Thiourea Research Articles

Dual-mode fluorescent and colorimetric sensing of thiourea and aluminum ion in natural water based on CuO nanoparticles.

CuO nanoparticles with good water solubility and uniform particle size were successfully prepared. Interestingly, the oxidase-like activity of CuO NPs was continuously enhanced by the addition of thiourea (TU), and the enzyme activity was further enhanced by the addition of aluminum ion (Al3+). By systematically exploring and optimizing the experimental conditions, including the key parameters such as temperature, reaction time, and pH, a fluorescence-colorimetric dual-mode sensing system based on CuO nanoparticles was constructed. The detection range of TU and Al3+ were 1-100 µM and 1-100 µM, respectively, and the selectivity and precision of detection were further improved. In addition, the catalytic mechanism of CuO NPs as oxidase-like catalysts and the specific process in the reaction were investigated. Finally, the nano-sensing system was successfully applied to the analysis of three real environmental samples, namely, tap water, lake water and river water, which provided an effective new strategy for the future development of nano-sensing technology for TU and Al3+.

Targeted Defect Repair and Multi-functional Interface Construction for the Direct Regeneration of Spent LiFePO4 Cathodes.

Due to the low economic benefits and environmental pollution of traditional recycling methods, the disposal of spent LiFePO4 (SLFP) presents a significant challenge. The capacity fade of SLFP cathode is primarily caused by lithium loss and formation of a Fe (III) phase. Herein, a synergistic repair effect is proposed to achieve defect repair and multi-functional interface construction for the direct regeneration of SLFP. Tannic acid (TA) forms a compact coating precursor for a carbon layer on SLFP with abundant functional groups and creates a mildly acidic environment to enhance the reducibility of thiourea (TU). Therefore, TU reduces Fe (III) to Fe (II) and repairs Li-Fe anti-site defects of SLFP, while at the same time acting as a source of N/S-doping elements for the carbon layer at a lower temperature (140°C). The multi-functional carbon layer improves the properties of the regenerated LiFePO4 (RLFP) due to the enhanced conductivity, structure maintenance and protection, and the improved kinetics of Li+ transport. Furthermore, the Fe─O and P─O bonds are strengthened, further enhancing the structural stability of the RLFP. Consequently, the RLFP demonstrates outstanding performance with a discharge capacity of 141.3 mAh g-1 and capacity retention of 72% after 1000 cycles at 1C.

High loading and sustained-release system of doxorubicin-carbon dots as nanocarriers for cancer therapeutics

Nanocarriers for drugs have been investigated for decades, yet it is still challenging to achieve sustained release from nanomaterials due to drug loading inefficiency and burst release. In this study, we developed novel functional carbon dots (CDs) and investigated the therapeutic efficacy by studying the loading efficiency and release behavior of the anticancer drug doxorubicin (DOX). CDs were successfully synthesized using a one-step pyrolysis method with varying concentrations of citric acid (CA) and thiourea (TU). Functional groups, morphology, particle size, and zeta potential of synthesized CT-CDs and DOX loaded CT-CDs were investigated by UV-visible, Fluorescence, dynamic light scattering, Zeta Potential measurements, FTIR, and transmission electron microscopy. The zeta potential data revealed DOX loading onto CT-CDs by charge difference, i.e. -24.6 ± 0.44 mV (CT-CDs) and 20.57 ± 0.55 mV (DOX-CT-CDs). DOX was loaded on CDs with a loading efficiency of 88.67 ± 0.36%.In vitrodrug release studies confirmed pH-dependent biphasic drug release, with an initial burst effect and sustained release of DOX was found to be 21.42 ± 0.28% (pH 5), 13.30 ± 0.03% (pH 7.4), and 13.95 ± 0.18% (pH 9) even after 144 h at 37 °C. The CT-CDs were non-toxic and biocompatible with L929 Fibroblasts cells. The cytotoxic effect of DOX-CT-CDs showed a concentration-dependent effect after 48 h with Glioblastoma U251 cells. Flow cytometry was used to examine the cellular uptake of CT-CDs and DOX-CT-CDs in L929 and U251 cells. It was observed that the maximum CT-CDs uptake was around 75% at the end of 24 h. This study showed that the synthesized fluorescent CT-CDs demonstrated a high drug loading capacity, pH-dependent sustained release of DOX, and high cellular uptake by mammalian cells. We believe this work provides practical and biocompatible CDs for chemotherapeutic drug delivery that can be applied to other drugs for certain therapeutic aims.

Optimizing Energy Solutions: Mott-Schottky Engineered 1D/3D CoWO4(OH)2·H2O/MoS2 Heterostructure for Advanced Energy Storage and Conversion Application.

Heterostructure engineering offers a powerful approach to creating innovative electrocatalysts. By combining different materials, it can achieve synergistic effects that enhance both charge storage and electrocatalytic activity. In this work, it is capitalized on this concept by designing a 1D/3D CoWO4(OH)2·H2O/molybdenum disulfide (CTH/MoS2) heterostructure. It is achieved this by in situ depositing 3D MoS2 nanoflowers on 1D CTH nanorods. To explore the impact of precursor choice, various sulfur (S) sources is investigated. Interestingly, the S precursor influenced the dimensionality of the MoS2 component. For example, L-cysteine (L-cys), and glutathione (GSH) resulted in 0D morphologies, thiourea (TU) led to a 2D structure, and thioacetamide (TAA) yielded a desirable 3D architecture. Notably, the 1D/3D CTH/MoS2-TAA heterostructure exhibited exceptional performance in both supercapacitors (SCs) and quantum dot-sensitized solar cells (QDSSCs). This achievement can be attributed to several factors: the synergetic effect between 1D CTH and 3D MoS2, improved accessibility due to the multi-dimensional structure, and a tailored electronic structure facilitated by the Mott-Schottky (M-S) interaction arising from the different material Fermi levels. This interaction further enhances conductivity, ultimately leading to the observed high specific capacity in SCs (154.44mAhg-1 at 3mAcm-2) and remarkable photovoltaic efficiency in QDSSCs (6.48%).

Thiourea and arginine synergistically preserve redox homeostasis and ionic balance for alleviating salinity stress in wheat

Plant growth regulators are cost-effective and efficient methods for enhancing plant defenses under stress conditions. This study investigates the ability of two plant growth-regulating substances, thiourea (TU) and arginine (Arg), to mitigate salinity stress in wheat. The results show that both TU and Arg, particularly when used together, modify plant growth under salinity stress. Their application significantly increases the activities of antioxidant enzymes while decreasing the levels of reactive oxygen species (ROS), malondialdehyde (MDA), and relative electrolyte leakage (REL) in wheat seedlings. Additionally, these treatments significantly reduce the concentrations of Na+ and Ca2+ and the Na+/K+ ratio, while significantly increasing K+ levels, thereby preserving ionic osmotic balance. Importantly, TU and Arg markedly enhance the chlorophyll content, net photosynthetic rate, and gas exchange rate in wheat seedlings under salinity stress. The use of TU and Arg, either individually or in combination, results in a 9.03–47.45% increase in dry matter accumulation, with the maximum increase observed when both are used together. Overall, this study highlights that maintaining redox homeostasis and ionic balance are crucial for enhancing plant tolerance to salinity stress. Furthermore, TU and Arg are recommended as potential plant growth regulators to boost wheat productivity under such conditions, especially when applied together.

Thiourea enhanced oxidase-like activity of CeO2/CuxO nanozyme for fluorescence/colorimetric detection of thiourea and glutathione

A novel fluorescence/colorimetric dual-mode sensor, based on enhancement of the oxidase-like activity of CeO2/CuxO nanozyme towards the oxidation of o-phenylenediamine (OPD) induced by thiourea (TU), has been proposed for TU detection. The catalytic activity enhancement on CeO2/CuxO can be attributed to the strong electron-donation ability of TU, which promoted hydroxyl radical generation and amplified OPD oxidization with enhanced dual-signal readout. By integrating a portable paper-chip and smartphone system, this CeO2/CuxO-OPD system achieved on-site visual colorimetric analysis of TU. The dual-mode sensor demonstrated high sensitivity and specificity in recognizing TU, with a detection limit (LOD) of 1.90 μM and a linear range (LR) 2.5–80 μM in fluorescent mode; as well as an LOD of 6.69 μM and an LR 10–250 μM in colorimetric mode. Furthermore, the CeO2/CuxO-TU-OPD system has been designed for dual-mode glutathione (GSH) detection with enhanced sensitivity, achieving an LOD of 0.19 μM and an LR 0.5–10 μM in fluorescent mode; as well as an LOD of 1.24 μM and an LR 1.25–25 μM in colorimetric mode. Additionally, GSH discrimination (fluorescent mode) was successfully achieved in different biological samples, showing good consistency with the standard method. The recoveries ranged from 96.8 % to 116.7 % in serum samples and from 97.3 % to 107.7 % in cell lysates, with RSDs less than 2 %. This work not only introduced a novel approach to enhance oxidase-like activity of nanozymes but also provided an efficient field-suitable tool for enhanced dual-mode response towards TU and GSH.

Integrated recovery of copper and gold from end-of-life LEDs using two-step leaching process with volatile fatty acids

The rising demand for precious metals in clean energy technologies, coupled with their natural scarcity, has prompted the exploration of innovative processes targeting unconventional metal sources such as end-of-life electronic devices. Hydrometallurgical techniques hold promise, but environmental concerns persist, particularly concerning environmentally friendly solvent usage. This study investigates a hydrometallurgical approach, employing a two-step leaching process with mimic organic waste-derived volatile fatty acids (VFAs) for copper (Cu) extraction following gold (Au) recovery using thiourea (TU) solution from end-of-life light-emitting diodes (LEDs). Preliminary investigations with Cu powder using various organic and inorganic ligands revealed that acetic acid (AA) with hydrogen peroxide (H2O2) as an oxidant surpassed inorganic ligands at pH 4. The subsequent application of AA for Cu recovery from end-of-life LEDs resulted in a 75.36 % Cu leaching efficiency at pH 4, emphasizing VFAs’ potential in recovering Cu elements from heterogeneous electronic waste. The solid residues from AA-treated LEDs were then dissolved in a TU solution with H2O2. yielding a substantial improvement in Au recovery efficiency—94.42 % within an hour, compared to 19.47 % via direct leaching. This study demonstrates VFAs as a sustainable alternative to traditional solvents for Cu leaching, followed by Au recovery in a two-step leaching process. This approach supports a circular economy in electronic waste management by integrating biogenic waste streams for metal recovery.

Controlling Structure and Morphology of MoS2 via Sulfur Precursor for Optimized Pseudocapacitive Lithium Intercalation Hosts

AbstractMolybdenum disulfide (MoS2)‐based electrode materials can exhibit a pseudocapacitive charge storage mechanism induced by nanosized dimension of the crystalline domains, which is why control over material structure via synthesis conditions is of significance. In this study, we investigate how the use of different sulfide precursors, specifically thiourea (TU), thioacetamide (TAA), and L‐cysteine (LC), during the hydrothermal synthesis of MoS2, affects its physicochemical, and consequently, electrochemical properties. The three materials obtained exhibit distinct morphologies, ranging from micron‐sized architectures (MoS2 TU), to nanosized flakes (MoS2 TAA and LC). While all three synthesized samples exhibit pseudocapacitive Li+ intercalation properties, the capacity retention of the latter two consisting of nanosized flakes is further improved at high cycling rates. The individual charge storage properties are analyzed by operando X‐ray diffraction, dilatometry, and 3D Bode analysis, revealing a correlation between the morphology, porosity, and the electrochemical intercalation behavior of the obtained electrode materials. The results demonstrate a facile strategy to control MoS2 structure and related functionality by choice of hydrothermal synthesis precursors.

In Situ Electrochemical Interfacial Manipulation Enabling Lithiophilic Li Metal Anode with Inorganic‐Rich Solid Electrolyte Interphases for Stable Li Metal Batteries

Lithium‐metal anodes (LMAs) are the ultimate choice for realizing high‐energy‐density batteries; however, its use is hindered by problematic Li growth in the form of dendrites. To alleviate dendritic Li growth, the preparation of LMAs with a lithiophilic current collector (CC) is effective; however, applying a lithiophilic CC to LMAs is still challenging due to the manufacturing complexity involved in the separate lithiophilic treatment and lithiation processes. Herein, a facile one‐pot LMA fabrication method by utilizing thiourea (TU) as a precursor is proposed. A lithiophilic Cu2S layer is formed on Cu foam (CF) by the in situ electrochemical oxidation of TU (CuxSCF), and the lithiation of CC is performed via subsequent Li electrodeposition (Li@CuxSCF). The Cu2S on CuxSCF can lead to uniform Li deposition by providing lithiophilic sites, and it is converted to form ionic‐conductive Li2S‐rich solid electrolyte interphase layer. Resultantly, CuxSCF significantly enhances the cycling performance of LMAs compared to CF. Specifically, a LiFePO4/Li@CuxSCF full‐cell lithium‐metal battery (LMB) with a low n/p ratio (1.6) exhibits capacity retention of 95.6% at 0.5 C (220 cycles) and can maintain 85.0% of initial capacity (425 cycles, n/p = 4) at 2.0 C. LMBs with LiNi0.6Co0.2Mn0.2 and LiNi0.8Co0.1Mn0.1 also exhibit improved electrochemical performance.

Cyclic Electrogravimetry Reveals Details of Copper Electrodeposition in the Presence of Additives

Copper electroplating was studied based on cyclic voltammetry combined with a new type of acoustic microgravimetry. The instrument operates similarly to a quartz crystal microbalance with dissipation monitoring (EQCM-D), meaning that it reports shifts in resonance frequency, Δf, and half bandwidth, ΔΓ, on several overtones. Compared to the existing instruments, the time resolution was improved by a factor of 10 down to 10 ms using multifrequency lockin amplification. The frequency noise after accumulation was reduced below 10 mHz ≙ 0.12 ng/cm2 ≙ 0.14 pm (assuming ρ = 8.96 g/cm3) by modulating the electrode potential and averaging of Δf and ΔΓ. Mostly, Δf and ΔΓ are in line with the Sauerbrey prediction (Δf/n ≈const. and ΔΓ/n < -Δf/nwith n the overtone order). Small unsystematic deviations between overtones due to compressional wave effects are seen but no evidence for strong roughness or viscoelasticity. Further, the Faraday efficiency is almost unity, meaning that Δf is close to the expectations derived from the electrical current. The improved sensitivity enables to determine the time derivative of the frequency shift, which is equal to an apparent mass transfer rate that can be compared to the current directly. Again, small deviations are seen for bulk deposition and stripping. These go back to weak roughness effects most pronounced in the initial phase of bulk deposition and, also, to the presence of a Cu(I) intermediate during dissolution. When adding benzotriazole (BTA) or thiourea (TU) as plating additives, the gravimetric and the voltammetric response changes. For BTA, the deviations between mass transfer rate and current vanish indicative of decreased roughness. For TU additional features appear, related to a potential-dependent adsorption of TU and to increased underpotential deposition (UPD). In the presence of TU, the electrode-electrolyte interface displays viscoelasticity, evident by the bandwidth increases during deposition.[1] Caption: Currents, time derivatives of the frequency shift, and bandwidth shift obtained during copper electrodeposition without additives (A), in the presence of 10 µM benzotriazole (B), and in the presence of 10 µM thiourea (C). Reprinted with permission from Reference [1].

Recent Recall of Iron Reagent-Investigation of Potential Reagent Contamination and Assay Improvement Strategy.

Recently, a major manufacturer recalled several lots of iron assay reagent due to positive bias of roughly 15%-30% and the cause remains unknown. This study investigated the root cause of this positive bias and evaluated a simple practical approach to improve the assay. Performance comparison of recalled and unimpacted iron assay kits was done utilizing calibrators, quality control (QC) materials, and 42 remnant patient samples. Spectral scan and trace elements analysis of R1 and R2 reagents was performed. Copper (Cu) and thiourea (TU) spiking experiments were utilized to elucidate the cause and prevention of positive bias seen with recalled lots. Iron measurements in QC materials and patient samples using recalled reagents generated a positive bias of 17.5% and 21%, respectively. Correspondingly, the recalled R2 reagents, but not R1, showed a rise in basal absorbance along with an unanticipated presence of Cu (22.7 µg/dL) and lead (7.5 µg/L). Cu spiking to recalled and unimpacted R2 reagent intensified the reagent color besides falsely increasing its absorbance, calibration factor, and patient iron measurements. Interestingly, addition of TU (65 mmol/L) to R2 reagent from unimpacted lot prevented the short-term and prolonged Cu-induced spurious rise in calibration factor and patient iron estimations. We conclude that accidental copper contamination of R2 reagent during manufacturing could be a reason underlying the positive bias in the recalled iron reagent lots. Addition of TU in ferene-containing R2 reagent is a simple and effective means to prevent Cu-induced false elevation in iron values.

Thiourea derivatives as efficient inhibitors for the corrosion of cold rolled steel in citric acid solution: experimental and computational studies

The prediction of the corrosion inhibition properties of organic compounds from experimental and computational results is a highly interesting field. Correct understanding of substituents or electronic effects can significantly contribute to the design of efficient inhibitors. In this research article, the corrosion inhibitory performance of thiourea (TU), 1,3-dimethylthiourea (DMTU), N-ethylthiourea (ETU), and 1-p-tolylthiourea (p-TTU) in 1.0 M citric acid (H3C6H5O7) solution for cold rolled steel (CRS) was fully investigated by experimental measurements and theoretical calculations. The results show that the inhibition performance of p-TTU exhibits the best inhibition property among these four thiourea derivatives with a maximum inhibition efficiency of 97.36%. The inhibition ability follows the order of p-TTU > DMTU > ETU > TU. Potentiodynamic polarization curves indicate that all these thiourea derivatives are mixed-type inhibitors, where TU, ETU and DMTU mainly inhibit the cathodic reaction, but p-TTU effectively retards both cathodic and anodic reactions. Nyquist mainly appears a depressed capacitive loop, and the charge transfer resistance increases significantly with the addition of thiourea derivatives. The adsorption of four thiourea derivatives on CRS surface conforms to Langmuir adsorption isotherm. The micrographs from SEM and metallurgical microscopy further support the protection effectiveness of thiourea derivatives on the steel surfaces. Quantum chemical calculations and molecular dynamics simulations can well elucidate the relationship between molecular structure and inhibition efficiency for the studied thiourea derivatives.

Selective adsorption/reduction of Au in electronic waste recycling wastewater by self-assembled thiourea-crosslinked reduced graphene oxide framework ball

The increased production of electrical and electronic waste (E-waste) has resulted in a greater Au presence in E-waste than in ores. As such, it is imperative to selectively recover Au from the wastewater of E-waste. In this work, a designed self-assembled thiourea-crosslinked reduced graphene oxide framework (TU-rGOF) balls for fixed-bed reactors was successfully synthesized via a facile crosslinking reaction between thiourea (TU) and graphene oxide (GO), in which TU simultaneously transforms GO into reduced graphene oxide (rGO) during the heating process. This material exhibits excellent adsorption performance and reduced Au(III) into Au0 in aqueous solution. The adsorption efficiency reaches 95 % between pH 1 and 3. Most importantly, the TU-rGOF ball demonstrated high selectivity toward Au(III) among coexisting metal ions, including Cu(II), Pb(II), Zn(II), and Ni(II). 99 % of Au(III) at a low concentration (1 or 10 mg/L Au(III)) in a highly acidic solution (pH 2.0) was removed, yielding a maximum Langmuir adsorption capacity of 97.09 mg g−1 (TU-rGOF ball) and 833.3 mg g−1 (TU-rGO only). The best adsorption fitting to the Langmuir model also suggests monolayer coverage of Au on the TU-rGOF ball surface. Based on scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy analyses, Au(III) adsorption by TU-rGOF ball was proposed to be governed by chelation and redox. Furthermore, TU-rGOF balls also exhibited excellent selective adsorption performance (∼90 % Au adsorption at an Au concentration ∼ 1 mg/L) in real E-waste wastewater (pH = 0.07) containing significant amounts of competitive ions. This study provides novel implications for applying TU-rGOF balls to fixed-bed reactors for low-concentration Au(III) recovery from complex recycled E-waste solutions.

2-Benzylsulfanyl-1H-benzimidazole and its mixture as highly efficient corrosion inhibitors for carbon steel under dynamic supercritical CO2 flow conditions

2-Benzylsulfanyl-1H-benzimidazole(2B1BI) was synthesized and used to inhibit the corrosion of carbon steel in supercritical CO2 brine at various rotation speeds. Thiourea (TU) can improve the inhibition of 2B1BI. The corrosion inhibition mechanism and adsorption process were investigated by electrochemical techniques and theoretical calculations. The results show that 2B1BI-TU mixed corrosion inhibitors exhibit increased adsorption with strong bonds on steel, forming a denser and more persistent protective film. This film can effectively inhibit corrosive particles, slowing down both general and localized corrosion. This study explores the potential of the new inhibitor as an efficient corrosion inhibitor in challenging environmental conditions.

Thiourea improves yield and quality traits of Brassica napus L. by upregulating the antioxidant defense system under high temperature stress

High temperature stress influences plant growth, seed yield, and fatty acid contents by causing oxidative damage. This study investigated the potential of thiourea (TU) to mitigate oxidative stress and restoring seed oil content and quality in canola. The study thoroughly examined three main factors: (i) growth conditions—control and high temperature stress (35 °C); (ii) TU supplementation (1000 mg/L)—including variations like having no TU, water application at the seedling stage, TU application at seedling stage (BBCH Scale-39), water spray at anthesis stage, and TU application at anthesis stage (BBCH Scale-60); (iii) and two canola genotypes, 45S42 and Hiola-401, were studied separately. High temperature stress reduced growth and tissue water content, as plant height and relative water contents were decreased by 26 and 36% in 45S42 and 27 and 42% Hiola-401, respectively, resulting in a substantial decrease in seed yield per plant by 36 and 38% in 45S42 and Hiola-401. Seed oil content and quality parameters were also negatively affected by high temperature stress as seed oil content was reduced by 32 and 35% in 45S42 and Hiola-401. High-temperature stress increased the plant stress indicators like malondialdehyde, H2O2 content, and electrolyte leakage; these indicators were increased in both canola genotypes as compared to control. Interestingly, TU supplementation restored plant performance, enhancing height, relative water content, foliar chlorophyll (SPAD value), and seed yield per plant by 21, 15, 30, and 28% in 45S42; 19, 13, 26, and 21% in Hiola-401, respectively, under high temperature stress as compared to control. In addition, seed quality, seed oil content, linoleic acid, and linolenic acid were improved by 16, 14, and 22% in 45S42, and 16, 11, and 23% in Hiola-401, as compared to control. The most significant improvements in canola seed yield per plant were observed when TU was applied at the anthesis stage. Additionally, the research highlighted that canola genotype 45S42 responded better to TU applications and exhibited greater resilience against high temperature stress compared to genotype Hiola-401. This interesting study revealed that TU supplementation, particularly at the anthesis stage, improved high temperature stress tolerance, seed oil content, and fatty acid profile in two canola genotypes.

Study on the inhibition mechanism of corrosion under inert deposit-covered X65 steel by three corrosion inhibitors

In order to solve the problem of under-deposit corrosion caused by typical inert minerals in oil and gas fields, three corrosion inhibitors with small molecular weight thiourea (TU), oil-soluble alkyl imidazoline (IM) and water-soluble thiourea imidazoline (TAI) were selected. The corrosion inhibition effect and mechanism of the them under SiO2 and CaCO3 deposit were studied by surface analysis, electrochemical analysis and theoretical calculations. The results show that TU, IM and TAI can adsorb on the metal surface through the deposits, and the corrosion inhibition efficiency is η(TAI) > η(TU) > η(IM). TU and TAI are mixed corrosion inhibitors that inhibit both the cathode and the anode reactions, and the thiourea group in TU and TAI can form coordination chemical bonds with the empty d orbital of iron atoms as electron-rich regions. Due to hydrophobic groups, the adsorption film formed by TAI on the metal surface is denser. However, it is difficult for IM to form a continuous protective corrosion inhibitor film under the two deposits, so it shows poor corrosion inhibition performance.

Dual Noncovalent Binding Modes Enabled via Single Thiourea Motif: An Emerging Arsenal for Supramolecular Polymeric Nanomedicine

AbstractThe structural rigidity of thiourea (TU) motifs has made them useful in supramolecular (bio)materials. However, the role of the TU motif in a single system endowing dual noncovalent interactions, i.e., Hydrogen‐bonding (H‐bonding) association and metal‐coordination interaction, to afford nanomedicine is still unexplored. Herein a smart supramolecular polymeric nanomedicine constructed via TU motifs privileged dual noncovalent interactions, toward synergistic chemo/chemodynamic (CT/CDT) cancer therapy is reported. The study first synthesized a six‐arm star‐shaped amphiphilic polymer vehicle containing pendant TU motifs, poly(acylthiourea‐co‐oligo(ethylene glycol) ethyl acrylate)6 (P(TU‐co‐OEGEA)6), followed by addressing both H‐bonding association and metal‐coordination to fabricate supramolecular nanomedicine (e.g., Dox/Cu@P(TU‐co‐OEGEA)6). Structural privilege and functional diversity of TU motifs constitute an outstanding scaffold, not only offering an H‐bonding site to associate doxorubicin (Dox) but also acting as a ligand to coordinate copper (Cu). Thereby, one TU motif can enable dual noncovalent binding modes, triggering multiple curative outcomes. TU/Dox and TU/Cu noncovalent interactions can induce intermolecular configuration, yielding prompted cargo loading and in vivo stability. Moreover, benefiting from pH‐responsive Dox release and Fenton‐like copper redox chemistry, accompanied by Dox‐induced intratumoral H2O2 elevation and prompted •OH generation, synergistic CT/CDT with extraordinary anti‐tumor efficacy is indeed accomplished. This work provides a new paradigm using TU motifs regulated dual supramolecular forces to meet therapeutic goals.

Chromium speciation in water using magnetic polyaniline nanoparticles coupled with microsampling injection-flame atomic absorption spectroscopy.

The chromium speciation procedure was optimized using magnetic polyaniline nanoparticles (Fe3O4@PANI NPs) solid-phase extraction coupled with microsampling injection-flame atomic absorption spectrometry (MIS-FAAS). Chromium speciation was successfully achieved by Fe3O4@PANI NPs at pH 8.0. The recoveries obtained for Cr(III) and Cr(VI) were above 95% and under 5%, respectively. Recoveries of over 95% for Cr(III) from 40.0 mL of the sample were obtained using 25 mg Fe3O4@PANI NPs and 500 μL of 0.2% (w/v) thiourea (TU) solution prepared in 2 mol L-1 HCl as eluent. Total chromium as Cr(III) was extracted quantitatively after reducing the Cr(VI) to Cr(III). The linear range, detection limit, preconcentration factor, and precision of the optimized method for Cr(III) in aqueous solution were 2.5-94.0 μg L-1, 0.335 μg L-1, 80, and 3.07%, respectively. The validation of the method was controlled using SPS-WW2 Batch 114 wastewater and BCR-715 industrial wastewater as standard reference materials (SRMs) for environmental water, and the obtained results were in close agreement with the certified values.

Efficient selective uptake of Hg(Ⅱ) using a porous organic polymer rich in N and S atoms

The escalating issue of mercury (II) ions (Hg2+) pollution in water, primarily due to human activities, poses a significant environmental and health risk. Addressing the urgent need for efficient Hg2+ removal, this study introduces a novel porous organic polymer (TpTHU) synthesized through Schiff base condensation of thiourea (THU) and 1,3,5-Triformylphloroglucinol (Tp). TpTHU, enriched with sulfur and nitrogen, facilitates soft–soft interaction with Hg2+, offering a potent solution for mercury contamination. Our experimental results demonstrate TpTHU's remarkable adsorption capacity for Hg2+, reaching 1250 mg/g, attributed to its dense complexation sites. The adsorption behavior aligns well with the Brouers-Sotolongo model. Notably, TpTHU achieves 99.25% mercury removal within 120 min over a broad pH range (4 to 10), underscoring its rapid action. Additionally, in fixed-bed column experiments, TpTHU effectively lowers Hg2+ concentrations in industrial wastewater from 10.0 mg/L to below 5 μg/L, surpassing industrial emission standards. Through XPS analysis and density functional theory calculations, we elucidate the adsorption mechanism, affirming TpTHU's efficiency. With its straightforward synthesis, high efficacy, and excellent reusability, TpTHU emerges as a promising candidate for mitigating Hg2+ pollution in industrial wastewater.

Thiourea leaching of gold: Elucidating the mechanism of arsenopyrite catalyzed thiourea oxidation by Fe3+ and the beneficial role of oxalate through experimental and density functional theory (DFT) investigations

The combination of bio-oxidation pretreatment of refractory sulfide gold ore and thiourea leaching is a suitable method for gold extraction due to its environmental friendliness and compatibility in the two leaching systems. Arsenopyrite is an important auriferous sulfide mineral where the encapsulated gold can be effectively exposed by bioleaching pretreatment. The issue of high thiourea (TU) consumption, however, severely hinders the commercial application of this technology. In this paper, the effect of arsenopyrite on gold leaching in an acidic TU solution was investigated. Leaching results showed that the presence of arsenopyrite seriously impeded TU leaching of gold represented as the much decrease in gold dissolution and TU stability. The dominant cause for the detrimental effect of arsenopyrite was that arsenopyrite can catalyze the oxidation of TU by Fe3+ and thus bring about high TU consumption, further resulting in the marked deterioration of TU dissolution of gold. The catalytic mechanism is believed to be that TU adsorbs on arsenopyrite surface and then electrons transfer from TU to the oxidant Fe3+ through the conduction bands of arsenopyrite. Oxalate was used to improve TU stability and gold dissolution, and its mechanism was proposed as follows: oxalate not only weakened the interaction between Fe3+ and TU through complexing with Fe3+ but also competed with TU to absorb on the arsenopyrite surface, which decreased the TU adsorption. Besides, the formation of Fe-oxalate complexes, as the terminal electron acceptor, distinctly reduced the oxidation capacity of Fe3+, thus alleviating the catalytic effect of arsenopyrite on TU oxidation by Fe3+.