291 results about "Molecular fluorescence" patented technology

The present invention is directed to optical structures and methods detecting the fluorescence of a molecule using metal-enhanced fluorescence. In particular, the invention describes the use of surface plasmon excitation for excitation of fluorophores near the metal surface and the efficient collection of the emission by coupling into the plasmon resonance and directing towards the detector. More particularly, the present invention makes use of the unique directionality of the plasmon induced fluorescence signal. The present invention is directed to optical structures using metal enhanced fluorescence including: an optical fiber having a conductive external coating; a light emitting diode (LED) having a conical shaped depression with curved sides on a front end surface, the curved sides having a conducting coating on the outer surface with respect to the LED.

The invention provides a fluorescent probe represented by the formula (I), wherein R1 and R2 are independently selected from H or an aromatic vinyl group, and at least one of R1 and R2 is the aromatic vinyl group; R3 is selected from H, F, Cl, Br, OH, OCH3, N(CH3)2 or C1-C6 alkyl; and R4 is selected from C1-C6 alkyl. Compared with the prior art, because the fluorescent probe provided by the invention has a relatively large electronic conjugated system and plane, the intensity of the intramolecular charge transfer effect can affect the molecular fluorescence emission intensity; when the fluorescent probe and the G-quadruplex generate a specific action, the flexibility of intramolecular rotatable double bonds is restricted, the intramolecular charge transfer effect is enhanced, and the fluorescence is also enhanced significantly; moreover, the fluorescent probe provided by the invention has the advantages of low biotoxicity, phototoxicity and photobleaching property, good light stability, good water solubility and good cell membrane permeability.

The invention discloses a preparation method of molecularly imprinted polymeric microspheres for 2,4,6-trinitrophenol detection. The preparation method is characterized in that polynitrophenol derivatives-imprinted molecules generated through reaction between 2,4,6-trinitrophenol and N,N'-diisopropyl carbodiimide have luminous yellow fluorescent light, the fluorescent light of the imprinted molecules has open and close characteristics under an acid-base condition, the imprinted molecules located in an imprinting layer of the molecularly imprinted polymeric microspheres can be eluted, a hole structure which is complementary with the structure, the size and the functional groups of the imprinted molecules is formed in the imprinting layer, polymeric microspheres of which the imprinted molecules are eluted have specific recognition sites on target analyte molecules, target molecules enter the specific recognition sites, selective recognition on the target analyte molecules is realized, sensitivity detection of the target analyte molecules can be realized through opening and closing of the fluorescent light of the target molecules, the specific surface area of the molecularly imprintedmicrospheres is large, and space in which the recognition sites are formed is stable in structure, has more effective sites, and is capable of carrying out high-selective recognition and high-sensitive detection on the target molecules.

The invention provides a pillar[5]arene and 2-hydroxy-3-naphthoic acid complex.Copolymerized pillar[5]arene serves as a subject, 2-hydroxy-3-naphthoic acid serves as an object, C-H......pi and electrostatic attraction serve as driving force, partial 2-hydroxy-3-naphthoic acid provided with negative charges is included into a cavity of pillararene in an alkaline environment, the assembling process of the subject and the object is completed, and the stable pillar[5]arene and 2-hydroxy-3-naphthoic acid complex is formed.Iron ions are added to an alkaline aqueous solution of the complex, and the subject and the object are subjected to fluorescence quenching; fluorine ions are added, a complex is formed by the fluorine ions and the iron ions, so that the iron ions are separated from the cavity of copolymerized pillar[5]arene, and molecular fluorescence of the complex is reopened.Therefore, Fe<3+> can be determined through the pillar[5]arene and 2-hydroxy-3-naphthoic acid complex, and F<-> can be continuously identified through fluorescence quenching of the solution.

The invention provides a near infrared BODIPY (Boron Dipyrromethene) compound-based molecular fluorescence probe which has the following structure, wherein the substituent group Ar is one of the following four substituent groups described in the specification. The BODIPY probe with an alpha bit containing a strong electrondrawing group is synthesized for the first time, the absorption spectrum red shift of the fluorescence probe can achieve 606-633nm through the introduced substituent group, and the emission peak can achieve 616-646nm. The BODIPY molecule is a favorable fluorescence, can be used for specifically marking lysosome in biological cells, and can emit light through the self molecules, and the absorption and emission of the BODIPY molecule are close to the near-infrared zone; and in addition, the fluorescence probe has the advantages of high mole extinction coefficient, acute emission peak, high fluorescence quantum yield and the like, and has attractive application prospects on the lysosome marking application.

The invention discloses macromolecular fluorescent microspheres and a preparation method thereof. The macromolecular fluorescent microspheres use monodisperse sulfonated polystyrene microspheres as core microspheres, and the surfaces of the macromolecular fluorescent microspheres are coated with a shell layer of a p-phenylene vinylene (PPV) fluorescent conjugated macromolecular polymer. The preparation method of the macromolecular fluorescent microspheres comprises the following steps of: synthesizing a positively charged PPV fluorescent conjugated macromolecular polymer precursor in solution by using a Wessling sulfosalt polymer precursor method; adding the monodisperse sulfonated polystyrene microspheres into the precursor, and then processing the mixture for 0.5 to 2 hours under a vacuum condition that the temperature is between 90 and 150 DEG C; and washing and drying the mixture to obtain PPV conjugated macromolecular fluorescent microspheres. An inhomogeneous reaction for synthesizing the conjugated polymer in the method is simple and controllable, and the stability of the fluorescence of the microspheres is effectively improved.

The invention discloses a Fe<3+> molecular fluorescence sensor based on Rhodamine B and a preparation method and application of the Fe<3+> molecular fluorescence sensor. Rhodamine B is taken as a precursor, and a target product N1-(benzene[d] thiazole-2-yl)-N4-(2-(3',6'-bi(diethylin)-3-carbonyl screw[iso-indoline-1,9'-xanthene]-2-yl)ethyl) maleimide is synthesized at two steps. Detection on Fe<3+> by using the target product shows that the target product has a very good detection effect on Fe<3+>; and meanwhile the raw materials of the Fe<3+> molecular fluorescence sensor are easy to obtain, synthesis steps are simple, after-treatment is convenient to implement, and large-scale production can be relatively easily achieved.

Provided is a method of producing a polymeric fluorescent substance wherein one or more monomers represented by the general formula (1) are polymerized in the presence of a zerovalent nickel complex,X1—Ar1—X2  (1)wherein, Ar1 represents a divalent group selected from the group consisting of arylene groups, divalent heterocyclic compound groups, and divalent or trivalent hetero atom-bonded arylene or divalent heterocyclic compound groups, and X1 and X2 represent leaving groups. By using the polymeric fluorescent substance, a high performance polymer LED can easily be obtained.

The invention discloses a substituted Rhodamine B acylthiosemicarbazide fluorescence probe compound and a preparation method and application thereof, and belongs to the technical field of synthesis of fluorescence probe compounds. According to the technical scheme, the substituted Rhodamine B acylthiosemicarbazide fluorescence probe compound has a chemical structural formula (please see the formula in the description), wherein R is Cl or OMe or CF3. The invention further discloses the preparation method of the substituted Rhodamine B acylthiosemicarbazide fluorescence probe compound and application of the substituted Rhodamine B acylthiosemicarbazide fluorescence probe compound serving as an organic molecular fluorescence probe for detecting heavy metal mercury ions. The fluorescence probe compound shows the good antijamming capability, can accurately detect a trace quantity of heavy metal mercury ions and is good in selectivity and sensitivity.

The invention discloses a method for fast optical tracking of a single molecule and a device, and relates to a technology for detecting single-molecule fluorescence spectroscopy and signal processing.The method uses the single-photon detection technology for detecting molecular fluorescence, analyzes the detected position with strongest fluorescence strength for determining the position of the single molecule, controls a nano-translation stage by feedback of a computer for tracking the position of the molecule and realizes the fast tracking of the motion trajectory of the molecule. The methodadopts the low-frequency sine wave modulation for triggering a laser signal of a single-molecule sample, thereby improving the signal-to-noise ratio. Compared with the prior art, the method adopts the single-photon detection technology, thereby being capable of determining and fast tracking the position of the single molecule in a relatively fine manner; the central position of the optoelectronicfeedback control nano-translation stage is changed along with the position of the single molecule, thereby being capable of reflecting the motion trajectory of the single molecule in a real-time manner; and the use of the modulation and demodulation technology can effectively suppresses the impacts of background noise on the detection of a fluorescence signal of the single molecule.

The invention provides a measuring method for the diffusion motion trail of a single molecular chain in a thin polymer film, which comprises the following steps: 1) connecting fluorescence probe molecules to the long chain tail end of the polymer to be measured to obtain a fluorescence labeling polymer; 2) blending the fluorescence labeling polymer into the unlabelled polymer to be measured and preparing a thin polymer film sample; 3) irradiating continuous laser to the sample to obtain the fluorescence which is emitted by the fluorescence labeling polymer; and 4) focusing and imaging the fluorescence to obtain the continuous single molecular images of the fluorescence labeling polymer and connecting the continuous single molecular images of the fluorescence labeling polymer along with different time to obtain the diffusion motion trail of the single molecular chain in the thin polymer film. The measuring method provided by the invention utilizes a single molecular fluorescence imaging technique and has the sensitivity at the single molecular level.

The invention relates to a measurement system for obtaining a single molecular spectrum and imaging under a shear field, characterized in that the measurement system includes: an excitation light source unit used as excitation light to irradiate a sample to be tested; a unit for applying a mechanical A shear application and rheological measurement unit for simultaneously measuring its macroscopic rheological properties; and an optical microscopic unit, the optical microscopic unit is used to introduce the excitation light emitted by the excitation light source unit into the waiting area under the shear field. The sample is measured, so that the dye molecules of the sample to be tested are excited to generate fluorescent signals, and the generated fluorescent signals are collected and respectively transmitted to a single-molecule fluorescence imaging unit, a single-molecule fluorescence emission spectrum measurement unit and / or a fluorescence correlation spectrum measurement unit . The invention can be widely applied to polyelectrolyte dilute solution, gel, interfacial diffusion, film imaging and other multi-charge condensed state systems, and explores the basic physical origin of its special properties.

The invention discloses a synthesis method of a spiropyrane small-molecule fluorescent probe with extreme acid / extreme alkaline switch response and an application of the spiropyrane small-molecule fluorescent probe. By virtue of the synthesis method, naphthalene nucleus spiropyrane with two carboxyl groups and a phenolic hydroxyl group is synthesized by carrying out modification on three loca of spiropyrane, wherein the naphthalene nucleus spiropyrane has the characteristic of reversible switch type response on pH values of extreme acid / extreme alkaline; when the pH value is smaller than 1.0, red fluorescence is represented; when the pH value is 1.0-12.0, fluorescence is represented; when the pH value is greater than 12.0, blue-green fluorescence is represented. The synthesized spiropyrane small-molecule fluorescent probe also has the characteristics of being high in optical, thermal and chemical stability and structural designability, and excellent in biocompatibility and cell labeling property; meanwhile, the synthesized spiropyrane small-molecule fluorescent probe is safe and low in low toxicity, and is capable of smoothly entering bacteria for bio-labeling, implementing the pH response of extreme acid / extreme alkaline as same as that of solutions in organisms; furthermore, the synthesized spiropyrane small-molecule fluorescent probe can be used as a multifunctional cell fluorescence labeling dye and can be applied to scientific research and gene diagnosis in the field of biological medicines.

The invention discloses a xanthene fluorescent dye molecular fluorescent probe. Under different acid and alkali conditions, a fluorescent dye is transformed between isomers of a single loop coil open loop and a double-loop coil open loop, and the structure transformation ensures that a conjugated system of the dye is changed, and the color of a corresponding solution, the wavelengths for absorption and emission peaks and the fluorescence intensity are changed; and a xanthene fluorescent dye is used for preparing a xanthene fluorescent dye esterification derivative which can be used as a fluorescent molecular probe material to realize fluorescent detection of NADH. The xanthene fluorescent dye molecular fluorescent probe disclosed by the invention has the advantages that the molecular fluorescent probe has a double-loop coil hexatomic ring condensing system, the release of optical signals of the dye is controlled by the double-loop coil structure, and a switch of the loop coil structure is used for adjusting and controlling a fluorophore xanthene conjugated system in the whole molecular structure, and widening the adsorption and emission wavelengths of the conjugated system to ensure that the optical signal intensity is changed correspondingly; and the probe material is quick in response to NADH, high in selectivity and good in biological membrane permeability, and a preparation method of the probe material is simple and feasible, low in cost and obvious in economic and technical effects.

A method for generating same-beam dual-wavelength dual-pulse laser uses a tunable laser crystal suitable for flash-lamp pump to obtain Q-regulating pulse output, and can be used for pollution measuring radar, holographic molecular fluorescence diagnosis, satellite range finding, etc. A photoelectric switch device is used to make the laser oscillate sequentially in the sub-cavities of two channels during a pump pulse. As their oscillating wavelengthes are different, there is dual-wavelength dual-pulse output.

The invention relates to a xanthene fluorescence dye, a preparation method and applications thereof, wherein the fluorescence dye is 3',3''-bis(oxospiroisobenzofuran)-3-hydroxy-7-(diethylamino)benzopyran-xanthene. According to the present invention, the xanthene fluorescence dye is designed and synthesized, the dye has the double-spiro six-membered ring fused system, the optical signal release of the dye is controlled by the double-spiro structure, the opening / closing of the spiro structure regulates the fluorophore xanthene conjugation system (the quinone type system forms or disappears) in the whole molecular structure, and the absorption wavelength and the emission wavelength are expanded so as to make the optical signal intensity accordingly change; and the isothiocyanate derivative molecule fluorescence probe synthesized through further derivatization provides characteristics of rapid response, high selectivity, high detection sensitivity and low detection limitation on Hg<2+>. In summary, the present invention provides the xanthene fluorescence dye design synthesis method, and the dye is adopted to design the Hg<2+> detecting molecule fluorescence probe for the optical signal report gene.

The invention discloses a tumor-targeted diagnosis and treatment integrated fluorescent probe which takes a tumor-targeted polypeptide sequence and an apoptosis enzyme specific recognition polypeptide sequence as a framework and comprises a fluorescence quenching molecular fluorescence pair and a photodynamic treatment photosensitizer. The diagnosis and treatment integrated fluorescent probe can achieve targeted treatment of tumors, and reduce toxic and side effects of the photodynamic treatment photosensitizer; a treatment result can be assessed in situ accurately in real time while the tumors are subjected to photodynamic treatment. The tumor-targeted diagnosis and treatment integrated fluorescent probe can also be used as a common fluorescent probe and used for screening of tumor treatment medicines and cell apoptosis imaging in a proportional fluorescence imaging manner. The tumor-targeted diagnosis and treatment integrated fluorescent probe can realize early detection of tumor treatment feedbacks and has great significance in promotion of accurate treatment of tumors and personal treatment.

The invention relates to a molecular fluorescent probe for detecting hypochlorite. The probe is tetrafluoborate of 2-)4-boronic phenyl vinyl)-N-alkyl quinoline. The preparation method comprises the following steps: 1) mixing iodine onium salt and 4-formyl borophenylic acid according to the molar ratio of 1:1, and counter-flowing for 6 hours in ethanol; 2) then adding KBF4 to counter-flow for 2 hours for anion exchange; and 3) using a purified product recrystallized by absolute ethyl alcohol. The molecular fluorescent probe provided by the invention has the advantages that the molecular fluorescent probe aiming at strong fluorescence enhancement effect of detection of hypochlorite in tap water can be applied to detecting hypochlorite in an environmental sample, tap water and chemical simulative biosystem, analysis and detection and fluorescence imaging detection of biological living cells and hypochlorite in living tissues as well as detection of hypochlorite in disease tissues in clinical medicine. The molecular fluorescent probe for detecting hypochlorite provided by the invention has the good effects of fast response speed, high selectivity, high sensitivity and strong practicality and the like.

The invention provides a method for quantitatively detecting salbutamol by using CdTe quantum dots. The method comprises the following steps: uniformly mixing the CdTe quantum dots with surfaces modified by mercaptoacetic acid with a substance to be detected, namely salbutamol, in a phosphate buffer solution, and then detecting fluorescent strength of a system by adopting a molecular fluorometer to realize trace detection of salbutamol because that in a weakly alkaline solution system, the CdTe quantum dots with the surfaces modified with carboxyl groups having negative charges and target molecules having positive charges, namely salbutamol, form a new compound system through electrostatic interaction so as to cause fluorescence quenching. Detection results show that salbutamol has relatively high sensitivity and a relatively wide linear range against the fluorescence quenching of the CeTe quantum dots, so that the changes in the fluorescent strength of the CdTe quantum dots are used for realizing the quantitative detection of salbutamol; and furthermore, the method for quantitatively detecting salbutamol by using the CdTe quantum dots, provided by the invention, is very simple in experimental operation, the detection time is short and the analysis cost is low.

The invention relates to a method for detecting the content of phenylethanolamine A by utilizing a CdTe quantum dot. The method takes mercaptopropionic acid as a stabilizer; the CdTe quantum dot prepared by a microwave radiation heating method is used as a fluorescent probe; and the method for detecting the content of the phenylethanolamine A is established based on a fluorescent intensity enhancing effect on the CdTe quantum dot by the phenylethanolamine A. The method comprises the following steps: uniformly mixing the CdTe quantum dot with the phenylethanolamine A of a substance to be detected in a phosphate buffering solution; standing for 15 minutes; and detecting the fluorescent intensity of a system by adopting a molecular fluorescence photometer so as to realize trace detection of the phenylethanolamine A. The method has the advantages of high detection sensitivity, simplicity and convenience for operation, short detection time, low analysis cost, relatively low detection limit and relatively high standard recovery rate.

The invention relates to a phenothiazinyl quinazoline fluorescence ion probe and application thereof. A fluorescence chemical sensor is based on a phenothiazinyl-substituted quinazoline derivative, and the structural general formula of the derivative is shown as a formula (1), wherein R1 is a hydrogen atom, alkyl which contains 1 to 10 carbon atoms, ether, azyl, aliphatic amide, imide, an ester group, an aryl substituent group or a hybrid aryl substituent group. Compared with other macromolecule fluorescence probe molecules, the fluorescence ion probe has the characteristics of simplicity in dissolution and synthesis and the like, and good response and identification effects on Cu<2+>, and also has a good identification effect on Hg<2+> in the presence of Cu<2+>, and generates different fluorescence responses to Hg<2+> and Cu<2+> under different conditions, multifunctionality on ion detection, and can also be designed into ion light introducing or fluorescence inhibit (INH) logic gate.

The invention discloses a preparation method of a high-molecular fluorescent microsphere. The method includes following steps: dispersing 1 part by weight of polystyrene microspheres in 0.1-1 ml of ultrapure water; adding dropwisely the polystyrene microsphere aqueous dispersion to 3-10 ml of a polydiallyldimethylamine hydrochloride solution with a concentration being 1.0-4.0 mg / ml with stirring; continuously stirring the solution for 1-4 h; performing centrifugation and removing a supernate; performing a washing process through ultrapure water; performing a centrifugation and collecting precipitate; vibratingly dispersing the precipitate in 1-2 ml of ultrapure water; adding dropwisely the polystyrene microsphere aqueous dispersion to 5-50 ml of a marked or an unmarked polysaccharide-type polyelectrolyte macromolecule solution with a concentration being 1.0-6.0 mg / ml with stirring; continuously stirring the solution for 1-4 h; performing centrifugation and removing a supernate; dispersing a precipitate in pure water; performing a centrifugation and collecting precipitate; and dispersing the precipitate in ultrapure water to obtain polysaccharide-modified fluorescent microsphere. The high-molecular fluorescent microsphere is 1-10 [mu]m in particle size, is 350-800 nm in fluorescent excitation wavelength, and has excellent biocompatibility and stability.

A system and method is disclosed wherein optical signals are coded in a transmitter by tuning or modulating the interbeam delay time (which modulates the fourth-order coherence) between pairs of entangled photons. The photon pairs are either absorbed or not absorbed (transparent) by an atomic or molecular fluorescer in a receiver, depending on the inter-beam delay that is introduced in the entangled photon pairs. Upon the absorption, corresponding fluorescent optical emissions follow at a certain wavelength, which are then detected by a photon detector. The advantage of the disclosed system is that it eliminates a need of a coincidence counter to realize the entanglement-based secure optical communications because the absorber acts as a coincidence counter for entangled photon pairs.

The invention relates to a fluorescence spectrum imaging technique, aiming at solving the problem of fuzzy single-molecule fluorescence imaging arising from the fluctuation in molecular fluorescent radiation and lower signal-to-noise ratio. The invention provides a method and device for improving the definition of single-molecule fluorescence imaging. The method comprises the following steps of: scanning and irradiating a single-molecule sample by using laser which is subjected to intensity modulation by an acousto-optic modulator; receiving fluorescent photons emitted by the single-molecule sample and converting the fluorescent photons into a standard logic electrical pulse output signal by using a single-photon detector; inputting the logic electrical pulse output signal to a lock-in amplifier, meanwhile, inputting a synchronous sine waveform modulated voltage signal to the lock-in amplifier; and demodulating the logic electrical pulse output signal to obtain a detected fluorescence spectrum signal and imaging the fluorescence spectrum signal. According to the invention, the intensity modulation to the single-molecule fluorescent photons is achieved by using an intensity modulated excitation light field, the quantum fluctuation in photon counting is eliminated by using analog signals demodulated by the lock-in amplifier, the signal-to-noise ratio is increased, and therefore, the high-definition single-molecule fluorescence imaging is achieved.

Provided is the design, synthesis and applications of molecular fluorophores for bioimaging in the short wavelength infrared window (1000-1700 nm). The molecular fluorophores compound comprise structures with electron accepting aromatic units, electron donating aromatic units, and an shielding units which shield the conjugated backbones from intermolecular interactions.

The invention relates to a fluorescence detection method for acetamiprid. The fluorescence detection method comprises the following steps: (S1) activating carbon quantum dots, equally dividing the carbon quantum dots into two parts, adding one part into a nucleic acid aptamer solution with a specific recognition effect to acetamiprid, adding the other part into a nucleic acid aptamer complementarychain solution, carrying out oscillation coupling, and mixing two solutions, so as to obtain carbon quantum dot mixed liquid; (S2) separating residual nucleic acid aptamers and complementary chains in the carbon quantum dot mixed liquid obtained in the step (S1) by virtue of an electrophoresis method, so as to obtain a complementary chain modified carbon quantum dot solution only containing the aptamers; and (S3) adding a to-be-tested acetamiprid sample into the carbon quantum dot liquid obtained in the step (S1), oscillating for reaction, and measuring the fluorescence intensity of the solution by virtue of a molecular fluorescence photometer. By modifying the carbon quantum dots with the nucleic acid aptamers with a specific recognition effect to acetamiprid and the complementary chainof the aptamers, a rapid and sensitive detection method for acetamiprid is established through the change of the fluorescence intensity of the carbon quantum dots before and after acetamiprid is added.

The invention discloses a tungstate upconversion luminescence temperature sensitive material doped with rare-earth elements Er and Yb and a preparation method thereof, and belongs to the technical field of a luminescence material. A general chemical formula of the luminescence material is MWO4: xEr, yYb, wherein x is more than or equal to 0.025mol% and less than or equal to 2.0mol%, x: y=1: 10 (molar ratio), and in the general formula, M is selected from one or more of Zn, Mg or Ba. The prepared luminescence material has good upconversion luminenscence performance, is high in luminous intensity, excellent in temperature sensitive performance, high in sensitivity and wide in application temperature area and has wide application prospect in the fields such as a fluorescent temperature sensor, a biological molecular fluorescence marker, infrared detection and anti-counterfeiting, three-dimensional display, solar battery and the like.

The invention relates to a rare-earth element-containing up-conversion luminescent temperature sensitive material as well as a preparation method and application thereof. The luminescent material has a general chemical formula of (A0.5Re0.5)TiO3, wherein A is selected from one or more of Rb, K, Na, Li and Ag, and Re is selected from one or more of Er, Yb, Pr, Eu, Ho, Tm, Tb and Dy. The sensitive material can be used for preparing the material provided by the invention, and the luminescent material prepared by the method provided by the invention has excellent up-conversion luminescent performance and temperature sensitivity, high luminescent intensity, good temperature sensitivity, a wide application temperature range, stable chemical performance and a controllable physical size, is easy to prepare, is relatively low in cost, and has a wide application prospect in the fields of fluorescent temperature sensors, short-wave emission solid lasers, biological molecular fluorescence labeling, infrared detection and anti-counterfeiting, three-dimensional display, photoelectric integrated devices, solar batteries and the like.