Abstract: Industrial dye wastewater poses severe environmental and health risks, creating an urgent demand for efficient and sustainable remediation technologies. Herein, hierarchically porous hollow TiO2 nanofibers (HNFTi) were constructed through electrospinning and coupled with blue-, green-, and orange-emissive graphene quantum dots (b-, g-, and o-GQDs) to fabricate visible-light-responsive heterojunction photocatalysts. By tailoring the surface functional groups and heteroatom doping of GQDs, a progressive fluorescence redshift was achieved, which effectively narrowed the bandgap and extended visible-light absorption. Benefiting from the synergistic effects of the hierarchically porous hollow TiO2 architecture and the fluorescence-tuned GQDs, the resulting composites exhibited enhanced light harvesting, accelerated charge separation, and improved interfacial charge transfer. Among them, the 0.5 wt% o-GQDs/HNFTi composite showed the best photocatalytic performance, delivering a methylene blue degradation efficiency of 99.5% within 2 h under visible-light irradiation, markedly higher than that of pristine HNFTi (77.7%). Photoelectrochemical and Kelvin probe force microscopy analyses further confirmed the promoted carrier dynamics and effective interfacial separation of photogenerated electron-hole pairs. This work provides a feasible strategy for integrating structural engineering and fluorescence modulation to develop high-performance TiO2-based photocatalysts for wastewater treatment.

Abstract: Cancer remains a major global health challenge, and the limitations of conventional therapies have intensified interest in treatment strategies that combine improved selectivity with reduced systemic toxicity. Photothermal therapy and photodynamic therapy have emerged as minimally invasive approaches capable of achieving spatiotemporally controlled tumour ablation. In this context, molybdenum disulfide (MoS₂), a transition metal dichalcogenide with strong near-infrared absorption, high photothermal conversion efficiency, and versatile surface chemistry, has gained increasing attention as a multifunctional platform for drug delivery and light-triggered cancer therapy. This review examines recent advances in engineered MoS₂ nanoplatforms for drug-enhanced cancer phototherapy, with emphasis on how surface design and therapeutic cargoes mechanistically amplify light-triggered tumour killing. Approaches such as polymer coatings, biomimetic membranes, targeting ligands, chemotherapeutic agents, nucleic acids, and photosensitisers have been explored to improve colloidal stability, tumour targeting, immune evasion, and stimulus-responsive drug release, while also adding complementary cytotoxic pathways such as chemotherapy, ROS generation, or gene silencing. Available in vitro and in vivo studies indicate that these systems generally exhibit favourable short-term biocompatibility under the tested conditions and can produce significant antitumour effects following irradiation. The review also discusses key biological barriers and translational challenges, including biodistribution, long-term safety, reproducibility, and regulatory considerations, highlighting opportunities for the development of clinically viable MoS₂-based phototherapeutic platforms.

Abstract: The performance and mechanism of heterogeneous catalytic reactions are fundamentally governed by the formation, stability, and reactivity of transient surface intermediates. These species—such as isocyanates, alkyl groups, carboxylates, formates, carbonates, alkoxy and acyl intermediates—often exist at low concentrations and with short lifetimes, making their identification challenging. This review summarizes current knowledge on the formation, spectroscopic identification, and thermal behavior of these intermediates on metal single crystals, metal nanoparticles, and oxide-supported catalysts. Emphasis is placed on key reactions including CO and NO oxidation–reduction, CO and CO₂ hydrogenation, Fischer–Tropsch–related pathways, and reforming of methane and light alcohols. Advanced surface-sensitive techniques (TDS, XPS, UPS, IR, HREELS) are highlighted for their role in elucidating intermediate structures and reaction pathways. The review also discusses how metal–support interactions, particle size, and surface morphology influence intermediate stability and catalytic selectivity. Overall, the work provides a comprehensive framework for understanding how transient surface complexes control technologically important catalytic transformations.

Abstract: Virus-like particles (VLPs) are self-assembling protein nanostructures that replicate the structural precision of viral capsids while lacking genetic material, rendering them inherently safe and highly modular biomaterials. Their genetically encoded architecture enables precise control over size, symmetry, mechanical stability, surface topology, and internal cavity volume, positioning VLPs as programmable protein-based nanocarriers for chemotherapeutic delivery. Recent advances in capsid engineering, biorthogonal conjugation, and template-guided assembly have enabled fine tuning of cargo loading, targeting ligand display, and stimuli-responsive drug release. Unlike many synthetic nanocarriers, VLPs offer atomically defined structure–function relationships, allowing rational modulation of biodistribution, cellular uptake, immune recognition, and therapeutic performance. This review examines VLPs as engineered protein biomaterials for precision chemotherapy, highlighting strategies for internal cargo integration, interfacial surface modification, mechanical reinforcement, and microenvironment-triggered release. Here we discuss how physicochemical parameters govern biological interactions and translational feasibility. Clinical progress underscores both the promise and remaining challenges of scalable manufacturing and immune modulation. By integrating biomaterials design principles with translational constraints, this review outlines a framework for the rational development of clinically viable VLP-based chemotherapeutic systems.

Abstract: Commercially available drug-eluting stents still suffer from poor blood compatibility, polymer coating delamination, cracking and lack of stability during and after stent implantation that led to adverse events such as stent thrombosis and in-stent restenosis. This article highlights the advantages of using silicon nanofilament (SiNf) as an interface between stent surface and drug-in-polymer coating or bloodstream. The SiNf was successfully formed on the surface of Co-Cr substrate via one-step simple method. The morphology of the filaments showed nanosized structures with nano-gaps between the filaments. After coating the nanofilaments with a mixture of sirolimus and poly(D,L-lactide), an interlocking mechanism was established in which the coating penetrates the nano-gapes between the filaments. Therefore, the presence of SiNf enhanced the coating stability with no coating delamination whereas, the control substrate presented 97% of coating delamination. For stent application, the SRL-in-PDLLA matrix was coated on stent platform with smooth and uniform morphology without webbing between stent struts. After stent ballooning, the control stent presented cracking and peeling of the polymer coating from the surface whereas, the SiNf-modified stent did not show any sign of these unfavorable defects. Moreover, the platelet adhesion on the SiNf surface showed a lower number with round shape morphology compared to control Co-Cr. This suggests that modifying the substrates with SiNf could act as a universal coating for reinforcing the polymer coating stability, prevent coating defects that accompany stent ballooning, and improve the blood compatibility of the material surfaces that could have various applications to medical implants and devices.

Abstract: Nanoparticles offer a versatile platform for the selective eradication of pathogenic or diseased cells by integrating therapeutic payload delivery with precision targeting. Precision targeting can be achieved (1) actively through ligand conjugation, (2) passively by exploiting the physiological abnormalities of diseased tissues, or (3) intrinsically through the innate biophysical properties of the nanoparticle. Intrinsically selective nanoplatforms (iNPs) are particularly advantageous when the disease-promoting agent does not possess distinct surface markers, such as in the case of certain “untargetable cancers” or cancers without known targets. Indeed, nanocarriers for chemotherapeutic or gene delivery have achieved selective cancer cell apoptosis without requiring marker presentation, thereby expanding the therapeutic window of the payload. Disease-promoting agents whose physical properties are different from those of healthy cells are also good candidates for intrinsic nanoparticle targeting. For example, antimicrobial nanomaterials have been designed to disrupt bacterial membranes and reduce the risk of antimicrobial resistance by leveraging stiffness differentials between bacterial cell walls and eukaryotic membranes. Nanoparticle systems with intrinsic targeting mechanisms can also enable non-invasive imaging with near-infrared fluorescence, MRI, and photoacoustic imaging for real-time biodistribution tracking and treatment monitoring. This review synthesizes current innovations in nanoplatform design with intrinsic targeting capabilities, spans applications in infectious and non-communicable diseases, and discusses emerging strategies to enhance specificity, overcome resistance, and translate these platforms toward clinical and field deployment.

Abstract: Green synthesis of metal-based nanomaterials has emerged as an eco-friendly alternative to conventional chemical routes due to its sustainability, cost-effectiveness, and reduced environmental impact. In the present study, nickel nitrate nanoparticles (Ni(NO₃)₂ NPs) were biosynthesized using Tridax procumbens leaf extract as a reducing and stabilizing agent. The formation of Ni(NO₃)₂ nanoparticles was confirmed through UV–Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray analysis (EDAX). XRD analysis revealed the crystalline nature of the synthesized nanoparticles with a face-centered cubic structure, while SEM images showed agglomerated, quasi-spherical particles with rough and porous surfaces. FTIR analysis confirmed the involvement of plant-derived phytochemicals in nanoparticle stabilization. The biosynthesized Ni(NO₃)₂ nanoparticles exhibited significant antimicrobial activity against selected bacterial and fungal strains in a concentration-dependent manner. Furthermore, the photocatalytic performance of the nanoparticles was evaluated for the degradation of Yellow RGB Red Azo dye under visible light irradiation. The degradation efficiency was strongly influenced by pH and catalyst dosage, with maximum degradation (~98%) achieved at alkaline pH (10) and higher catalyst loading. Kinetic studies demonstrated that the dye degradation followed pseudo-first-order kinetics. Scavenger experiments revealed that hydroxyl and superoxide radicals played a dominant role in the photocatalytic degradation mechanism. The results highlight the potential of Tridax procumbens-mediated Ni(NO₃)₂ nanoparticles as efficient, sustainable materials for antimicrobial applications and wastewater treatment.

Abstract: This study successfully developed a novel tumor-associated macrophages (TAMs)-targeting nanoplatform-sialic acid-disulfide bond-camptothecin (SA-SS-CPT) nanowires. This system significantly improved the solubility and bioavailability of camptothecin (CPT) and achieved active targeted drug delivery by utilizing sialic acid as a targeting ligand to specifically recognize the highly expressed Siglec-E receptor on TAMs. Upon internalization into TAMs, the disulfide bond in the SA-SS-CPT nanowires was cleaved in response to intracellular glutathione (GSH), leading to the controlled re-lease of CPT. SA-SS-CPT induced DNA damage in TAMs, thereby activating the cGAS-STING signaling pathway, promoting the polarization of TAMs toward the M1 phenotype, enhancing pro-inflammatory and anti-tumor immune responses, and effec-tively inhibiting tumor immune escape. Furthermore, the SA-SS-CPT nanowires syner-gistically enhanced the efficacy of PD-L1 blockade immunotherapy, collectively remod-eling the tumor immune microenvironment and ultimately facilitating significant tumor clearance.

Abstract: Hydrophobic carbon quantum dots (hbCQDs) with tunable photoluminescence were synthesized via a solvothermal approach and further hybridized with Rhodamine B (RhB) to extend emission into the visible range. The hbCQDs exhibit quasi-spherical morphology with an average particle size of 8 nm and predominantly disordered graphitic structure, as confirmed by TEM and XRD analyses. FTIR and XPS characterizations reveal surface functional groups including C–N, C=O/C–O, and S–H, which govern the photoluminescence properties. Pure hbCQDs display blue emission at 453 nm under excitation, with a quantum yield (QY) of 6.2%. Incorporation of RhB leads to dual-emission behavior: the surface-state emission remains in the blue region, while molecular-state emission from RhB appears in the orange-red region. The 0.2 mL RhB–CQD composite exhibits optimal properties, including a QY of 13% and a production yield of 82%, emitting white light under 365 nm UV excitation. Increasing RhB loading to 0.4 mL results in a shift of emission peaks and a reduced QY (<9%), with weaker orange fluorescence. These findings demonstrate that controlled RhB hybridization effectively tunes the emission spectrum of hbCQDs, offering a simple and reproducible strategy to achieve dual-color and white-light emission. The optimized hbCQDs/RhB composites hold significant potential for applications in hydrophobic media-compatible organic optoelectronics, light-emitting devices, and bioimaging.

Abstract: Polyaniline-cadmium sulfide-gold (PANI-CdS-Au) nanocomposites were synthesized with varying Au loadings (0.023, 0.046, 0.092)wt% to enhance antibacterial performance. Structural (FTIR, XRD) and morphological (FE-SEM) analyses confirmed successful formation, strong interactions among components, and homogeneous nanoparticle dispersion. UV–Vis spectra revealed gold surface plasmon resonance and polaronic transitions consistent with PANI emeraldine base. XRD results showed the expected wurtzite CdS and fcc Au phases. Agar well diffusion tests against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) demonstrated that the 0.092 wt% of Au composite produced the largest inhibition zones at 100 µg mL⁻¹ (E. coli: 36 mm; S. aureus: 24 mm), with the same trend at 25 µg mL⁻¹. These results position PANI-CdS-Au nanocomposites as promising antibacterial materials; additional cytotoxicity assays are recommended for biomedical translation.

Abstract: Background/Objectives: Essential oils (EOs) have multi-target antifungal activity, but their translation is limited by volatility and poor aqueous dispersibility. Randomly methylated β-cyclodextrin inclusion (RAMEB) may enhance effective exposure and thereby alter susceptibility, stress responses, and biofilm outcomes in a species-dependent manner. This study quantified species-specific planktonic and biofilm susceptibility to four EOs and their RAMEB complexes across clinically relevant Candida species. Methods: Lavender (L), lemon balm (B), peppermint (P), and thyme (T) oils and their RAMEB complexes (RL, RB, RP, RT) were tested against C. albicans, and non-albicans Candida. Susceptibility thresholds were used to derive phase plasticity metrics. Functional inhibition was assessed via planktonic metabolism/viability and established-biofilm metabolism/viability/biomass. Mechanistic signatures were captured by ROS/RNS measurements and qPCR of antioxidant genes (CAT1, GPX1, SOD1). Mixed-effects models and multivariate/unsupervised and interpretable classification approaches (k-means, PCA, CRT) were used to integrate endpoints and stratify response phenotypes. Results: Susceptibility thresholds were strongly species-structured (lowest MIC90/EC10 for C. albicans; higher thresholds and broader sublethal windows in non-albicans species). RAMEB complexation produced formulation-dependent shifts in efficacy, with RT emerging as the most consistent broad-spectrum inhibitory condition across compartments. Biofilm biomass was comparatively insensitive even when viability was suppressed, indicating decoupling of structural biomass from biocidal activity. Mechanistic signatures were broadly conserved across species and linked to antioxidant-program engagement, with CAT1-related rules contributing to responder/tolerant classification. Conclusions: Integrating MIC/EC plasticity with functional and mechanistic markers supports rational selection of EO formulations; RAMEB complexation particularly RT prioritizes candidates for further pharmaceutical optimization while highlighting species-specific vulnerabilities.

Abstract: Understanding the interactions of nanomaterials with complex tumour models is essential for advancing their use in nanomedicine. Calcium fluoride nanoparticles doped with neodymium and yttrium (CaF₂:Nd³⁺, Y³⁺) exhibit promising properties for biomedical applications, particularly for optical sensing and tagging. This study investigates their interaction with 3D cell spheroids derived from breast cancer (MCF-7) and brain cancer (U-87 MG) cell lines as tumour models. Specific protocols have been developed in Total-reflection X-Ray Fluorescence (TXRF) to evaluate nanoparticles’ internalisation and diffusion within spheroids by quantifying the concentrations of Ca, Nd, and Y taken up by the cells. Minimal background interference enabled precise multi-element detection in low-volume biological samples, yielding very low detection limits and minimal uncertainties. The study demonstrates the effectiveness of TXRF for quantifying rare-earth-doped nanoparticles in 3D cancer models and reveals that, although both cell lines permit nanoparticle diffusion into cells, higher accumulation is observed in glioblastoma cell spheroids. A Weibull diffusion model was applied to help understand the observed internalisation kinetics of nanoparticles into U-87 MG and MCF-7 spheroids. The relevant differences suggest cell-line-dependent uptake behaviour, potentially influenced by differences in cellular architecture, the porosity of the generated spheroid, and its intercellular 3D microstructure. These findings highlight the importance of tumour-specific interactions in the investigation of nanoparticle systems for targeted cancer diagnostics and therapeutics.

Abstract: Perovskite oxide photoanodes are attractive for alkaline water oxidation but are commonly limited by interfacial recombination and sluggish charge transfer. Here we enhance anisotropic SrTiO₃ (STO) photoelectrodes via Al doping and identify an optimal composition at 4% Al. In 0.1 M NaOH (pH 13) under simulated AM 1.5G illumination, 4% Al:STO exhibits the highest transient/steady photocurrent and the best LSV performance among all samples, together with a markedly reduced interfacial impedance, indicating accelerated charge extraction and transfer. High-resolution XPS confirms Al incorporation and reveals suppressed Ti3⁺-related defect states with modified oxygen-associated surface species, consistent with mitigated trap-assisted recombination. Band-structure analysis shows a negative shift in flat-band potential and slight band-gap narrowing after Al doping, providing more favorable carrier energetics. Steady-state and time-resolved photoluminescence further demonstrate strong PL quenching and prolonged carrier lifetime for 4% Al:STO. ECSA analysis suggests increased electrochemically accessible surface sites at the optimal doping level. Overall, moderate Al doping synergistically tunes defects, band energetics, and interfacial kinetics to improve STO photoanodes for solar water splitting.

Abstract:

Electrospinning and electrospraying nanotechnologies were used to valorise agro-industrial residues into biohybrid controlled-release polyphenol (CRP) scaffolds. Four polyhydroxybutyrate ± polycaprolactone (PHB±PCL) architectures were fabricated that differed in polymer phase, Klason lignin from hazelnut-shell (HS-KL) presence vs absence and co-location with grape-pomace polyphenols (GP-PP), as well as distribution between fibres and bead-like depots. Scaffolds were characterised using optical microscopy/stereomicroscopy/SEM, FTIR, UV/VIS spectroscopy and dynamic water contact angle (absorption). GP-PP release was monitored for 14 days at ~25 °C and 37 °C, the latter representing shallow-soil hot-spell conditions in Mediterranean zones. All matrices exhibited multimodal release, with modest initial bursts and three phases (burst, mid, and late tail), analogous to controlled-release fertiliser profiles. At ~25 °C, the PHB/PCL matrix with HS-KL confined to PHB fibres and GP-PP in large PCL beads showed the highest total GP-PP release, whereas the architecture with HS-KL and GP-PP co-located in both PHB and PCL fibres and in PCL depots combined high total release with a smoother, well-metered late phase. At 37 °C, this HS-KL-GP-PP co-located scaffold was the most robust, retaining the highest total and late tail release. These results identify HS-KL-GP-PP co-located PHB/PCL architectures as promising carriers for temperature-resilient delivery of bioactive polyphenols in Mediterranean agrosystems.

Abstract: Zinc oxide nanoparticles (ZnO NPs) have attracted significant attention due to their distinctive physicochemical characteristics and growing relevance across biomedical, environmental, and industrial domains, prompting sustained research into their design and functional performance. This review systematically examines reported synthesis approaches for ZnO nanoparticles, alongside commonly employed characterization techniques used to evaluate their structural, optical, and surface properties, with emphasis on how these parameters influence biological interactions. The article consolidates findings from recent studies describing the antimicrobial, anticancer, and drug-delivery-related functionalities of ZnO nanoparticles, highlighting proposed mechanisms such as reactive oxygen species generation, surface-mediated interactions, and controlled payload release. Additionally, the review summarizes existing evidence regarding biocompatibility, toxicity concerns, and stability issues that currently limit translational implementation. Collectively, the analyzed literature indicates that controlled synthesis and surface engineering play a critical role in tailoring ZnO nanoparticle performance for specific biomedical applications. In conclusion, this review identifies key challenges and emerging opportunities associated with ZnO nanoparticles and underscores the need for standardized evaluation frameworks and mechanistic clarity to support their responsible integration into future healthcare technologies.

Abstract: Upconverting nanoparticles, which transform low-energy infrared radiation into high-energy visible or UV light, show great potential in today’s technology. High-quality upconversion colloid (UCC) consisting of lanthanide-based nanoparticles with a diameter of ~10 nm was obtained using a combination of two processes, high-temperature coprecipitation and hydrothermal treatment in an autoclave. The UCC was then PEGylated with PEG-alendronate (PEG-Ale) to facilitate its dispersion in aqueous cell culture media intended for in vitro cell uptake assays. The surface modification of the nanoparticles increased both the colloidal stability in water and the upconversion emission by mitigating surface quenching. UCC@Ale-PEG was characterized by transmission and scanning electron microscopy, dynamic light scattering, and by fluorescence microscopy detecting upconversion photoluminescence emission. The results of an in vitro assay revealed that this new generation of UCC can be internalized by various cell types including epithelial cells, macrophages, and glioma cells, upon several hours of exposure, suggesting broad application potential of this type of UCC in biomedicine, bioengineering, and environmental sciences.

Abstract: In this study the photocatalytic activity as a function of effective irradiance, photocatalytic quantum yield and reactant coverage was thoroughly assessed for the proper photoreactor (PhR) selection. PhR selection is a preponderant stage for photocatalytic processes, which has been an aspect not studied in detail in various scientific investigations. The emitted wavelength and effective irradiance of several PhRs, equipped with fluorescent and light emitting diodes (LEDs) lamps, were tested in the photodegradation of methylene blue (MB) in solid phase using AgTiC. Among all tested PhRs the one equipped with the low-pressure Hg lamp enhanced the photodegradation of MB. The above is due to the Hg lamp emitted UV-type radiation, which promotes the simultaneous photoactivation of the TiO2 and the surface plasmon resonance phenomenon of the Ag nanoparticles. Based on this study, it was determined that high values of effective irradiance promoted photocata-lytic activity because of the greater amount of photogenerated species [e-/h+]. Also, the ef-fective irradiance on the proper photocatalytic material slows down the recombination rate of the [e-/h+]. A kinetic photocatalytic model (KPM) was proposed to the description of photocatalytic reactions as a function of the effective irradiance, photocatalytic quantum yield and reactant coverage considering photocatalytic pseudo steady state according to the reactant equilibrium coverage (Langmuir isotherm) and the transfer processes of the photoinduced charge carrier species.

Abstract: Ni@TiO₂ core–shell nanoparticles were synthesized by magnetron sputtering and their structure verified by HRTEM and EDS analysis. The thermal stability of these particles was investigated using in situ TEM annealing and compared with that of pure Ni nanoparticles. While pure Ni particles sinter already at 450 °C and exhibit significant growth at 800 °C, Ni@TiO2 nanoparticles remain stable up to 700 °C, with the sintering onset between 700 and 800 °C. A simple thermal-mismatch model was applied to explain the stabilizing effect of the TiO2 shell, demonstrating that differences in thermal expansion between Ni and TiO2 generate interface stresses sufficient to crack the shell after the amorphous–rutile transformation. The TiO2 coating effectively delays Ni coalescence by 250 °C relative to bare Ni, highlighting its role as a protective shell against high-temperature sintering.

Abstract:

Bacterial cellulose (BC) is an attractive biopolymeric scaffold for the development of functional membranes due to its high purity, nanofibrillar network, mechanical robustness, and biocompatibility. In this work, we report the production and characterization of BC membranes functionalized with silver nanoparticles (AgNPs) generated through a plant-mediated green synthesis strategy, with particular emphasis on maximizing nanoparticle incorporation within the BC matrix. Mint (Mentha spicata) and avocado (Persea americana) extracts were employed as dual reducing and stabilizing agents for AgNP formation, enabling nanoparticle synthesis under mild and environmentally benign conditions. AgNP formation was first investigated in aqueous media as a function of silver precursor concentration, pH, and temperature, and monitored by UV–Vis spectroscopy through localized surface plasmon resonance (LSPR) features. Neutral pH (pH 7) and moderate temperature (23 °C) were identified as optimal conditions, yielding well-defined LSPR indicative of efficient and controlled nanoparticle formation. Two strategies for BC functionalization were subsequently compared: post-synthesis immersion of BC membranes in AgNP suspensions and in situ synthesis of AgNPs directly within the BC network. Spectroscopic analysis demonstrated that in situ synthesis enables significantly higher effective nanoparticle loading and a more homogeneous distribution throughout the BC scaffold, compared with the immersion approach.The resulting BC–AgNP composite membranes were subsequently evaluated for their antibacterial efficacy against Escherichia coli. Antibacterial performance was assessed using two complementary experimental stups. In the first, composite membranes were placed on agar surfaces uniformly seeded with E. coli, and the diameter of the resulting inhibition zones was measured following a defined incubation period as an indicator of bacteriostatic and bactericidal activity. In the second model, the BC–AgNP membranes were directly introduced into liquid cultures of E. coli, and bacterial growth was quantified by measuring the optical density (OD) of the cultures after incubation. This dual assay approach allowed for evaluation of both surface- mediated inhibition and the effects of AgNP release on planktonic bacterial growth. Membranes functionalized via in situ synthesis exhibited markedly enhanced antibacterial activity, with larger growth-inhibition zones and the absence of bacterial regrowth in both solid and liquid assays, confirming a predominantly bactericidal effect. Overall, this study demonstrates that combining bacterial cellulose with in situ green synthesis of silver nanoparticles is an effective strategy to maximize nanoparticle incorporation and produce robust antimicrobial membranes, offering strong potential for applications in wound dressings, filtration systems, antimicrobial packaging, and other sustainable functional materials.

Abstract: The accurate monitoring and dynamic analysis of metal ions are of considerable practical significance in environmental toxicology and life sciences. Colorimetric analysis and surface-enhanced Raman scattering (SERS) sensing technologies, utilizing the aggregation effect of gold and silver nanoparticles (Au/Ag NPs), have emerged as prominent methods for rapid metal ion detection, serving as effective complements to conventional bulky instrumental analysis techniques. This is propelled by their distinctive localized surface plasmon resonance (LSPR) response and electromagnetic field enhancement mechanisms. This article evaluates contemporary optical sensing methodologies utilizing aggregation effects and their advancements in the detection of diverse metal ions. It comprehensively outlines methodological advancements from nanomaterial fabrication to signal transduction, encompassing approaches such as biomass-mediated green synthesis and functionalization, targeted surface ligand engineering, digital readout systems utilizing intelligent algorithms, and multimodal synergistic sensing. Recent studies demonstrate that these techniques have attained trace-level identification of target ions regarding analytical efficacy, with detection limits generally conforming to or beyond applicable environmental and health safety regulations. Moreover, pertinent research has enhanced detection linear ranges, anti-interference properties, and adaptability for point-of-care testing (POCT), validating the usefulness and developmental prospects of this technology for analysis in complicated matrices.