Corrosion behavior, antibacterial properties and in vitro and in vivo biocompatibility of biodegradable Zn-5Cu-xMg alloy for bone-implant applications.

Reasonable optimization of degradation rate, antibacterial performance and biocompatibility is crucial for the development of biodegradable zinc alloy medical implant devices with antibacterial properties. In this study, various amounts of Mg elements were incorporated into Zn5Cu alloy to modulate the degradation rate, antibacterial properties and biocompatibility. The effects of Mg contents on the microstructure, corrosion behavior, antibacterial properties and biocompatibility of Zn-5Cu-xMg alloy were extensively investigated. The results revealed that with an increase of Mg content, the amount of Mg2Zn11 phase increased and its galvanic effect with the Zn matrix was enhanced, which accelerated the corrosion process and led to higher corrosion rate and high degradation rate of the alloy. Additionally, there was an increased release of Mg2+ and Zn2+ ions from the alloy which imparted excellent resistance against Escherichia coli and Staphylococcus aureus bacteria and improved biocompatibility, subcutaneous antibacterial and immune microenvironment regulation properties. Zn-5Cu-2 Mg exhibited superior antibacterial ability, cell compatibility, proliferation effect, subcutaneous antibacterial and immune microenvironment regulation performances, which can work as a promising candidate of biodegradable antibacterial medical implants.

Efficient cocrystal coformer screening based on a Machine learning Strategy: A case study for the preparation of imatinib cocrystal with enhanced physicochemical properties.

Cocrystal engineering, which involves the self-assembly of two or more components into a solid-state supramolecular structure through non-covalent interactions, has emerged as a promising approach to tailor the physicochemical properties of active pharmaceutical ingredient (API). Efficient coformer screening for cocrystal remains a challenge. Herein, a prediction strategy based on machine learning algorithms was employed to predict cocrystal formation and seven reliable models with accuracy over 0.890 were successfully constructed. Imatinib was selected as the model drug and the models established were applied to screen 31 potential coformers. Experimental verification results indicated RF-8 is the optimal model among seven models with an accuracy of 0.839. When the seven models were combined for coformer screening of Imatinib, the combinational model achieved an accuracy of 0.903, and eight new solid forms were observed and characterized. Benefiting from intermolecular interactions, the obtained multicomponent crystals displayed enhanced physicochemical properties. Dissolution and solubility experiments showed the prepared multicomponent crystals had higher cumulative dissolution rate and remarkably improved the solubility of imatinib, and IM-MC exhibited comparable solubility to Imatinib mesylate α form. Stability test and cytotoxicity results showed that multicomponent crystals exhibited excellent stability and the drug-drug cocrystal IM-5F exhibited higher cytotoxicity than pure API.

Fertilization intensities at the buffer zones of ponds regulate nitrogen and phosphorus pollution in an agricultural watershed.

The sudden increase in water nutrients caused by environmental factors have always been a focus of attention for ecologists. Fertilizer inputs with spatio-temporal characteristics are the main contributors to water pollution in agricultural watersheds. However, there are few studies on the thresholds of nitrogen (N) and phosphorus (P) fertilization rates that affect the abrupt deterioration of water quality. This study aims to investigate 28 ponds in Central China in 2019 to reveal the relationships of basal and topdressing fertilization intensities in surrounding agricultural land with pond water N and P concentrations, including total N (TN), nitrate (NO3--N), ammonium (NH4+-N), total P (TP), and dissolved P (DP). Abrupt change analysis was used to determine the thresholds of fertilization intensities causing sharp increases in the pond water N and P concentrations. Generally, the observed pond water N and P concentrations during the high-runoff period were higher than those during the low-runoff period. The TN, NO3--N, TP, DP concentrations showed stronger positive correlations with topdressing intensities, while the NH4+-N concentrations exhibited a higher positive correlation with basal intensities. On the other hand, the NO3--N concentrations had a significant positive correlation with the topdressing N, basal N, and catchment slope interactions. Significant negative correlations were observed between all water quality parameters and pond area. Spatial scale analysis indicated that fertilization practices at the 50 m and 100 m buffer zone scales exhibited greater independent effects on the variations in the N and P concentrations than those at the catchment scale. The thresholds analysis results of fertilization intensities indicated that pond water N concentrations increased sharply when topdressing and basal N intensities exceeded 163 and 115 kg/ha at the 100 and 50 m buffer zone scales, respectively. Similarly, pond water P concentrations rose significantly when topdressing and basal P intensities exceeded 117 and 78 kg/ha at the 50 m buffer zone scale, respectively. These findings suggest that fertilization management should incorporate thresholds and spatio-temporal scales to effectively mitigate pond water pollution.

Recent Advances in Co-Former Screening and Formation Prediction of Multicomponent Solid Forms of Low Molecular Weight Drugs.

Multicomponent solid forms of low molecular weight drugs, such as co-crystals, salts, and co-amorphous systems, are a result of the combination of an active pharmaceutical ingredient (API) with a pharmaceutically acceptable co-former. These solid forms can enhance the physicochemical and pharmacokinetic properties of APIs, making them increasingly interesting and important in recent decades. Nevertheless, predicting the formation of API multicomponent solid forms in the early stages of formulation development can be challenging, as it often requires significant time and resources. To address this, empirical and computational methods have been developed to help screen for potential co-formers more efficiently and accurately, thus reducing the number of laboratory experiments needed. This review provides a comprehensive overview of current screening and prediction methods for the formation of API multicomponent solid forms, covering both crystalline states (co-crystals and salts) and amorphous forms (co-amorphous). Furthermore, it discusses recent advances and emerging trends in prediction methods, with a particular focus on artificial intelligence.

Realizing consumers' existential dreams via product marketing and mixed reality: a perspective based on affective neuroscience theories.

In an era of swift societal changes and escalating consumerism, this paper presents an exploration of an innovative approach that integrates product marketing strategies, mixed reality (MR) technology, and affective neuroscience theories to actualize consumers' existential dreams. MR, with its unique capacity to blend the virtual and real worlds, can enhance the consumer experience by creating immersive, personalized environments that resonate with consumers' existential aspirations. Insights from affective neuroscience, specifically the brain's processing of emotions, guide the development of emotionally engaging marketing strategies, which strengthen the connection between consumers, products, and brands. These integrated strategies not only present a novel blueprint for companies to deepen consumer engagement but also promise more fulfilling and meaningful consumer experiences. Moreover, this approach contributes to societal well-being and prosperity, marking a significant stride in the field of marketing.

Recent Advances in Zein-Based Nanocarriers for Precise Cancer Therapy.

Cancer has emerged as a leading cause of death worldwide. However, the pursuit of precise cancer therapy and high-efficiency delivery of antitumor drugs remains an enormous obstacle. The major challenge is the lack of a smart drug delivery system with the advantages of biodegradability, biocompatibility, stability, targeting and response release. Zein, a plant-based protein, possesses a unique self-assembly ability to encapsulate anticancer drugs directly or indirectly. Using zein as a nanotherapeutic pharmaceutic preparation can protect anticancer drugs from harsh environments, such as sunlight, stomach acid and pepsin. Moreover, the surface functionalization of zein is easily realized, which can endow it with targeting and stimulus-responsive release capacity. Hence, zein is an ideal nanocarrier for the precise delivery of anticancer drugs. Combined with our previous research experiences, we attempt to review the current state of the preparation of zein-based nanocarriers for anticancer drug delivery. The challenges, solutions and development trends of zein-based nanocarriers for precise cancer therapy are discussed. This review will provide a guideline for precise cancer therapy in the future.

The Portevin-Le Chatelier Effect of Cu-2.0Be Alloy during Hot Compression.

The Portevin-Le Chatelier effect of Cu-2.0Be alloy was investigated using hot isothermal compression at varying strain rates (0.01-10 s-1) and temperature (903-1063 K). An Arrhenius-type constitutive equation was developed, and the average activation was determined. Both strain-rate-sensitive and temperature-sensitive serrations were identified. The stress-strain curve exhibited three types of serrations: type A at high strain rates, type B (mixed A + B) at medium strain rates, and type C at low strain rates. The serration mechanism is mainly affected by the interaction between the velocity of solute atom diffusion and movable dislocations. As the strain rate increases, the dislocations outpace the diffusion speed of the solute atoms, limiting their ability to effectively pin the dislocations, resulting in lower dislocation density and serration amplitude. Moreover, the dynamic phase transformation triggers the formation of nanoscale dispersive ß phases, which impede dislocation and cause a rapid increase in the effective stress required for unpinning, leading to the formation of mixed A + B serrations at 1 s-1.

The effects of continuous straw returning strategies on SOC balance upon fresh straw incorporation.

Continuous straw returning is widely encouraged for augmenting soil organic carbon (SOC) in arable lands. However, the magnitude of changes in net SOC related to native SOC mineralization and new SOC development upon fresh straw incorporation remains elusive, particularly in soils after continuous straw returning with different strategies. To address this, soil that had undergone nine years of straw returning with different strategies (NS, non-straw returning; DS, direct straw returning; IS, indirect straw returning) was incubated with fresh 13C-labeled straw for 45 days. Fresh straw incorporation stimulated native SOC-derived CO2 emission in DS soil, which in turn promoted straw-derived CO2 emission in IS soil. Overall, the amounts of newly developed SOC from straw (2.41-2.59 g C/kg soil) overcompensated for the native SOC losses (0.91-1.37 g C/kg soil) by mineralization, and led to net C sequestration in all treatments. No obvious difference was found in the amounts of SOC sequestrated from straw between the DS and NS soils, while the amount of native SOC mineralization increased by 40-50% in the DS soil relative to other treatments, thus resulting in lower net C sequestration in the DS soil (1.21 g C/kg soil) than IS and NS soil (1.43 and 1.65 g C/kg for IS and NS soil, respectively). Spearman's correlation analyses indicated a significant (p < 0.01) and positive correlation between SOC contents and native soil C mineralization, while the soil microbial index played a greater role in influencing fresh straw sequestration (p < 0.01). In conclusion, the DS soil showed a weaker effect on SOC sequestration than IS after 9 years of practices, upon fresh straw incorporation. This difference may be attributed to the magnitude of native SOC mineralization in the soil. Besides the straw-C input rate, results emphasize that native soil C protection should be also considered in long-term SOC sequestration practices.

Co-immobilization of ß-xylosidase and endoxylanase on zirconium based metal-organic frameworks for improving xylosidase activity at high temperature and in acetone.

Improving the activity of ß-xylosidase at high temperature and organic solvents is important for the conversion of xylan, phytochemicals and some hydroxyl-containing substances to produce xylose and bioactive substances. In this study, a ß-xylosidase R333H and an endoxylanase were simultaneously co-immobilized on the metal-organic framework UiO-66-NH2. Compared with the single R333H immobilization system, the co-immobilization enhanced the activity of R333H at high temperature and high concentration of acetone, and the relative activities at 95 °C and 50% acetone solution were >95%. The Km value of co-immobilized R333H towards p-Nitrophenyl-ß-D-xylopyranoside (pNPX) shifted from 2.04 to 0.94 mM, which indicated the enhanced affinity towards pNPX. After 5 cycles, the relative activities of the co-immobilized enzymes towards pNPX and corncob xylan were 52% and 70% respectively, and the accumulated amount of reducing sugars obtained by co-immobilized enzymes degrading corncob xylan in 30% (v/v) acetone solution was 1.7 times than that with no acetone.

Gastrointestinal pH-Sensitive Pickering Emulsions Stabilized by Zein Nanoparticles Coated with Bioactive Glycyrrhizic Acid for Improving Oral Bioaccessibility of Curcumin.

Pickering emulsions have received considerable attention for their stability and functionality. Environmentally responsive Pickering emulsions could be used as vehicles for oral administration. However, challenges still exist, such as nonbiocompatibility of emulsifier and mismatched response behavior in the gastrointestinal environment. In this study, a strategy was proposed that bioactive saponin glycyrrhizic acid (GA) was used as a pH-responsive substance to functionalize zein nanoparticles, and tannic acid (TA) was used as a primer for cross-linking GA and zein nanoparticles. The Pickering emulsions fabricated by zein/TA/GA nanoparticles (ZTGs) exhibited excellent stability at acid conditions while slowly demulsifying at neutral conditions, which can be further used as an intestine-targeted delivery system. Curcumin was encapsulated into ZTG-stabilized Pickering emulsions, and the encapsulation efficiency results suggested that the presence of GA coating remarkably facilitated the encapsulation of curcumin. An in vitro digestion study suggested that ZTGs provided protection for emulsions from pepsin hydrolysis and exhibited higher free fatty acid release as well as higher bioaccessibility of curcumin during simulated intestine digestion. This study provides an effective strategy to prepare pH-responsive Pickering emulsions for improving the oral bioaccessibility of hydrophobic nutraceuticals.

Functional System Based on Glycyrrhizic Acid Supramolecular Hydrogel: Toward Polymorph Control, Stabilization, and Controlled Release.

Developments of a drug delivery system (DDS) based on a natural supramolecular hydrogel have been of wide interest due to its biocompatibility, efficacy, and adjustable performance. However, a simple and efficient design of functional hydrogel DDS based on the templated interplay of gelator and model drug is still a challenge. In this work, natural glycyrrhetinic acid (GA) gel was selected as a carrier to encapsulate the model drug pyrazinamide (PZA). It was found that the carboxyl-amide interaction at the interface of gel-drug achieved polymorph control, stabilization, and pH-responsive release. Powder X-ray diffraction confirmed that the metastable γ form of PZA was obtained from the GA gel. Spectral analysis and molecular dynamics simulation showed that the protonation at the amide-O promoted the discretization of PZA molecules in solution, resulting in the polymorphism. Furthermore, the gel-drug interplay increased the stability of the γ form significantly from 2 days to 3 months by in situ encapsulation in the GA gel. In vitro release study indicated that the GA gel achieved targeted control release of PZA due to the pH-responsiveness property of GA. This work provides a promising option for hydrogel-based DDS design combined with polymorph control and stabilization.

Creatine ameliorates high-fat diet-induced obesity by regulation of lipolysis and lipophagy in brown adipose tissue and liver.

Diet-induced obesity in mice and humans is commonly associated with an imbalance between energy intake and expenditure. Reportedly, creatine can enhance energy expenditure in brown adipose tissue and reduce hepatic triglycerides accumulation; however, the molecular mechanism underlying the role of exogenous creatine supplementation in regulating lipid droplet mobilization remains elusive. Herein, we employed a high-fat diet (HFD)- induced mouse model to investigate the role of creatine in regulating lipolysis and lipophagy in brown adipose tissue and the liver. Exogenous creatine supplementation ameliorated HFD-induced obesity, increased insulin sensitivity and improved glucose homeostasis. Creatine supplementation enhanced the expression of uncoupling protein 1 (UCP1), cell death-inducing DNA fragmentation factor alpha-like effector A (CIDEA), and other brown adipose tissue-specific thermogenic genes Cpt1a, Gyk, and Pgc1ß in brown adipose tissue. Furthermore, creatine inhibited the expression of CIDEA, which promotes hepatic lipid accumulation. Creatine stimulated the expression of triglyceride lipase adipose triglyceride lipase, and phospho-hormone-sensitive lipase (HSL) induced increased lipolysis in brown adipose tissue and the liver. Meanwhile, reduced LC3B expression was accompanied by an increased level of p62 in HFD-fed mice, indicating diminished basal autophagy in brown adipose tissue and the liver; however, creatine enhanced P62/LC3B induced lipophagy in brown adipose tissue and the liver. Collectively, our results suggest that creatine may function as a brown adipose tissue activator to increase whole-body energy metabolism via coordinated lipolysis and lipophagy in brown adipose tissue and the liver.

Development of a Method for Fast Assessment of Protein Solubility Based on Ultrasonic Dispersion and Differential Centrifugation Technology.

Protein solubility is very important for protein crystallization, bioprocess development, and protein application. In this study, a method based on the stability of a protein dispersion system is proposed for fast assessment of protein solubility, which mainly involves ultrasonic dispersion, differential centrifugation, and spectral measurement (UDDCS) and curvature estimation. The appropriate ultrasonic time and centrifugal time were experimentally determined at first. The results show that the relationship between the standard deviation and the protein concentrations originally added accords with the modified exponential equation, and the corresponding concentration of the maximum curvature point is defined as the solubility of the protein. Lysozyme solubility data in NaCl aqueous solutions and zein solubility data in ethanol aqueous solutions are selected to verify the UDDCS method by comparing the data obtained by the UDDCS method and the results from references, and the results indicate that the UDDCS method is reliable, universal, and time-saving. Finally, measurements of zein solubility in NaOH solution and casein solubility in urea aqueous solution were conducted as test cases by the UDDCS method.

The psychology of the internet fraud victimization of older adults: A systematic review.

Criminals targeting and exploiting older adults in online environments are of great concern. This study systematically retrieved and analyzed articles on the psychological characteristics of older adult victims of online fraud. First, we found that there was no evidence that older adults were more prevalent than other individuals of other ages among online fraud victims, and current researchers have focused more on why older adults are easy targets for fraud (susceptibility to being cheated). Second, research on psychological factors of older adults' susceptibility to online fraud has mainly focused on cognitive function, trust traits, and other personality traits, such as social loneliness, the Big Five personality traits, and self-control. Among them, most researchers claim that the cyber-cheating of older adults may be due to a decline in their cognitive function. However, there has not been a consensus on how cognitive function and physical and mental conditions affect older people who are cheated. Third, techniques (i.e., methods and techniques used by fraudsters) and experience (i.e., familiarity with internet technology or fraud) may be related to the susceptibility of older adults to fraud, and these studies have also not yet generated a consensus supported by reliable data. Based on the above research uncertainties, we propose that fraud prevention and control strategies for older adults should be applied with caution.

Earthworms promote the transfer of 15N-urea to lettuce while limit appreciably increase 15N losing to environment.

Earthworm activities not only increase nitrogen (N) uptake by crops, but also lead to N losing to environment. Thus, the present study examined the transformation of 15N-labeled urea with and without earthworms (Metaphire guillelmi) in a soil-lettuce system. We evaluated lettuce 15N uptake, 15N losses including N2O emission, NH3 volatilization and leaching, as well as 15N remaining in soil. Results showed that 15N-urea uptakes by lettuce significantly increased from 33.07% to 42.72% with earthworm presence. However, little difference was found on the total amounts of leaching and gaseous losses (N2O emission and NH3 volatilization) from 15N-urea between the treatment with and without earthworms (4.04 and 5.38%, respectively). Most of the 15N-urea remained in the soil, accounting for 48.44% and 60.65% of the 15N-urea in soil with and without earthworm presence. We conclude that earthworms enhanced the transfer of 15N-urea to lettuce without appreciably increasing the 15N-urea loss from soil to the environment.

Effects of Surfactants on Zein Cast Films for Simultaneous Delivery of Two Hydrophilic Active Components.

In order to prepare edible films with outstanding antimicrobials and antioxidants utilized in applications of food and pharmaceutics, in this study, effects of surfactants on zein cast films for simultaneous delivery of lysozyme (LY) and ascorbic acid (AA) were investigated, where sodium alginate (SA), soy lecithin (SL), and Pluronic f-68 (PF-68) were selected as surfactants. FT-IR tests indicated that SL or PF-68 dramatically changed secondary structure of zein composite films, which heightened the irregularity of the composite film and inhibited LY crystallization. Mechanical tests showed that highly flexible films exhibiting elongations between 129% and 157% were obtained when adding PF-68. Compared with the film without emulsifier, zein film containing SL and PF-68 showed approximately 7.51 and 0.55 times lower initial release rates for LY and AA respectively, which significantly improved the controlled release and heightened the anti-microbial and anti-oxidant activities of the film. Finally, emulsified mechanisms of the surfactants in zein films were proposed.

Responses of Soil Microbial Traits to Ground Cover in Citrus Orchards in Central China.

A clear understanding of which factors play an important role in the development of the soil microbial community in orchards will benefit our understanding of ground cover impacts on soil nutrient cycling. Thus, in the present study, grass properties, soil properties, and soil microbial community structure were determined in a citrus orchard after 5 years of management with different types of ground cover (NG: natural grass, LP: monoculture of legumes, and NL: mixed culture of natural grasses and legumes) to evaluate how ground cover biomass and nitrogen-fixing ability drive soil physicochemical and microbial traits. Plant biomass carbon (BC) and nitrogen (BN) were significantly higher in LP and NL than NG and showed a significant (p < 0.01) positive relationship with soil total carbon (TC), NO3--N (NN), and dissolved organic carbon (DOC) content. In addition, the amount of biologically fixed nitrogen (FixN) showed a significant positive relationship with soil total nitrogen (TN) (p < 0.05) and NH4+-N (AN) content (p < 0.01). We also observed a difference in the soil microbial community structure between plots with and without legumes. The TC and BN were the most influential factors driving bacterial and fungal communities, respectively. Nevertheless, FixN explained less than 9% of the differences in soil bacterial and fungal communities. Our results suggest that grass biomass and FixN are the strong drivers of soil chemical properties, whereas ground cover and soil properties both contribute significantly to the soil microbial community structure.

Enzymatic Cascade Reactions Mediated by Highly Efficient Biomimetic Quasi Metal-Organic Frameworks.

The integration of chemo- and enzymatic catalysis for effective multistep cascades has presented critical challenges for decades. In this work, the biomimetic quasi NH2-MIL-101 (qNM) with highly efficient peroxidase-like activity was synthesized via a palmitic acid-induced strategy followed by pyrolysis. The effects of the amount of palmitic acid and calcination temperature on the synthesis of qNM were optimized. It was found that qNM was an excellent catalyst for oxidations of various peroxidase substrates, and a possible mechanism was proposed, i.e., the presence of FeII species in qNM was responsible for its excellent activity, which facilitated the transition between FeII and FeIII species to produce more hydroxyl radicals by H2O2 decomposition. The qNM served as the potential matrix for enzyme immobilization through a cross-linking method, and kinetic studies revealed that the catalytic efficiency (kcat/Km) for the immobilized GOx (23.7 mM-1 s-1) is comparable to that of free GOx (26.9 mM-1 s-1). The immobilized GOx also showed improved stability against high temperatures and organic solvents compared to free GOx, and analysis of the secondary structure of GOx indicated that the improved stability resulted from enzyme rigidity by the intense covalent linkage with qNM. Furthermore, qNM contributed its biomimetic activity to cooperate with a single enzyme (GOx) or two enzymes (ß-Gal and GOx) for the enzymatic cascade reactions. Compared with the mixture of each component in the solution, the combination of the single-enzyme system (GOx) or the two-enzyme system (ß-Gal and GOx) in qNM achieved 2.67-fold and 1.83-fold enhancements in the activity of catalytic cascades, respectively. This study provides new insights into the construction of effective and synergistic cascade reactions by integrating biomimetic MOF with natural enzyme, which holds potential for applications in biotechnology and ecofriendly and biomimetic catalysis.

Enhancing hemocompatibility and the performance of Au@silica nanoparticles by coating with cRGD functionalized zein.

Poor safety and effectiveness is an outstanding challenge in the preparation of drug delivery systems (DDS) for cancer treatment. The pursuit of the high curative effect will inevitably increase the risk of adverse side effects. Herein, a bio-safe DDS was constructed by combining the advantages of functional zein and Au doped mesoporous silica nanoparticles (Au@SiO2) to achieve chemo-photothermal therapy. The cRGD functionalized zein (cRGD-Zein) was coated on the surface of Au@SiO2 which effectively avoided premature leakage of paclitaxel and realized sustained drug release. Meanwhile, the high hemolysis rate (107%) of Au@SiO2 had been significantly reduced to 4%. The anti-hemolysis mechanism of functionalized zein was explored to give a deeper understanding of the interaction between nanoparticles and RBCs. The results showed that the functional zein would change the protein conformation during the interaction with Au@SiO2 to protect the RBCs from the damage of Au@SiO2. And the release rate of hemoglobin was limited by the size of RBCs membrane cracks with approximately 40 nm in width and 470 nm in length. The cell cytotoxicity and uptake assays showed that the prepared DDS exhibited low tumour cell viability (35%) and enhanced uptake performance (99.3%). This work suggested that the prepared nanoparticles could serve as a promising carrier to achieve safe and efficacious tumour therapy.

Paper-based analytical device for high-throughput monitoring tetracycline residue in milk.

A low-cost and portable paper-based analytical device has been developed for high throughput and on-site monitoring TC residue in milk through visualized colorimetric reaction. The filtration and concentration effect induced by the porous nature of paper contribute to strengthen the color intensity, leading to quantitative and sensitive detection of tetracycline reaching 1 ppm detection limit, with the linear range of 1-100 ppm both in water and milk samples. The applicability was demonstrated by detection of TC in 18 different types of real milk samples with good recovery ranging from 88% to 113%. Furthermore, the dynamic degradation behavior of tetracycline was monitored through the device. To the best of our knowledge, this is the first report of colorimetric detection of tetracycline in milk using the paper-based device. This simple, fast, cost-effective (~$0.50 per device) and equipment-free paper-based platform provides a promising tool for future application in food and environmental safety.