Reduced Reaction Time Research Articles

Synthesis of Two-Dimensional (Cu-S)n Metal-Organic Framework Nanosheets Applied as Peroxidase Mimics for Detection of Glutathione.

Facilely synthesized peroxidase-like nanozymes with high catalytic activity and stability may serve as effective biocatalysts. The present study synthesizes peroxidase-like nanozymes with multinuclear active sites using two-dimensional (2D) metal-organic framework (MOF) nanosheets and evaluates them for their practical applications. A simple method involving a one-pot bottom-up reflux reaction is developed for the mass synthesis of (Cu-S)n MOF 2D nanosheets, significantly increasing production quantity and reducing reaction time compared to traditional autoclave methods. The (Cu-S)n MOF 2D nanosheets with the unique coordination of Cu(I) stabilized in Cu-based MOFs demonstrate impressive activity in mimicking natural peroxidase. The active sites of the peroxidase-like activity of (Cu-S)n MOF 2D nanosheets were predominantly verified as Cu(I) rather than Cu(II) of other Cu-based MOFs. The cost-effective and long-term stability of (Cu-S)n MOF 2D nanosheets make them suitable for practical applications. Furthermore, the inhibition of the peroxidase-like activity of (Cu-S)n MOF nanosheets by glutathione (GSH) could provide a simple strategy for colorimetric detection of GSH against other amino acids. This work remarkably extends the utilization of (Cu-S)n MOF 2D nanosheets in biosensing, revealing the potential for 2D (Cu-S)n MOFs.

Microwave Assisted Greener and Eco-Friendly Approach for Synthesis of Functionalized 2-Arylbenzoxazoles, 2-Arylbenzothiazoles, and 2-Arylbenzimidazoles Using Waste Curd Water

Herein, we have designed a greener and efficient microwave-assisted route for the synthesis of functionalized 2-arylbenzoxazoles, 2-arylbenzothiazoles, and 2-arylbenzimidazoles. These compounds were produced through the condensation reaction involving 2-aminophenol, 2-aminothiophenol, and 1,2-phenylenediamine, respectively, with corresponding aldehydes. Remarkably, this reaction was conducted employing waste curd water as a catalytic solvent and under the influence of microwave radiation. Curd water, a liquid byproduct obtained from the coagulation process during cheese or yogurt production, was harnessed as catalytic solvent for the reaction. The application of emerging microwave-assisted chemistry techniques in combination with greener reaction media dramatically reduces reaction time as well as chemical waste. This investigation not only demonstrates a waste-to-wealth paradigm but also contributes to the mitigation of environmental waste.

Effects of lip and eye color on the emotion categorization of facial expressions

AbstractThis study examined whether people's ability to recognize facial expressions is affected by manipulating the color of their lips or eyes. Participants comprised 100 Chinese adolescents (mean age = 13.79 years, SD = 1.06). The stimuli consisted of happy, neutral, and sad facial expressions, which were manipulated to have different lip or eye colors. Participants reacted to the images by indicating their perceived emotion. Performance speed and accuracy were assessed during the experiment. Results indicated that for happy and neutral expressions, the use of color significantly reduced reaction times, while the accuracy remained unchanged. Conversely, for sad expressions, reaction time was not affected by color, but all color categories exhibited reduced accuracy.

The effect of acute high-intensity interval training and Tabata training on inhibitory control and cortical activation in young adults.

Physical exercise not only benefits peoples' health, but also improves their cognitive function. Although growing evidence suggests that high-intensity interval training (HIIT) is a time-efficient exercise regime that can improve inhibitory control performance by enhancing cortical activation in the prefrontal cortex, less is known about how Tabata training, a subset of HIIT that requires no equipment or facilities to perform, affects inhibitory control and cortical activation in young adults. Therefore, we aimed to reveal the effect of an acute bout of HIIT and Tabata training on inhibitory control and attempted to identify its potential neural substrates. Forty-two young adults (mean age: 19.36 ± 1.36 years; 21 females) performed the Stroop task and Simon task before and after acute HIIT, Tabata training, or a control session, and cortical hemodynamic changes in the prefrontal area were monitored by functional near-infrared spectroscopy (fNIRS) during the tasks. Both HIIT and Tabata interventions lasted for a total of 12 min. The HIIT participants performed ergometer cycling at their 80% maximal aerobic power at 90-100 rpm, and the Tabata participants performed a total of 8 intense activities, such as jumping jacks, high knees, and butt kickers, without using equipment or facilities, keeping the heart rate at 80-95% of their maximum heart rate. Participants in the control group watched a sport video while sedentary. Cognitive tasks data and fNIRS data were analyzed by repeated-measures three-way ANOVA. Our results indicated that both the HIIT and Tabata groups exhibited reduced reaction times after the intervention, and there were alterations in activation patterns in the dorsolateral and ventrolateral prefrontal cortices.

Liquid state properties and rapid solidification mechanism of Fe-Nd-B alloy investigated under space simulation conditions

The thermophysical properties of liquid Fe84Nd10B6 alloy from superheated to undercooled state were investigated by space simulation technology combined with ab initio molecular dynamics (AIMD) simulations. The liquid density at liquidus temperature and its temperature coefficient were determined as 7.17 g·cm−3 and 5.51 × 10−4 g·cm−3·K−1, while its liquid thermal expansion coefficient was measured as 7.69 × 10−5 K−1. The ratio of specific heat to emissivity decayed as a quadratic power function. Under electrostatic levitation (ESL) condition, even though the cooling rate of liquid alloy was only 23.6–35.3 K/s, a maximum 131 K undercooling was realized. As alloy undercooling rose, the grain size of primary α(Fe) dendrite was refined, whose volume fraction decreased from 26.2% to 22.0%. Meanwhile, the volume fraction of major peritectic τ1(Nd2Fe14B) phase was increased from 68.6% to 76.8%, which was accompanied by the reduction of peri-eutectoid τ2(Nd1.1Fe4B4) phase down to 1.2%. In the case of microgravity processing by drop tube, liquid undercooling and cooling rate respectively reached up to 260 K (0.16 TL) and 3.9 × 104 K/s for the falling alloy droplets. Instead of τ1 phase, the primary α(Fe) phase occupied the largest volume fraction of 49.7% in large alloy droplets. At enhanced undercooling and cooling rate, the peritectic τ1 phase only increased from 26.2% up to 43.5%, whereas those of α(Fe) and τ2 phases declined to 44.0% and 12.5%, respectively. It was found that the increase of liquid alloy undercooling promoted the peritectic transformation to some extent, but high cooling rate greatly restricted peritectic reaction by reducing reaction time. The coupled effect of liquid undercooling and cooling rate controlled the volume fraction of each phase in rapidly solidified microstructures.

Lessons learned from poor governance: A comparison of the EU strategies for exiting the crises of 2008 and 2020

This paper analyses the EU's strategy for recovering from the economic and social consequences of the pandemic, of which the NextGenerationEU temporary stimulus package forms part. That strategy is compared to the diametrically opposite approach taken by EU institutions in the crisis of 2008. The most significant elements and economic policy references adopted in the two cases are identified. The paradigm shift in economic policy is evident, and the errors that led to a double dip in European economies in the handling of the earlier crisis have been avoided. In spite of the better discretionary response, it is argued that there is a need for a permanent, amply endowed, well-designed European stabilisation mechanism free from complexes in regard to the mutualisation of debt, so as to simplify procedures and reduce reaction times in the face of further crises.

Fast pyrolysis kinetics of waste tires and its products studied by a wireless-powered thermo-balance

Fast pyrolysis is commonly used in industrial reactors to convert waste tires into fine chemicals and fuels. However, current thermogravimetric analyzers are facing limitations that prevent the acquisition of kinetic information. To better understand the reaction kinetics, we designed a novel thermo-balance device that was capable of in-situ weight measurement during rapid heating. The results showed that the reaction rate substantially increased, with significant reductions in reaction time and apparent activation energy compared to slow pyrolysis. The change of reaction mechanism from the reaction order model to the nucleation and growth model was responsible for the increase in the degradation rate. Fast pyrolysis led to the generation of more trimers of isoprene as primary pyrolytic volatiles, which we further supported through density functional theory calculations. The findings suggested that fast pyrolysis has a higher chance of overcoming the high energy barrier to form trimers of isoprene. This comprehensive and in-depth understanding of fast pyrolysis kinetics and product distribution could reveal a more realistic process of waste pyrolysis, which benefited the industry.

The Production of Ultra-Thin Polyethylene-Based Carbon Fibers out of an “Islands-in-the-Sea” (INS) Precursor

Carbon fibers (CF) and their composites (CC) are one of the world’s most promising and avant-garde high-performance materials, as they combine excellent mechanical characteristics with high weight reduction potential. Polyethylene (PE) is the perfect alternative precursor for CF as it combines widespread availability, low cost, high carbon content, and, most importantly, precursor fibers that can be produced via melt-spinning. PE-based CF production involves a challenging and time-consuming diffusion-limited chemical stabilization step. The work presented in this article tackles the challenge of reducing the chemical stabilization process time by converting a bicomponent island-in-the-sea fiber, consisting of PA6 as sea matrix and HDPE as island material, into an ultra-thin PE-precursor fiber. The produced precursor fiber is then successfully converted into an ultra-thin PE-based CF through sulfonation and subsequent carbonization in a continuous set-up. The resulting CF has a smooth surface with no observable surface defects and a filament diameter of around 3 µm. The successful conversion to ultra-thin CF is shown in both batch and continuous processes. Additionally, a reduction in sulfonation reaction time from 4 h to 3 h is achieved.

Microwave-Assisted Synthesis of Biologically Relevant Six-Membered N-Heterocycles

Abstract: One of the most efficient non-conventional heating methods is microwave irradiation. In organic synthesis, microwave irradiation has become a popular heating technique as it enhances product yields and purities, reduces reaction time from hours to minutes, and decreases unwanted side reactions. Microwave-assisted organic synthesis utilizes dielectric volumetric heating as an alternative activation method, which results in rapid and more selective transformations because of the uniform heat distribution. Heterocyclic compounds have a profound role in the drug discov-ery and development process along with their applications as agrochemicals, fungicides, herbi-cides, etc., making them the most prevalent form of biologically relevant molecules. Hence, enor-mous efforts have been made to flourish green routes for their high-yielding synthesis under mi-crowave irradiation as a sustainable tool. Among the different clinical applications, heterocyclic compounds have received considerable attention as anti-cancer agents. Heterocyclic moieties have always been core parts of the development of anti-cancer drugs, including market-selling drugs, i.e., 5-fluorouracil, doxorubicin, methotrexate, daunorubicin, etc., and natural alkaloids, such as vinblastine and vincristine. In this review, we focus on the developments in the microwave-assisted synthesis of heterocycles and the anti-cancer activities of particular heterocycles.

Microwave-assisted Synthesis of Heterocycles and their Anti-cancer Activities

Abstract: One of the most efficient non-conventional heating methods is microwave irradiation. In organic synthesis, microwave irradiation has become a popular heating technique as it enhances product yields and purities, reduces reaction time from hours to minutes, and decreases unwanted side reactions. Microwave-assisted organic synthesis utilizes dielectric volumetric heating as an alternative activation method, which results in rapid and more selective transformations because of the uniform heat distribution. Heterocyclic compounds have a profound role in the drug discovery and development process along with their applications as agrochemicals, fungicides, herbicides, etc., making them the most prevalent form of biologically relevant molecules. Hence, enormous efforts have been made to flourish green routes for their high-yielding synthesis under microwave irradiation as a sustainable tool. Among the different clinical applications, heterocyclic compounds have received considerable attention as anti-cancer agents. Heterocyclic moieties have always been core parts of the development of anti-cancer drugs, including market-selling drugs, i.e., 5-fluoroura-cil, doxorubicin, methotrexate, daunorubicin, etc., and natural alkaloids, such as vinblastine and vincristine. In this review, we focus on the developments in the microwave-assisted synthesis of heterocycles and the anti-cancer activities of particular heterocycles.

Microwave-assisted Synthesis of Bioactive Six-membered O-heterocycles

Abstract: Microwave radiation has been utilised since the late 1970s as an alternative thermal energy source for chemical reactions. Initially used in inorganic chemistry, its potential for organic chemistry was revealed in 1986. Convertion of electromagnetic energy into heat, with frequencies ranging from 0.3-300 GHz using microwave irradi-ation, is an efficient heating method. The microwave heating method has significant potential for industrial processes, reducing reaction times and enhancing yields and se-lectivity. It finds applications in peptide and organic synthesis, materials science, pol-ymer chemistry, biochemical processes, and nanotechnology. Microwave-assisted or-ganic synthesis is environmentally friendly and beneficial for producing bioactive het-erocyclic compounds. Oxygen-containing heterocycles are abundant and possess vari-ous biological functions, making them essential for developing new drugs. Microwave technology facilitates the synthesis of these compounds, including bioactive six-mem-bered o-heterocycles such as pyrones, oxazolones, furanones, oxetanes, oxazoli-dinones, and dioxetanes. By utilizing modern organic transformations, microwave-as-sisted chemistry enhances the efficiency of synthetic processes, leading to the discovery of more beneficial molecules. The review provides an up-to-date analysis of the syn-thesis and medicinal properties of O-heterocycles, emphasizing the strengths and needs of this field. It guides researchers, facilitating microwave-assisted green synthesis re-actions and offering a flexible platform for forming bioactive heterocyclic rings.

Infusion of Magnetic Nanocatalyst to Microwave Propped Synthesis of Bioactive Azaheterocycles

Abstract: Microwave-assisted synthesis is a powerful tool in organic chemistry, providing a rapid and efficient method for the synthesis of bioactive heterocycles. The application of micro-waves significantly reduces reaction times and increases percentage yields with high purity of the final product. To make the synthetic protocol greener, the application of the magnetic nanocata-lyst is a rapidly growing area of interest nowadays. Magnetic nanocatalyst, with its unique fea-tures like magnetic separable facile recovery from the reaction media heterogeneously, makes the overall synthetic strategy cleaner, faster, and cost-effective. Aiming this, in the present review, we will focus on the infusion of Magnetic nanocatalyst to microwave-assisted synthesis of vari-ous classes of azaheterocyclic compounds, including pyridines, pyrimidines, quinolines, and ben-zimidazoles. The synthetic methodologies involved in the preparation of these heterocycles are highlighted, along with their biological activities. Furthermore, in this review, the most recent and advanced strategies to incorporate nanocatalysts in the microwave-assisted synthesis of nat-ural products containing azaheterocyclic moieties in drug discovery programs are elucidated in detail, along with the incoming future scope and challenges.

Conventional Versus Microwave Induced Synthesis and Biological Evolution of Coumarin Substituted Thioaryl Pyrazolyl Pyrazoline

Aim: This is a comparative study of some new coumarin substituted thioaryl pyrazolyl pyrazoline. Methods: The target compounds were synthesized using both conventional as well as microwave irradiation by reaction of coumarin chalcones with different substituted hydrazine hydrates and aryl hydrazines to give the resultant pyrazoline derivatives. Microwave reaction, enhanced or-ganic reactions, and reduced reaction time led to better yields and selectivity than conventional methods. Results: The obtained compounds were characterized by different spectroscopic analysis includ-ing IR, 1H-NMR, 13C-NMR, mass spectroscopy and elemental-analysis and evaluated for their antimicrobial screening against a representative panel of bacteria (Bacillus subtilis, Staphylococ-cus aureus, Escherichia coli, Salmonella typhi) and fungi (Aspergillus niger, Candida albicans). Conclusion: In the present study, we have synthesized coumarin pyrazoline derivatives clubbed with benzofuran pyrazole via both conventional and microwave irradiation and also subjected to antibacterial and antifungal studies. Synthesis of target compounds by the microwave irradiation enhanced reaction rate and reduced reaction time led to better yields and selectivity than conven-tional methods. The study of antibacterial and antifungal activities revealed that all the com-pounds exhibited reasonable to excellent activities against the pathogenic strains.

Synthesis of Copper/Sulfur Co-Doped TiO2-Carbon Nanofibers as Catalysts for H2 Production via NaBH4 Hydrolysis

Copper/sulfur co-doped titanium dioxide-carbon nanofibers (Cu,S-codoped TiO2 NPs, decorated-CNFs) catalysts were synthesized using the electrospinning process to produce composite nanofibers (NFs). These composite NFs were utilized for the hydrolysis of sodium borohydride (SBH) to generate hydrogen gas (H2), taking advantage of their catalytic properties. The experimental results demonstrated that using 100 mg of composite NFs yielded the highest catalytic activity for H2 production, generating 79 mL of H2 gas within 6 min at 25 °C and 1000 revolutions per minute (rpm) using 1 mmol of SBH. As the catalyst dosage was reduced from 100 mg to 75, 50, and 25 mg, the reaction time increased by 9, 13, and 18 min, respectively. Kinetic studies revealed that the reaction rate followed a first-order reaction, indicating a direct proportionality between the rate of reaction and the catalyst amount. Additionally, it was observed that the concentration of SBH had no influence on the reaction rate, suggesting a zero-order reaction. Increasing the reaction temperature resulted in a reduced reaction time. The activation energy was determined to be 26.16 kJ mol−1. The composite NFs maintained their superior performance over five iterations. These findings suggest that composite nanofibers have the potential to serve as a cost-effective alternative to expensive catalysts in hydrogen production.

Photoinduced Nitroarenes as Versatile Anaerobic Oxidants for Accessing Carbonyl and Imine Derivatives.

Herein, we report a protocol for the anaerobic oxidation of alcohols, amines, aldehydes, and imines promoted by photoexcited nitroarenes. Mechanistic studies support the idea that photoexcited nitroarenes undergo double hydrogen atom transfer (HAT) steps with alcohols and amines to provide the respective ketone and imine products. In the presence of aldehydes and imines, successive HAT and oxygen atom transfer (OAT) events occur to yield carboxylic acids and amides, respectively. This transformation is amenable to a continuous-photoflow setup, which led to reduced reaction times.

A case study for an eco-design of aluminum terephthalate metal-organic framework- MIL-53(Al) for CO2 and methane adsorption

Metal-organic frameworks (MOFs) are highly promising materials for environmental applications, including gas separation and CO2 capture. In the present study, a detailed comparison was first done on the hydrothermal production of MOF with terephthalic acid and aluminum- MIL-53(Al), synthesized with 24 h, 48 h, and 72 h time reaction. A comparative characterization between the different MIL-53(Al) syntheses was done by X-Ray Diffraction, scanning electron microscopy (SEM), thermogravimetric and infrared analysis, XPS spectroscopy, 13C MAS NMR and 27Al MAS NMR and CO2 Drifts, showing the maintenance of the structure and coordination environment for the 24 h synthesis. MIL-53(Al) synthesized at 24 h presented a very good surface area of 1711 m2 g−1 and adsorbed up to 13 mmol/g of CO2 and 4 mmol/g of CH4 at 25 bar and 348 K. Life cycle assessment (LCA) was first done to compare hydrothermal 72- and 24 h-MIL-53(Al), showing a reduction in electricity of 66.7%, and for freshwater ecotoxicity and ozone depletion, despite the great environmental burden of the solvents employed in the activation step. A greater reduction in environmental impacts was observed with the proposal of a method for 24 h-MIL-53(Al) synthesis which includes the aluminum recovery, the reduction of reaction time and volume of solvents, mainly observed for metal depletion, freshwater ecotoxicity, particulate matter formation, climate change, and human ecotoxicity, with reductions of 77.1%, 70.38%, 65%, 44.7% and 43.3%, respectively.

Synergistic effects of aerobic exercise and transcranial direct current stimulation on executive function and biomarkers in healthy young adults

ObjectiveThis research explored the combined effects of transcranial direct current stimulation (tDCS) and aerobic exercise (AE) on executive function and specific serum biomarkers in healthy adults. MethodsSixty healthy young adults were randomly assigned into tDCS+AE, tDCS only, or AE only groups. Interventions were carried out for 20 days. Executive functions were evaluated using tasks such as the 2,3-back task, the spatial working memory task, the Stroop test, T test, and hexagonal obstacle jump task. Serum biomarkers, including brain-derived neurotrophic factor (BDNF), malondialdehyde (MDA), superoxide dismutase (SOD), glutamate, glutathione peroxidase 4 (GPX4) and iron ion, were analyzed pre- and post-intervention. ResultsThe tDCS+AE group showed superior enhancements in executive function, evidenced by improved accuracy rates in 2,3-back tasks, better performance in the staircase task, and reduced reaction times in the incongruent reaction time of the Stroop task compared to other groups. Importantly, we found substantial changes in serum biomarkers: increased levels of BDNF and SOD, and decreased levels of MDA and glutamate in the tDCS+AE group. These changes were significantly different when compared with the tDCS and AE only groups. Notably, these alterations in serum biomarkers were correlated with improvements in executive function tasks, thus offering a potential physiological basis for the cognitive improvements witnessed. ConclusionThe combined tDCS and AE intervention effectively improved executive function in healthy young adults, with the improvements linked to changes in key serum biomarkers. The results emphasize the potential of combined tDCS and AE interventions in engaging multiple physiological pathways to enhance executive function.

Improved Process for the Synthesis of 3-(3-Trifluoromethylphenyl)propanal for More Sustainable Production of Cinacalcet HCl.

Cinacalcet (I), sold as hydrochloride salt, is a calcimimetic drug which has been approved for the treatment of secondary hyperparathyroidism in patients with chronic renal disease and for the treatment of hypercalcemia in patients with parathyroid carcinoma. Here, an improved method for the synthesis of 3-(3-trifluoromethylphenyl)propanal (II), a key intermediate for the preparation of I, is described. The protocol required a Mizoroki-Heck cross-coupling reaction between 1-bromo-3-(trifluoromethyl)benzene and acroleine diethyl acetal, catalyzed by Pd(OAc)2 in the presence of nBu4NOAc (tetrabutylammonium acetate), followed by the hydrogenation reaction of the crude mixture of products in a cascade process. Palladium species, at the end of the reaction, were efficiently recovered as Pd/Al2O3. The procedure was developed under conventional heating conditions as well as under microwave-assisted conditions. The obtained mixture of 1-(3,3-diethoxypropyl)-3-(trifluoromethyl)benzene (III), impure for ethyl 3-(3-trifluoromethylphenyl) propanoate (IV), was finally treated, under mild conditions, with potassium diisobutyl-tert-butoxyaluminum hydride (PDBBA) to obtain after hydrolysis 3-(3-trifluoromethylphenyl)propanal (II), in an excellent overall yield and very high purity. Microwave conditions permitted a reduction in reaction times without affecting selectivity and yield. The final API was obtained through reductive amination of (II) with (R)-(+)-1-(1-naphthyl)ethylamine (V) using a catalyst prepared by us with a very low content of precious metal.

Triple superphosphate modified by tin (II) chloride: As a reusable and efficient catalyst for the one-pot synthesis of xanthene and xanthenone derivatives under green conditions

A simple method was developed for preparing tin (II) chloride-triple superphosphate. The material was thoroughly characterized using various techniques, including transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) analysis. XRD analysis, BET, and SEM images indicated that the catalyst exhibited a crystalline structure and had particle sizes ranging from 21 to 23 nm. The catalytic performance was evaluated by conducting multicomponent one-pot condensation reactions. Specifically, the condensation of 2-naphthol with aldehydes and dimedone was conducted to produce 12-aryl(alkyl)-8,9,10,12 tetrahydrobenzo [a]xanthen-11-one derivatives, and the condensation of 2-naphthol with aldehydes was performed to synthesize 14-aryl(alkyl)-14H-dibenzo [a,j]xanthene derivatives. The acidic sites of the catalyst were determined using pyridine FTIR spectroscopy. The studies revealed that this catalyst system exhibited excellent performance, resulting in high product yields (88–96%) and reduced reaction times (12–20 min). The catalyst demonstrated high catalytic activity, good reusability, and a simple preparation method, thereby showing promise for potential industrial-scale applications.

Red emission upconversion of NaYF4: Yb3+/Er3+ nanoparticles: Rapid preparation via single-mode focused microwave method and their application in cell imaging

The red emission of upconversion nanoparticles (UCNPs) is located in an “optical window” range of the biological tissue, which has a promising prospect in biology application. In this work, novel red-emitting NaYF4:Yb3+/Er3+ UCNPs with CH3COO− modifications were synthesized by single-mode focused microwave method. The morphology, structure, and luminescence properties of as-prepared UCNPs were characterized. The results showed that single-mode focused microwave method was an effective approach to prepare hydrophilic and strongly red emission UCNPs within a drastically reduced reaction time (only 10 min) compared to the traditional methods. Importantly, we also demonstrated that the CH3COO− modified NaYF4:Yb3+/Er3+ UCNPs could be successfully applied for in vitro imaging of HeLa cells. This work not only provides a rapidly synthetic methodology for the preparation of red-emitting UCNPs but also offers an effective material for cancer cell imaging.