Filtering Effect Research Articles

Larger cities host richer bee faunas, but are no refuge for species with concerning conservation status: Empirical evidence from Western Europe

In the context of worldwide biodiversity and wild bee decline, it is increasingly important to better understand the effect of land-use changes on wild bee communities at a global scale. To do so, we studied the effect of city area and urban green spaces layout on wild bee species richness and community composition, as well as on wild bee species with an unfavorable UICN conservation status. This study was based on a large European dataset encompassing 20 cities from France, Belgium and Switzerland. We found a mean wild bee species richness in cities of 96 ± 48 (SD), showing that this species richness was highly variable among cities. The main factor positively influencing wild bee species richness in cities was the area of the city. Conversely, species richness was not significantly related to the total area of urban green spaces in a given city, measured as the spatial extent of urban parks, wastelands and other semi-natural habitats, excluding urban private gardens. Species with conservation status were quite scarce in urban environments, especially when compared to the European Red List of Bees, and we could not link their presence to either city or urban green space area. Dissimilarities in wild bee species community compositions were not associated with any of the studied characteristics of cities. We found that the dissimilarity of wild bee community composition among cities was mainly driven by the rarest species, as the most common ones were found in a majority of the cities sampled. Overall, these results emphasize that larger cities host more wild bee species, but are no refuge for the ones with concerning conservation status. Thus, stakeholders are encouraged to design their cities in favor of biodiversity to better support wild bee communities, and perhaps mitigate the established effect of the urban ecological filter.

Series active filter using seven level packed U cell converter for power quality enhancement

In a low-voltage electrical grid, harmonics can have devastating effects on electrical equipment, leading to premature aging, reduced lifespan, and increased maintenance costs. To mitigate these issues, the control of a PUC-type multi-level converter series active filter is investigated in this study, with the primary objective of improving energy quality and reducing disturbed electrical voltage. The proposed filter utilizes a PUC-type voltage inverter controlled by PWM (Pulse Width Modulation) and employs two methods for identifying disruptive voltages: the instantaneous power (P-Q) method for harmonic compensation and the SRF (Synchronous Reference Frame) method. The simulation models are built using the MATLAB-Simulink software platform, which allows for accurate and efficient modeling of the filter's behavior under various operating conditions. The simulation results demonstrate the effectiveness of the series active filter in mitigating harmonics and voltage disturbances, highlighting its potential for real-world applications. The results show that the filter is able to significantly reduce the total harmonic distortion (THD) of the output voltage, improving the overall power quality. Furthermore, the simulation results also demonstrate the ability of the filter to quickly respond to changes in the grid voltage, making it an effective solution for addressing voltage disturbances. The study's findings suggest that the PUC-type multi-level converter series active filter has great potential for real-world applications in low-voltage electrical grids, particularly in systems that require high-quality power supply and efficient harmonic compensation. The proposed filter's ability to improve power quality and reduce harmonic distortion makes it a promising solution for mitigating the negative effects of harmonics on electrical equipment in low-voltage electrical grids.

Effect of activated carbon compaction on water filtration efficiency

Water contamination in rural Malaysian areas, mainly caused by logging activities leading to soil erosion and river pollution, presents a significant threat to water supplies. In response, a specialized activated carbon water filtering device was developed to target the absorption of organic molecules. The impact of compaction of activated carbon on water filtering efficiency was evaluated. Testing both compacted and uncompacted activated carbon filters with contaminated river water, the study utilized the Malaysia Department of Environment’s (DOE) water quality index (WQI) to assess filter effectiveness. The results revealed that water filtered through compacted activated carbon was clearer and less yellowish compared to the uncompacted counterpart. Moreover, the compacted filter showed higher dissolved oxygen levels, lower ammoniacal nitrogen levels, and a lower pH, resulting in a significantly higher WQI score of 80.4 compared to 78.8 for the uncompacted filter. Further analysis via an adsorption isotherm test demonstrated the superior ability of compacted activated carbon to absorb acetic acid, as evidenced by higher lines in the Freundlich isotherm model graphs. These findings emphasize the efficacy of compacted activated carbon in water filtration, advocating for its integration into filter construction to enhance water quality in rural regions.

Fast and eco-friendly synthesis of carbon dots from pinecone for highly effective detection of 2,4,6-trinitrophenol in environmental samples

ABSTRACT 2,4,6-Trinitrophenol (TNP) has high explosive risks and biological toxicity, and there has been considerable concern over the determination of TNP. In the present work, fluorescent carbon dots (CDs) stemmed from a green carbon source of pinecone by the facile hydrothermal approach. A novel environment- friendly fluorescent probe was developed to efficiently detect TNP by using the obtained CDs with remarkable fluorescence stability. The fluorescent CDs exhibited obvious excitation dependence with the highest peaks for excitation and emission occurring at 321 and 411 nm, respectively. The fluorescence intensity is significantly reduced by TNP owing to the inner filter effect with the CDs. The probe exhibited good linearity with TNP concentrations in the range of 0.025–20 μg mL−1, and the limit of detection was as low as 8.5 ng mL−1. Additionally, the probe proved successful in sensing TNP quantitatively in actual environmental samples with satisfied recoveries of 95.6–99.6%. The developed fluorescent probe offered an environment-friendly, efficient, rapid, and reliable platform for detecting trace TNP in the environmental field. Highlights Novel carbon dots were synthesised from green precursors of pineal powder. The highly effective quenching process was put down to the inner filter effect. The as-constructed fluorescent probe was successfully utilised for sensing 2,4,6-trinitrophenol in environmental samples. The proposed method was simple, rapid, efficient, economical, and eco-friendly.

One-step microwave-assisted synthesis of fluorescent carbon quantum dots for determination of ascorbic acid and riboflavin in vitamin supplements

The synthesis of carbon quantum dots (CQDs) using chemical precursors with different organic groups is a strategy to improve optical properties and expand applications in several fields of research such as Analytical Chemistry. Ascorbic acid and riboflavin are widely used in human food supplementation, making quality monitoring of these vitamin supplements relevant and necessary. In this work, disodium ethylenediaminetetraacetic, sodium thiosulfate and urea were applied to obtain CQDs through a single-step microwave-assisted synthesis. The CQDs were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction, infrared spectroscopy, zeta potential measurements, ultraviolet–visible spectroscopy and photoluminescence spectroscopy. The synthesized nanoparticles exhibited satisfactory and stable optical properties with luminescence at 430 nm, water solubility, and fluorescence quantum yield of 8.9 %. They were applied in the quantification of ascorbic acid and riboflavin in vitamin supplements. The fluorescence mechanisms observed were dynamic quenching for the CQDs/Cr(VI) sensor, followed by a return of fluorescence in the presence of ascorbic acid, and static quenching and inner filter effect in the interaction with riboflavin. Factorial designs 23 and 24 were used to optimize the analytical parameters. The CQDs/Cr(VI) sensor used in the determination of ascorbic acid, employing an on–off-on strategy, resulted in a linear range of 0.5 to 50 µg mL−1 and a limit of detection of 0.15 µg mL−1. The ratiometric fluorescence used in the determination of riboflavin resulted in a linear range of 0.1 to 7 µg mL−1 and a limit of detection of 0.09 µg mL−1. The analytical results for ascorbic acid were compared to the reference method of the Brazilian pharmacopeia, showing accuracy and precision according to the Brazilian Health Regulation Agency. Therefore, the synthesized CQDs were used to determine ascorbic acid and riboflavin in vitamin supplements, and the application of this nanomaterial can be expanded to different analytes and matrices, using simple and low-cost analysis techniques.

To beautify or uglify! The effects of augmented reality face filters on body satisfaction moderated by self-esteem and self-identification

Beautifying augmented reality face filters (AR-FF) have been linked to reduced body satisfaction, particularly in young women. Social comparison theory has been used to explain this negative effect through upward social comparisons against the beautified version of oneself. However, downward comparisons have received little attention, though their investigation could have critical theoretical and practical implications. This proof-of-concept study evaluated whether the type of face filter has an effect on body satisfaction in young female students (N = 76) by comparing uglifying (downwards) and beautifying (upwards) face filters in a between-subjects experiment. Additionally, the moderating roles of self-esteem and self-identification with a filtered depiction were investigated. Exposure to beautifying face filters decreased body satisfaction, while no significant effect was detected for uglifying face filters. Furthermore, the effect of beautifying face filters was moderated by self-esteem but not self-identification, while there were no interactions for uglifying face filters. Possible implications and future research opportunities are discussed.

Interaction of major saffron constituent safranal with trypsin: An experimental and computational investigation

Trypsin is a serine protease, an important digestive enzyme that digests the proteins in the small intestine. In the present study, we have investigated the interaction of safranal, a major saffron metabolite, with trypsin using spectroscopic and molecular docking analyses. Fluorescence emission spectra of trypsin were largely affected by the inner filter effect from safranal; that's why these were corrected using the standard procedure. The corrected fluorescence spectra have shown that the safranal quenched the intrinsic fluorescence of trypsin with a blue shift in the wavelength of emission maximum, which revealed that the microenvironment of the fluorophore became more hydrophobic. There was approximately 1: 1 fair binding between them, which increased with a rise in temperature. The interaction was favored, principally, by hydrophobic forces, and there was an efficient energy transfer from the fluorophore to the safranal. Synchronous fluorescence spectra suggested that the tryptophan residues were the major ones taking part in the fluorescence quenching of trypsin. Safranal also influenced the secondary structure of trypsin and caused partial unfolding. Molecular Docking and the Molecular Dynamics simulation of the free and complexed trypsin was also carried out. Safranal formed a stable, non-covalent complex within the S2′-S5′ subsite. Moreover, two nearby tyrosine residues (Tyr39 and Tyr151) stabilized safranal through π-π interactions. Additionally, the presence of safranal led to changes in the protein flexibility and compactness, which could indicate changes in the surrounding of tryptophan residues, impacting their fluorescence. Furthermore, a loss in compactness is in line with the partial unfolding observed experimentally. Thus, both experimental and computational studies were in good agreement with each other.

A ratiometric fluorescence probe based on the N, S co-doped dots and silver nanoclusters for the sensitive detection of Hg2+

Exploring highly sensitive fluorescence probe for mercury ion (Hg2+) determination is of great importance for environment system. In this work, a ratiometric fluorescence probe using N, S co-doped dots (NS-CDs) and silver nanoclusters (AgNCs) were successful constructed for the determination of Hg2+. In ratiometric fluorescent sensing system, as AgNCs was added to NS-CDs, fluorescence intensity at 442 nm can be reduced but in the increase of intensity at the 762 nm. Inner filter effect (IFE) was attributed to the mainly mechanism of action between the NS-CDs and AgNCs. Interestingly, the fluorescence of NS-CDs/AgNCs at 442 nm was gradually increase after the addition of Hg2+, while fluorescence at 762 nm was gradually quenched. Owing to the formation of NS-CDs/Agn-2NCsHg complexes, the NS-CDs/AgNCs led to a significant conformational change of Hg2+. According to the reverse change of two fluorescence peaks (I765/I442), a novel NS-CDs/AgNCs probe was designed for specific recognition of Hg2+ with the linear range from 0.1 to 90 μM and a limit detection (LOD) of 0.041 μM. Besides, NS-CDs/AgNCs was successful implemented to detect Hg2+ in the sample water with the good recoveries of 92.90–103.64 % (RSD≤4.62 %). Accordingly, the NS-CDs/AgNCs ratiometric fluorescent probe with simplicity, rapidity and high sensitivity exhibited a huge potentiality in the water environment analysis.

Multi-mode sensing platform for gallic acid determination based on the peroxidase-like activity of magnetic Fe3O4@Co/Ni/Al-LDH nanospheres

The determination of gallic acid (GA), one of the most prevalent antioxidants in various plants, provides information for food nutrition evaluation. A novel colorimetric, fluorescent, and smartphone multi-mode GA sensing platform based on Fe3O4@Co/Ni/Al-layered double hydroxide (LDH) nanospheres was designed in this study. The core-shell magnetic Fe3O4@Co/Ni/Al-LDH nanospheres were synthesized through a simple co-precipitation approach. They showed dominate peroxidase-like activities capable of oxidizing 3,3′,5,5′-tetramethylbenzidine (TMB) into a blue colored oxidation oxTMB. Meanwhile, the generated oxTMB could quench the fluorescence of neutral red via the inner filter effect. GA acted as an inhibitor to prevent the oxidation of TMB to oxTMB and restoring the fluorescence of neutral red. Under optimized conditions, the linear ranges were 0.5–120 μmol/L with detection limits of 0.137–0.415 μmol/L. Besides, the sensor exhibited good selectivity toward GA over various interferents. Moreover, it was successfully utilized to analyze GA in tea beverages with ideal recoveries of 92.8–105%, demonstrating good reliability and stability in practical applications. This study provided Fe3O4@Co/Ni/Al-LDH nanospheres as candidate nanozymes for the construction of biosensors. The multi-mode self-checking function and the “turn on” fluorescent sensing strategy offered this sensor superior anti-interference ability, and opens up a new strategy for the determination of antioxidants in foods.

Electrochemical polymerization of polyaniline/single-walled carbon nanotube bilayer films with enhanced thermoelectric properties

In this work, polyaniline (PANI) is coated on single-walled carbon nanotubes (SWCNT) via electrochemical polymerization method to fabricate PANI/SWCNT bilayer films with enhanced thermoelectric properties. Effects of deposition time and voltage, and acid types and concentrations on the thermoelectric properties of the films are studied. The results showed that PANI layer was effectively coated on the surface of SWCNT layer by electrochemical polymerization method. In addition, carrier transport and the electrical conductivity (σ) of the PANI/SWCNT bilayer film was improved due to interfacial π-π interaction between PANI and SWCNT, and the Seebeck coefficient (S) was increased due to the energy filtering effect at the interface of PANI/SWCNT. The maximum PF of PANI/SWCNT at room temperature was 155.3 ± 7.2 μW m−1 K−2 with the σ of 654.9 ± 41.8 S cm−1 and the S of 48.7 ± 0.5 μV K−1 when the deposition voltage and time were 1.0 V and 240.0 s using 0.5 M HCl, respectively. Finally, a self-powered thermoelectric device composed of five pairs of p-n junctions was prepared with PANI/SWCNT (1 V, 240 s) as the p-type legs and copper adhesives as the n-type legs, and the maximum output power was 0.27 μW at a temperature difference of 50 K. Therefore, this demonstrates that electrochemical polymerization is a feasible and effective way of fabricating conductive polymers/carbon nanotubes bilayer films with enhanced thermoelectric properties, which have potential application in powering wearable electronics.

Encapsulation of organic ultraviolet photoprotective actives into poly(methyl methacrylate) nanoparticles for sunscreen formulations

AbstractSkin cancer is the most common of all cancers worldwide. This way, it is mandatory to adopt an adequate sun protection routine, including sunscreen lotions. However, despite the proven effectiveness of numerous chemical filters, many of them are also known for their allergenic and carcinogenic potential effects, which can be mitigated by exploring some encapsulation routes. Thus, the present work evaluates the influence of seven distinct ultraviolet (UV) organic filters on the final particle size and molecular weight distributions of poly(methyl methacrylate) (PMMA) beads. Moreover, the sun protection factors (SPF) of the loaded nanoparticles are also evaluated when used for preparation of sunscreen formulations. The UV filters did not affect the course of MMA miniemulsion polymerizations significantly, enabling the synthesis of loaded nanoparticles. Nevertheless, adding the filters shifted the particle size distributions toward larger diameters, which are appropriate for cosmetic formulations. Based on the SPF analyses, it was also possible to observe a 12‐fold increase in the SPF values of the prepared formulations and an increase in the critical wavelength. Therefore, the in situ incorporation of distinct UV filters during miniemulsion MMA polymerizations constitutes a robust and versatile technology to produce PMMA nanoparticles loaded with UV filters for preparation of sunscreen formulations.

Smartphone-based ratiometric fluorescence sensor for sensitive visual detection of H2O2 and glucose based on B-CDs-Ag NPRs-OPD ternary system

A straightforward and highly sensitive ratiometric fluorescence sensor comprising blue emissive carbon dots, silver nanoprisms, and o-phenylenediamine (B-CDs-Ag NPRs-OPD) was developed for the detection of H2O2 and glucose. Ag NPRs were etched into Ag+ ions upon exposure to H2O2, which caused non-fluorescent OPD to be oxidized and produce 2,3-diaminophenazine (DAP), resulting in intense yellow fluorescence emission at 555 nm. DAP can quench the B-CDs based on inner filter effect (IFE), leading to a decrease in their fluorescence intensity at 435 nm. Because glucose oxidase may catalyze the oxidation of glucose to produce H2O2, this approach can also be used to detect glucose. The unique triangular structure leads to the easy etching of the edge and tip of Ag NPRs by H2O2 into Ag+ ions, allowing for the high sensitivity of detection of H2O2 and glucose with limit of detection (LOD) of 0.12 μM and 0.6 μM, respectively. Furthermore, with the increase of the concentrations of H2O2 and glucose, a visible color shift from blue to yellow-green occurs, which can be detected using a smartphone's color recognition application that captures the RGB channel values of the image. Real-time and on-spot detection of H2O2 and glucose were achieved based on smartphone sensing platform, presenting vast potential for applications in various fields.

Detection of ascorbic acid by persistent luminescent nanoparticles based on CoOOH nanosheets modification.

Persistent luminescent nanomaterials (PLNPs) Zn0.8Ga2O4: Cr3+, Zr3+ with high brightness and good dispersion were prepared by hydrothermal method. The PLNPs were used as luminescent units, and CoOOH nanosheets were used as quenching agents. Based on the fluorescence internal filtering effect, the luminescence of PLNPs were effectively quenched by CoOOH modification on the surface of PLNPs. However, the introduction of ascorbic acid (AA) restored the luminescence of PLNPs and successfully achieved highly sensitive and selective detection of AA. This was due to a selective redox reaction between CoOOH and AA, in which CoOOH was reduced to Co2+. The degree of luminescence recovery of PLNPs showed a good linear relationship with AA concentration in the range 5-250 µM, with a detection limit of 0.72 µM. Therecovery of actualspikedsamples were 97.9-102.2%. This method isexpected to provide reference for the study of other redox substances in biological systems.

Determination of low carbon aldehydes and ketones in cigarette smoke by MXene membrane enrichment-liquid chromatography

Low carbon aldehydes and ketones are typical substances harmful to human body produced during cigarette smoking. Their contents in cigarette smoke are important indicators for evaluating its toxicity and the filtration effect of cigarette filter tips, which provides important guidance for its rational design. In this work, MXene membrane with unique lamellar structure was synthesized and loaded onto glass fiber filters to achieve effective enrichment of low carbon aldehydes and ketones. Compared to commercial Cambridge filters, the MXene-loaded filters exhibited higher extraction efficiency towards low-carbon aldehydes and ketones, making viable the detection of butyraldehyde, which was not detected by that enriched with Cambridge filters. Therefore, a MXene-based membrane enrichment-HPLC method was developed for the determination of low-carbon aldehydes and ketones in cigarette smoke with detection limits ranging from 0.133 μg/mL to 0.285 μg/mL. The applicability of the method was verified by analyzing three different types of filter cigarettes with the concentration in the range of 0.5–140 μg/branch for all the analytes, which were in good agreement with the manufacturer's results. The method is accurate and sensitive, and can be used for the quantitative determination of low carbon aldehydes and ketones in cigarette smoke.

Fluorescent Carbon Nitride Nanoparticles for Picric Acid Sensing.

Detection of nitroaromatic explosives is essential in the area of environmental safety. Fluorescent carbon nitride nanoparticles is a promising material for this purpose. Herein, we have prepared fluorescent carbon nitride nanoparticles (CNNPs) by one step thermal treatment of formamide. These fluorescent CNNPs is sensitive towards picric acid (PA) than other analytes both in aqueous medium and on test paper which is witnessed by fluorescence quenching based on inner filter effect (IFE). The PA detection with the fluorescent CNNPs is observed in the concentration ranges, 0 µM to 60 µM with linear range of 10 nM to 25 µM. The minimum detection limit in aqueous medium and solid phase are determined to be 26.20 nM and 10 µM respectively. Finally, the fluorescent CNNPs is applied for detection of PA in real water samples. The recoveries are in the ranges from 99.54 to 116.35% with relative standard deviation less than 3.85%. This proposed fluorescent method can act as suitable analytical technique to monitored PA concentration in water samples.

Resource utilization of sewage sludge as a nitrogen self-doped carbon quantum dot for specific detection of Fe3+ and Hg2+

With the widespread application of sewage biological treatment technology, a large amount of sewage sludge is generated during the sewage treatment process, which not only poses a threat to the environment but also results in wastage of C and N resources. In this study, the nitrogen self-doped fluorescent carbon dots (N-CDs) with an average particle size of 3.43 nm were synthesized green through a two-stage hydrothermal method. It was found that N-CDs can detect Fe3+ through internal filtration effect (IFE), with a linear detection range of 0–250 μM and a detection limit of 2.207 μM. Furthermore, N-CDs can also serve as a “turn off–on” probe for monitoring Hg2+, with a linear detection range of 2–10 μM and a detection limit of 0.989 μM. Interestingly, oxygen-containing groups were shown to be sensitive to Hg2+, which has been demonstrated for the first time. Moreover, the practical application of N-CDs as a double ion sensor in the detection of Fe3+ and Hg2+ has achieved good results for real power plant wastewater.

Smartphone-based sensing and in vivo and in vitro imaging of Mn(VII) based on nitrogen-doped red fluorescent carbon dots.

Smartphone-assisted visual assay platform provides novel insight for the real-time in-field quantitation of intended analytes in resource-insufficient areas. Herein, nitrogen-doped red fluorescent (FL) carbon dots (R-CDs) were developed for the timely on-site quantitation of Mn(VII) using the smartphone-assisted assay platform. R-CDs, possessing a desirable bright red FL at 616 nm under a 470 nm excitation, were fabricated through hydrothermal treatment adopting passion fruit and neutral red as precursors. Interestingly, bright red FL at 616 nm are gradually quenched upon introducing Mn(VII) based on the inner filter effect, concurrently accompanying with significant FL color variation from bright red to dark red. Inspired by the above-mentioned phenomena, hue-saturation-values (HSV) of real-time captured images could be precisely quantified through a color recognition APP within the smartphone, of which the V/S values could be employed to quantify Mn(VII) with a linear range of 50-400 μM. Furthermore, confocal fluorescence imaging of HeLa cells and zebrafish larvae demonstrates that R-CDs could be employed for the visual determination of Mn(VII) in vivo and in vitro, illustrating that R-CDs possess powerful practical application prospect in biosystem.

Research on Filtering Algorithm of Vehicle Dynamic Weighing Signal

This study analyzes the advantages and disadvantages of filtering algorithms for dynamic weighing signals. Highway road surface has road surface unevenness and other influencing factors. The body vibration of the vehicle driving process produces a certain amount of interference signals collected by the load cell to form noise signals. In addition, piezoelectric sensors and amplification circuits introduce a large amount of electrical noise. These noise signals are non-smooth, nonlinear, and have other characteristics. We study the filtering effects of moving average (MA), wavelet transform (WT), and variational mode decomposition (VMD) filtering algorithms on axle weight signals and evaluate the performance of the filtering algorithms through the Root Mean Square Error (RMSE), signal-to-noise ratio (SNR), and Normalized Correlation Coefficient (NCC). The comprehensive analysis shows that the variational modal decomposition filtering algorithm is more advantageous for axial weight signal processing. The design of the axle weight signal noise filtering algorithm is of great significance for improving the accuracy of the overall dynamic weighing system of the vehicle.

Bioinspired Carbon Dots-Based Fluorescent Sensor for the Selective Determination of a Potent Anti-Inflammatory Drug in the Presence of Its Photodegradation Products.

Herein, we synthesized biogenic carbon dots (CDs) with blue-shifted maximum excitation (λex/λem of 320/404 nm) from largely wasted tangerine seeds for the first time via a one-step hydrothermal method. The biogenic CDs exhibit a maximum excitation wavelength that overlaps with the absorption spectrum of ketorolac tromethamine (KETO) at 320 nm. The developed CDs serve as a turn-off fluorescent probe via an inner filter effect (IFE) quenching mechanism. The resulting CDs have high quantum yield (QY) (39% ± 2.89%, n = 5) and exhibited great performance toward KETO over a concentration range of 0.50-16.00 μg/mL with a limit of detection (LOD) = 0.17 μg/mL. The nanoprobe achieved a high % recovery in assaying KETO in tablet dosage form and had not been significantly affected by various interferents including co-formulated and co-administered drugs. The nanoprobe shows selectivity toward KETO, even in the presence of its photocatalytic degradation products. It can effectively investigate the elimination of KETO from aquatic systems and test its stability in pharmaceutical preparations. The developed nanoprobe underwent a comprehensive evaluation of its environmental impact using analytical eco-scale (AES), complex green analytical procedure index (Complex GAPI), and the Analytical GREEnness calculator (AGREE). The sustainability of the developed nano sensor was assessed and compared to the reported metal-based quantum dots probe for KETO using the innovative RGB 12 model, considering 12 white analytical chemistry (WAC) perspectives.

A dual-signal triple-readout optical sensing platform for α-glucosidase and β-glucosidase activity monitoring and inhibitor screening based on luminescent covalent organic framework

BackgroundAs promising biomarkers of diabetes, α-glucosidase (α-Glu) and β-glucosidase (β-Glu) play a crucial role in the diagnosis and management of diseases. However, there is a scarcity of techniques available for simultaneously and sensitively detecting both enzymes. What's more, most of the approaches for detecting α-Glu and β-Glu rely on a single-mode readout, which can be affected by multiple factors leading to inaccurate results. Hence, the simultaneous detection of the activity levels of both enzymes in a single sample utilizing multiple-readout sensing approaches is highly attractive. ResultsIn this work, we constructed a facile sensing platform for the simultaneous determination of α-Glu and β-Glu by utilizing a luminescent covalent organic framework (COF) as a fluorescent indicator. The enzymatic hydrolysis product common to both enzymes, p-nitrophenol (PNP), was found to affect the fluorometric signal through an inner filter effect on COF, enhance the colorimetric response by intensifying the absorption peak at 400 nm, and induce changes in RGB values when analyzed using a smartphone-based color recognition application. By combining fluorometric/colorimetric measurements with smartphone-assisted RGB mode, we achieved sensitive and accurate quantification of α-Glu and β-Glu. The limits of detection for α-Glu were determined to be 0.8, 1.22, and 1.85 U/L, respectively. Similarly, the limits of detection for β-Glu were 0.16, 0.42, and 0.53 U/L, respectively. SignificanceApplication of the proposed sensing platform to clinical serum samples revealed significant differences in the two enzymes between healthy people and diabetic patients. Additionally, the proposed sensing method was successfully applied for the screening of α-Glu inhibitors and β-Glu inhibitors, demonstrating its viability and prospective applications in the clinical management of diabetes as well as the discovery of antidiabetic medications.