Enzyme-Inspired Ligand Engineering of Gold Nanoclusters for Electrocatalytic Microenvironment Manipulation.

Natural enzymes intricately regulate substrate accessibility through specific amino acid sequences and folded structures at their active sites. Achieving such precise control over the microenvironment has proven to be challenging in nanocatalysis, especially in the realm of ligand-stabilized metal nanoparticles. Here, we use atomically precise metal nanoclusters (NCs) as model catalysts to demonstrate an effective ligand engineering strategy to control the local concentration of CO2 on the surface of gold (Au) NCs during electrocatalytic CO2 reduction reactions (CO2RR). The precise incorporation of two 2-thiouracil-5-carboxylic acid (TCA) ligands within the pocket-like cavity of [Au25(pMBA)18]- NCs (pMBA = para-mercaptobenzoic acid) leads to a substantial acceleration in the reaction kinetics of CO2RR. This enhancement is attributed to a more favorable microenvironment in proximity to the active site for CO2, facilitated by supramolecular interactions between the nucleophilic Nδ- of the pyrimidine ring of the TCA ligand and the electrophilic Cδ+ of CO2. A comprehensive investigation employing absorption spectroscopy, mass spectrometry, isotopic labeling measurements, electrochemical analyses, and quantum chemical computation highlights the pivotal role of local CO2 enrichment in enhancing the activity and selectivity of TCA-modified Au25 NCs for CO2RR. Notably, a high Faradaic efficiency of 98.6% toward CO has been achieved. The surface engineering approach and catalytic fundamentals elucidated in this study provide a systematic foundation for the molecular-level design of metal-based electrocatalysts.

Elucidation of the genetic determination of body weight and size in Chinese local chicken breeds by large-scale genomic analyses.

BACKGROUND: Body weight and size are important economic traits in chickens. While many growth-related quantitative trait loci (QTLs) and candidate genes have been identified, further research is needed to confirm and characterize these findings. In this study, we investigate genetic and genomic markers associated with chicken body weight and size. This study provides new insights into potential markers for genomic selection and breeding strategies to improve meat production in chickens. METHODS: We performed whole-genome resequencing of and Wenshang Barred (WB) chickens (n = 596) and three additional breeds with varying body sizes (Recessive White (RW), WB, and Luxi Mini (LM) chickens; (n = 50)). We then used selective sweeps of mutations coupled with genome-wide association study (GWAS) to identify genomic markers associated with body weight and size. RESULTS: We identified over 9.4 million high-quality single nucleotide polymorphisms (SNPs) among three chicken breeds/lines. Among these breeds, 287 protein-coding genes exhibited positive selection in the RW and WB populations, while 241 protein-coding genes showed positive selection in the LM and WB populations. Genomic heritability estimates were calculated for 26 body weight and size traits, including body weight, chest breadth, chest depth, thoracic horn, body oblique length, keel length, pelvic width, shank length, and shank circumference in the WB breed. The estimates ranged from 0.04 to 0.67. Our analysis also identified a total of 2,522 genome-wide significant SNPs, with 2,474 SNPs clustered around two genomic regions. The first region, located on chromosome 4 (7.41-7.64 Mb), was linked to body weight after ten weeks and body size traits. LCORL, LDB2, and PPARGC1A were identified as candidate genes in this region. The other region, located on chromosome 1 (170.46-171.53 Mb), was associated with body weight from four to eighteen weeks and body size traits. This region contained CAB39L and WDFY2 as candidate genes. Notably, LCORL, LDB2, and PPARGC1A showed highly selective signatures among the three breeds of chicken with varying body sizes. CONCLUSION: Overall this study provides a comprehensive map of genomic variants associated with body weight and size in chickens. We propose two genomic regions, one on chromosome 1 and the other on chromosome 4, that could helpful for developing genome selection breeding strategies to enhance meat yield in chickens.

Application of photo-crosslinkable gelatin methacryloyl in wound healing.

Wound healing is a complex and coordinated biological process easily influenced by various internal and external factors. Hydrogels have immense practical importance in wound nursing because of their environmental moisturising, pain-relieving, and cooling effects. As photo-crosslinkable biomaterials, gelatine methacryloyl (GelMA) hydrogels exhibit substantial potential for tissue repair and reconstruction because of their tunable and beneficial properties. GelMA hydrogels have been extensively investigated as scaffolds for cell growth and drug release in various biomedical applications. They also hold great significance in wound healing because of their similarity to the components of the extracellular matrix of the skin and their favourable physicochemical properties. These hydrogels can promote wound healing and tissue remodelling by reducing inflammation, facilitating vascularisation, and supporting cell growth. In this study, we reviewed the applications of GelMA hydrogels in wound healing, including skin tissue engineering, wound dressing, and transdermal drug delivery. We aim to inspire further exploration of their potential for wound healing.

Lithium aluminum hydride Li3AlH6: new insight into the anode material for liquid-state lithium-ion batteries.

Metal hydrides have been demonstrated as one of the promising high-capacity anode materials for Li-ion batteries. Herein, we report the electrochemical properties and lithium storage mechanism of a Li-rich complex metal hydride (Li3AlH6). Li3AlH6 exhibits a lithiation capacity of ∼1729 mAh/g with a plateau potential of ∼0.33 V vs. Li+/Li at the first discharge cycle. Experimental results demonstrate that Li3AlH6 is converted into LiH and LiAl in the initial electrochemical lithiation process. In addition, Li3AlH6 also possesses a good cycling stability that 71 % of the second discharge capacity is retained after 20 cycles. More importantly, the cycling performance of Li3AlH6 can be improved to 100 cycles via adjusting electrolyte composition. This study provides a new approach for developing the lithium storage properties of anode materials for Li-ion batteries.

HELQ as a DNA helicase: Its novel role in normal cell function and tumorigenesis (Review).

Helicase POLQ­like (HELQ or Hel308), is a highly conserved, 3'­5' superfamily II DNA helicase that contributes to diverse DNA processes, including DNA repair, unwinding, and strand annealing. HELQ deficiency leads to subfertility, due to its critical role in germ cell stability. In addition, the abnormal expression of HELQ has been observed in multiple tumors and a number of molecular pathways, including the nucleotide excision repair, checkpoint kinase 1­DNA repair protein RAD51 homolog 1 and ATM/ATR pathways, have been shown to be involved in HELQ. In the present review, the structure and characteristics of HELQ, as well as its major functions in DNA processing, were described. Molecular mechanisms involving HELQ in the context of tumorigenesis were also described. It was deduced that HELQ biology warrants investigation, and that its critical roles in the regulation of various DNA processes and participation in tumorigenesis are clinically relevant.

Icariin activates far upstream element binding protein 1 to regulate hypoxia-inducible factor-1α and hypoxia-inducible factor-2α signaling and benefits chondrocytes.

Icariin (ICA) is a typical flavonoid glycoside derived from epimedium plants. It has both anabolic and anti-catabolic effects to improve bone mineral density and reduce bone microstructural degradation. However, the effect and underlying mechanism of ICA on the proliferation and metabolism of chondrocyte and synthesis of extracellular matrix are still unclear. This study aimed to investigate the role and regulation of far upstream element binding protein 1 (FUBP1) in chondrocytes treated with ICA to maintain homeostasis and suppress inflammatory responses. In the study, the effect of ICA on chondrocytes with overexpressed or silenced FUBP1 was detected by the MTS and single-cell cloning methods. The expression of hypoxia-inducible factor-1/2α (HIF-1/2α), FUBP1, matrix metalloproteinase (MMP)9, SRY-box transcription factor 9 (SOX9), and type II collagen (Col2α) in ATDC5 cells, a mouse chondrogenic cell line, treated with ICA was evaluated by immunoblotting. Western blotting revealed 1 µM ICA to have the most significant effect on chondrocytes. Alcian blue staining and colony formation assays showed that the promoting effect of ICA was insignificant in FUBP1-knockdown cells (P > 0.05) but significantly enhanced in FUBP1-overexpressed cells (P < 0.05). Western blot results from FUBP1-knockdown cells treated with or without ICA showed no significant difference in the expression of FUBP1, HIF-1/2α, MMP9, SOX9, and Col2α proteins, whereas the same proteins showed increased expression in FUBP1-overexpressed chondrocytes; moreover, HIF-2α and MMP9 expression was significantly inhibited in FUBP1-knockdown chondrocytes (P < 0.05). In conclusion, as a bioactive monomer of traditional Chinese medicine, ICA is beneficial to chondrocytes.

Role of Rituximab in Treatment of Patients With Primary Central Nervous System Lymphoma (PCNSL): A Systematic Review and Meta-Analysis.

Primary central nervous system lymphoma (PCNSL) is a rare form of non-Hodgkin's lymphoma involving the brain, cerebrospinal fluid, spinal cord and eyes. Rituximab has played a prominent role in the treatment of non-Hodgkin's B-cell lymphomas, including aggressive diffuse large B lymphoma. However, as a macromolecular drug, the role of rituximab in the treatment of PCNSL has been controversial. In this systematic review and meta-analysis, we evaluated the role of rituximab in the treatment of PCNSL. We searched articles in the following electronic databases including PubMed, Embase, Cochrane Library, Web of Science, and ClinicalTrials.gov until October 20, 2022.We included 11 studies (3 RCTS and 8 retrospective studies) with a total of 1182 patients. We extracted the baseline characteristics and outcomes of the studies and assessed the risk of bias, then used Review Manager 5.4 for this meta-analysis. The primary outcomes included complete response rate (CR), overall survival (OS), and progression-free survival (PFS). Odds ratios (ORS) and corresponding 95% confidence intervals (CIS) for the primary outcome were analyzed and compared. The results of our statistical analysis show that the use of rituximab was closely correlated with a higher CR(OR 1.70,95%CI 1.17-2.46, P = .005), 3-year OS (OR 2.40, 95%CI 1.53-3.77, P = .0001), 5-year OS (OR 2.75, 95%CI 1.68-4.49, P < .0001), 3-year PFS(OR 4.42, 95%CI 1.15-16.97, P < .0001), 5-year PFS(OR 1.97, 95%CI 1.39-2.78, P = .0001).These results suggest that rituximab may have a positive impact on the prognosis of patients with PCNSL, and may be helpful in the determination of treatment plan for patients with PCNSL.

Ligand effect on switching the rate-determining step of water oxidation in atomically precise metal nanoclusters.

The ligand effects of atomically precise metal nanoclusters on electrocatalysis kinetics have been rarely revealed. Herein, we employ atomically precise Au25 nanoclusters with different ligands (i.e., para-mercaptobenzoic acid, 6-mercaptohexanoic acid, and homocysteine) as paradigm electrocatalysts to demonstrate oxygen evolution reaction rate-determining step switching through ligand engineering. Au25 nanoclusters capped by para-mercaptobenzoic acid exhibit a better performance with nearly 4 times higher than that of Au25 NCs capped by other two ligands. We deduce that para-mercaptobenzoic acid with a stronger electron-withdrawing ability establishes more partial positive charges on Au(I) (i.e., active sites) for facilitating feasible adsorption of OH- in alkaline media. X-ray photo-electron spectroscopy and theoretical study indicate a profound electron transfer from Au(I) to para-mercaptobenzoic acid. The Tafel slope and in situ Raman spectroscopy suggest different ligands trigger different rate-determining step for these Au25 nanoclusters. The mechanistic insights reported here can add to the acceptance of atomically precise metal nanoclusters as effective electrocatalysts.

Functionalized Ag with Thiol Ligand to Promote Effective CO2 Electroreduction.

It is challenging while critical to develop efficient catalysts that can achieve both high current density and high energy efficiency for electrocatalytic CO2 reduction (CO2R). Herein, we report a strategy of tailoring the surface electronic structure of an Ag catalyst via thiol ligand modification to improve its intrinsic activity, selectivity, and further energy efficiency toward CO2R. Specifically, interconnected Ag nanoparticles with residual thiol ligands on the surface were prepared through electrochemical activation of a thiol-ligand-based Ag complex. When it was used as a catalyst for CO2R, the thiol-ligand modified Ag exhibited high CO selectivity (>90%) throughout a wide electrode-potential range; furthermore, high cathodic energy efficiencies of >90% and >70% were obtained for CO formation at high current densities of 150 and 750 mA cm-2, respectively, outperforming the state-of-the-art Ag-based electrocatalysts for CO2 to CO conversion. The first-principle calculations on the reaction energetics suggest that the binding energies of the key intermediate -*COOH on Ag are optimized by the adsorbed thiol ligand, thus favoring CO formation while suppressing the competing H2 evolution. Our findings provide a rational design strategy for CO2 reduction electrocatalyst by electronic modulation through surface-adsorbed ligands.

CD20 expression is closely associated with Epstein-Barr virus infection and an inferior survival in nodular sclerosis classical Hodgkin lymphoma.

Background: Nodular sclerosis classical Hodgkin lymphoma (NSCHL) is a rare disease in which Epstein-Barr virus (EBV) and CD20 can be detected. The clinical significance of EBV infection, CD20 expression and their relationship are still unclear in NSCHL presently. The aim of this research was to systematically explore the clinical significance of EBV infection, expression of CD20 and their relationship in NSCHL. Methods: 109 NSCHL patients diagnosed in Qingdao University's Affiliated Hospital were chosen from January 2010 to July 2019, and the clinical and survival data of all patients were collected retrospectively. Results: Among 109 patients, 33 patients were assigned to the group of EBV-positives, following the results of the EBV-encoded RNA (EBER1). Compared with EBV-negative group patients, those in the group of EBV-positive were older (P=0.004) and their ß2-microglobulin (ß2-MG) levels were higher (P=0.006). The CD20 positivity rate in the group of EBV-positive was substantially higher than that in the EBV-negative group (54.5% vs 27.6%, P=0.007). Among 109 patients, EBV+ and CD20+ double positive patients acquired the least overall survival (OS), and patients with EBV- and CD20- double negative had the best OS (P < 0.001). Although old age, gender, EBV infection and CD20 positive were the risk factors for OS in NSCHL, multivariate analysis showed that CD20 positivity was the only characteristic that showed to be an independent risk factor for OS in NSCHL patients. Conclusion: CD20 was found to be strongly expressed in NSCHL patients who had been infected with EBV, and it was found to be an independent risk factor for NSCHL patients' survival.

Aggregation-Induced Emission of Gold Nanoclusters by Ionic Liquids for White Light-Emitting Diode and Multiple-Ion Probe Applications.

White light-emitting diodes (WLEDs) require stable luminophores with bright emission, a large Stokes shift, and good processability. Herein, we fabricate WLEDs on the basis of synergetic aggregation-induced emission (AIE) of Au nanoclusters (NCs) induced by ionic liquids. Au NCs with orange emission at 615 nm are electrostatically bonded to 1-ethyl-3-methyl-imidazolium acetate (EmimOAc). The electrostatic bonding not only introduces complementary blue emission (from EmimOAc) into Au NCs but also enhances cluster emission via an intercluster AIE mechanism. Overall white emission of Au NC-EmimOAc composites can be further improved by their encapsulation into nanogels templated by cationic chitosan. Color conversion films constructed from these nanogels manifest ultrabright white emission on a commercial GaN ultraviolet LED chip, featuring a CIE 1931 color coordinate of (0.366, 0.368) and greatly enhanced mechanical strength. By properly selecting ionic liquids, we are also able to achieve multiple-ion detection of Cu2+, Sn2+, and Fe3+.

FBP1 knockdown decreases ovarian cancer formation and cisplatin resistance through EZH2-mediated H3K27me3.

Worldwide, ovarian cancer (OC) is the seventh common cancer and the second most common cause of cancer death in women. Due to high rates of relapse, there is an urgent need for the identification of new targets for OC treatment. The far-upstream element binding protein 1 (FBP1) and enhancer of zeste homolog 2 (EZH2) are emerging proto-oncogenes that regulate cell proliferation and metastasis. In the present study, Oncomine data analysis demonstrated that FBP1 was closely associated with the development of OC, and The Cancer Genome Atlas (TCGA) data analysis indicated that there was a positive correlation between FBP1 and EZH2 in ovarian tissues. Moreover, we found that FBP1 knockdown suppressed tumor formation in nude mice and cisplatin resistance of OC cells, but the role of FBP1 in the cisplatin resistance of OC cells remained unclear. In addition, we verified physical binding between FBP1 and EZH2 in OC cells, and we demonstrated that FBP1 knockdown enhanced cisplatin cytotoxicity in OC cells and down-regulated EZH2 expression and trimethylation of H3K27. These results suggested that FBP1 increases cisplatin resistance of OC cells by up-regulating EZH2/H3K27me3. Thus, FBP1 is a prospective novel target for the development of OC treatment.

Surface Plasmon-Enhanced NIR-II Fluorescence in a Multilayer Nanoprobe for Through-Skull Mouse Brain Imaging.

Fluorescence imaging in the second near-infrared window (NIR-II, 1000-1700 nm) holds great potential for the accurate visualization of deeply located biological structures in vivo. However, the weak fluorescence of current NIR-II fluorophores remains a long-standing challenge for the ever-growing imaging demand. Here, we describe a surface plasmon-enhanced NIR-II fluorescence strategy by incorporating silica-coated gold nanorods (GNRs) and polymer dots (Pdots) into a multilayer nanostructure. Precise manipulation of the silica spacing layer thickness signifies an optimum distance of 8.6 nm, where an enhancement factor of up to 6.4 is achieved in the NIR-II imaging window. The surface plasmon enhancement approach is successfully extended to several types of Pdots fluorophores with NIR-II emission. We finally perform outer-layer encapsulation and PEGylation for the multilayer probes and demonstrate surface plasmon-enhanced NIR-II fluorescence for mouse brain imaging through the skull, which exhibits a refined signal-to-background ratio and penetration depth as compared to the clinically approved ICG dye.

Expression and Clinical Significance of Th1/Th2/Th17 Cytokines and Lymphocyte Subsets in PCNSL.

Purpose: Primary central nervous system lymphoma (PCNSL) responds favorably to radiation, chemotherapy and targeted drug therapy. However survival is usually worse, the treatment-related drug resistance and recurrence are still clinical problems to be solved urgently. Studies have shown that cytokines are expressed in varying degrees in patients with lymphoma, which is significantly related to the progression, poor prognosis and drug resistance of lymphoma. We explore the expression and clinical significance of Th1/Th2/Th17 cytokines and lymphocyte subsets in patients with PCNSL to provide a more sufficient theoretical basis for its diagnosis and treatment. Patients and Methods: We measured and analysed the levels of Th1/Th2/Th17 cytokines and the distribution of lymphocyte subsets (including Treg cells, CD3+, CD4+, CD8+, CD19+, and CD4+/CD8+) in 39 patients with PCNSL and 96 patients with diffuse large B-cell lymphoma (DLBCL) without central nervous system involvement. The cytokines of 13 healthy people and the lymphocyte subsets of 27 healthy people were measured as the control group. Results: We found a significant difference in the level of Th1/Th2/Th17 cytokines and lymphocyte subsets between PCNSL and healthy controls, especially IL-2, after treatment, which was significantly higher than before treatment (p<0.01). However, the level of CD19+ and CD4+/CD8+ decreased while CD8+ and CD3+ increased after treatment (regardless of whether the treatment was effective), and the difference was statistically significant. In addition, our analysis of different prognostic factors found that HD-MTX-based chemotherapy appears to have a longer progression-free survival and overall survival than osimertinib-based chemotherapy. Conclusion: There are significant differences in Th1/Th2/Th17 cytokines and lymphocyte subsets among PCNSL, DLBCL, and healthy controls, and their detection is helpful for the diagnosis, treatment, and prognosis of PCNSL. HD-MTX-based chemotherapy may still be the first choice for PCNSL.

The Role of Flavonoids in the Osteogenic Differentiation of Mesenchymal Stem Cells.

Mesenchymal stem cells (MSCs) play an important role in developing bone tissue engineered constructs due to their osteogenic and chondrogenic differentiation potential. MSC-based tissue engineered constructs are generally considered a safe procedure, however, the long-term results obtained up to now are far from satisfactory. The main causes of these therapeutic limitations are inefficient homing, engraftment, and directional differentiation. Flavonoids are a secondary metabolite, widely existed in nature and have many biological activities. For a long time, researchers have confirmed the anti-osteoporosis effect of flavonoids through in vitro cell experiments, animal studies. In recent years the regulatory effects of flavonoids on mesenchymal stem cells (MSCs) differentiation have been received increasingly attention. Recent studies revealed flavonoids possess the ability to modulate self-renewal and differentiation potential of MSCs. In order to facilitate further research on MSCs osteogenic differentiation of flavonoids, we surveyed the literature published on the use of flavonoids in osteogenic differentiation of MSCs, and summarized their pharmacological activities as well as the underlying mechanisms, aimed to explore their promising therapeutic application in bone disorders and bone tissue engineered constructs.

Multicolor Photoacoustic Volumetric Imaging of Subcellular Structures.

Photoacoustic imaging (PAI) has been widely used in multiscale and multicontrast imaging of biological structures and functions. Optical resolution photoacoustic microscopy (OR-PAM), an emerging submodality of PAI, features high lateral resolution and rich optical contrast, indicating great potential in visualizing cellular and subcellular structures. However, three-dimensional (3D) imaging of subcellular structures using OR-PAM has remained a challenge due to the limited axial resolution. In this study, we propose a multicolor 3D photoacoustic microscopy with high lateral/axial resolutions of 0.42/2 and 0.5/2.5 µm at 532 and 780 nm excitation, respectively. Owing to the significantly increased axial resolution, we could visualize the volumetric subcellular structures of melanoma cells using intrinsic contrast. In addition, we carried out multicolor imaging of labeled microtubules/clathrin-coated pits (CCP) and microtubules/mitochondria, respectively, with one scanning by using two different excitation wavelengths. The internal connections between different subcellular structures are revealed by quantitatively comparing the spatial distributions of microtubules/CCP and microtubules/mitochondria in a single cell. Current results suggest that the proposed OR-PAM may serve as an efficient tool for subcellular and cytophysiological studies.

Long-Term In Vivo Glucose Monitoring by Polymer-Dot Transducer in an Injectable Hydrogel Implant.

Optical sensors have attracted a great deal of interest for glucose detection. However, their practical applications for continuous glucose monitoring are still constrained by operational reliability in subcutaneous tissues. Here, we show an implantable hydrogel platform embedded with luminescent polymer dots (Pdots) for sensitive and long-term glucose monitoring. We use Pdot transducer in a polyacrylamide hydrogel matrix to construct an implantable platform. The hydrogel-Pdot transducer showed bright luminescence with ratiometric response to glucose changes. The in vitro and in vivo sensitivities of the hydrogel implant were enhanced by varying the enzyme concentration and injection volume. After implantation, the hydrogel with Pdot transducer remained at the implanted site without migration for 1 month and can be removed from the subcutaneous tissue for further analysis. Our results indicate that the hydrogel-Pdot platform maintains the intrinsic sensing property with excellent stability during 1 month implantation, while fibrous capsule formation on the implant in some cases needs to be solved for long-term continuous glucose monitoring.

Prognostic value of circulating tumor DNA in lymphoma: a meta-analysis.

Circulating tumor DNA (ctDNA) can be used to evaluate the prognosis of lymphoma. However, there is no uniform consensus about the mechanistic role that ctDNA plays in the prognosis of lymphoma. This meta-analysis explores the prognostic value of ctDNA in lymphoma, especially in diffuse large B cell lymphoma (DLBCL). All relevant reports published as of May 14, 2020, were retrieved by searching electronic databases in Pubmed, Embase and Cochrane Library. The prognostic value of ctDNA was evaluated using meta-analysis. Revman 5.3 software was used for prognostic data extraction and analysis. Eight studies, including a total of 767 lymphoma patients, were enrolled in this meta-analysis. Five out of eight studies investigated the association between ctDNA levels and progression-free survival (PFS) in 501 lymphoma patients, indicating that high levels of ctDNA were significantly associated with poor PFS (HR 2.24, 95%CI: 1.63-3.08, P < 0.00001). We conducted a subgroup analysis of 379 patients with DLBCL across three of the studies and came to the same conclusion (HR 2.01, 95%CI: 1.42-2.85, P < 0.0001). Two studies with a total of 192 lymphoma patients described the association between ctDNA levels and event-free survival (EFS), showing that high levels of ctDNA were also associated with adverse EFS (HR 4.53, 95%CI: 1.79-11.47, P = 0.001). The remaining two studies analyzed the potential clinical value of ctDNA for predicting the overall survival time (OS) of DLBCL patients, demonstrating that high levels of ctDNA correlated with inferior OS (HR 3.09, 95%CI: 1.50-6.35, P = 0.002). Our meta-analysis showed that high levels of ctDNA were associated with poor prognosis in patients with lymphoma, especially DLBCL.

Surface Engineering Assisted Size and Structure Modulation of Gold Nanoclusters by Ionic Liquid Cations.

Surface modification induced core size/structure change is a recent discovery in inorganic nanoparticles research, and has rarely been revealed at the molecular level. Here, we exemplify with atomically precise Au nanoclusters (NCs) that proper surface modification can selectively stabilize the desired Au0 core, conducive to the formation of size/structure-controlled Au NCs. Leveraging π-π enhanced ion-pairing interactions, ionic liquid (IL) cations are bonded to AuI -thiolate complexes. The hydrophobic-hydrophobic interactions between IL cations subsequently provide a good mechanism to prolong the size of the AuI -thiolate complexes, selectively producing small-sized Au NCs upon reduction. Through combined control over the structure and concentration of IL cations, pH and solvent polarity, we are able to produce atomically precise Au NCs with customizable size, atomic packing structure, and surface chemistry. This work also provides a facile means to integrate/synergize the materials functionalities of Au NCs and ILs, increasing their acceptance in diverse fields.

Electrocatalysis of gold-based nanoparticles and nanoclusters.

Gold (Au)-based nanomaterials, including nanoparticles (NPs) and nanoclusters (NCs), have shown great potential in many electrocatalytic reactions due to their excellent catalytic ability and selectivity. In recent years, Au-based nanostructured materials have been considered as one of the most promising non-platinum (Pt) electrocatalysts. The controlled synthesis of Au-based NPs and NCs and the delicate microstructure adjustment play a vital role in regulating their catalytic activity toward various reactions. This review focuses on the latest progress in the synthesis of efficient Au-based NP and NC electrocatalysts, highlighting the relationship between Au nanostructures and their catalytic activity. This review first discusses the parameters of Au-based nanomaterials that determine their electrocatalytic performance, including composition, particle size and architecture. Subsequently, the latest electrocatalytic applications of Au-based NPs and NCs in various reactions are provided. Finally, some challenges and opportunities are highlighted, which will guide the rational design of Au-based NPs and NCs as promising electrocatalysts.