchoalveolar lavage fluid parameters (bacterial culture and neutrophil abundances using a hemocytometer), histology score (H&E stains), and NETs (immunofluorescence on the lung tissue). In conclusion, the biofilm biomass of KP + CA was mostly produced from CA with less potent neutrophil activation and less severe pneumonia than KP alone. Hence, fungi in the respiratory tract might benefit the host in some situations, despite the well-known adverse effects of fungi. Full article

To obtain versatile nanoplatforms comparable for various bio-applications, synthesis and functionalization of two inorganic nanoparticles (NPs), i.e., gold (AuNPs) and iron oxide (SPIONs), are described for different NP diameters. Chosen ligands have adapted chemical function to graft to the surfaces of the NPs (thiols and phosphonates, respectively) and the identical frequently used external carboxyl group for comparison of the NPs’ material effect on their final behavior. To further evaluate molecular length effect, AuNPs are functionalized by different ligands. Numerous characterizations highlight the colloidal stability when grafting organic molecules on NPs. The potentiality of the functionalized NPs to react efficiently with a protein monolayer is finally evaluated by grafting them on a protein covered chip, characterized by atomic force microscopy. Comparison of the NPs’ surface densities and measured heights enable observation of different NPs’ reactivity and infer the influence of the inorganic core material, as well as the NPs’ size and ligand length. AuNPs have higher affinities to biomolecules, especially when covered by shorter ligands. NP ligands should be chosen not only based on their length but also on their chemical chain, which affects proteic layer interactions. This original multiplex comparison method using AFM is of great interest to screen the effects of used NP materials and functionalization when developing theranostic nanoplatforms. Full article

In this study, we developed an efficient strategy for constructing thieno[3,2-b]thiophene molecules from 3-nitrothiophenes, containing carbonyl fragments at the C-2 and C-5 atoms, by nucleophilic aromatic substitution of the nitro group in these substrates. It was shown that the reaction of 3-nitrothiophene-2,5-dicarboxylates with thiophenols, thioglycolates and 2-mercaptoacetone in the presence of K₂CO₃ proceeds rapidly via nucleophilic displacement of the nitro group with the formation of 3-sulfenylthiophene-2,5-dicarboxylates. Further treatment of the resulting thiophene-2,5-dicarboxylates, which have -SCH₂CO₂Alk or -SCH₂COMe moiety at C-3 atom, with sodium alcoholates afford obtaining 2,3,5-trisubstituted thieno[3,2-b]thiophene derivatives according to the Dieckman condensation. In turn, the reaction of methyl 5-formyl-4-nitrothiophene-2-carboxylate with methyl thioglycolate or 2-mercaptoacetone in the presence of K₂CO₃ proceeds to directly form 2,5-disubstituted thieno[3,2-b]thiophenes. Full article

In order to reduce chronic hair flyaways/frizz, both reducing and oxidizing agents have to be used, leaving aside the hair damage issues. This study presents changes in hair morphology caused by treatment with a shampoo containing only reducing agents, excluding oxidizing agents that affect critical hair damages. As a result of flyaway/frizz improvement rates calculated through monitoring of the area of light transmittance in the hair tresses, reducing agents, such as ammonium thioglycolate (ATG), L-cysteine, and sodium sulfite were found to be effective in decreasing hair flyaway/frizz. Additionally, the methods to maintain homeostasis and control damage caused by oxidation during washing were also used to see flyaway/frizz improvement rates. Measurements using electrostatic force microscopy (EFM) showed that the surface charge of hair tresses treated with shampoo containing reducing agents was lowered. Using Raman spectroscopic analysis, it has been suggested that these treatments with reducing agents induced a 3D structural transition of the hair from an α-helix to a random coil. In addition, this structural release was confirmed, identifying the reduction in the enthalpy of the α-helix using differential scanning calorimetry (DSC). Furthermore, we verified that this change causes no hair damage through a tensile strength test. Therefore, the formulation of shampoo with reducing agents can be used as an effective strategy to care for hair flyaway/frizz without hair damage issues. Full article

Background and Objectives: This study aims to identify types of bacterial species in women visiting obstetrics/gynecology centers in Riyadh City, Saudi Arabia, during different pregnancy trimesters. Materials and Methods: This cross-sectional study was conducted among pregnant and nonpregnant women seeking care at Alyamamah Hospital, obstetrics/gynecology center, Riyadh, Saudi Arabia. A total of 110 [pregnant = 90 and nonpregnant = 20] individuals were recruited based on inclusion/exclusion criteria. Personal data, plaque index (PI), and gingival index (GI) were recorded. Bacterial samples were collected using sterile absorbent paper points from the gingival sulcus of pregnant females during the first, second, and third trimesters and compared to a control group of nonpregnant females. Thioglycolate broth containing the absorbent paper points was incubated at 37 °C for 24–48 h. After growth, the microorganisms were subjected to a Gram stain. The VITEK 2 system and conventional methods were used to identify various types of bacterial species from the gingival sulcus of pregnant and nonpregnant women. Chi-square tests and nonparametric tests were applied to the data. Results: The bacterial characterization indicated that Actinomyces naeslundii (AN) was the most predominant bacteria found in the study participants, followed by Lactobacillus fermentum (LF) (23.6%), Veillonella (VL) (10%), and unidentified organisms (9.1%). When the presence of subgingival bacterial species was compared between pregnant and nonpregnant women, a statistically significant difference was observed (p < 0.001). LF was the predominant bacteria in 9 nonpregnant women (45%) and 8 pregnant women in the first pregnancy trimester (44.4%). However, during the second (17 women: 48.6%) and third pregnancy (17 women: 45.9%) trimesters, AN becomes the predominant bacteria. A statistically significant difference was observed when the prevalence of various bacterial species was compared across the three pregnancy trimesters (p = 0.010). The plaque and gingival scores of pregnant and nonpregnant women showed no significant difference. Conclusions: In different trimesters of pregnancy, pregnant women’s gingival crevices showed significant microbial changes without affecting gingival inflammation. Full article