124 results about "Fluorescence biosensor" patented technology

Improved polymer matrices which incorporate fluorescent biosensor molecules as well as methods of making and using these polymer matrices are described. Such matrices can be used in fluorescent biosensors and biosensor systems, including those which are used in the detection of polyhydroxylated analytes such as glucose. The properties of the polymer matrices of the invention renders biosensors utilizing such matrices particularly well-suited for detecting and measuring in-vivo glucose concentrations.

Fluorescent biosensor molecules, fluorescent biosensors and systems, as well as methods of making and using these biosensor molecules and systems are described. Embodiments of these biosensor molecules exhibit fluorescence emission at wavelengths greater than about 650 nm. Typical biosensor molecules include a fluorophore that includes an iminium ion, a linker moiety that includes a group that is an anilinic type of relationship to the fluorophore and a boronate substrate recognition/binding moiety, which binds glucose. The fluorescence molecules modulated by the presence or absence of polyhydroxylated analytes such as glucose. This property of these molecules of the invention, as well as their ability to emit fluorescent light at greater than about 650 nm, renders these biosensor molecules particularly well-suited for detecting and measuring in-vivo glucose concentrations.

The invention discloses a fibre-optical fluorescent biological sensor, which comprises the following parts: optical exciting path, optical detecting path and fluorescent receiving optical path, wherein three optical paths are connected on three branches of Y-shaped optical fiber; the optical exciting source utilizes the coupling light to couple on one branch of Y-shaped optical fiber on the optical exciting path; another branch of Y-shaped optical fiber is used to fix biological identifier, which is connected with the carrier or sample pond; the third branch of Y-shaped optical fiber is connected with the data gathering system, which is connected with signal disposing and display system further. The invention possesses rapid response, high sensitivity, good selectivity, light weight, small bulk and good friend biological property, which is fit for all fluorescent markers in the biological molecular identifying, medical clinical diagnosis, high-flux drug sieving, environment monitoring, and biochemical agent detecting domain.

The invention relates to a fluorescence biosensor, and a preparation method and a purpose thereof. On the basis of a two-dimensional manganese dioxide nanometer sheet as a fluorescence sensing platform, morpholineethanesulfonic acid is used for reducing potassium permanganate for synthesizing the manganese dioxide nanometer sheets; the manganese dioxide nanometer sheets adsorb FAM-ssDNA and quench FAM fluorescence; under the effect of alkaline phosphatase, vitamin C magnesium L-ascorbate-2-phosphate is hydrolyzed to generate ascorbic acid; the two-dimensional manganese dioxide nanometer sheets are reduced into manganese ions by the ascorbic acid; FAM-ssDNA is released; the fluorescence is recovered; the fluorescence sensor using the manganese dioxide nanometer sheets and the alkaline phosphatase to regulate the fluorescence intensity is built and is used for detecting the activity of the alkaline phosphatase. Compared with the prior art, the fluorescence biosensor has the characteristics of simplicity, high speed, low background signal, high sensitivity, low detection limit and good selectivity by using the change of the two-dimensional manganese dioxide nanometer sheets on the fluorescence signal, i.e., the off-on mode for detecting the alkaline phosphatase.

Fluorescent biosensor molecules, fluorescent biosensors and systems, as well as methods of making and using these biosensor molecules and systems are described. These biosensor molecules address the problem of obtaining fluorescence emission at wavelengths greater than about 500 nm. Biosensor molecules generally include an (1) an acridine-based fluorophore, (2) a linker moiety and (3) a boronate substrate recognition/binding moiety, which binds polyhydroxylate analytes, such as glucose. These biosensor molecules further include a “switch” element that is drawn from the electronic interactions among these submolecular components. This fluorescent switch is generally “off” in the absence of bound polyhydroxylate analyte and is generally “on” in the presence of bound polyhydroxylate analyte. Thus, the reversible binding of a polyhydroxylate analyte essentially turns the fluorescent switch “on” and “off”. This property of the biosensor molecules, as well as their ability to emit fluorescent light at greater than about 500 nm, renders these biosensor molecules particularly well-suited for detecting and measuring in-vivo glucose concentrations.

The invention relates to the technical field of a biosensor, and particularly relates to a fluorescence biosensor for detecting UDG (Uracil-DNA Glycosylase) on the basis of a polymerase-assisted feedback rolling circle amplification and endonuclease amplification fluorescence method. The invention aims to solve problems of both low specificity and low sensitivity of a method for detecting UDG in the prior art. The biosensor for detecting the UDG on the basis of a feedback rolling circle amplification technology achieves a rolling circle amplification effect on matching of phi29 polymerase andendonuclease IV, implements fluorescence resonance energy transfer of a fluorophore and a Quenching group and performs a homogeneous reaction on mixed liquid. A preparation method comprises: constructing a circular template and a composite probe; feeding back a rolling circle amplification signal and carrying out fluorescence detection. Specific hydrolysis of the UDG on a basic group U is utilized, and by utilizing such specific reaction, the UDG can be accurately measured and meanwhile, interference can also be avoided; by utilizing endonuclease IV circle amplification, a signal amplificationeffect is achieved.

The invention provides a fluorescent biological sensor for detecting uracil-DNA glycosylase (UDG). The fluorescent biological sensor comprises an annular template, a hairpin probe, a fluorescent probe, dNTP, phi 29 DNA polymerase and endonuclease IV. The biological sensor disclosed by the invention has the advantages of good specificity, high flexibility, moderate reaction condition and quick reaction speed; by means of silver cluster fluorescent detection, the biological sensor has the advantages of convenience in operation, short detection period, easiness in carrying, low technological cost, suitability for an industrial inexpensive requirement; a preparation method has the advantages of simpleness, stable performance and good repeatability.

The invention relates to a method for preparing an acetylcholinesterase fluorescence biosensor. The invention solves the following problems: the existing enzyme biosensor is prone to being affected by environmental influence so that the enzyme losses activity thus resulting false- positive; the existing biosensor is not allowed for repeated use due to irreversible reactions, in which enzymes are expensive, so that the cost of the equipment is excessively high; the selectivity is low, etc. The method comprises the following steps: firstly, carrying out the extraction separation and purification on acetylcholinesterase in crucian carp brain; then, carrying out the immobilization on the acetylcholinesterase in the crucian carp brain by chitosan; preparing immobilized acetylcholinesterase membranes, namely, obtaining the acetylcholinesterase fluorescence biosensor. The acetylcholinesterase fluorescence biosensor prepared by the invention dispenses with neither external power connection nor reference electrodes, and has the advantages of small size, light weight, high response speed, electromagnetic interference resistance, corrosion resistance, high sensitivity, wide measurement bandwidth, convenient operation, low cost and the like, therefore, the invention is applicable to the rapid detection of organophosphorus pesticide in food.

The invention discloses a bovine serum albumin-stabilized copper nano-cluster fluorescence biosensor and a preparation method and application thereof. The preparation method mainly comprises the step of preparation of a bovine serum albumin-stabilized copper nano-cluster; the fluorescence biosensor is used for sensitivity detection on hydrogen peroxide. According to a preparation method of the bovine serum albumin-stabilized copper nano-cluster, the copper nano-cluster with the fluorescence property is prepared by taking bovine serum albumin as a stabilizing agent and taking a copper sulphate solution as a copper source. The preparation method of the fluorescence copper nano-cluster is simple and low in cost and does not need any reducing agents, the prepared fluorescence copper nano-cluster has the advantages of being low in toxicity, good in light stability, high in quantum yield, good in biocompatibility and the like, and high sensitivity determination on hydrogen peroxide can be achieved through the copper nano-cluster. The copper nano-cluster has the wide application prospect in the fields of food safety, biochemical analysis, cell imaging, clinical diagnosis and the like by serving as a fluorescence probe.

The invention belongs to the technical field of biosensors and particularly relates to a miRNA detection fluorescent biological probe, a miRNA detection fluorescent sensor and application thereof anda miRNA detection method. In adoption of the probe for miRNA detection, steps are simple, marking is avoided, reaction is carried out in isothermal homogeneous solution, and problems of a complex separation process and high-time-consumption thermal cycle are avoided; a catalytic hairpin assembly technique and a lambda exonuclease (lambda-Exo) auxiliary signal amplification technique are ingeniously combined; by combination with DNA silver nano-clusters (DNA-AgNCs), high-sensitivity detection of biological targets is realized, the limit of detection reaches 0.89fM minimally, single base difference among miRNA family members can be distinguished, high specificity is realized, and the problem that a miRNA detection method in the prior art fails to achieve quickness, simplicity and low cost aswell as high detection sensitivity and high specificity.

The invention provides a fluorescent biosensor based on high-gradient magnetic separation and a quantum point as well as application thereof. The fluorescent biosensor comprises a high-gradient magnetic separation device and a fluorescence detection system; the high-gradient magnetic separation device comprises an annular magnet array, a magnet bracket, a ring channel and an iron bead chain; the annular magnet array and the magnet bracket form an annular magnetic field generator; every two adjacent magnets are mutually repulsed and assembled; two capillary tubes are coaxially fixed and then are nested in the concentric circle of the annular magnet array; the inner capillary tube is filled with the iron bead chain made of a soft magnet material; the iron bead chain can be magnetized by thering magnetic field, so that nanometer magnetic beads are distributed in the ring channel uniformly and are used for capturing a target object. The fluorescent biosensor provided by the invention canbe used for quantitatively detecting microorganisms, is simple to operate, high in separation efficiency and high in sensitivity, and can realize quantitative detection on a small amount of target bacteria in food samples within 2 hours.

The invention discloses a fluorescent material capable of visual detection of ammonia gas as well as a preparation method and an application of the fluorescent material, and belongs to the field of fluorescent biosensors. The fluorescent material is of a 1-(4'-carboxylic biphenyl)-2,5-diphenyl pyrrole (abbreviated as CP-TPP) film material, and is formed after the natural volatilization of a CP-TPP solution taken as a solvent which is dropwise smeared on a quartz plate. The fluorescent material which belongs to a solid film material is convenient to carry, has a specific response to the ammonia gas so as to rapidly detect the ammonia gas, and is high in sensitivity and selectivity. The preparation method is simple, convenient to operate and low in cost. The fluorescent material is simple to operate and obvious in effect during the detection of the ammonia gas, can be recycled and can be completely independent of a high precision instrument according to actual needs, thereby meeting the requirement of modern people on ammonia gas detection to a large extent.

The invention relates to a preparation method of a chitosan 6-OH immobilized cyclodextrin derivative, and an application thereof in a H2O2 detection fluorescent biosensor. The invention belongs to the field of high-molecular material preparation and modification. According to the invention, chitosan 2-NH2 is protected by using phthalic anhydride; through a click chemical reaction, cyclodextrin is immobilized at a 6-OH position; and the protection of chitosan 2-NH2 is removed by using hydrazine hydrate, such that the chitosan 6-OH immobilized cyclodextrin derivative with good solubility in water and part of organic solvents and with high immobilization rate is prepared. Fluorescent probe is immobilized in cyclodextrin hydrophobic hollow cavities of the chitosan 6-OH immobilized cyclodextrin derivative provided by the invention, 2-NH2 of chitosan pyranose ring is used for immobilizing catalase, and the material is used in a fluorescent biosensor used for detecting H2O2 content. The invention assists in realizing the application of chitosan 6-OH immobilized cyclodextrin derivative in the fluorescent biosensor in which enzyme catalysis is combined with fluorescence detection.

The invention belongs to the field of sensors, and particularly relates to a fluorescence biosensor for vascular endothelial growth factor detection in breast cancer. The fluorescence biosensor comprises nitrogen carbide nanometer materials, silver ions and a DNA probe. The gene of the DNA probe is 5'-CCCCCCTGTGGGGGTGGACGGGCCGGGTAGACCCCCC-3'. The silver ions and the DNA probe form a hairpin structure. Under the induction of a target molecule vascular endothelial growth factor, the NDA probe and target molecules are combined to form G-quadruplex structure, the silver ions are released, and fluorescence signals of the nitrogen carbide nanometer materials are quenched. When the fluorescence biosensor is used for early diagnosis of breast cancer, the detection limit of the fluorescence biosensor to the vascular endothelial growth factor is 3.5 pmol/L. When the fluorescence biosensor is used for clinical application, detection is more is more accurate, more sensitive, more economical, easier, more convenient and noninvasive, and the fluorescence biosensor is of great significance.

The invention discloses a fluorescent reagent for detecting trace serum albumin, and a preparation and application of the fluorescent reagent, and belongs to the field of fluorescent bio-sensors. The fluorescent reagent is prepared from DP-TPPNa and a good solvent. The preparation method comprises the following steps: dissolving 3,4-dibromo-1,2,5-tri((methoxycarbonyl)phenyl) pyrrole in the good solvent, adding phenylboronic acid, a catalyst and basic salt, and reacting to obtain DP-TPP; dissolving the DP-TPP in a solvent, adding alkali, and reacting to obtain DP-TPPNa; and dissolving the DP-TPPNa in the good solvent to obtain the fluorescent reagent. The fluorescent reagent is capable of quantitatively detecting the serum albumin in serum, is simple in preparation method, convenient to operate and quick in response, has high sensitivity and high selectivity, is capable of producing an excellent visible detection signal, can completely get rid of the dependence on high-precision instruments according to actual requirements, and can meet the requirement of people on detecting the serum albumin in serum today.

The invention relates to the technical field of biosensor, in particular to a fluorescence biosensor based on amplification of a hybridization chain reaction. The problems that the specificity and sensitivity of the method for detecting the kanamycin is low, and the cost is high in the above prior art are solved. According to the fluorescence biosensor based on the amplification of the hybridization chain reaction, the cyclic amplification effect is achieved through the hybridization chain reaction between the endonuclease IV and the chain. The mixture is reacted homogeneously by fluorescenceresonance energy transfer of the fluorophores and the quenching group. The preparation method comprises the following steps of: preparing gold nanoparticles; modifying Walker and Track to the surfaceof gold nanoparticles; mixing the labeled gold nano solution with the homogeneous reaction solution; performing hybridization chain reaction, and detecting the fluorescence; using the specific recognition of the nucleic acid Aptamer, using the nucleic acid Aptamer for high specific detection of the target kanamycin; and using the amplification of the hybridization chain reaction to achieve signalamplification.

The invention provides a time resolution fluorescent biosensor based on a phosphorescent light emitting technology and an application thereof. The time resolution fluorescent biosensor based on the phosphorescent light emitting technology comprises an exciting light path module, a photoelectric signal receiving and converting module, a control system module, an amplifying and shaping circuit, a coding interface circuit and a data cache module. The exciting light path module comprises a main detection exciting light module and an auxiliary optical scanning module. The photoelectric signal receiving and converting module comprises a main detection photoelectric conversion module and an auxiliary scanning photoelectric conversion module. According to the invention, a phosphorescent light emitting material (platinum/palladium porphyrin) is used as a biological marker, and the result is represented in form of an infrared optical signal under green light irradiation and can be interpreted by an instrument so as to quantitively detect a target object to be detected. According to the invention, a chromatographic test strip is divided into a sandwich method mode, a competition law mode, an indirect method mode and a capturing method mode to qualitatively and quantitively detect and analyze different objects to be detected in a sample quickly and sensitively according to different immunoreactions of the objects to be detected.

The invention relates to the technical field of biosensors, in particular to a fluorescent biosensor for detecting triphosadenine based on rolling circle amplification and incision enzyme feedback amplification. The biosensor comprises two aptamer DNA sequences, a linear padlock probe, a connecting probe, an AP probe, a T4 DNA ligase buffer solution, exonuclease I, exonuclease III, a PBS buffer solution, dNTP, phi29 DNA polymerase and endonuclease IV. A preparation method of the fluorescent biosensor comprises the following steps: (1) constructing an annular template to prepare a compound probe; and (2) combining a compound probe with an incision enzyme and a target object to achieve signal amplification. The probe can be used for achieving detection of high specificity and ultra-sensitivity. The fluorescent biosensor is mild in reaction, fast to detect and good in repeatability.

The invention provides a new nano fluorescence biosensor with a biological release control function as well as a preparation method and application thereof, wherein gold nano particles are used as an orifice cap of a gold nano cage. The sensor has the following characteristics: a DNA hybridization technology is adopted, and the gold nano particles are assembled on the surface of the gold nano cage to form an orifice cap switch to realize blocking of matters in the gold nano cage. The nano biosensor provided by the invention has the characteristics of simple structure, sensitive signal, strong controllability and the like. By adopting the nano fluorescence biosensor provided by the invention, high-sensitivity detection of ATP can be realized in a range of 1.0*10<-9>-1.0*10<-7>M; and the nano fluorescence biosensor has the advantages of sensitivity, economy, easiness in operation and the like, gains relatively great application potential and broad application prospects in the fields such as biomedicine and life science, and provides a new way and method for early diagnosis and treatment of serious diseases and particularly for the study and application of tumor-targeted drugs and photo-thermal therapy based on the nano carrier release control technology.

The invention relates to the technical field of biosensors, especially relates to a fluorescent biosensor based on hybrid chain reaction amplification, and solves the problems in the prior art that the method for detecting ampicillin is low in specificity and sensitivity, and the cost is high. According to a biosensor for detecting the ampicillin based on an aptamer, a cyclic amplification effectis realized by the cooperation of Nb.BbcCI and a chain hybrid chain reaction, and Thioflavine-T and G-quadruplex are combined to generate fluorescence and a homogeneous reaction mixed solution. The preparation method comprises the following steps of preparing gold nanoparticles; modifying Walker and Track to the surfaces of the gold nanoparticles; mixing a labeled nanogold solution with the homogeneous reaction solution; performing hyperbranched hybrid chain reaction and fluorescent detection; carrying out high specificity detection on the target ampicillin by using the aptamer by utilizing the specific recognition of the aptamer; and using hyperbranched hybrid chain reaction amplification to achieve signal amplification.

The invention discloses a fluorescent probe for targeting detection and cancer cell inhibition and its preparation method and use, and belongs to the field of fluorescent biosensors. The fluorescent probe is a 1,4-tetraarylbutadiene derivative containing 4, 4', 4''-di-4-difluoro-4-borata-3a-azonia-4a-aza-s-indacene (BODIPY). The preparation method comprises that 4,4'-((1E, 3E)-1,4-dibromo-1,3-butadienyl-1,4-dily)dibenzaldehyde (or methyl 4,4'-((1E, 3E)-1,4-dibromo-1,3-butadienyl-1,4-diyl)dibenzoate) and BODIPY pinacol ester undergo a Suzuki reaction in the presence of a tetrakis(triphenylphosphine)palladium as a catalyst to produce the fluorescent probe or BODIPY-DICHO and a biomolecule undergo a one-step Schiff base reaction to produce the fluorescent probe. The preparation method has simple processes and is convenient for operation. The fluorescent probe has functions of targeting marking and cancer cell inhibition and can be used as a latent anticancer drug.

The invention relates to the technical field of biosensors, and particularly relates to a fluorescent biosensor for detecting ochratoxin A based on a rolling ring amplification mediated catalytic hairpin self-assembly and incision enzyme feedback amplification method. According to the fluorescent biosensor, as for a detection mode, a fluorescence method is adopted for detection, and a luminoscopeis utilized; before detection, a padlock probe and a connecting probe form an annular template probe; then a target object is added to a homogeneous solution of a complex probe I, a complex probe II,HP 2 and HP 3, incubating is carried out for 120 minutes at 37 DEG C, and the target object and an aptamer sequence are bound; the multiple feedback amplification process is completed under the actionof a phi29 DNA polymerase and an endonuclease IV, so that signal amplification is realized; and then, the luminoscope is used for setting the excitation wavelength to be 399 nm, the fluorescence intensity at 610 nm is detected, and the detection range is 560-640 nm. Meanwhile, the invention further provides a preparation method for the biosensor. The preparation method has the advantages of beingmild in reaction condition and easy to operate.

The invention relates to a composite fluorescent biosensor, and a preparation method and an application thereof. The composite fluorescent biosensor comprises a graphene quantum dot and a carboxymethyl cellulose-chitosan polyelectrolyte microsphere; and the carboxymethyl cellulose-chitosan polyelectrolyte microsphere is a microsphere having a core-shell structure, the core is made of melamine andformaldehyde, and the shell is made of chitosan and carboxymethyl cellulose. The preparation method of the organic-inorganic composite fluorescent biosensor and a fluorescence detection method of target biological polysaccharides are helpful for improving other biological sensors. The composite fluorescent biosensor formed by cellulose ether-based polyelectrolyte microsphere induced graphene quantum dot aggregation has a very good market prospect and very good industrial production values.