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A solid phase microextraction fiber (SPME) with gold nanoparticles coatings (AuNPs) was prepared based on stainless-steel fiber by chemical deposition. In order to greatly increase the specific surface area of the stainless-steel fiber, the porous fiber were formed by hydrofluoric acid treatment and aqua regia-dopamine treatment after AuNPs coating. Thus, the porous gold coated SPME with large specific surface area, strong bonding and controllable thickness were prepared. Scanning electron microscopy (SEM) and elements analysis were used to characterize. Under the optimized conditions, the prepared fibers exhibited good precision, wide linear ranges, acceptable recoveries, and low limits of detection for lamotrigine. The results verified that this novel coating was a promising sorbent for extraction and trace analysis of lamotrigine in complex matrixes.

The onset and progression of many cancers, including gastric cancer (GC), are strongly influenced by cell senescence. Numerous studies have demonstrated that long non-coding RNA (lncRNA) impacts cell senescence, thus affecting cancer progression. However, it is not possible to develop a relevant predictive model for GC owing to the absence of a cell senescence-linked lncRNA. Since lncRNAs are linked to cellular senescence, the goal of this work was to create a prognostic signature for stomach adenocarcinoma (STAD) patients utilizing these lncRNAs.Through the Pearson correlation, variance, and univariate Cox regression analyses, the cellular senescence lncRNAs that were related to the disease prognosis could be successfully identified. Using the least absolute shrinkage and selection operator (LASSO) regression algorithm, a predictive model that utilized the 11 cellular senescence-linked lncRNAs was constructed. Kaplan-Meier (KM) survival and the receiver operating characteristic (ROC) curve analyses, were employed for assessing the prognostic performance of the proposed model. In addition, ESTIMATE analysis of the low- and high-risk subtypes for the infiltration of various immune cells was carried out. Additionally, the CIBERSORT algorithm was utilized for investigating the infiltration status of numerous immune cells in both groups, while the expression of the immune checkpoint genes in the two groups, was also determined.In this study, a new prognostic model was constructed using 11 cellular senescence-related lncRNAs. The findings revealed that the OS status of the patients in the low-risk group (category) was significantly higher compared to the high-risk category (P0.001). The 1-year ROC-area under the curve (AUC) values for the risk score in the training group was 0.714, while the AUC value for the test and comprehensive groups were recorded to be 0.666 and 0.695, respectively, which were obviously due to stage, grade, age, etc. And based on univariate [hazard ratio (HR): 1.435; P0.001; 95% confidence interval (CI): 1.295-1.589] and multivariate analyses (P0.001; 95% CI: HR: 1.387; 1.247-1.543), it was noted that risk scores were effectively employed as a patient-independent prognostic factor.Taken together, these results suggest that cellular senescence-related lncRNAs are likely to be valuable prognostic markers for GC. They also reflect the situation of the STAD immune microenvironment and may provide direction for future GC treatment.

A temperature-controlled electrochemical sensor was constructed based on a composite membrane composed of temperature-sensitive polymer poly (N-isopropylacrylamide) (PNIPAM) and carboxylated multi-walled carbon nanotubes (MWCNTs-COOH). The sensor has good temperature sensitivity and reversibility in detecting Dopamine (DA). At low temperatures, the polymer is stretched to bury the electrically active sites of carbon nanocomposites. Dopamine cannot exchange electrons through the polymer, representing an “OFF” state. On the contrary, in a high-temperature environment, the polymer shrinks to expose electrically active sites and increases the background current. Dopamine can normally carry out redox reactions and generate response currents, indicating the “ON” state. In addition, the sensor has a wide detection range (from 0.5 μM to 150 μM) and low LOD (193 nM). This switch-type sensor provides new avenues for the application of thermosensitive polymers.

The current synthesis methods of high-entropy alloy (HEA) thin-film coatings face huge challenges in facile preparation, precise thickness control, conformal integration, and affordability. These challenges are more specific and noteworthy for noble metal-based HEA thin films where the conventional sputtering methods encounter thickness control and high-cost issues (high-purity noble metal targets required). Herein, for the first time, we report a facile and controllable synthesis process of quinary HEA coatings consisting of noble metals (Rh, Ru, Pt, Pd, and Ir), by sequential atomic layer deposition (ALD) coupled with electrical Joule heating for post-alloying. Furthermore, the resulting quinary HEA thin film with a thickness of ∼50 nm and an atomic ratio of 20:15:21:18:27 shows promising potential as a platform for catalysis, exhibiting enhanced electrocatalytic hydrogen evolution reaction (HER) performances with lower overpotentials (e.g., from 85 to 58 mV in 0.5 M H2SO4) and higher stability (by retaining more than 92% of the initial current after 20 h with a current density of 10 mA/cm2 in 0.5 M H2SO4) than other noble metal-based structure counterparts in this work. The enhanced material properties and device performances are attributed to the efficient electron transfer of HEA with the increased number of active sites. This work not only presents RhRuPtPdIr HEA thin films as promising HER catalysts but also sheds light on controllable fabrication of conformal HEA-coated complex structures toward a broad range of applications. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) This work wassupported by the Agency for Science, Technology and Research (A*STAR) AME Individual Research Grant (IRG) A1983c0032. K.W.T. and L.W. acknowledge financial support from the Singapore Ministry of Education AcRF Tier 2 grant (MOET2EP 50221-0017).

Background. IQGAP3 has important function in cancer progression and has become a potential therapeutic target as a transmembrane protein. But its role in tumor immunity and pan-cancer was not systematically investigated. This study evaluated the potential role of IQGAP3 and clinical significance in pan-cancer through combined multiomics analysis. Methods. From Genotype Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) databases, transcriptomic datasets were first obtained, and from Gene Expression Omnibus (GEO), expression profiling microarray data were acquired and integrated to systematically assess the expression differences and prognostic relevance of IQGAP3 in pancreatic cancer. Immunohistochemical data were obtained from Human Protein Atlas (HPA) to assess IQGAP3 protein expression differences, and exome data from TCGA were used to analyze IQGAP3 expression in relation to tumor mutational burden (TMB), microsatellite instability (MSI), and mutation. Additionally, we also analyzed the relationship between IQGAP3 expression and immune checkpoints, mismatch repair (MMR), and IQGAP3 relationship with methylation and copy number variation based on expression profiles. Results. Microsatellite instability (MSI), immune checkpoints, mismatch repair (MMR), and tumor mutational burden (TMB) all closely interacted with IQGAP3 mRNA. In addition, detailed relationships between the immune microenvironment and IQGAP3 mRNA as well as immune cell CD4+ Th2 and myeloid-derived suppressor cells (MDSCs) were determined. Mechanistically, IQGAP3 was involved in cytoskeleton formation, T cell receptor signaling pathways, DNA damage, cell cycle, P53 pathway, Fc gamma R-mediated phagocytosis, and apoptosis. Conclusion. IQGAP3 could serve as an effective prognostic biomarker for pan-cancer immune-related therapy.

The efficiency of hydrogen gas generation via electrochemical water splitting has been mostly limited by the availability of electrocatalyst materials that require lower overpotentials during the redox reaction. Noble metals have been used extensively as electrocatalysts due to their high activity and low overpotentials. However, the use of single noble metal electrocatalyst is limited due to atomic aggregation caused by its inherent high surface energy, which results in poor structural stability, and, hence, poor electrocatalytic performance and long-term stability. In addition, using noble metals as electrocatalysts also causes the cost to be unnecessarily high. These limitations in noble metal electrocatalysts could be enhanced by combining two noble metals in a core-shell structure (e.g., Rh@Ir) as a thin film over a base substrate. This could significantly enhance electrocatalytic activity due to the following: (1) the modification of the electronic structure, which increases electrical conductivity; (2) the optimization of the adsorption energy; and (3) the introduction of new active sites in the core-shell noble metal structure. The current state-of-the-art employs physical vapor deposition (PVD) or other deposition techniques to fabricate core-shell noble metals on flat 2D substrates. This method does not allow 3D substrates with high surface areas to be used. In the present work, atomic layer deposition (ALD) was used to fabricate nanoparticle thin films of Rh@Ir and Rh@Pt in a core-shell structure on glassy carbon electrodes. ALD enables the fabrication of nanoparticle thin film on three-dimensional substrates (a 2D functional film on a 3D substrate), resulting in a significantly increased surface area for a catalytic reaction to take place; hence, improving the performance of electrocatalysis. The Rh@Pt (with an overpotential of 139 mV and a Tafel slope of 84.8 mV/dec) and Rh@Ir (with an overpotential of 169 mV and a Tafel slope of 112 mV/dec) core-shell electrocatalyst exhibited a better electrocatalytic performances compared to the single metal Rh electrocatalyst (with an overpotential of 300 mV and a Tafel slope of 190 mV/dec). These represented a 54% and a 44% improvement in performance, respectively, illustrating the advantages of core-shell thin film nanostructures in enhancing the catalytic performance of an electrocatalyst. Both electrocatalysts also exhibited good long-term stability in the harsh acidic electrolyte conditions when subjected to chronopotentiometry studies. Agency for Science, Technology and Research (A*STAR) Published version This research is supported by the Agency for Science, Technology, and Research (A*STAR) under A*STAR Project No: A1983c0032.

Noble metal medium entropy alloy (MEA) thin films have recently attracted enormous research interests recently because of their great potential in the catalytic application. However, conventional bottom-up fabrication methods for MEA thin film such as magnetron sputtering face enormous challenges including precise control over film thickness and consumption of costly high-purity noble metal targets. Herein, a facile and tunable approach is developed coupling sequential atomic layer deposition (ALD) of noble metal layers with electric Joule heating (EJH) alloying process to grow platinum-iridium-palladium (PtIrPd) MEA thin films. The PtIrPd MEA thin film with a thickness of ≈20 nm and an atomic ratio of 35:35:30 is successfully fabricated. The effect of EJH processing temperature on the film morphology and structure evolution is investigated. ALD provides flexibility in the metal deposition sequence with meticulous thickness control and atomic composition precision, while the ultrafast EJH ramping/cooling rates promote homogeneous alloying of MEA combinations inhibiting phase separation. Furthermore, the integrated method circumvents a major obstacle of finding a common ALD temperature window for different noble metal precursors as well as opens new pathways for the controllable synthesis of multicomponent metal alloy thin films with potential catalytic, magnetic, and optical properties. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Submitted/Accepted version Y.Z. and L.J. contributed equally to this work. The authors acknowledge the funding supported by the Agency for Science, Technology and Research (A*STAR), AME Individual Research Grant (IRG) A1983c0032. K.W.T. and L.W. acknowledges funding support from the Singapore Ministry of Education AcRF Tier 2 grant (MOET2EP 50221-0017).