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Physical activity has been considered an important non-medication intervention in preserving mnemonic processes during aging. However, how aerobic exercise promotes such benefits for human health remains unclear. In this study, we aimed to explore the neuroprotective and anti-inflammatory effects of aerobic exercise against lipopolysaccharide (LPS)-induced amnesic C57BL/6J mice and BV-2 microglial cell models. In the in vivo experiment, the aerobic exercise training groups were allowed to run on a motorized treadmill 5 days/week for 4 weeks at a speed of 10 rpm/min, with LPS (0.1 mg/kg) intraperitoneally injected once a week for 4 weeks. We found that aerobic exercise ameliorated memory impairment and cognitive deficits among the amnesic mice. Correspondingly, aerobic exercise significantly increased the protein expressions of FNDC5, which activates target neuroprotective markers BDNF and CREB, and antioxidant markers Nrf2/HO-1, leading to inhibiting microglial-mediated neuroinflammation and reduced the expression of BACE-1 in the hippocampus and cerebral cortex of amnesic mice. We estimated that aerobic exercise inhibited neuroinflammation in part through the action of FNDC5/irisin on microglial cells. Therefore, we explored the anti-inflammatory effects of irisin on LPS-stimulated BV-2 microglial cells. In the in vitro experiment, irisin treatment blocked NF-κB/MAPK/IRF3 signaling activation concomitantly with the significantly lowered levels of the LPS-induced iNOS and COX-2 elevations and promotes the Nrf2/HO-1 expression in the LPS-stimulated BV-2 microglial cells. Together, our findings suggest that aerobic exercise can improve the spatial learning ability and cognitive functions of LPS-treated mice by inhibiting microglia-mediated neuroinflammation through its effect on the expression of BDNF/FNDC5/irisin.

Abstract This review reports diverse microfluidic systems utilizing surface-enhanced Raman scattering (SERS) detection for disease diagnosis. Integrating SERS detection technology, providing high-sensitivity detection, and microfluidic technology for manipulating small liquid samples in microdevices has expanded the analytical capabilities previously confined to larger settings. This study explores the principles and uses of various SERS-based microfluidic devices developed over the last two decades. Specifically, we investigate the operational principles of documented SERS-based microfluidic devices, including continuous-flow channels, microarray-embedded microfluidic channels, droplet microfluidic channels, digital droplet channels, and gradient microfluidic channels. We also examine their applications in biomedical diagnostics. In conclusion, we summarize the areas requiring further development to translate these SERS-based microfluidic technologies into practical applications in clinical diagnostics.

We demonstrated that the hybrid core–shell nanostructure of Fe3O4 (core) and gold (shell) could be a good substrate candidate both for metal-enhanced fluorescence (MEF) and surface-enhanced Raman spectroscopy (SERS). The magnetic properties of the core material could provide functionalities such as the magnetically induced aggregation/distribution of nanostructures to increase the hot-spot density, while the nano-thickness gold shell allows for the plasmonic enhancement of both fluorescence and SERS. The gold-capped magnetic (Fe3O4) nanoparticles (GMPs) were facilely synthesized using a newly developed chemical method. The relative molar ratio of the constituent materials of the core–shell composite was optimized for tuning the plasmonic resonance wavelengths for MEF and SERS. We employed GMP-based MEF to detect alpha-fetoprotein (AFP), with concentrations ranging from 0.05 to 1000 ng/mL, and obtained a limit of detection (LOD) as low as 3.8 × 10−4 ng/mL. The signal enhancement factor (EF) in the GMP-based MEF was 1.5 at maximum. In addition, the GMPs were used in SERS to detect rhodamine B (RhB). Its LOD was 3.5 × 10−12 M, and the EF was estimated to be about 2 × 108. The hybrid core–shell nanoparticles could find potential applications in diagnostic assays based on MEF and SERS in various fields such as food verification, environmental testing/monitoring, and disease diagnosis.

To date, a large number of photosensitizers (PS) have introduced heavy atoms to improve the ISC process and 1O2 generation. However, they often show low efficiency in hypoxic conditions, aggregate states, and turn-off PDT in the dark. Besides that, the toxicity of heavy metals is also concerned. Therefore, we developed lysosome-targeted heavy-metal-free PS (3S and 4S) based on thionated naphthalimide for hypoxic cancer photodynamic therapy (PDT), not only under white light but also in the dark via thermal-induced 1O2 generation. AIEgen (3O and 4O) were prepared for studying the PDT action of PSs (3S and 4S) in lysosome and aggregate state. We also examined the photophysical properties of AIEgen (3O and 4O) and PS (3S and 4S) by UV–vis absorption, fluorescent emission spectra, and theoretical calculations.

Many scientists are increasingly interested in on-site detection methods of phenol and its derivatives because these substances have been universally used as a significant raw material in the industrial manufacturing of various chemicals of antimicrobials, anti-inflammatory drugs, antioxidants, and so on. The contamination of phenolic compounds in the natural environment is a toxic response that induces harsh impacts on plants, animals, and human health. This mini-review updates recent developments and trends of novel plasmonic resonance nanomaterials, which are assisted by various optical sensors, including colorimetric, fluorescence, localized surface plasmon resonance (LSPR), and plasmon-enhanced Raman spectroscopy. These advanced and powerful analytical tools exhibit potential application for ultrahigh sensitivity, selectivity, and rapid detection of phenol and its derivatives. In this report, we mainly emphasize the recent progress and novel trends in the optical sensors of phenolic compounds. The applications of Raman technologies based on pure noble metals, hybrid nanomaterials, and metal–organic frameworks (MOFs) are presented, in which the remaining establishments and challenges are discussed and summarized to inspire the future improvement of scientific optical sensors into easy-to-operate effective platforms for the rapid and trace detection of phenol and its derivatives.

Facile detection of indoor semi-volatile organic compounds (SVOCs) is a critical issue to raise an increasing concern to current researchers, since their emissions have impacted the health of humans, who spend much of their time indoors after the recent incessant COVID-19 pandemic outbreaks. Plasmonic nanomaterial platforms can utilize an electromagnetic field to induce significant Raman signal enhancements of vibrational spectra of pollutant molecules from localized hotspots. Surface-enhanced Raman scattering (SERS) sensing based on functional plasmonic nanostructures has currently emerged as a powerful analytical technique, which is widely adopted for the ultra-sensitive detection of SVOC molecules, including phthalates and polycyclic aromatic hydrocarbons (PAHs) from household chemicals in indoor environments. This concise topical review gives updated recent developments and trends in optical sensors of surface plasmon resonance (SPR) and SERS for effective sensing of SVOCs by functionalization of noble metal nanostructures. Specific features of plasmonic nanomaterials utilized in sensors are evaluated comparatively, including their various sizes and shapes. Novel aptasensors-assisted SERS technology and its potential application are also introduced for selective sensing. The current challenges and perspectives on SERS-based optical sensors using plasmonic nanomaterial platforms and aptasensors are discussed for applying indoor SVOC detection.

This work introduces a facile geometry-controlled method for the fabrication of embossed and engraved polymeric moth-eye-inspired nanostructures in imprinting molds using anodic aluminum oxide (AAO) templates, resulting in a novel anti-reflective transparent coating. The moth-eye nanostructures are prepared directly on the surface of a flexible polyethylene terephthalate (PET) substrate. As a prerequisite procedure, a UV-curable polyurethane acrylate resin is spun on the PET. The shape of the moth-eye nanostructures can then be adjusted by controlling the size and shape of the nanopores in the AAO templates. Both embossed and concaved polymer moth-eye nanostructures were successfully mounted on a PET substrate. Embossed polymer replica molds were prepared using the AAO master templates in combination with an imprinting process. As revealed by field-emission electron microscope (FE-SEM) images, conical nanopatterns in the AAO template with a diameter of ~90 nm and a depth of ~100 nm, create a homogeneous embossed morphology in the polymer moth-eye nanostructure. The polymeric molds with the depths of 300 and 500 nm revealed the amalgamated structures in their apexes. In addition, a dip-imprinting process of the polymeric layers was implemented to yield a concaved mold by assembly on the surface of the 100 nm embossed polymer mold substrate. Considering that the embossed structures may be crumbled due to their protuberant shapes, the concaved geometries can have an advantage of stability in a certain application concerning physical degradation along with a higher transmission by ~2%, despite somewhat nonuniform structure. The experimental and theoretical results of this study indicate that this polymer layer has the potential for use in anti-reflective coating applications in transparent films.

Tris(hydroxymethyl)aminomethane ethylenediaminetetraacetic acid (Tris-EDTA), upon binding Cr(III) in aqueous solutions at pH 8.0 on silver nanoparticles (AgNPs), was found to provide a sensitive and selective Raman marker band at ~563 cm−1, which can be ascribed to the metal-N band. UV-Vis absorption spectra also supported the aggregation and structural change of EDTA upon binding Cr(III). Only for Cr(III) concentrations above 500 nM, the band at ~563 cm−1 become strongly intensified in the surface-enhanced Raman scattering spectra. This band, due to the metal-EDTA complex, was not observed in the case of 50 mM of K+, Cd2+, Mg2+, Ca2+, Mn2+, Co2+, Na+, Cu2+, NH4+, Hg2+, Ni2+, Fe3+, Pb2+, Fe2+, and Zn2+ ions. Seawater samples containing K, Mg, Ca, and Na ion concentrations higher than 8 mM also showed the characteristic Raman band at ~563 cm−1 above 500 nM, validating our method. Our approach may be useful in detecting real water samples by means of AgNPs and Raman spectroscopy.

This work presents a surface-enhanced Raman scattering (SERS) and density functional theory (DFT) study of a fipronil adsorbed on colloidal silver nanoparticles (AgNPs). A standard curve was established to quantify fipronil within a range of 0.0001–0.1 ppm (r2 ≥ 0.985), relying on the unique fipronil Raman shift at ~2236 cm−1 adsorbed on AgNPs. DFT calculations suggest that the nitrile moiety (C≡N) binding should be slightly more favorable, by 1.92 kcal/mol, than those of the nitrogen atom of the pyrazole in fipronil and Ag6 atom clusters. The characteristic peaks of the SERS spectrum were identified, and both the calculated vibrational wavenumbers and the Raman intensity pattern were considered. The vibrational spectra of fipronil were obtained from the potential energy distribution (PED) analysis and selective Raman band enhancement.

A surface-enhanced Raman scattering (SERS) detection method for environmental copper ions (Cu2+) was developed according to the vibrational spectral change of diethyldithiocarbamate (DDTC) on gold nanoparticles (AuNPs). The ultraviolet-visible (UV-Vis) absorption spectra indicated that DDTC formed a complex with Cu2+, showing a prominent peak at ~450 nm. We found Raman spectral changes in DDTC from ~1490 cm−1 to ~1504 cm−1 on AuNPs at a high concentration of Cu2+ above 1 μM. The other ions of Zn2+, Pb2+, Ni2+, NH4+, Mn2+, Mg2+, K+, Hg2+, Fe2+, Fe3+, Cr3+, Co2+, Cd2+, and Ca2+ did not produce such spectral changes, even after they reacted with DDTC. The electroplating industrial wastewater samples were tested under the interference of highly concentrated ions of Fe3+, Ni2+, and Zn2+. The Raman spectroscopy-based quantification of Cu2+ ions was able to be achieved for the wastewater after treatment with alkaline chlorination, whereas the cyanide-containing water did not show any spectral changes, due to the complexation of the cyanide with the Cu2+ ions. A micromolar range detection limit of Cu2+ ions could be achieved by analyzing the Raman spectra of DDTC in the cyanide-removed water.

In this study, the sorptive behavior of reduced sulfur compounds (RSC) was investigated using a combination of thermal desorber (TD) unit and gas chromatography (GC). To examine the sorptive properties of RSC on textile materials, two types of experiments were conducted under experimental conditions favorable for sorptive processes. In all the experiments, gaseous standards of hydrogen sulfide, methanethiol, dimethyl sulfide, and dimethyl disulfide were supplied to initiate the adsorption processes on textile pieces. The textile pieces were then forced to release those adsorbed RSC under a fixed condition. It was found that the extent of adsorption, if evaluated quantitatively, occurred at approximately 1/1000 to 1/100 of the level of RSC standards supplied originally to induce adsorption. It also indicated that RSC adsorption was affected very sensitively by the initial exposure durations to induce RSC adsorption with an exponential decrease in relative recovery (RR) values with increasing exposure time. The relative sorptive patterns, when compared between different RSCs, were affected most sensitively by such factors as molecular weight and/or physical contact conditions.

Host-guest complexation with various hydrophobic drugs has been used to enhance the solubility, permeability, and stability of guest drugs. Physical changes in hydrophobic drugs by complexation have been related to corresponding increases in the bioavailability of these drugs. Carbohydrates, including various derivatives of cyclodextrins, cyclosophoraoses, and some linear oligosaccharides, are generally used as host complexation agents in drug delivery systems. Many antibiotics with low bioavailability have some limitations to their clinical use due to their intrinsically poor aqueous solubility. Bioavailability enhancement is therefore an important step to achieve the desired concentration of antibiotics in the treatment of bacterial infections. Antibiotics encapsulated in a complexation-based drug delivery system will display improved antibacterial activity making it possible to reduce dosages and overcome the serious global problem of antibiotic resistance. Here, we review the present research trends in carbohydrate-based host-guest complexation of various hydrophobic antibiotics as an efficient delivery system to improve solubility, permeability, stability, and controlled release.

A facile, selective, and sensitive detection method for the Cu2+ ions in environmental and biological solutions has been newly developed by observing the unique CN stretching peaks at ~2108 cm−1 upon the dissociative adsorption of glycine (GLY) in hydrazine buffer on gold nanoparticles (AuNPs). The relative abundance of Cu species on AuNPs was identified from X-ray photoelectron spectroscopy analysis. UV-Vis spectra also indicated that the Au particles aggregated to result in the color change owing to the destabilization induced by the GLY-Cu2+ complex. The CN stretching band at ~2108 cm−1 could be observed to indicate the formation of the CN species from GLY on the hydrazine-covered AuNP surfaces. The other ions of Fe3+, Fe2+, Hg2+, Mg2+, Mn2+, Ni2+, Zn2+, Cr3+, Co2+, Cd2+, Pb2+, Ca2+, NH4+, Na+, and K+ at high concentrations of 50 µM did not produce such spectral changes. The detection limit based on the CN band for the determination of the Cu2+ ion could be estimated to be as low as 500 nM in distilled water and 1 µM in river water, respectively. We attempted to apply our method to estimate intracellular ion detection in cancer cells for more practical purposes.