Fluorescence Detection System Research Articles

Carbon dots-based modularization fluorescent probe for simultaneous detection of Hg2+ and Cu2+ in water, cells and zebrafish

Modular assembly of carbon dots with organic luminescent small molecules can be devoted to picking up a predetermined fluorescent probe detection system for specific targets. In this work, the blue fluorescent carbon dots B-CDs were prepared by using sodium citrate and nitrogen-rich branched polyethyleneimine as precursors through a functional preservation strategy. A modularized, difunctional and ratiometric fluorescent probe B-CDs@RBH with dual-emission was dexterously prepared by simply blending B-CDs and rhodamine b-hydrazide for the detection of Hg2+ and Cu2+. B-CDs can be quenched by Hg2+ through static quenching, while Cu2+ can specifically open the lactam of rhodamine b-hydrazide to form rhodamine B through hydrolysis accompanied by a turn-on orange fluorescence. More interestingly, rhodamine B can absorb the fluorescence of B-CDs through fluorescence resonance energy transfer, resulting in a blue to orange fluorescence color change in the presence of Cu2+. B-CDs@RBH has a low detection limit of 17.79 nM and 4.19 nM for Hg2+ and Cu2+ respectively with a detection range of 0.1–5 μM, which was applied for the ratiometric fluorescence detection of Hg2+ and Cu2+ in cells and zebrafish, and achieved smartphone-assisted on-site water samples detection. The facile modular design of B-CDs@RBH fluorescent probe and convenient on-site detection application are of great benefit in further ascertaining the migration and transformation of heavy metals in biological and environmental samples.

A homogeneous capillary fluorescence imprinted nanozyme intelligent sensing platform for high sensitivity and visual detection of triclocarban

A homogeneous capillary fluorescence imprinted nanozyme intelligent sensor based on a dual-function metal-organic framework (NH2-MIL-101(Fe)) has been developed for highly sensitive and visual determination of triclocarban (TCC). The NH2-MIL-101(Fe) exhibited peroxidase-like properties to oxidize o-phenylenediamine to 2,3-diaminophenazine with yellow fluorescence (570 nm), which in turn suppresses the intrinsic fluorescence peak (445 nm) owing to the inner filter effect. The capillary fluorescence detection system was constructed by inhaling molecularly imprinted polymers solution with H2O2 and o-phenylenediamine into the capillary, which realized the homogeneous distribution of molecularly imprinted polymers in the capillary without the tedious operation of coating the inner wall of the capillary. TCC restored the fluorescence at 445 nm while quenching the fluorescence at 570 nm, resulting in a color shift from yellow to green to blue. The linear range of the fluorescence capillary imprinted sensor was determined to be 10 pM- 3.5 nM with the detection limit of 8.5 pM. The fluorescence color was converted to RGB value by using the smartphone to calculate TCC concentration with the detection limit of 9.8 pM, which provided a novel method for the determination of environmental pollutants with the microvolume consumption (18 μL/time).

XUV Fluorescence Detection of Laser-Cooled Stored Relativistic Ions

An improved moveable in vacuo XUV fluorescence detection system was employed for the laser cooling of bunched relativistic (β = 0.47) carbon ions at the Experimental Storage Ring (ESR) of GSI Helmholtzzentrum Darmstadt, Germany. Strongly Doppler boosted XUV fluorescence (∼90 nm) was emitted from the ions in a forward light cone after laser excitation of the 2s–2p transition (∼155 nm) by a new tunable pulsed UV laser system (257 nm). It was shown that the detected fluorescence strongly depends on the position of the detector around the bunched ion beam and on the delay (∼ns) between the ion bunches and the laser pulses. In addition, the fluorescence information could be directly combined with the revolution frequencies of the ions (and their longitudinal momentum spread), which were recorded using the Schottky resonator at the ESR. These fluorescence detection features are required for future laser cooling experiments at highly relativistic energies (up to γ∼ 13) and high intensities (up to 1011 particles) of ion beams in the new heavy ion synchrotron SIS100 at FAIR.

Portable nanopore-sequencing technology: Trends in development and applications.

Sequencing technology is the most commonly used technology in molecular biology research and an essential pillar for the development and applications of molecular biology. Since 1977, when the first generation of sequencing technology opened the door to interpreting the genetic code, sequencing technology has been developing for three generations. It has applications in all aspects of life and scientific research, such as disease diagnosis, drug target discovery, pathological research, species protection, and SARS-CoV-2 detection. However, the first- and second-generation sequencing technology relied on fluorescence detection systems and DNA polymerization enzyme systems, which increased the cost of sequencing technology and limited its scope of applications. The third-generation sequencing technology performs PCR-free and single-molecule sequencing, but it still depends on the fluorescence detection device. To break through these limitations, researchers have made arduous efforts to develop a new advanced portable sequencing technology represented by nanopore sequencing. Nanopore technology has the advantages of small size and convenient portability, independent of biochemical reagents, and direct reading using physical methods. This paper reviews the research and development process of nanopore sequencing technology (NST) from the laboratory to commercially viable tools; discusses the main types of nanopore sequencing technologies and their various applications in solving a wide range of real-world problems. In addition, the paper collates the analysis tools necessary for performing different processing tasks in nanopore sequencing. Finally, we highlight the challenges of NST and its future research and application directions.

Compact Fluorescence Detection System Based on a Monolithic DBR-Integrated III-Nitride LED Chip.

Portable applications of fluorescence detection systems have gained much attention in various fields and require system components to be small and compact. In this work, we report on a compact fluorescence detection system and demonstrate its application for fluorescence sensing and imaging. The light source and filter are integrated on a single chip for the proposed system, which not only realizes the separation between excitation and fluorescent lights but also improves the light-emitting diode (LED) light extraction efficiency. Furthermore, the detection system allows for a removable sample unit. The results indicate that the performance of the distributed Bragg reflector (DBR) filter based on an amorphous dielectric film is excellent with selection ratios larger than 4600:1. The peak emission wavelength of the LED is 528 nm. The influence of green light leakage can be neglected, and the fluorescent red light is dominant when the fluorescence detection system is used for sensing and imaging. The low-cost and monolithic DBR-integrated III-nitride LED chip makes the proposed architecture a competitive candidate for portable fluorescence detection applications.

Chromatin-Accessible miRNA Regulons Driving Thyroid Tumorigenesis and Progression.

Although papillary thyroid cancer can remain indolent, associated lymph node metastases and recurrence rates are approximately 50% and 20%, respectively. Omics-based medicine has led to the discovery of predictive biomarkers that can be used to predict tumor progression and clinical outcomes. We aimed to develop a noninvasive omics-driven blood test to allow accurate risk stratification and help tailor individual patient treatment plans. RNA sequencing (seq) and microRNA analysis of The Cancer Genome Atlas and Gene Expression Omnibus datasets were employed to identify an epigenetic prognostic panel. Integrated bulk assay for transposase-accessible chromatin-seq and RNA-seq experiments confirmed the results. Sixty-two paired tumor and adjacent control thyroid tissues and 67 blood samples (62 papillary thyroid cancer and 5 controls) were analyzed for validation using sequencing and real-time polymerase chain reaction and correlated to clinical outcomes. A liposome-exosome fusion clustered regularly interspaced short palindromic repeats (CRISPR)-fluorescent detection system miRNA assay was developed. A predictive risk nomogram was generated and tested for performance. Our miRNA panel (miR-146b-5p and miR-221-3p) from tissue and blood was associated with aggressive features and was located within accessible chromatin regions. The miRNA risk score and prognostic nomogram showed higher accuracy in predicting lymph node metastases (miR-146b: area under the curve [AUC] 0.816, sensitivity 76.9%; miR-221: AUC 0.740, sensitivity 79.5%) and recurrence (miR-146b: AUC 0.921, sensitivity 75.0%; miR-221: AUC 0.756, sensitivity 70.0%; p < 0.001) than staging and American Thyroid Association risk stratification. CRISPR-based miRNA assays showed upregulation in the blood of cancer cohorts. CRISPR-based detection of miR-146b and miR-221 in the blood of thyroid cancer patients is a reliable and noninvasive tool for real-time assessment and prognostication that has great potential to provide a direct impact on the care of these patients.

A new application of papain: As a peroxidase-like catalyst for fluorometric detection of uric acid

Papain, as a classical cysteine protease, has been widely used in the food, pharmaceutical, chemical, and cosmetic fields. However, there are few information about the peroxidase-like activity of papain catalyzed substrate to produce fluorescence. In this study, we found that papain can catalyze H2O2 to convert o-phenylenediamine (OPD), and generate fluorescence emission at 550 nm under 430 nm excitation. Based on this foundation, we report a papain/OPD/H2O2 system for fluorescence detection of uric acid. The method exhibits a wide linear range of 10–1000 μM with a limit-of-detection of 4.6 μM, and has been successfully used to detect uric acid in human serum. This study paves the way for the application of papain as catalyst for fluorescence detection of different target biomolecules, such as cholesterol, glucose, lactate, for which H2O2 is a product of oxidoreductase enzymes.

Fluorescence detection of three types of pollutants based on fluorescence resonance energy transfer and its comparison with colorimetric detection.

This study aimed at three representative pollutants, benzidine, cyromazine, and streptomycin, which were commonly used and posed a great threat to both environment and human health, mainly to explore a fast, simple, sensitive, visible naked-eye detection method. Colorimetric detection by gold nanoparticles (AuNPs) was first attempted. The cross-linking reaction occurred owing to the strong forces between the targets and AuNPs, leading to aggregation and color change. However, large-scale aggregation was easily formed and settled, which failed to achieve accurate quantification. Thus, AuNPs are considered to be used in fluorescence detection as reaction bridges. The introduction of AuNPs could effectively quench the fluorescence of Rhodamine B based on fluorescence resonance energy transfer (FRET). Moreover, a classical "on-off-on" fluorescence detection system was constructed based on nanomaterials. When AuNPs were added, the red fluorescence of the Rhodamine B solution could be effectively quenched (the "off" reaction). However, the tight cross-linking reaction between the three targets and AuNPs occurred through the strong affinity, causing Rhodamine B to dissociate in the solution. The fluorescence was rapidly restored, accompanied by a significant enhancement of fluorescence intensity (the "on" reaction). The fluorescent responses toward the three targets were established, resulting in good linearity in a wide range with low detection limits. Moreover, through the investigation of specificity, the fluorescence sensor exhibited satisfying selectivity and high binding affinity to the detected targets among the same types of inferences, indicating great potential for practical application. This simple, fast and sensitive fluorescence detection system was first used for simultaneously detecting three types of pollutants and finally successfully applied to real samples.

Fluorescence detection of apolipoprotein E gene polymorphisms based on oligonucleotide ligation and magnetic separation.

Alzheimer's disease is a progressive neurodegenerative condition that causes brain cell death and is the leading cause of dementia. Most patients with Alzheimer's disease are diagnosed with late-onset Alzheimer's disease (LOAD), with apolipoprotein E (APOE) genotypes being highly associated with the frequency of LOAD risk. A fluorescence detection system coupled with oligonucleotide ligation and magnetic separation was developed to identify two single-nucleotide polymorphisms (SNPs) for the APOE gene and recognize APOE alleles for LOAD. The system utilized a fluorescence probe with one base-discriminating nucleoside for SNP (F probe) and a perfectly complementary biotin-modified sequence against the target DNA (P probe). When the F and P probes matched the target DNA sequences, DNA ligation occurred, and ligation products were produced. Streptavidin magnetic beads were subsequently employed to remove the ligation products, and a decrease in fluorescence intensity was observed in the supernatant compared to when there was no target DNA. This system detected two SNPs of APOE alleles, namely rs429358 and rs7412. The results indicated that the R-values ((F0 - F1)/F0) for rs429358 were 0.92 ± 0.002 for the T/T target, 0.47 ± 0.004 for the T/C target and 0.11 ± 0.004 for the C/C target, respectively. The R-values for rs7412 were 0.73 ± 0.009 for the C/C target, 0.42 ± 0.001 for the C/T target and 0.16 ± 0.007 for the T/T target, respectively. F0 and F1 represent the fluorescence intensity of the F probe without and with target DNA, respectively. Based on fluorescence intensity, the fluorescence detection system was able to identify the genotypes of the APOE gene accurately to evaluate the risk of Alzheimer's disease.

Dual fluorescent hollow silica nanofibers for in situ pH monitoring using an optical fiber.

This study reports a sensitive and robust pH sensor based on dual fluorescent doped hollow silica nanofibers (hSNFs) for in situ and real-time pH monitoring. Fluorescein isothiocyanate (FITC) and tris(2,2'-bipyridyl)dichlororuthenium(ii) hexahydrate (Ru(BPY)3) were chosen as a pH sensitive dye and reference dye, respectively. hSNFs were synthesized using a two-step method in a reverse micelle system and were shown to have an average length of 6.20 μm and average diameter of 410 nm. The peak intensity ratio of FITC/Ru(BPY)3 was used to calibrate to solution pH changes. An optical-fiber-based fluorescence detection system was developed that enabled feasible and highly efficient near-field fluorescence detection. The developed system enables fully automated fluorescence detection, where components including the light source, detector, and data acquisition unit are all controlled by a computer. The results show that the developed pH sensor works in a linear range of pH 4.0-9.0 with a fast response time of less than 10 s and minimal sample volume of 50 μL, and can be stored under dark conditions for one month without failure. In addition, the as-prepared hSNF-based pH sensors also have excellent long-term durability. Experimental results from ratiometric sensing confirm the high feasibility, accuracy, stability and simplicity of the dual fluorescent hSNF sensors for the detection of pH in real samples.

A rapid and high-throughput system for the detection of transgenic products based on LAMP-CRISPR-Cas12a

With the increasing acreage of genetically modified crops worldwide, rapid and efficient detection technologies have become very important for the regulation and screening of GM organisms. We constructed a method based on loop-mediated isothermal amplification (LAMP), CRISPR-Cas12a and lateral flow assay (LAMP-CRISPR-Cas12a-LFA). It is an intuitive, sensitive and specific fluorescence detection and test strip system to detect CP4-EPSPS and Cry1Ab/Ac genes in field screening. The LAMP-CRISPR-Cas12a-LFA method has a limit of detection (LOD) of 100 copies based on lateral flow test strips after optimization of the conditions with screened specific primers, and the entire detection process can be completed within 1 h at 61 °C. The system was used to evaluate field test samples and showed high reproducibility after testing products containing CP4-EPSPS and Cry1Ab/Ac genes, and both were detectable. The LAMP-CRISPR-Cas12a-LFA method established in this paper functions as a rapid field detection method. It requires only one portable thermostatic instrument, which renders it compatible with the rapid detection of field samples and useable at experimental workstations, in law enforcement field work, and in local inspection and quarantine departments.

Research on transformer fault diagnosis based on an IWHO optimized MS1DCNN algorithm and LIF spectrum.

Accurate diagnosis of transformer faults can effectively improve the enduring reliability of power grid operation. Aiming at overcoming the problems of long time consumption and low diagnostic rate in the past diagnosis methods, this article designs a laser-induced fluorescence (LIF) detection system, which can be combined with a multi-scale one-dimensional convolution neural network (MS1DCNN) to diagnose transformer fault categories. The structural parameters of MS1DCNN are optimized using the improved wild horse optimizer (IWHO). Electrical fault oil, thermal fault oil, normal oil and locally damped oil are used as raw materials for the experiment. First, the LIF spectral data of the four kinds of oil samples are obtained, and the spectral data obtained are pretreated by standard normal variate (SNV) and multiple scattering correction (MSC), and the dimensions are reduced by linear discriminant analysis (LDA) and kernel principal component analysis (KPCA). Then the dimensionality reduced data are imported into the MS1DCNN algorithm for learning, and the parameters of MS1DCNN are optimized using the IWHO algorithm. Finally, the experiment shows that the efficiency and precision of LIF technology for raw data extraction are higher than for traditional methods; in comparison with the same type of algorithm, MSC has a better preprocessing effect, KPCA has a better dimensionality reduction effect, MS1DCNN has a better prediction effect, and IWHO has a better optimization effect. Compared to them, the MSC-KPCA-IWHO-MS1DCNN model has the best diagnostic ability, with a mean square error (MSE) of 4.9037 × 10-4, mean absolute error (MAE) of 0.0179, and goodness of fit (R2) of 0.9996. Transformer fault intelligent diagnosis is necessary for the sustained and stable operation of power networks.

Sophisticated and precise: design and implementation of a real-time optical detection system for ultra-fast PCR.

Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) has become indispensable in the realm of disease nucleic acid screening and diagnostics, owing to its remarkable precision and sensitivity, in which the real-time fluorescence detection system plays an extremely critical role. To solve the problems of long time and slow speed of traditional nucleic acid detection, PCR systems are evolving towards ultra-rapid configurations. Nonetheless, most extant ultra-rapid PCR systems either depend on endpoint detection for qualitative assessments due to inherent structural or heating constraints or circumvent the challenge of adapting optical systems to expeditious amplification systems, resulting in potential shortcomings in assay efficacy, volume, or expense. Consequently, this study proposed a design of a real-time fluorescence detection system for ultra-fast PCR, capable of executing six channels of real-time fluorescence detection. Through the meticulous calculation of the optical pathway within the optical detection module, effective regulation of system dimensions and the cost was accomplished. By devising an optical adaptation module, the signal-to-noise ratio was enhanced by approximately 307% without compromising the PCR temperature alteration rate. Ultimately, by employing a fluorescence model that accounted for the spatial attenuation effect of excitation light, as proposed herein, fluorescent dyes were arranged to evaluate the repeatability, channel interference, gradient linearity, and limit of detection of the system, which proved that the system had good optical detection performance. Finally, the real-time fluorescence detection of human cytomegalovirus (CMV) under 9 min ultra-fast amplification was achieved by a complete ultra-fast amplification experiment, which further validated the potential of the system to be applied to rapid clinical nucleic acid detection.

Open Laboratory Teaching Design of Instrumental Analysis:Construction of a Modular Laser-Induced Fluorescence Detection System Based on LEGO Blocks

Open Laboratory Teaching Design of Instrumental Analysis:Construction of a Modular Laser-Induced Fluorescence Detection System Based on LEGO Blocks

Multiple real-time fluorescence detection system for rapid on-site nucleic acid detection

Multiple real-time fluorescence detection system for rapid on-site nucleic acid detection

Delineation of the healthy rabbit heart by immunohistochemistry – A technical note

Heart failure poses a big health problem and may result from obesity, smoking, alcohol and/or growing age. Studying pathological heart tissue demands accurate histological and immunohistochemical stainings in animal models, including chromogenic and fluorescent approaches. Moreover, a reliable set of healthy heart stainings and labeling are required, in order to provide a reference for the pathological situation. Heart and brain tissue of a healthy rabbit were collected, and different histological key steps were compared, such as paraffin embedding after formalin fixation versus cryopreservation; an antigen retrieval (AR) step in processing paraffin sections versus the same procedure without AR; or a chromogenic with a fluorescent detection system, respectively. Using serial sections, we stained the same morphological structure with classic approaches (HE, Masson Goldner Trichrome (GT) and Elastica van Gieson (EL)) and with different markers, including collagen I, collagen III, fibronectin, α-SMA, protease-activated receptor-2 (PAR-2) which is an inflammation-related marker, and ki67 for proliferating cells. Differences between conditions were quantitatively assessed by measuring the color intensity. Generally, cryosections exhibited a more prominent signal intensity in immunohistochemically labeled sections than in paraffin sections, but the strong staining was slurry, which sometimes impeded proper identification of morphological structures, particularly at higher magnifications. In addition, the advantage of an AR step was observed when compared to the condition without AR, where signal intensities were significantly lower. Different stainings of the heart arteries and the myocardium revealed a clear distribution of extracellular matrix components, with prominent collagen III in the artery wall, but an absence of collagen III in the myocardium. Moreover, paraffin-embedded sections provided more distinct structures compared to cryosections after collagen III, ki67, fibronectin, and α-SMA labeling. As for the Purkinje cells that were depicted in the heart and the cerebellum (Purkinje neurons), we found GT staining most suitable to depict them in the heart, while HE as well as EL staining was ideal to depict Purkinje neurons in the cerebellum. In sum, we provide useful reference images with different stainings for researchers using the rabbit heart or brain model. Such images can help to decide which of the immunohistochemical protocols are valuable to reach a specific aim. Recommendations are given for the best visualization of the target structures and specific (immunohistochemical) staining.

A nitrogen-doped fluorescent carbon dot for gallium occurrence investigation in environment

Gallium element had a good application prospect in semiconductor industry. The increase of gallium consumption led to elevated levels of gallium in the environment, so it was important to accurately explore gallium morphology in the environment and establish effective analytical methods. In this study, ammonium citrate was used as carbon and nitrogen sources to obtain water-soluble nitrogen-doped fluorescent carbon dots (N-CDs) under the hydrothermal synthesis condition of 160 °C. Fluorescence test showed that N-CDs has bright blue luminescence, pH-sensitivity and good stability under certain temperature, continuous ultraviolet irradiation and high salt concentration. There was a good linear relationship between Ga3+ concentration and fluorescence ratio (F0/F) when Ga3+ concentration was 1–10 μM, and the correlation coefficient was 0.999. Ion selectivity experiments showed that N-CDs had good selectivity and sensitivity to Ga3+ as fluorescent probes. Based on these characteristics, the fluorescence detection system of Ga3+ was established. Studies had shown that this method could be applied to the determination of Ga3+ in water samples and coal ash samples.

Studying the Fluorescence Resonance Energy Transfer Between Two Dyes of Laser in an Aqueous Solution

In the past quarter century, applications of fluorescence resonance energy transfer (FRET) have grown dramatically, and the technology has become an indispensable tool in a wide variety of biological and biophysical domains. It is utilized, in order to acquire information on the conformational changes that occur in single molecules. By utilizing the fluorescence correlation spectroscopy, the pharmaceutical sector has also built huge fluorescence detection systems with extremely small sample sizes, reaching down to the level of single molecules. The fluorescence resonance energy transfer (FRET) between the two dyes, Acriflavine (Acf) and Rhodamine B (RhB), were examined in solution. Energy transfer was observed in fluorescence resonance imaging solutions containing Acriflavine and Rhodamine B with different concentrations of the acceptor RhB dye in the range of (1.5×10-5 M to 3.5×10-5M). Studies using Both UV–Vis absorption and fluorescence spectroscopy demonstrated that the two dyes, when dissolved in solution, appear largely as monomers.

Educational Review: Intraoperative Parathyroid Fluorescence Detection Technology in Thyroid and Parathyroid Surgery.

Accurate parathyroid gland (PG) identification is a critical yet challenging component of cervical endocrine procedures. PGs possess strong near-infrared autofluorescence (NIRAF) compared with other tissues in the neck. This property has been harnessed by image- and probe-based near-infrared fluorescence detection systems, which have gained increasing popularity in clinical use for their ability to accurately aid in PG identification in a rapid, noninvasive, and cost-effective manner. All NIRAF technologies, however, cannot differentiate viable from devascularized PGs without the use of contrast enhancement. Here, we aim to provide an overview of the rapid evolution of these technologies and update the surgery community on the most recent advancements in the field. A PubMed literature review was performed using the key terms "parathyroid," "near-infrared," and "fluorescence." Recommendations regarding the use of these technologies in clinical practice were developed on the basis of the reviewed literature and in conjunction with expert surgeons' opinions. The use of near-infrared fluorescence detection can be broadly categorized as (1) using parathyroid NIRAF to identify both healthy and diseased PGs, and (2) using contrast-enhanced (i.e., indocyanine green) near-infrared fluorescence to evaluate PG perfusion and viability. Each of these approaches possess unique advantages and disadvantages, and clinical trials are ongoing to better define their utility. Near-infrared fluorescence detection offers the opportunity to improve our collective ability to identify and preserve PGs intraoperatively. While additional work is needed to propel this technology further, we hope this review will be valuable to the practicing surgeon.

Glucose and pH responsive fluorescence detection system based on simple synthesis of silicon-coated perovskite quantum dots

Perovskite quantum dots (PQDs) are extremely unstable in ambient air due to their inherent structural instability, which limits the wide application of PQDs. In this work, silicon-coated CsPbBr3 PQDs (CsPbBr3@SiO2) was synthesized via a simple method. The SiO2 coating effectively isolated PQDs from water and oxygen in the environment, which were the main elements that destroyed the structure stability of PQDs. The synthesized CsPbBr3@SiO2 can be stored in water for more than 2 months and posessed wonderful dispersibility in aqueous solution. The fluorescence intensity remained unchanged within 7 days and only decreased by 11.9 % within 2 months. We found that CsPbBr3@SiO2 was extremely sensitive to environmental pH, and the fluorescence intensity decreased with the reduction of pH. In addition, an excellent linear relationship with pH value in the range of 1.0 ∼ 5.0 was achieved. As we all known that glucose can be catalyzed by glucose oxidase to produce gluconic acid and hydrogen peroxide, in which a good deal of protons were produced and the pH was gradually lowered. Since CsPbBr3@SiO2 was stable to water and oxygen, and sensitive to ambient pH, we applied CsPbBr3@SiO2 to the detection of glucose. CsPbBr3@SiO2 showed fantastic selectivity and sensitivity to glucose, and the detection limit can even reach 18.5 μM. Furthermore, CsPbBr3@SiO2 was successfully applied to the detection of glucose in the human serum with satisfactory performance.