Metal Nanoparticles Research Articles

Comparative evaluation of flexural strength of conventional heat polymerized denture base resin reinforced with non-silanized and silanized aluminum oxide powder- An in vitro study

Although denture base acrylic resins have been used since many decades, the problem of facture of denture base still remains. Many researchers have tried to reinforce the denture base by addition of metallic oxide nanoparticles. Silanization of such nanoparticles is recommended as it improves the bond between fillers and added nanoparticles. To evaluate and compare the flexural strength (FS) of heat polymerized acrylic resin denture base material reinforced with 2.5 wt % of non-silanized and silanized aluminum oxide powder (AlO). : Seventy-five specimens of heat polymerized acrylic resin were fabricated. The specimens were divided into three groups (n = 75) coded as Group N (non-silanized AlO), Group S (silanized AlO) and Group C (Control). The specimens of the remaining two groups were reinforced with 2.5 wt % of non-silanized and silanized AlO. The flexural strength of the specimens was measured using 3-point bending test in a Universal Testing Machine. Data analyses using analysis of variance and Tukey’s post-hoc test showed that adding 2.5 wt% of silanized AlO; GroupS significantly increased the flexural strength compared to Group C and GroupN (p<0.0001). Within the limitation of this study, AlO fillers are potential reinforcers in denture bases which increased flexural strength.

Synthesis, characterization, and CO2methanation over hierarchical ZSM-5-NiCoAl layered double hydroxide nanocomposites:Improvement of C-C coupling to ethane.

To date, preparing materials with highly dispersed metal nanoparticles without metal agglomeration on a solid support is challenging. This work presents an alternative approach for synthesizing NiCo species on hierarchical ZSM-5 materials derived from a core-shell ZSM-5@NiCoAl-LDHs composite. The designed material was prepared by the growth of a NiCo-LDHsprecursor on the surface of hierarchical ZSM-5 nanosheets. The effect of the weight ratio of NiCo-LDHs precursor to ZSM-5 on the composite properties has been studied. The results show that 45 wt.% LDHs is the most suitable condition for preparing NiCoAl-LDHs/ZSM-5 composite with a core-shell structure, which promotes a strong interaction between bimetallic NiCo and hierarchical ZSM-5. The ZSM-5@NiCoAl-LDHs-45 showed a BET surface of 386 m2.g-1, in which the surface area has been re-allocated between microspores and mesopores due to the presence of NiCoAl-LDHs composite. The catalyst wasalsotested for CO2methanation at 380 °C under atmospheric hydrogen pressure. The results show that the catalyst could provide CO2conversion of up to 40% at WSHV of 2.91 h-1. Interestingly, it could not only promote methane but also provide a high selectivity of ethane, approximately 20.4%. Moreover, the excellent catalytic stability of ethane production was illustrated over 24 hours of time-on-stream.

Bimetallic PdPt nanoparticle-incorporated PEDOT:PSS/guar gum-blended membranes for enhanced CO2 separation.

To address the escalating demand for efficient CO2 separation technologies, we introduce novel membranes utilizing natural polymer guar gum (GG), conjugate polymer (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)) PEDOT:PSS, and bimetallic PdPt nanoparticles. Bimetallic PdPt nanoparticles were synthesized using the wet chemical method and characterized using X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) techniques. The morphologies, chemical bonds, functional groups, and mechanical properties of the fabricated membranes were characterized using various techniques. Through meticulous fabrication and characterization, the binary blended membranes demonstrated enhanced homogeneity and smoothness in their structure, attributed to the interaction between the polymers, and superior CO2 permeability due to the amphiphilic nature of the PEDOT:PSS polymer. Gas separation experiments performed using H2, N2, and CO2 gases confirmed that the 20% PEDOT:PSS/GG blended membranes showed the best performance with sufficient mechanical properties. Moreover, the results demonstrated an increase of 172% in CO2 permeability and 138% in CO2/H2 selectivity, respectively. Furthermore, integrating bimetallic PdPt nanoparticles provided an additional 197% increase in CO2/H2 selectivity, owing to the unique catalytic activities of noble metal nanoparticles. The study not only underscores the transformative potential of polymer blending and noble metal engineering, but also highlights the significance of using natural polymers for sustainable environmental solutions.

Metallic nanoparticles for tumor microenvironment modulation

Cancer is a complex, multifaceted disease influenced by genetic predispositions, lifestyle factors such as nutrition, exercise, and toxin exposure, as well as environmental conditions. A key element in cancer initiation, progression, metastasis, and therapeutic response is the tumor microenvironment (TME). Within the TME, immune cells like T cells, B cells, and immunoglobulins have a profound and direct impact on the growth and spread of tumor cells. As a result, effective regulation of the TME has become crucial for successful cancer treatment. Metal nanoparticles (MNPs), ranging from 1 to 100 nanometers, have shown great potential as agents for modulating the TME, delivering drugs, and improving cancer diagnostics. This discussion explores both the internal and external components of the TME, focusing on how MNPs influence the microenvironment. We highlight their targeting mechanisms and interactions with immune responses and tumor-associated inflammation. Due to their unique properties, MNPs offer distinct advantages in cancer therapy, and their range of applications continues to expand. This review underscores the potential of MNPs as a promising material in the future of cancer treatment.

Chemical Synthesis of ~1 nm Multilevel Capacitor‐like Particles with Atomic Precision

AbstractCan the chemically synthesized nanoparticles act as nanodevices or nanomachines? Herein, we demonstrated this feasibility. A novel nanocluster (ultrasmall nanoparticle) [Au44Cd20(m‐MBT)40][N(C8H17)4]2 (Au44Cd20 in short, m‐MBTH: m‐methylbenzenethiol) obtained via developing a synthesis method has a cannula‐like structure of the outer shell and an internal sleeve, revealed by single‐crystal X‐ray diffraction. Natural population analysis (NPA) charge calculations, charge carrier transport of Au44Cd20 (during which an intra‐nanocluster anti‐galvanic reaction was observed) after unneutral charging using NaBH4 as well as voltammetry proved the capacitor‐like character of Au44Cd20. The subsidiary capacitor‐like character of the outer shell of Au44Cd20 was further probed via NPA charge calculations and electrocatalytic reduction of CO2 to CO. Thus, this study predicts a new era of engineering metal nanoparticles for realizing atomically precise ultrasmall nanodevices and nanomachines.

Chemical Synthesis of ~1 nm Multilevel Capacitor-like Particles with Atomic Precision.

Can the chemically synthesized nanoparticles act as nanodevices or nanomachines? Herein, we demonstrated this feasibility. A novel nanocluster (ultrasmall nanoparticle) [Au44Cd20(m-MBT)40][N(C8H17)4]2 (Au44Cd20 in short, m-MBTH: m-methylbenzenethiol) obtained via developing a synthesis method has a cannula-like structure of the outer shell and an internal sleeve, revealed by single-crystal X-ray diffraction. Natural population analysis (NPA) charge calculations, charge carrier transport of Au44Cd20 (during which an intra-nanocluster anti-galvanic reaction was observed) after unneutral charging using NaBH4 as well as voltammetry proved the capacitor-like character of Au44Cd20. The subsidiary capacitor-like character of the outer shell of Au44Cd20 was further probed via NPA charge calculations and electrocatalytic reduction of CO2 to CO. Thus, this study predicts a new era of engineering metal nanoparticles for realizing atomically precise ultrasmall nanodevices and nanomachines.

Gold Nanoparticle Catalyzed Solvent Switchable Selective Partial Reduction of Nitrobenzene to N‐Phenylhydroxylamine and Azoxybenzene

Impregnation of phosphine‐decorated polymer immobilized ionic liquid with the tetrachloroaurate anion results in reduction of the gold(III) to gold(I) with concomitant oxidation of the phosphine to its oxide. In situ reduction of the resulting precursor, AuCl@O=PPh2‐PEG‐PIILS, generated the corresponding O=PPh2‐PEGPIIL‐stabilised AuNPs, AuNP@O=PPh2‐PEGPIILS, which is a highly active and selective catalyst for the solvent dependent partial reduction of nitrobenzene to N‐phenylhydroxylamine in water and azoxybenzene in ethanol. The initial TOFs are comparable to those obtained with gold nanoparticles generated by reduction of tetrachloroaurate‐impregnated phosphine oxide decorated polymer immobilized ionic liquid AuCl4@O=PPh2‐PEGPIILS i.e. the activity and selectivity profiles do not depend on whether the AuNPs are generated from Au(III) or in situ generated Au(I). In stark contrast, gold nanoparticles prepared by NaBH4 reduction of AuCl@PPh2‐PEGPIILS based on gold(I) confined in phosphine modified polymer immobilized ionic liquid gave markedly lower initial TOFs. The use of dimethylamine borane as the hydrogen donor resulted in a substantial enhancement in activity for reductions conducted in water compared with NaBH4 and the initial TOF of 20,400 mole nitrobenzene converted mol Au‑1h‑1 obtained with AuNPs generated in situ from AuCl4@O=PPh2‐PEGPIILS is among the highest to be reported for the metal nanoparticle catalyzed selective reduction of nitrobenzene to N‑phenylhydroxylamine.

Biosynthesis, Characterization, and Antibacterial Activity of Gold, Silver, and Bimetallic Nanoparticles Using Annona squamosa L. Leaves

The utilization of nano-sized drug delivery systems in herbal drug delivery systems has a promising future for improving drug effectiveness and overcoming issues connected with herbal medicine. As a consequence, the use of nanocarriers as novel drug delivery systems for the improvement of traditional medicine is critical to combating infectious diseases globally. In line with this, we herein report the biosynthesis of silver nanoparticles (AgNPs), gold nanoparticles (AuNPs), and bimetallic nanoparticles (BMNPs) as antibacterial agents against pathogenic bacterial strains using Annona squamosa L. leaf extract as a bio-reductant and bio-stabilizing agent. The as-synthesized metal nanoparticles were characterized by transmission electron microscopy (TEM), ultraviolet–visible (UV–Vis) absorption spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and the dynamic light scattering (DLS) method. The as-synthesized MNPs had an average particle size of 6.98 nm ± 2.86 nm (AgNPs), 21.84 ± 8.72 nm (AuNPs), and 2.05 nm ± 0.76 nm (BMNPs). The as-synthesized AgNPs and BMNPs showed good antibacterial activity against pathogenic bacterial strains of Gram-positive Staphylococcus aureus (ATCC 25923) and Gram-negative Escherichia coli (ATCC 25922). The obtained results offer insight into the development of benign nanoparticles as safe antibacterial agents for antibiotic therapy using Annona squamosa L. leaf extract.

Molecular Dynamics & FDTD Methods Synergistic Modulation for Surface Emission in Luminescent Glass by Metal Nanoparticles

Molecular Dynamics & FDTD Methods Synergistic Modulation for Surface Emission in Luminescent Glass by Metal Nanoparticles

The In Vitro Cytotoxic Potential of Biosynthesized Silver Nanoparticles in MIA PaCa-2 Cells Supported with an In Silico Study

Pancreatic cancer affects many people and is quite aggressive. Metallic nanoparticles may be an alternative treatment for this disease. In this work, the antiproliferative activity of biosynthesized silver nanoparticles was evaluated. Stenocereus queretaroensis peel extract was used as a reducing agent for nanoparticle synthesis; the characterization was carried out using spectroscopic techniques, X-ray diffraction, and microscopy. The antiproliferative effect was evaluated in the MIA PaCa-2 pancreatic tumoral cell line, and a molecular docking test was run with the STAT3 protein. The results obtained show that it was possible to synthesize silver nanoparticles from the plant extract, which was confirmed through characterization studies. The average size of the nanoparticles was measured to be 48.8 nm, and they predominantly exhibited a spherical shape. The antiproliferative effect was demonstrated in the pancreatic cell line, with an IC50 value of 15.66 µg/mL. The molecular docking analysis predicted a strong interaction with the STAT3 protein, with a binding energy value of −6.47 obtained. With these results, it is concluded that biosynthesized silver nanoparticles inhibit pancreatic tumor cell growth and may represent an innovative cancer treatment.

Theoretical investigation of structure and electronic properties in Cisplatin-citrate complexes.

Cisplatin (CDDP) is an effective Platinum (Pt) based anticancer drug used in chemotherapy. However, its effectiveness is limited due to its instability in solvents, along with the side effects it causes due to DNA damage. Nanoparticles (NPs) were developed in vitro to address these issues by loading CDDP into various types of NPs, including metal, lipid, and biological NPs. Citrate was employed as a biocompatible compound in nanomedicine to reduce cytotoxicity and enhance stability. In our study, the physicochemical and electronic properties of CDDP and citrate have been investigated using density functional theory (DFT), with a comparison of their behavior in water and DMSO. Additionally, TD-DFT was applied to analyze the UV-Vis spectra results. Six complexes have been proposed to better understand the interaction between citrate and CDDP. The results demonstrated that the CDDP could form stable complexes with citrate in both water and DMSO, and the considered complexes exhibited UV-Vis spectra within the experiment range. The frontier orbitals, electron densities mapping, and electrostatic potential analysis revealed that complex 5, where citrate di-substituted on two chlorides, is the most likely and effective complex. In summary, our investigation sheds light on the potential of CDDP-citrate complexes to address the limitations of CDDP, offering insights into their stability and interaction in solvents and highlighting the promising efficacy of specific complex formations for future therapeutic applications.

Hybrid nanoparticle array fabricated using injection‐molded nanostructure

AbstractNow that well‐ordered nanoparticles can yield a promising performance in various fields, spatially regular arrangement of particles is a key requirement for nanoparticle‐embedded engineering materials and devices. Here, we demonstrate a feasible, robust method where nanoparticles can be regularly distributed and encapsulated. Polymeric substrates with different sized nanoholes were injection‐molded by controlling mold‐wall temperature in a spatial and temporal manner. A hybrid structure of nanoparticles was constructed by binding quantum dots with metal nanoparticles, and they were filled into the nanoholes using the knife coating process. The morphology of the nanostructure prepared via the molding process and the nanoparticle array was analyzed using a scanning electron microscope and a transmission electron microscope. Fluorescence emission of the hybrid nanostructure was measured. The finding showed that the strategic approach introduced in this study could allow fabrication of hybrid nanoparticle structures with good processability and productivity. © 2024 Society of Chemical Industry.

Nanomedicine in the treatment of Alzheimer's disease: bypassing the blood-brain barrier with cutting-edge nanotechnology.

Alzheimer's disease (AD) remains a formidable challenge in the field of neurodegenerative disorders, necessitating innovative therapeutic strategies. Nanomedicine, leveraging nanomaterials, has emerged as a promising avenue for AD treatment, with a key emphasis on overcoming the blood-brain barrier (BBB) to enhance drug delivery efficiency. This review provides a comprehensive analysis of recent advancements in the application of nanomaterials for AD therapy, highlighting their unique properties and functions. The blood-brain barrier, a complex physiological barrier, poses a significant hurdle for traditional drug delivery to the brain. Nanomedicine addresses this challenge by utilizing various nanomaterials such as liposomes, polymeric nanoparticles, and metal nanoparticles. These nanocarriers enable improved drug bioavailability, sustained release, and targeted delivery to specific brain regions affected by AD pathology. The review discusses the diverse range of nanomaterials employed in AD treatment, exploring their capacity to encapsulate therapeutic agents, modulate drug release kinetics, and enhance drug stability. Additionally, the multifunctionality of nanomaterials allows for simultaneous imaging and therapy, facilitating early diagnosis and intervention. Key aspects covered include the interaction of nanomaterials with Aβ aggregates, the role of antioxidants in mitigating oxidative stress, and the potential of nanomedicine in alleviating neuroinflammation associated with AD. Furthermore, the safety, biocompatibility, and toxicity profiles of various nanomaterials are scrutinized to ensure their clinical applicability. In conclusion, this review underscores the pivotal role of nanomedicine and nanomaterials in revolutionizing AD treatment strategies. By specifically addressing BBB challenges, these innovative approaches offer new avenues for targeted drug delivery and improved therapeutic outcomes in the complex landscape of Alzheimer's disease.

Biomimetically Inspired Micro‐Nano Hierarchical Structures of Rose Petals for Efficient SERS Sensing Applications

AbstractSurface‐enhanced Raman spectroscopy (SERS) detection is a crucial technology for rapid sensing and “fingerprinting”, achieved through the combination of Raman spectroscopy and arrays of noble metal nanoparticles (NPs). This study introduces a low‐cost biomimetic‐inspired approach to fabricate rose petal structured micro/nano hierarchical structures with silver (Ag) film, serving as a reliable SERS substrate. These substrates are thoroughly compared by replicating the upper surface of rose petals of different colors into a transparent polydimethylsiloxane (PDMS) mixture and subsequently sputtering Ag film of varying thicknesses. Ultimately, the white negative rose PDMS replica is chosen, demonstrating a high enhancement factor, good batch‐to‐batch reproducibility, high stability, and high sensitivity for crystal violet (CV), an organic contaminant with mutagenic and toxigenic properties. In a proof‐of‐concept experiment, the multiplex detection capability of this SERS substrate is demonstrated by analyzing a combination of two sets of analytes (CV and methylene blue as well as CV and Nile blue A). Furthermore, this SERS substrate is utilized to test tau protein and amyloid β peptides, both recognized biomarkers of Alzheimer's disease. This study illustrates that the proposed 3D SERS substrate exhibits significant potential for the highly sensitive and rapid detection of biomolecules in practical applications.

A Contactless Method for Measuring the Redox Potentials of Metal Nanoparticles.

The standard redox potentials of metal nanoparticles are important for understanding their chemical properties. Traditionally, these redox potentials are measured by using voltammetry. Although voltammetry is fast and cost-effective, loading or landing the nanoparticles on electrodes alters their electrochemical properties, posing a challenge for accurately determining their intrinsic redox potentials. Here, a contactless method was developed utilizing chemical assays and the Nernst equation to measure the standard reduction potentials of gold nanoparticles in their colloidal state. To showcase the versatility and accuracy of this Nernstian approach, the reduction potentials were measured for a size range of 5.0-73 nm, revealing their scaling law and dependence on the nanoparticle surface energy.

Biosintesis Nanopartikel Seng Oksida dengan Ekstrak Limbah Kulit Pisang Tanduk (Musa paradisiaca fa. corniculata)

The high amount of banana consumption in Indonesia has caused banana peel waste to increase, which can cause environmental pollution. One of the utilization of banana peel waste is as a metal nanoparticle synthesis. This study aims to synthesize ZnO nanoparticles with banana peel extract as a capping agent and determine the effect of solvent volume variation on the characterization of ZnO particles using variable volume of ethanol-water solvent with a ratio of 2:1 and 1:1 (v/v). This research uses maceration extraction method for 24 hours. Characterization of ZnO particles was carried out including Fourier Transform Infrared Spectroscopy (FTIR) and Particle Size Analyzer (PSA). In this study, the total polyphenol and flavonoid content in ethanol - water 1:1 (v/v) horn banana peel extract was higher at 4.944% and 5.940% than ethanol - water 2:1 (v/v) at 4.114% and 4.131%. Based on the results of FTIR testing, both samples have ZnO peaks where in ethanol - water 1:1 (v/v), 441 cm-1 and 619 cm-1, while ethanol - water 2:1 (v/v) is 428 cm-1. Then, from the PSA test results, the ethanol-water 1:1 (v/v) sample has a smaller average nanoparticle diameter of 135.6 nm than the ethanol-water 2:1 (v/v) sample which is 153.6 nm. ZnO nanoparticles were successfully synthesized using the natural capping agent banana peel extract. Different levels of secondary metabolites in each extract have an influence on the diameter of the synthesized ZnO nanoparticles.

Recent advances in synthesis and bio-applications of natural stabilizers for metal nanoparticles

Due to their exceptional physicochemical properties, the synthesis and application of metal nano-particles gained significant traction and a grip in industries and scientific fields or regions. However, the thermodynamic instability of metal nanoparticles poses or leads to challenges in their controlled synthesis and stabilization. To address this stability and the immobilization strategies, natural polymers such as cellulose, starch, alginate, chitosan, and hyaluronic acid have been explored for their non-toxic, biodegradable, and environmentally friendly characteristics. Recent advances in nanotechnology have led to an increased focus on these natural polymer’s utilization as effective stabilizers for diverse metal nanoparticles. This review comprehensively examines recent advances in utilizing these natural polymers as stabilizers for metal nanoparticles. Synthesis methods, stabilization mechanisms, and applications spanning catalysis, sensing, drug delivery, and biomedical imaging are discussed. Challenges such as scalability and reproducibility are addressed, alongside future directions for research and development. In this review, our goal is to encourage continued research and creativity in sustainable nanomaterials. By doing so, we hope to advance the development of adaptable and environmentally friendly nanoparticles that find applications across various industries.

Influence of planar defects on the mechanical behaviors of spherical metallic nanoparticles

Abstract In present study, we adopt molecular dynamics simulations to investigate the influences of typical planar defects, including twin boundaries (TBs), stacking faults (SFs) and grain boundaries (GBs), on the mechanical properties of fcc copper nanoparticles. Groups of nanoparticle samples, including defect-free single crystal and those with specific defects, are examined for elastic modulus, yield strength, and deformation mechanisms. Detailed results reveal that the elastic behavior of nanoparticles can be well described by a modified theoretical model regardless the type of defects. While the planar defects have negligible influence on the elastic modulus, they significantly enhance the yield strength of nanoparticles. Notably, nanoparticles containing fivefold TBs exhibit the highest yield stress, i.e. ∼17.0 GPa, even surpassing that of the defect-free counterparts, i.e. ∼10.0 GP. Analysis of atomic deformation unravels that the distinct yielding behaviors are attributed to the activation of different slip systems and the nucleation of dislocations at specific preferential sites. These findings highlight the potential of fabricating planar defects to tailor the mechanical properties of metallic nanoparticles for targeted applications in nanotechnology and materials science.

Oxidative stress-induced cytotoxicity of HCC2998 colon carcinoma cells by ZnO nanoparticles synthesized from Calophyllum teysmannii

The field of green synthesis, namely using plant extracts for the production of metal nanoparticles, is rapidly gaining traction. Therefore, this study investigated the process of producing zinc oxide nanoparticles (ZnO NPs) using a water-based extract derived from the stem bark of Calophyllum teysmannii. Notably, this is the first documented utilization of this particular plant source. The presence of a distinct Ultraviolet-Visible (UV-Vis) absorption peak at 372 nm provided evidence for the creation of ZnO nanoparticles. The X-ray Diffractometer (XRD) and Field Emission Scanning Electron Microscopy (FESEM) investigations indicated that the nanoparticles exhibited sizes ranging from 31.5 to 59.9 nm and had spherical morphologies. Energy Dispersive X-ray Diffractometer (EDX) analysis verified the elemental composition of the ZnO nanoparticles, whereas the Fourier Transform Infrared (FTIR) spectra showed clear peaks, demonstrating their production. The FTIR examination of the C. teysmannii extract revealed peaks at around 3370 cm− 1, indicating the presence of phenolic compounds. These chemicals are likely responsible for the reduction and stabilization of the ZnO NPs. The high-resolution X-ray Photoelectron Spectroscopy (XPS) spectra clearly revealed separate peaks corresponding to Zn 2p and O 1s, providing confirmation of the chemical states and bonding contexts. The Raman Spectroscopy analysis revealed a distinct peak at around 425 cm⁻¹, confirming the presence of the wurtzite structure. The harmful effects of ZnO nanoparticles on HCC2998 (a kind of human colon cancer) and Vero (a type of monkey kidney epithelial) cells were evaluated using 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT), dichlorodihydrofluorescein diacetate (DCFH-DA), and boron-Dipyrromethene (BODIPY) assays. The cancer cells underwent cell death due to oxidative stress in a dose-dependent manner, as confirmed by microscopic and flow cytometry investigations.

MoS2-Based NH3 Sensor for In Situ Helicobacter pylori Detection.

Detection of Helicobacter pylori is essential for the prevention of gastric cancer. By detecting the metabolized NH3, it was able to noninvasively reveal the state of H. pylori; however, it is still a challenge since the metabolized NH3 concentration is much lower for conventional gas sensors. Herein, we developed a MoS2-based NH3 sensor for continuous, real-time monitoring of H. pylori growth. The atomic thin layer and the all-exposed surface of MoS2 facilitate NH3 adsorption and charge transferring. A high-response NH3 sensor was prepared by surface decoration of MoS2 by depositing metal nanoparticles. The Fe-decorated MoS2 sensor outperformed with a high response of 40.9% for 5.7 ppm of NH3 at 25 ± 2 °C, low LOD (6.2 ppb), and long-term stability with a response of 12.5% for 5.7 ppm of NH3 after 5 months. The Fe-decorated MoS2 sensor was applied to the detection of H. pylori and the real-time in situ monitoring of its 92 h growth cycle. The NH3 release curve of the exponential phase during H. pylori growth was continuously monitored, and the NH3 concentration was quantified. The maximum specific rate of NH3 release was 0.195 ± 0.005 h-1, which is well-consistent with the nature of H. pylori growth. This study opens up a technological roadmap for noninvasive detection of H. pylori in the future.