277 results about "Signalling molecules" patented technology

The invention discloses an all-optical three-dimensional scanning confocal fluorescent microscopic imaging device and an implementation method thereof. According to the invention, through a deep learning driven adaptive regulation and control method, CNN is adopted to process spatial distribution data and dynamically regulate and control a phase hologram and the light intensity and phase compensation of a laser, so that the focal point of exciting light is subjected to aberration-free axial displacement, a bidirectional parallel optical scanning track of a two-dimensional scanning system is optimized, and all-optical three-dimensional scanning is realized; lSTM and TCN are combined to obtain a time sequence dependency relationship, a laser light source, an adjustable diaphragm, an electric focus-adjustable lens and a photoelectric detector are integrally controlled, efficient synchronization and automatic operation and high-speed axial focusing adjustment are realized, errors and time sequence mismatch are eliminated, optical characteristics of different samples and environmental interference are automatically adapted, and high-quality imaging is kept. The robustness and the applicable scene range of the system are improved; the method is used for model biological embryo real-time tracking, intracellular signal molecule dynamic visualization, cell membrane protein migration and aggregation observation and intracellular organelle interaction tracking.

The invention belongs to the field of microbial preparations, and particularly relates to a complex microbial inoculant for promoting microbial quorum sensing and application of the complex microbial inoculant in compost. The composite microbial agent comprises pseudomonas A3 and paenibacillus polymyxa 21-2, and the preservation number of the pseudomonas A3 is CCTCC (China Center for Type Culture Collection) NO: M20251394. The pseudomonas A3 can express key genes such as rhlI and lasI of a gram-negative bacteria AHL quorum sensing system and signal molecules of the key genes, and the paenibacillus polymyxa 21-2 can express luxS genes of a gram-positive bacteria AI-2 signal system and signal molecules DPD of the luxS genes. In the pig manure compost, the complex microbial inoculant is added, so that the expression of AI-2 and AHLs system related genes in the compost and the content of signal molecules DPD are remarkably improved, the microbial population sensing process of the compost is promoted, finally, the compost temperature is increased by about 6 DEG C, the compost carbon-nitrogen ratio is reduced, and the compost maturity is promoted.

The invention belongs to the field of membrane pollution control, and particularly relates to pseudomonas as well as a separation method and application thereof. The invention provides a pseudomonas, which is identified as Pseudomonas knackmussii HITSZ-Q1, is preserved in the Guangdong Microbiological Culture Collection Center, and has the preservation number of GDMCC (China General Microbiological Culture Collection Center) NO: 66162. The strain takes C6-HSL as the unique carbon source and nitrogen source, and the 16S rDNA sequence of the strain is as shown in SEQ ID NO. 1. The strain has a remarkable degradation capability on signal molecules such as C6-HSL, C8-HSL, 3-oxo-C12-HSL and the like, and the highest quenching rate can reach 98.9%. The strain and pseudomonas aeruginosa are co-cultured, so that the signal molecule concentration of the pseudomonas aeruginosa can be effectively reduced, and biofilm formation is inhibited. The strain is further prepared into a carrier in the form of immobilized pellets, the carrier is added into a membrane bioreactor, the operation cycle is prolonged from 6.5 days to 10.5 days, and the membrane pollution delay rate reaches up to 61.5%.

A viral particle. The surface of the viral particle comprises a T cell activation primary signaling molecule and a T cell activation secondary signaling molecule; the envelope glycoprotein of the viral particle is subjected to a first mutation, so that the receptor binding ability of the viral glycoprotein is weakened or lost with respect to its receptor binding ability before the first mutation; and the envelope glycoprotein of the viral particle can also be subjected to a second mutation, so that the viral particle has enhanced resistance to complement-mediated inactivation or is not subjected to complement-mediated inactivation. The viral particle has improved specificity for targeted activation, stimulation and transduction of non-activated T cells, and is thus more applicable for the preparation of CAR-T cells in subjects.

The embodiment of the invention provides an organ chip, and relates to the technical field of organ chips, the organ chip comprises at least two function parts and a dielectric layer located between the two adjacent function parts, the at least two function parts are stacked, and each function part is provided with a cell culture chamber; the dielectric layer is used for isolating contact between cells of adjacent cell culture chambers and allowing interaction and substance exchange between signal molecules between the adjacent cell culture chambers, and through the stacked functional part and dielectric layer structure, interaction of the signal molecules is allowed while different cell culture chambers are physically isolated; the air guide part and the connector of the culture box are tightly pressed, the air pressure regulation and control precision and the culture environment stability are guaranteed, the air pressure stability in the culture box is effectively guaranteed, and external microorganisms, dust and other pollutants are effectively prevented from invading the culture environment.

The invention discloses a phycomycete symbiotic system and application of the phycomycete symbiotic system in treatment of aquaculture tail water, and belongs to the technical field of tail water treatment. The phycomycete symbiotic system comprises chlorella, scenedesmus and activated sludge, and the initial inoculation dry weight ratio of the chlorella to the scenedesmus to the activated sludge is 1: 1: 6. And exogenously adding octanoyl-L-homoserine lactone or tetradecanoyl-L-homoserine lactone into the phycomycetes symbiotic system, so as to construct the phycomycetes symbiotic system with enhanced functions. On the basis of a mixed algae-bacteria symbiotic system with an optimized ratio, directional enhancement of functions is realized by virtue of quorum sensing signal molecules, the stability and resistance gene interception capability of the quorum sensing signal molecules under the stress of antibiotics are verified, and finally efficient purification of the aquaculture tail water is realized. According to the invention, the blank of the prior art in the aspects of advanced regulation and control of a phycomycete synergistic mechanism and synergistic treatment of emerging pollutants is filled up.

The invention discloses an electrochemical biosensing system for detecting BVDV (bovine viral diarrhea virus) based on CRISPR-Cas13a (clustered regularly interspaced short palindromic repeats). The electrochemical biosensing system comprises an electrochemical biosensor and a CRISPR-Cas13a system, the electrochemical biosensor comprises a working electrode, and the surface of the working electrode is modified with an MB-RNA probe; one end of the MB-RNA probe is modified with sulfydryl, the other end of the MB-RNA probe is modified with signal molecules, and the MB-RNA probe is connected with the working electrode through an Au-S bond; the CRISPR-Cas13a system comprises a crRNA (Complementary Ribonucleic Acid) group and Cas13a; and the crRNA group comprises at least one of BVDV (bovine viral diarrhea virus)-crRNA 2, BVDV-crRNA 7, BVDV-crRNA 8, BVDV-crRNA 11, BVDV-crRNA 12 and BVDV-crRNA 14. The electrochemical biosensing system disclosed by the invention has extremely high clinical sensitivity and clinical specificity on the BVDV virus.

The invention discloses an engineered macrophage and a pharmaceutical composition and application thereof, and CCM3 expression in the engineered macrophage is inhibited, so that the engineered macrophage is polarized towards the M2 direction or the engineered macrophage is an M2 type macrophage. Besides, the invention further develops a temperature-sensitive cell-loaded hydrogel preparation which can promote polarization of macrophages in the M2 direction by inhibiting expression of signal molecules CCM3 on adhesion spots, and the temperature-sensitive cell-loaded hydrogel preparation can promote bone defect immune osteogenesis through local injection.

The invention relates to the technical field of fertilizers, and discloses an amino acid-containing water-soluble fertilizer and a preparation method thereof, and the method comprises the steps of raw material preparation, carrier system construction, signal molecule extraction and activation, stress-resistant amino acid compound preparation, multi-element synergistic system construction and the like. Through innovative combination of a soil penetrating carrier system and a plant source signal molecule technology, the technical problems of weak penetrating power, low bioavailability and the like of active components of a fertilizer in saline-alkali soil are solved, so that the effective penetrating depth of signal molecules in severe saline-alkali soil is effectively improved, the bioavailability is improved, and the application prospect is wide. The saline-alkali resistance of the plants is obviously enhanced, and the ecological restoration and sustainable utilization of the saline-alkali soil are promoted.

The invention relates to a Raman probe for detecting hydrogen sulfide as well as a preparation method and application of the Raman probe. The gold and silver nanocage (AuAg NCs) is prepared, and after the gold and silver nanocage (AuAg NCs) is modified by a Raman signal molecule 4-ethynylaniline (4EA), it is found that the AuAg-4EANCs shows the strongest Raman enhancement effect at the position of 2010 cm <-1 > located in a cell silence zone. The SERS probe with the tumor targeting capability is developed through the functional modification of a mucoprotein 1 aptamer (MUin1aptamer, MUC1Apt) and polyethylene glycol (PEG), and the SERS probe with the tumor targeting capability is further developed through the functional modification of the mucoprotein 1 aptamer (MUin1aptamer, MUC1Apt) and the PEG (Polyethylene Glycol). In the presence of hydrogen sulfide (H2S) and oxygen, Ag in AuAg-4EANCs rapidly reacts with H2S to generate Ag2S with significantly reduced Raman enhancement performance, resulting in sharp attenuation of 4EA signal intensity. And along with the increase of the H2S concentration, the generation amount of Ag2S is increased, so that a quantitative detection model dependent on the H2S concentration is established.

The invention discloses a preparation method of cells with LTo-like functions, which is characterized in that adipose tissue-derived stem cells are treated by LTo differentiation induction signal molecules to obtain cells with LTo-like phenotypes, secretion of cytokines and chemotactic factors of the cells is up-regulated, and the cells have recruitment and support capabilities on lymphocytes in vivo and in vitro. The problems that LTo cells are rare and difficult to obtain are solved, and the adipose-derived stem cells are higher in efficacy, easy to obtain and culture in vitro, capable of being massively amplified, low in cost, efficient and safe.

The invention relates to the technical field of sewage treatment, in particular to application of a signal molecule C8-HSL in strengthening sewage treatment of algal-bacterial symbiotic granular sludge. In-depth study finds that the signal molecule C8-HSL can improve the TN removal rate of the system; according to the present invention, with the application of the signal molecules, the flora composition is changed, the enrichment of denitrification functional bacteria such as Hydrogenphaga, Pseudoxanthobacteria and the like is promoted, and the abundance of the complex organic matter degrading bacteria Desulfomicrobe is enhanced; meanwhile, due to the increase of denitrifying bacteria such as Hydrogenphaga, Thauera and Zoogloea, the variety of species is optimized, and the nitrogen removal efficiency and the organic matter degradation efficiency are improved; based on PICRUSt2 analysis, the signal molecule C8-HSL can increase the abundance of the napAB gene and promote aerobic denitrification; expression of nirK and nirS genes is enhanced, and nitrite is promoted to be converted into nitrogen; meanwhile, the signal molecule C8-HSL effectively improves the denitrification performance of the system by optimizing a nitrogen metabolism pathway.

The invention discloses a fluorescent array sensing system based on bionic taste sense, a construction method of the fluorescent array sensing system and application of the fluorescent array sensing system in food safety intelligent detection. According to the system, a functionalized ultrathin Ti3C2 MXene nanosheet serves as a bionic tongue carrier, multicolor silver nanoclusters synthesized by oligonucleotide chains are adsorbed on the surface of the functionalized ultrathin Ti3C2 MXene nanosheet to serve as bionic taste bud cells, different DNA chains can form different fluorescence emissions, the characteristic that fluorescence can be designed is achieved, and the preparation process of signal molecules can be greatly simplified. When a plurality of hazardous substances are added into the sensing array at the same time, the Ti3C2 MXene with strong binding capacity can preferentially capture a target object, and the silver nanoclusters with weak binding capacity can release or adsorb, so that fluorescence signals with different colors are changed, and a characteristic fingerprint spectrum is formed. And in combination with a machine learning algorithm, rapid, accurate, qualitative and quantitative intelligent identification of multiple food hazardous substances can be realized at the same time, and a new strategy is provided for simultaneous detection of multiple hazardous substances in food safety.

The invention discloses a stem cell preparation for scalp hair follicle regeneration and a preparation method thereof, and relates to the technical field of biological agents, and the stem cell preparation comprises the following raw materials: exosome, normal saline, alpinetin extract and hydrogel. According to the stem cell preparation for scalp hair follicle regeneration and the preparation method of the stem cell preparation, mRNA, miRNA and protein carried by the exosome can act on hair follicle stem cells in a targeted mode, cell cycle related genes are activated, and cells are promoted to enter a proliferation period from a G0 period; meanwhile, by transmitting BMP, Notch and other signal molecules, hair follicle stem cells are inhibited from being differentiated into epidermal cells, the hair follicle stem cells are induced to be differentiated into hair follicle specific cells, and reconstruction of a hair follicle structure is promoted; anti-inflammatory factors in the exosome can inhibit excessive activation of fibroblasts around hair follicles, reduce collagenous fiber deposition and relieve inhibition of fibrosis on hair follicle regeneration; meanwhile, the levels of TNF-alpha, IL-6 and other proinflammatory factors are reduced, and a suitable growth environment is provided for hair follicle stem cells.

The invention relates to the technical field of soil fertility management, in particular to a production quality control method of a special fertilizer for Yunnan cigar tobacco leaves, which comprises the following steps: step 1, preparing a waste-based functional carrier; step 2, signal response type fermentation control: based on a dynamic monitoring result of microbial population sensing signal molecules in a fermentation system, regulating and controlling the injection opportunity of an exogenous inducer and fermentation environment parameters, and directionally synthesizing a targeted antibacterial metabolite; step 3, adaptive packaging in a growing period; and 4, bionic verification and closed-loop optimization: verifying a nutrient release curve through a bionic root system simulation device, and feeding back and adjusting packaging parameters in combination with a field metabolite detection result to form a production-application self-optimization system. The production efficiency and fertilizer efficiency of the cigar tobacco leaf fertilizer are improved through accurate process control, it is ensured that nutrient supply and release of the fertilizer in all growth periods have excellent matching performance, and the effect of the fertilizer can be optimized in practical application.

The invention provides a Raman enhanced nano-label based on a polydopamine core-shell structure, a preparation method and application of the Raman enhanced nano-label in immunochromatography, and relates to the technical field of immunochromatography. The Raman enhanced nano-label based on the polydopamine core-shell structure sequentially comprises a PDA microsphere core, a PEI layer and a gold and silver nano-particle layer from inside to outside, the gold and silver nanoparticle layer is gold and silver nanoparticles with a core-shell structure; the gold and silver nanoparticle layer is connected with a Raman signal molecule DTNB, and a terminal carboxyl group of the Raman signal molecule DTNB is coupled with a capture antibody of an H1N1 virus or a capture antibody of an SARS-CoV-2 virus. The nano-label has colorimetric and SERS enhanced activity at the same time, has the advantages of rich hot spots, high stability, excellent optical performance and the like, is used for an immunochromatography sensor to detect two respiratory viruses at the same time, adopts qualitative and quantitative dual-mode detection, and improves the detection flexibility, sensitivity and accuracy.

The present invention relates to the field of polypeptide induction technology, and discloses a polypeptide-induced bio-fermentation culture medium optimization method and system, including building an ideal experimental environment condition suitable for the bio-fermentation culture medium, adding a preset concentration of polypeptide as a signal molecule between the time when the cells enter the product induction period from the logarithmic growth phase; detecting the actual yield of the target product in the culture medium after the product induction period, the actual yield refers to the ratio increased by adding the polypeptide as a signal molecule on the original basis, and when the actual yield is less than the standard yield, executing the polypeptide concentration optimization strategy. The present invention utilizes a method of adding polypeptide signals in stages and steps within a window period, and detects the target product concentration in real time and calculates the real-time yield rate, thereby accurately identifying the window period to be optimized where the reaction effect is not obvious, so as to optimize the polypeptide addition conditions for the window period to be optimized.

This invention discloses an amplification-free electrochemical biosensor and method based on CRISPR-Cas13a. The sensor includes an electrochemical biosensor substrate, a dual-channel RNA reporter molecule, a CRISPR-Cas13a reaction system, and a dual-channel differential signal processing module. The working electrode surface is immobilized with a stem-loop structured first reporter molecule and a linear second reporter molecule loaded with gold nanoparticles, labeled with methylene blue and ferrocene signal molecules respectively, and immobilized with a ferrocene-specific capture probe. When target RNA is present, Cas13a is activated and non-specifically cleaves the reporter molecule, reducing the methylene blue signal and enriching and enhancing the ferrocene signal. Background self-calibration is achieved through dual-channel differential ratio calculation. This invention integrates signal attenuation and signal enhancement modes, offering advantages such as nucleic acid amplification-free operation, fast detection speed, high sensitivity, and strong anti-interference capability.

The invention relates to an application of a nanosphere fluorescent probe combined CRISPR (clustered regularly interspaced short palindromic repeats) in detection of exosomes, which comprises the following steps: inserting DNA nanospheres as a carrier of fluorescent signal molecule methylene blue into a cholesterol probe on an exosome membrane to start a strand displacement reaction, activating trans-cleavage activity of Cas12a by a reaction product to split the DNA nanospheres wrapped with methylene blue, further, qualitative and quantitative analysis of the exosome is realized through fluorescence signal detection of methylene blue. Compared with a common CRISPR / Cas-based biosensing platform, the nanosphere fluorescent probe and the CRISPR are combined, so that high-sensitivity detection of the exosome can be realized, and the application scene of the nucleic acid nanoprobe and the CRISPR-Cas system in fluorescent biosensing is widened.

The application discloses an electrochemical sensor for detecting IBD protein markers and a preparation method thereof. The electrochemical sensor is composed of a CNT-embedded semi-cured PDMS flexible substrate, deposited gold nanoparticles and a nucleic acid sensing layer. The nucleic acid sensing layer comprises a tumor necrosis factor-alpha sensor, an interleukin 6 sensor, an interleukin 8 sensor, a transforming growth factor beta 1 sensor, a reference electrode and a counter electrode. The tumor necrosis factor-alpha sensor, the interleukin 6 sensor, the interleukin 8 sensor and the transforming growth factor beta 1 sensor all adopt single-stranded aptamers modified by a signal molecule methylene blue, and the nucleotide sequences corresponding to the single-stranded aptamers are SEQ ID NO. 1-4. The application can improve the modulus matching of the sensor and human tissue and excellent biocompatibility, realize accurate detection of low-concentration biomarkers and stable signal output of the sensor under a strain working condition.

The invention belongs to the technical field of biology, and discloses a peptide signal molecule GhEG45 and application of a gene engineering product of the peptide signal molecule GhEG45 in plant growth regulation and disease resistance. The gene coding sequence of the peptide signal molecule GhEG45 is as shown in SEQ ID NO. 1, and the amino acid sequence of the peptide signal molecule GhEG45 is as shown in SEQ ID NO. 2. The peptide signal molecule GhEG45 can prevent and treat cotton verticillium wilt and regulate plant growth, can also be used for cultivating new varieties of transgenic plants resisting V.dahliae infection, improves the disease resistance and stress resistance of the plants, plays a role in regulating plant growth, increases both production and income, and improves crop quality.

The present invention provides a compound that can hydrolyze and release HNO under physiological conditions. This compound can release HNO, an endogenous signaling molecule, providing a new donor compound for HNO research. Furthermore, the compound can simultaneously release a fluorescent molecular probe while releasing HNO, allowing fluorescence detection technology to monitor changes in fluorescence intensity during HNO release.

The invention discloses a broad-spectrum plant-source disease-resistant excitant for rice blast and a preparation method thereof, and belongs to the technical field of rice blast prevention and control, in the broad-spectrum plant-source disease-resistant excitant, potassium glutamate serves as amino acid salt, not only provides a nitrogen source for plants, but also participates in the metabolic process in the plants and enhances the stress resistance of the plants. S-allyl-L-cysteine is a sulfur-containing amino acid derivative, has antioxidant and disease-resistant activity, and can stimulate a defense mechanism of plants and resist infection of magnaporthe oryzae. 2-piperidinecarboxylic acid has the effect of inhibiting growth of pathogenic bacteria and can directly interfere with cell wall synthesis of magnaporthe oryzae, so that diseases are relieved. Chitosan as a biological polysaccharide can induce plants to generate resistant substances, enhance the strength of plant cell walls, form a physical barrier and prevent invasion of pathogenic bacteria. Salicylic acid is an important signal molecule in a plant body and can activate systematic resistance of the plant and improve the overall disease resistance.

The application discloses a preparation method of a photoelectrochemical immunosensor for detecting carcinoembryonic antigen + The signal amplification strategy of liposomes and Bi2S3@BiOI heterojunction as a base material are used to successfully construct a PEC immunosensor of Bi2S3@BiOI / Ag2S ternary heterojunction, and the PEC immunosensor is used for detecting the content of carcinoembryonic antigen. Specifically, a sandwich immunocomplex is formed through specific recognition of the aptamer fixed on the magnetic beads, the aptamer labeled on the liposomes and CEA, methanol as a demulsifier is added, the liposomes are broken to release a large number of signal molecules Ag + . The released Ag + is transferred to the surface of the electrode modified by Bi2S3@BiOI to form Ag2S with a narrow band gap in situ, the ternary heterojunction of Bi2S3@BiOI / Ag2S is formed due to the existence of the energy level matching relationship, the light absorption range is expanded, the separation of photoinduced electron-hole pairs is accelerated, the photocurrent signal is enhanced, and the purpose of signal amplification is achieved.

The invention is applicable to the technical field of biosensors, and provides a preparation method of a nanoparticle array type SERS (Surface Enhanced Raman Scattering) substrate with an Au-CeO2 (at) 4MPBA Janus structure, which comprises the following steps: step 1, synthesizing nanoparticles with the Au-CeO2 (at) 4MPBA Janus structure; step 2, assembling a nanoparticle array SERS (Surface Enhanced Raman Scattering) substrate; and step 3, constructing a diagnosis and treatment integrated platform. According to the method, through a metal-semiconductor heterojunction structure, nanoparticles with relatively simple morphology have high-strength SERS hot spots. 4-MPBA multifunctional small molecules are modified on the surfaces of the nano particles, and the small molecules have the functions of regulating the particle spacing, providing Raman signals as signal molecules and capturing molecules of bacteria at the same time. The prepared SERS detection platform shows considerable enzymatic activity and photo-thermal performance, so that the SERS biosensor can be used for removing captured bacteria.

The invention belongs to the technical field of nerve cell culture, and particularly relates to application of a culture medium in co-culture of SVGP12 and HMEC-1. The culture medium is based on a mixture of DMEM and MCDB 131 according to a ratio of 1: 1, HEPES, Glutamax, N2, G-5, B-27, hEGF, penicillin-streptomycin and fetal calf serum are added, and the components are prepared according to a specific final concentration. When being applied to a Transwell co-culture model, the culture medium can meet the nutritional requirements of two cells at the same time, maintain the normal growth and form of the cells, and promote the transmission of functional signal molecules. Experiments show that the culture medium can significantly up-regulate expression of ABCG2, CYP2D6, CYP1B1 and CYP2E1 in HMEC-1 (P is less than 0.05), provides a reliable in-vitro model for researching an interaction mechanism of two cells, and assists drug screening and disease simulation.

The sensors (4) can be used to detect the concentration of an analyte, such as an electrolyte and / or a blood gas. In some models, these sensors may include a matrix material, a nanoparticle (2) associated with the matrix material, and a signaling molecule (10, 12, 14, 16) associated with the nanoparticle. In some cases, the signaling molecule may exhibit a fluorescence emission intensity (20, 22, 24, 26) as a function of the analyte concentration. Abbreviated figure: Fig. 2.

The present application relates to the technical field of natural product extraction, and provides mulberry root bark extract and a preparation method thereof.The extract contains 3-8 characteristic components among eight characteristic components of mulberry flavone C, morusin, cyclo-morusin, cyclo-moracen, mulberroside G, morusin M, mulberroside C and mulberry flavone H.Further, the content relationship of four key components, the proportion of 300-800 Da components, the proportion of >1000 Da components, the content of fat-soluble resin impurities and the proportion of chromatographic peak area are coupled and limited by stability index S and synergy index T.The preparation method comprises the following steps: acid buffer infiltration, ethanol ultrasonic reflux extraction, concentration and adjustment of polarity, sedimentation separation, supercritical carbon dioxide impurity removal, resin column narrow window chromatographic separation, microfiltration-ultrafiltration-nanofiltration separation and drying.The obtained extract can regulate the expression of inflammation-related factors and promote the recovery of intracellular signal molecule level, thereby showing good soothing and skin barrier repair effects at the cell level.

The invention belongs to the technical field of biosensing detection, and particularly discloses a label-free ratio fluorescence sensor and application thereof in quinine detection. The label-free ratio fluorescent aptamer sensor takes isothiocyanate as an internal reference signal and a fluorescent dye as a detection signal, and is obtained by mixing and incubating a quinine specific nucleic acid aptamer, a triphenylmethane fluorescent dye and isothiocyanate in a buffer solution. According to the invention, isothiocyanate is introduced as an internal reference signal, triphenylmethane dye is selected as a target response fluorescence signal molecule, and the quinine is detected by using the obvious fluorescence change of the target response fluorescence signal molecule in the binding-dissociation process of the target response fluorescence signal molecule and a quinine specific nucleic acid aptamer. The label-free ratio fluorescence sensor has excellent selectivity and stability, can be widely applied to the fields of food safety supervision, drug quality control, environmental water quality detection and the like, and is particularly suitable for rapid detection and emergency monitoring of quinine under the condition of limited resources.

Cyclic dinucleotides (CDRs) are signaling molecules for cancer therapy, acting as second messengers for intracellular events initiated by GPCR activation and stimulating factors for the interferon gene (STING), thus significantly influencing tumor suppression. Simultaneously, when cancer occurs in a subject, angiogenesis and cell growth proceed at very high rates in vivo, creating a hypoxic environment due to incomplete angiogenesis in cancerous tissue. This environment can be highly conducive to the proliferation of anaerobic bacteria such as Salmonella strains or Escherichia coli. Therefore, this invention relates to a DNA construct incorporating a gene encoding an enzyme for synthesizing cancer therapeutic signaling molecules (e.g., CDRs), or to strains transformed with a vector containing the DNA construct. According to the invention, the DNA construct or strains transformed with a vector containing the DNA construct target cancer in a subject and then secrete C-di-AMP or C-di-GMP synthases in the surrounding environment of the cancer, thus enabling highly effective prevention or treatment of cancer while allowing for real-time cancer diagnosis.