Plasmon Resonance Research Articles

Lab-on-Fiber Operando Deciphering of a MOF Electrocatalyst.

Despite the great success in deploying metal-organic frameworks (MOFs) as efficient electrocatalysts, the low adoption of operando methods hinders the understanding of underlying mechanism. By leveraging the subtle refractive index evolution, including both the real and the imaginary parts, an entirely new concept of a lab-on-fiber operando method and its feasibility for "pristine-immersion-operando-post analysis" of electrocatalyts are demonstrated. Concurrent collection of absorption spectra and surface plasmon resonance is achieved by engineering fiber-optic waveguidesto simultaneously induce guided light attenuation and plasmonic coupling. In situ-formed Co hydroxide and oxide reactive intermediates in zeolitic imidazolate framework-67 (ZIF-67) electrocatalyst are optically identified, whichshows its underlying self-reconstruction conversions at different stages during electrocatalytic oxygen evolution reactions, and address the gap in knowledge concerning whether ZIF-67 is a precatalyst for real catalyst production. This illuminating operando method offers intriguing opportunities to collect all the observables in a single fiber, provides an exciting potential of a new class of device with long-sought integration and miniaturization capability, and is expected to enable the electrocatalysis community to conquer challenges with conducting multimodal operando experiments outside the laboratory.

Thermoelectric Nanoheterojunction-Mediated Multiple Energy Conversion for Enhanced Cancer Therapy.

Electron-hole recombination and exogenous local hypoxia both impede the effectiveness of thermoelectric tumor catalytic therapy. Here, a thermoelectric heterojunction (Pt-TiO2-x/Ti3C2Tx-PEG) was developed to enhance charge carrier separation and alleviate tumor hypoxia. By incorporating titanium oxide with oxygen vacancies and platinum single atoms onto Ti3C2Tx MXene, we not only improve the charge separation efficiency but also prevent the recombination of positive and negative charges generated by the thermoelectric effect, leading to an increased production of reactive oxygen species (ROS). Furthermore, the Pt SAs exhibited excellent catalase-mimicking (CAT-mimicking) activity, catalyzing hydrogen peroxide to generate oxygen and alleviating the hypoxic tumor microenvironment. Titanium oxide with oxygen vacancies also serves as a sonosensitizer for sonodynamic therapy (SDT), enhancing ROS generation in collaboration with thermoelectric catalytic therapy. Moreover, the photothermal conversion efficiency of Pt-TiO2-x/Ti3C2Tx-PEG is augmented by Pt SAs with a surface plasmon resonance effect, further boosting CAT-mimicking activity and thermoelectric catalytic therapy efficacy. This tumor-specific thermoelectric heterojunction integrates thermoelectric therapy, SDT, and photothermal therapy, demonstrating excellent tumor suppression efficacy both in vitro and in vivo. Therefore, this study offers highly valuable and promising insights into utilizing photothermoelectric/ultrasound-mediated methods for cancer treatment.

Interfacial cfDNA Enrichment and Amplification with On-Chip Thermoplasmonics for Highly Sensitive Cancerous Liquid Biopsy.

Tumor-derived cell-free DNA (cfDNA) has been exploited as an effective liquid biopsy biomarker for early cancer diagnosis. However, the fragmented and low-abundance nature in circulating blood pose challenges for highly sensitive cfDNA quantification. Herein, a multifunctional plasmonic biosensor termed Interfacial cfDNA Enrichment, Amplification and Sensing with on-chip Thermoplasmonics (INEAST) is developed for cfDNA-based liquid biopsy and lung cancer diagnosis. The INEAST biosensor achieved in situ thermoregulation and label-free cfDNA biosensing by simultaneously harnessing interfacial thermoplasmonics and localized surface plasmon resonance. Typical cfDNA biomarkers, including epidermal growth factor receptor (EGFR), tumor protein 53 (TP53), phosphatase and tensin homologue deleted on chromosome 10 (PTEN), and cyclin-dependent kinase inhibitor (CDKN2A), are quantified with detection limits down to femtomolar-level. Through further validation using blood samples from lung cancer patients, the proposed INEAST bioassays demonstrated superior reliability for lung cancer screening, particularly when combined with clinically available tumor-protein metrics. This study demonstrated that the INEAST biosensor enables rapid and sensitive cfDNA quantification, yielding a promising and compatible liquid biopsy for early-stage lung cancer diagnosis.

Green Synthesis of Noble Metal Nanoparticles: Nonlinear Optics and Applications

This study presents a green method for synthesising gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) employing Gum Arabic extract as a reducing and stabilising agent. The synthesised nanoparticles are characterised using UV-Vis absorption spectroscopy and transmission electron microscopy (TEM). The visible colour change and the presence of surface plasmon resonance (SPR) peaks confirmed the formation of silver and gold nanoparticles. The size of the nanoparticles was determined from the UV-Vis spectra data, and the results were compared to sizes measured by TEM. The nonlinear refraction (n2) and nonlinear absorption (b) coefficient of AgNPs and AuNPs at 488 and 514 nm were investigated under continuous wave (CW) mode excitation using the Z-scan technique. By fitting the experimental data to the Z-scan theoretical equations, the nonlinear refraction index and the nonlinear absorption coefficient were found. The origin of the nonlinearities was discussed, and it was proposed to be of thermal effect for the nonlinear refractive index and Reverse Saturation Absorption (RSA) for nonlinear absorption. Optical limiting and switching were demonstrated by taking advantage of the samples' nonlinear optical characteristics.

A Listeria monocytogenes aptasensor on laser inscribed graphene for food safety monitoring in hydroponic water

AbstractConsumption of fresh produce, such as leafy greens, is often encouraged as part of a healthy diet. Hence, indoor facilities for hydroponic production of leafy greens are increasingly being established. However, fresh produce entails a higher risk of microbial foodborne illnesses than processed foods. Listeria monocytogenes is a major source of fresh produce contamination and is among the leading causes of severe foodborne illnesses in the United States, with a 16% mortality rate. Tools for rapid monitoring are needed for pathogens such as L. monocytogenes to prevent outbreaks. In this manuscript, we have demonstrated the feasibility of a multi-aptamer approach for development of label-free aptasensors targeting L. monocytogenes in irrigation water for lettuce hydroponic production. We use screening studies with surface plasmon resonance to rationally develop mixtures of relevant aptamers for targeting L. monocytogenes. Based on this screening, multiple aptamers targeting extracellular structures on intact L. monocytogenes were tethered to platinum-modified laser inscribed graphene electrodes. This is the first report of a L. monocytogenes biosensor based on laser inscribed graphene. We show that mixing multiple aptamers with varying affinity improves the diagnostic performance over one aptamer alone in complex sample matrices (lettuce hydroponic water). Multi-aptamer biosensors showed high accuracy for L. monocytogenes and were at least three times more selective than Escherichia coli (Crooks, K12, O157:H7) with an accuracy of 85%. The limit of detection (10 CFU/10 mL) is based on data which were significantly different after calibration toward L. monocytogenes or E. coli (Crooks) and validated against gold standard molecular analysis (polymerase chain reaction). Rapid screening of pathogens is a global need to meet food safety and water quality regulations. This study shows the importance of sensors targeting more than one bacterial surface structure in complex samples relevant to the food-water nexus.

Biosynthesis of Palladium Nanoparticles by Using Aqueous Bark Extract of Quercus dalechampii, Q. frainetto, and Q. petraea for Potential Antioxidant and Antimicrobial Applications

This study aimed to synthesize palladium nanoparticles (PdNPs) using bioactive compounds from aqueous extracts of Quercus species (Quercus dalechampii, Quercus frainetto, and Quercus petraea) with potential biomedical applications. To optimize PdNPs biosynthesis, various parameters were explored, including the concentration of PdCl2, the extract-to-PdCl2 ratio, and the pH of the solution. The nanoparticles were characterized using ultraviolet/visible spectroscopy (UV/Vis), Fourier-transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS). Total polyphenol content was measured using the Folin–Ciocâlteu method, while antioxidant capacity was evaluated through radical neutralization assays, including ABTS and DPPH, and through iron and copper reduction tests. Antimicrobial activity was tested against Gram-positive and Gram-negative bacteria, as well as Candida species. Phenolic compounds and flavonoids from the extracts were essential for the reduction in palladium ions and the stabilization of the nanoparticles. UV/Vis spectroscopy showed a distinct surface plasmon resonance peak, indicating the successful formation of PdNPs. FTIR analysis confirmed the interaction between the bioactive compounds and PdNPs, revealing characteristic peaks of phenolic groups. DLS analysis indicated a hydrodynamic diameter of 63.9 nm for QD-PdNPs, 48 nm for QF-PdNPs, and 63.1 nm for QP-PdNPs, highlighting good dispersion and stability in solution. Although the PdNPs did not exhibit strong antioxidant properties, they demonstrated selective antimicrobial activity, especially against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA). PdNPs also exhibited significant antifungal activity against Candida krusei, with a minimum inhibitory concentration (MIC) of 0.63 mg/mL, indicating their ability to compromise fungal cell integrity. This study contributes to developing eco-friendly biosynthesis methods for metallic nanoparticles and underscores the potential of PdNPs in various applications, including in the biomedical field.

Probing electronic-structure pH-dependency of Au nanoparticles through X-ray Absorption Spectroscopy

Research on gold nanoparticles (Au NPs) remains a field of intense activity due to their broad range of applications in diverse fields like catalysis, renewable energy, environmental science, and medicine. Herein, the morphological and electronic structures investigation of Au NPs prepared at different pH values is reported. The dependence of the localized surface plasmon resonance wavelength and electronic structure with size was determined by combining transmission electron microscopy, and various spectroscopic methods led by X-ray absorption spectroscopy. The X-ray absorption experiments evidenced that the citrate-stabilized Au NPs bulk electronic structure remains intact over a broad range of pHs, and changes were detected resulting from differences in NPs surface terminations.

Design and Optimization of Graphene-Based Ultra-Wideband Surface Plasmon Resonance Solar Absorber Using Machine Learning

Design and Optimization of Graphene-Based Ultra-Wideband Surface Plasmon Resonance Solar Absorber Using Machine Learning

Leaf-Shaped Nanostrip Fed Graphene Plasmonic Nano-Antenna for Optical Near-Field Applications

The manuscript investigates the leaf-shaped nanostrip-fed graphene plasmonic nanopatch on a silicon dioxide surface for optical near-field applications. The dispersion properties of graphene and silicon dioxide are demonstrated through Drude and Lorentz modeling to examine the suitability of the materials for the plasmonic nano-antenna design. The nano-antenna parameters TSUB (substrate thickness), W (width of the nanostrip feed line) and RL(nano-antenna size) are adjusted to modify the plasmonic resonance frequency from 7.9 THz to 40.9 THz. The proposed leaf-shaped nanostrip-fed graphene plasmonic nanopatch exhibits a reflection of -43.27 dB at 36 THz with a gain of 8.19 dB at TSUB =125 nm, W = 40 nm and RL = 50 nm.

Advanced PROTAC and Quantitative Proteomics Strategy Reveals Bax Inhibitor-1 as a Critical Target of Icaritin in Burkitt Lymphoma

Understanding the molecular targets of natural products is crucial for elucidating their mechanisms of action, mitigating toxicity, and uncovering potential therapeutic pathways. Icaritin (ICT), a bioactive flavonoid, demonstrates significant anti-tumor activity but lacks defined molecular targets. This study employs an advanced strategy integrating proteolysis targeting chimera (PROTAC) technology with quantitative proteomics to identify ICT’s key targets. A library of 22 ICT-based PROTAC derivatives were synthesized, among which LJ-41 exhibited a superior IC50 of 5.52 μM against Burkitt lymphoma (CA-46) cells. Then, differential proteomic analysis identified Bax inhibitor-1 (BI-1) as a potential target. Target validation techniques, including cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS) assay, surface plasmon resonance (SPR) assay, and molecular docking, confirmed LJ-41’s high specificity for BI-1. Mechanistic investigations revealed that LJ-41 induces apoptosis through BI-1 degradation, triggering endoplasmic reticulum stress and activating inositol-requiring enzyme 1 α (IRE1α), activating transcription factor 6 (ATF6), and nuclear factor erythroid 2-related factor transcription factor heme oxygenase 1 (NRF2-HO-1) signaling pathways. This study establishes a refined methodological framework for natural product target discovery and highlights ICT-PROTAC derivatives’ potential for clinical application in Burkitt lymphoma treatment.

Salivary gland protective and antiinflammatory effects of genistein in Sjögren’s syndrome by inhibiting Xist/ACSL4-mediated ferroptosis following binding to estrogen receptor-alpha

BackgroundSjögren’s syndrome (SS) is an autoimmune disease with limited effective treatment options. This study aimed to explore the underlying mechanism by which genistein–estrogen receptor alpha (ERα) complex targets X-inactive specific transcript (Xist) then leads to the inhibition of ferroptosis by regulating acyl-CoA synthetase long-chain family member 4 (ACSL4) expression in salivary gland epithelial cells (SGECs) to attenuate SS.MethodsThe effects of genistein treatment on the progression and underlying mechanism of SS were investigated using nondiabetic obese (NOD)/LtJ mice in vivo and Interferon-γ (IFNγ)-treated SGECs in vitro. Water intake and saliva flow rate were measured to evaluate the severity of xerostomia. Hematoxylin–eosin staining, real-time quantitative polymerase chain reaction, and enzyme-linked immunosorbent assay were conducted to examine the pathological lesions. Western blotting and immunohistochemistry analysis were used to evaluate the protein expression. RNA sequencing and RNA fluorescence in situ hybridization were employed to verify the relationship between Xist and ACSL4. Surface plasmon resonance, molecular docking, and molecular dynamics were used to investigate the binding between genistein and ERα. Furthermore, a chromatin immunoprecipitation assay was used to analyze ERα–XIST promoter interactions. The levels of malondialdehyde, glutathione, Fe2+, and mitochondrial changes were measured to evaluate ferroptosis of SGECs.ResultsIn NOD/LtJ mice, a ferroptosis phenotype was observed in salivary glands, characterized by downregulated Xist and upregulated X chromosome inactivation gene Acsl4. Genistein significantly alleviated SS symptoms, upregulated the Xist gene, and downregulated Acsl4 expression. Genistein upregulated Xist expression in the salivary gland of NOD/LtJ mice via the ERα signaling pathway. It downregulated Acsl4 and ferroptosis in the salivary glands of NOD/LtJ mice. IFNγ-treatment induced inflammation and ferroptosis in SGECs. Genistein binding to ERα upregulated XIST, and aquaporin 5 expression, downregulated ACSL4, and SS antigen B expression, and reversed ferroptosis in SGECs. Genistein mitigated inflammation and ferroptosis in SGECs by upregulated-XIST-mediated ACSL4 gene silencing.ConclusionsGenistein binding to ERα targets Xist, leading to inhibiting ferroptosis by regulating ACSL4 expression in SGECs. This finding provides evidence for genistein as a treatment for SS and identifies Xist as a novel drug target for SS drug development, offering great promise for improving SS outcomes.Graphical

Ultralow limit human IgG detection with 2H-MoS2/L-cysteine based plasmonic fiber-optic spectral combs

The detection of human immunoglobulin G (human IgG) provides crucial evidence in diagnosis of infectious diseases and monitoring of therapeutic effects. Here, we propose a plasmonic fiber-optical surface plasmon resonance (SPR) based sensor to realize the ultralow limit human IgG detection. The proposed sensor is fabricated by attaching a mixture of 2H-MoS2 nanosheets with L-cysteine on a gold-coated tilted fiber Bragg grating. The 2H-MoS2 possesses a large specific surface area, where the L-cysteine can enhance the stability of antibody modification. The composite membrane of 2H-MoS2 and L-cysteine can adsorb more probe rabbit anti-human IgG, which can improve sensitivity of the proposed sensor. The experimental results show that the proposed sensor exhibits a response time of approximately 220 s and a sensitivity of 0.11 dB/(ng/ml). The limit of detection of 0.87 ng/ml of the proposed sensor is one order of magnitude lower than those of other fiber-optic SPR human IgG sensors.

Phytochemical Analysis, Isolation, and Characterization of Gentiopicroside from Gentiana kurroo and Cytotoxicity of Biosynthesized Silver Nanoparticles Against HeLa Cells.

Gentiana kurroo Royle, a critically endangered Himalayan herb, is valued in treating leucoderma, syphilis, bronchial asthma, hepatitis, etc. The current investigation performed quantitative and qualitative phytochemical analysis of G. kurroo root extracts prepared in chloroform, methanol, and ethyl acetate. The phenolic and flavonoid contents were the highest in methanol and chloroform extract, respectively. Several pharmacologically important compounds were identified through gas chromatography-mass spectrometry. Antioxidant analysis revealed methanolic extract to be the most efficient scavenger of 2,2-diphenyl-1-picrylhydrazyl (IC50 = 114µgmL-1), hydrogen peroxide (IC50 = 109.9µgmL-1), and superoxide (IC50 = 74.63µgmL-1) radicals. Gentiopicroside was isolated from the methanolic root extract through silica-gel column-chromatography, and the characterization of concentrated fractions was achieved employing various analytical techniques. Pertaining to silver nanoparticle (GkAgNPs) synthesis, different physicochemical parameters were optimized and it was observed that root extract treated with silver-nitrate (0.5mM) at 60°C and incubated in dark for at least 120min after initial color change, yielded GkAgNPs optimally. GkAgNPs were anisotropic and polydisperse and exhibited characteristic surface plasmon resonance (424nm), crystalline face-centered cubic geometry, size (50-300nm), and zeta-potential (- 16.3mV). FT-IR spectra indicated the involvement of phenols and flavonoids in AgNPs synthesis. GkAgNPs were evidenced as strongly cytotoxic (IC50 = 1.964µgmL-1) against HeLa cells and also showed deformed cellular morphology, a significant reduction in viable cell counts and colony-forming efficiency (4.08%). The findings suggest potential applications in drug development for treating serious human diseases. To the best of our knowledge, this study represents the first report on the isolation of gentiopicroside, the bio-fabrication of GkAgNPs using G.kurroo root extract, and their strong bioefficacy against HeLa cells.

Exploring the Molecular Mechanism of Niuxi-Mugua Formula in Treating Coronavirus Disease 2019 via Network Pharmacology, Computational Biology, and Surface Plasmon Resonance Verification.

In China, Niuxi-Mugua formula (NMF) has been widely used to prevent and treat coronavirus disease 2019 (COVID-19). However, the mechanism of NMF for treating COVID-19 is not yet fully understood. This study aimed to explore the potential mechanism of NMF for treating COVID- 19 by network pharmacology, computational biology, and surface plasmon resonance (SPR) verification. The NMF-compound-target network was constructed to screen the key compounds, and the Molecular Complex Detection (MCODE) tool was used to screen the preliminary key genes. The overlapped genes (OGEs) and the preliminary key genes were further analyzed by enrichment analysis. Then, the correlation analysis of immune signatures and the preliminary key genes was performed. Molecular docking and molecular dynamic (MD) simulation assays were applied to clarify the interactions between key compounds and key genes. Moreover, the SPR interaction experiment was used for further affinity kinetic verification. Lipid and atherosclerosis, TNF, IL-17, and NF-kappa B signaling pathways were the main pathways of NMF in the treatment of COVID-19. There was a positive correlation between almost the majority of immune signatures and all preliminary key genes. The key compounds and the key genes were screened out, and they were involved in the main pathways of NMF for treating COVID-19. Moreover, the binding affinities of most key compounds binding to key genes were good, and IL1B-Quercetin had the best binding stability. SPR analysis further demonstrated that IL1B-Quercetin showed good binding affinity. Our findings provided theoretical grounds for NMF in the treatment of COVID-19.

Improved absorption of phosphates through interface junctions and photothermal–energy–storage capability of Ca(OH)2–[Co3O4–Co3(PO4)2]

Strong absorption in the full solar spectrum is required for efficient usage of solar energy. Near-infrared (NIR) light absorption mainly depends on surface plasmon resonance and a high density of free charge carriers (FCCs). However, increasing FCC density in semiconductors is still a challenge. In this work, we demonstrated that multitudinous S-scheme interface junctions can be constructed within nanoscale Co3O4–Co3(PO4)2, leading to enhanced light absorption of phosphates over the entire solar spectrum due to the increased FCC density and charge-carrier configurations. This absorber can also boost the photothermal performance of Ca(OH)2. The photothermal dehydration conversion of Ca(OH)2 is considerably improved (13.7 times). The reversibility of the photothermal hydration–dehydration cycles of Ca(OH)2 is improved by 39 times. This composite is promising for photothermal conversion and thermal energy storage in one-step.

Diosmin reduces the stability of Snail and Cyclin D1 by targeting FAK to inhibit NSCLC progression

BackgroundIn different tumours, focal adhesion kinase (FAK), a nonreceptor tyrosine kinase, is upregulated and hence, it represents a promising target for cancer therapy. However, the development of FAK kinase inhibitors has faced a number of challenges. It is therefore imperative that new, effective FAK kinase inhibitors be identified promptly. MethodsSmall molecules that target FAK were identified through molecular docking and validated through surface plasmon resonance (SPR) and cell thermal shift analysis. We investigated the pharmacological effects of FAK kinase inhibitors using CCK-8, colony formation, EdU, and Transwell assays and cell cycle analysis. The molecular mechanism was determined via methods such as coimmunoprecipitation, RNA pull-down and RNA immunoprecipitation. ResultsHere, we confirmed that diosmin (Dio) is an inhibitor of FAK and demonstrated its anti-proliferative and anti-metastatic effects in lung adenocarcinoma. Mechanistically, Dio inhibited tumour proliferation and metastasis by impeding the catalytic activity of FAK. Dio activated the ubiquitin proteasome pathway to induce Cyclin D1 degradation, while inhibiting tumour proliferation and reversing the epithelial mesenchymal transition (EMT) process by reducing the mRNA stability of Snail, thereby inhibiting cancer metastasis. In addition, the inhibitory effect of Dio on lung adenocarcinoma was validated in a mouse xenograft model. ConclusionThese results support the tumour-promoting role of FAK in lung adenocarcinoma by stabilizing Cyclin D1 and Snail and suggest that Dio is a promising candidate for FAK inhibition.

Removal of tetracycline using an ultrastable Pt-decorated-BNCB photocatalyst under efficient solar-driven conditions

The pursuit of optimizing the photocatalytic performance of the novel perovskite-like Bi4NbO8X materials remains a vibrant area of research. In this paper, we report the successful synthesis of the Bi4Nb4O8Cl0.935Br0.065 (BNCB) composite photocatalyst, loaded with Pt nanoparticles, utilizing a combination of solid-state reaction and sodium borohydride reduction methods. Notably, the surface plasmon resonance (SPR) effect exhibited by Pt broadened the spectral response range, while the Schottky junction formed at the Pt/BNCB interface significantly accelerated the separation of photogenerated electron-hole pairs and facilitated the swift migration of photogenerated electrons towards Pt. Experimental outcomes underscore the superior photocatalytic degradation efficacy of the Pt/BNCB composite towards tetracycline (TC), achieving a degradation rate of up to 67%, significantly outperforming pure BNCB. Pt/BNCB exhibits excellent photocatalytic degradation and excellent stability in various pH and ionic environments. Collectively, this work presents a novel approach for designing highly efficient and stable perovskite-type photocatalytic materials, holding immense potential for applications in environmental remediation.

CEA-Induced PI3K/AKT Pathway Activation through the Binding of CEA to KRT1 Contributes to Oxaliplatin Resistance in Gastric Cancer

BackgroundThe serum level of carcinoembryonic antigen (CEA) has prognostic value in patients with gastric cancer (GC) receiving oxaliplatin-based chemotherapy. As the molecular functions of CEA are increasingly uncovered, its role in regulating oxaliplatin resistance in GC attracts attention. MethodsThe survival analysis adopted the KaplanMeier method. Effects of CEA on proliferative capacity were investigated using CCK8, colony formation, and xenograft assays. Oxaliplatin sensitivity was identified through IC50 detection, apoptosis analysis, comet assay, organoid culture model, and xenograft assay. Multi-omics approaches were utilized to explore CEA’s downstream effects. The binding of CEA to KRT1 was confirmed through proteomic analysis and Co-IP, GST pull-down, and immunofluorescence colocalization assays. Furthermore, small molecule inhibitors were identified using virtual screening and surface plasmon resonance. ResultsStarting from clinical data, we confirmed that CEA demonstrated superior ability to predict the prognosis of patients with GC who received oxaliplatin-based chemotherapy, particularly in predicting recurrence-free survival based on serum CEA level. In vitro and in vivo experiments revealed CEAhigh GC cells presented increased proliferative capacity and decreased oxaliplatin sensitivity. The resistance phenotype was transmitted through secreted CEA. Multi-omics analysis revealed that CEA activated the PI3K/AKT pathway by binding to KRT1, leading to oxaliplatin resistance. Finally, the small molecule inhibitor evacetrapib, which competitively inhibits the CEA-KRT1 interaction, was identified and validated in vitro. ConclusionsIn summary, the CEA-KRT1-PI3K/AKT axis regulates oxaliplatin sensitivity in GC cells. Treatment with small molecule inhibitors such as evacetrapib to inhibit this interaction constitutes a novel therapeutic strategy.

Surface Plasmon Resonance Sensor with 2D Materials for Enhanced Refractive Index Detection of Chemical Pollutants in Seawater

This paper introduces a highly sensitive, graphene-based, multilayer surface plasmon resonance (SPR) refractive index sensor is designed for the detection of chemical pollutants in seawater. The sensor structure consists of multiple layers, specifically BK7 glass, Chromium (Cr), Copper (Cu), MXene, and Graphene. SPR sensors have gained significant attention in the field of real-time chemical sensing due to their label-free detection capabilities, high sensitivity, and excellent reproducibility. In this sensor design, the refractive index (RI) of the sensing region is altered by the interaction of chemical pollutants present in the seawater. These variations in RI directly affect the excitation of surface plasmon polaritons (SPPs) at the multilayer sensor interface. This interaction forms the basis for detecting chemical pollutants, as changes in RI modulate the sensor's optical response, which can be accurately measured. The performance of the proposed sensor is thoroughly evaluated using numerical simulations based on the Transfer Matrix Method (TMM). The simulations are carried out over a refractive index range of 1.329 to 1.433, covering the typical RI variations caused by chemical pollutants in seawater. The sensor demonstrated exceptional performance, achieving a maximum sensitivity of 186deg/RIU at an operational wavelength of 633nm. Additionally, the sensor is exhibited a high detection accuracy (DA) of 1.5deg⁻¹ and a figure of merit (FOM) of 205 RIU⁻¹, highlighting its ability to precisely distinguish small changes in refractive index. These results emphasize the potential of this graphene-based SPR sensor configuration for high-performance detection of chemical pollutants, making it an excellent candidate for environmental monitoring applications. Its robust design, combined with its high sensitivity and accuracy, positions it as a promising solution for addressing challenges in seawater pollution detection and monitoring.

Dual-channel SPR sensor based on an MMF-DHSMF-NCF reflective structure

This manuscript introduces a novel dual-channel surface plasmon resonance (SPR) sensor, employing a reflective configuration comprising fused multimode fiber (MMF), dual-hole single mode fiber (DHSMF), and no-core fiber (NCF) for refractive index (RI) and temperature detection simultaneously. By exploiting distinct refractive indices outside the fibers, the sensor enables dual-channel SPR functionality: one channel is activated by a gold-covered DHSMF for RI sensing, while the other utilizes a gold and polydimethylsiloxane (PDMS)-coated NCF for temperature monitoring. Experimental results illustrates sensitivities to refractive index and temperature are 4341 nm/RIU and −2.63 nm/℃, respectively. With its compact design, ease of installation, and robust stability, the sensor is well-suited for concurrent RI and temperature detection.