106 results about "Chemical signal" patented technology

The invention provides compositions and methods for signal activated RNA interference (saRNAi), preferably in vivo. The invention provides polynucleotides that switches between an inactive form and an active form upon covalent or non-covalent interaction with one or more specific chemical signals, such as disease-specific mRNA, miRNA, or other cellular RNA products with sequences that characterize diseased states of the cell. The interaction between the subject polynucleotides and the signals is preferably mediated by hybridization, which exposes, facilitates the formation, and/or allows the formation of a substrate that can be processed by proteins of the RNAi pathway (such as Dicer). The input and output of multiple different polynucleotides of the invention can form an in vivo signaling network. In addition, the multiple input signals can be integrated to modulate the activity of the subject polynucleotides.

The invention discloses an apparatus for growth of a cell colony. The apparatus provided by the invention comprises a micro graphical pattern template with a plurality of micro graphical cavities and a viscous hydrogel disposed under the micro graphical pattern template; the micro graphical pattern template and the viscous hydrogel are cross-linked and adhered into a whole; the shape and size of each micro graphical cavity determines a physical space of the growth of the cell colony. Materials used for the viscous hydrogel can be composed of a natural biomaterial and/or an artificially synthesized biomaterial capable of cross-linkedly forming the hydrogel and a cross-linking agent. A platform provided by the invention is simple in preparation process, is simple and practical for use matching with a culture dish. A plurality of co-culture environments are constructed by using the micro graphical technology, so that convenient and practical means are provided for construction and screening of high-throughput model; at the same time, independent control a plurality of factors such as the shape and size of the cell colony, mechanical strength and chemical components of an adhesive substrate, growth factors and chemical signals, co-culture cells and the like; and cell proliferation culture and induced differentiation culture can be carried out in-situ.

The invention relates to the field of preparation of an electrochemical immunosensor for rapid and sensitive detection of procalcitonin antigens, and in particular relates to a preparation method and application of a PCT electrochemical immunosensor based on AuNPs/Cu-MOF marking. AuNPs has a large specific surface area, has good conductibility and good biocompatibility, can capture many primary antibodies as a base material, and simultaneously can promote electron transfer; AuNPs/Cu-MOF marks secondary antibodies and can provide sensitive electrochemical signals; and according to the relationship between the intensity change of the electrochemical signals of AuNPs/Cu-MOF and the concentration of the antigens, rapid and sensitive detection of the procalcitonin antigens can be realized.

An electrochemical detection system which specifically detects selected nucleic acid segments is described. The system utilizes biological probes such as nucleic acid or peptide nucleic acid probes which are complementary to and specifically hybridize with selected nucleic acid segments in order to generate a measurable current when an amperometric potential is applied. The electrochemical signal can be quantified.

The invention discloses an electrochemical biosensor and a detecting method thereof. The sensor comprises a multi-channel chip electrode, an electrochemical detecting module and a control module, wherein the multi-channel chip electrode is used as the front end of the electrochemical biosensor and converts chemical signals into electric signals; the electrochemical detecting module comprises a signal conditioning circuit, an A/D (analog/digital) converter and an MCU (micro controller unit); the electrochemical detecting module generates a voltage and inputs the voltage into the chip electrode; the chip electrode generates the corresponding current; the current is converted into the voltage through the signal conditioning circuit; the voltage passes through the A/D converter to obtain the corresponding digital amount and then is processed by the MCU; and the control module is used for taking charge of controlling the testing process, realizing the real-time display, controlling the experiment process and receiving detection data. The invention has the advantages that the electrochemical biosensor is provided with a humanized touch screen type man-machine interaction interface and multiple detecting channels, can be independently used and can be connected with a PC (personal computer); the requirements of the multi-channel rapid detection in relativity and repeatability experiments can be met; and printing electrodes are used in place of the traditional electrodes and the electrochemical biosensor is more suitable for miniaturization.

The present invention provides novel tank circuits that are totally passive, and they are made of conductive-grade carbon nanotubes (CNTs) on substrates, and preferably flexible substrates. These components and structures contain no traditional electronic materials such as silicon, metal oxides, or ceramics, and they are totally organic. They may be used in applications where the resonant frequency and amplitude of the sensor can be modulated by a thermal, mechanical, or chemical signal, such as temperature, strain, pressure, vibration, or humidity. All-organic, and consequently combustible, passive RF sensors have unique applications for defense and consumer industries.

The present invention relates to a nano tip and a fabrication method of the nano tip that is generally usable in mechanical, physical, and electrical devices for detecting surface signals or chemical signals, or is usable for a source scanning energy beam. The fabrication method of a nano tip according to the present invention includes providing a supporting holder that is fixed at one end thereof to a mechanical or electrical device, bonding a carbon nanotube to the free end of the supporting holder, and modifying the property or the shape of the carbon nanotube by scanning an energy beam thereto. The nano tip, having improved stiffness and perpendicularity, is fabricated by adjusting the length, the diameter, and the shape of the end of the carbon nanotube tip attached with carbon nanotubes by means of the energy beam so that the nano tip may stably and repeatedly reproduce information of a sample and may minimize a deviation between the tips.

One or a combination of known chemical cues that attract pregnant female mosquitoes to an egg-laying site are embedded in a biodegradable carrier that releases the compound at a generally constant rate for up to a year or longer. The compound is useful for attracting large numbers of mosquito vectors to a site where they and their progeny can be eliminated.

The invention relates to a method for synergistic growth of multiple cells. The method is characterized by: using a hydrogel carrier prepared under physiological conditions to culture different cells in different carriers by means of embedding small carriers in large carriers, thus studying intercellular chemical signal transmission and interaction. The biggest advantages of the method lie in that: the carrier can contain one or over two different types of cells or tissues; non-direct contact spaces of different cells are provided; the growth of different cells or tissues in a three-dimensional environment is realized; biological effects are generated by chemical signal transmission among different cells; intercellular interaction generated effects can be investigated by crushing each carrier respectively to obtain different cells successively; and during actual application, the method is easy to realize recovery and scale-up.

The invention discloses a preparation method of a ratio electrochemical miR3123 aptamer sensor based on a Cu-MOF (copper-based metal organic framework) compound doped with BPNSs (black phosphorusnanosheets) and TH (thionine). The method comprises steps as follows: TH and a Cu-MOF precursor are subjected to a reaction for preparation of TH/Cu-MOF, and BPNSs/TH/Cu-MOF is prepared by drip coating ofthe BPNSs and applied to an electrode by drip coating; DNA single-stranded aptamers marked with Fc (ferrocene) are adsorbed on the BPNSs, and aptamer-BPNSs/TH/Cu-MOF is prepared; a target moleculemiR3123is bonded with the DNA single-stranded aptamers Fc-DNA, Fc-DNA is enabled to be separated from the BPNSs, and therefore, Fc electrochemical signals are weakened while TH signals are slightly affected; the ratio electrochemical miR3123aptamer sensor is constructed by fitting linear relation of current peak intensity ratio IFc/ITH and miR3123 concentration.

The invention relates to a poisonous and harmful gas detection chip and a preparation method thereof. For a chip detection system, a reaction microchannel, a fluid microchannel, an electrode microchannel and a microfluid driving region are processed on a microfluidic chip, so that the integration of a plurality of functional units is realized. An electrochemical oxidation/reduction reaction of poisonous and harmful gas is performed on the surface of an electrode slice embedded in the reaction microchannel; electrolysis is carried out to generate the change of an electrochemical signal; and an electrochemical detector obtains the type and concentration information of the analysed gas by analysing the change of the electrochemical signal.

The invention discloses a method and application for promoting cells to secrete exosomes, and relates to the fields of biological materials, tissue engineering and regenerative medicines. According tothe method, the cells are stimulated by active signals of a biological material, and the exosomes generated by the cells are collected, and are used for tissue wound treatment. The operation route ofthe method and the application scheme of the obtained exosomes are described in detail, under the stimulation effects of bioactive glass chemical signals, electrostatic spinning fiber membrane structure signals and chemical/structural combination signals, more exosome particles can be secreted by mesenchymal stem cells and umbilical vein endothelial cells, and the exosomes can promote the corresponding target cells to express higher levels of functional genes, secrete more multifunctional proteins and carry out deep functional differentiation, so that the tissue wound surface can be rapidly repaired. The exosomes obtained by the method disclosed by the invention have the characteristics of higher yield and stronger tissue repair promotion function.

The invention discloses a CFR-PEEK orthopedic implant, a preparation method thereof and a wireless sensing device. The carbon fiber reinforced polyether-ether-ketone orthopedic implant comprises a carbon fiber reinforced polyether-ether-ketone matrix and a patterned carbonized layer, and the patterned carbonized layer is formed by performing in-situ carbonization on the carbon fiber reinforced polyether-ether-ketone matrix. Therefore, a mechanical signal, a temperature signal or a chemical signal can be sensed by utilizing the patterned carbonized layer formed on the carbon fiber reinforced polyether-ether-ketone matrix in situ, the healing condition of an injured part can be detected and monitored in real time by combining an in-vitro probe or an in-vivo signal transduction device, and complications can be found in time; and operations and postoperative rehabilitation can be better guided.

The invention belongs to the technical field of biosensor detection, and relates to preparation method and application of a ratio sensor for streptomycin based on electrochemistry and photoelectrochemistry dual methods. Specifically, the novel ratio aptamer sensor based on the electrochemistry and photoelectrochemistry dual methods is put forward for the first time for specific detection of the streptomycin. According to the preparation method and application of the ratio sensor, in the presence of the streptomycin, a methylene blue labeled streptomycin aptamer (abbreviated as MB-Apt) can be specifically combined with the streptomycin, and the MB-Apt conformation is changed, so that the MB-Apt is disengaged from the surface of an electrode, and double changes of a photoelectric chemical signal and an electrochemical signal are further caused. The linear response range of the constructed sensor to the streptomycin is 3.0*10<-8> mol/L to 1.0*10<-4> mol/L, and the detection limit is 1.0*10<-8> mol/L. The ratio aptamer sensor based on the electrochemistry and photoelectrochemistry dual methods has good selectivity and high sensitivity, higher accuracy is obtained by combining the two methods, and a novel sensing platform is provided for measuring the streptomycin in an actual sample.

Through one-off screen-printing, working electrode is prepared by printing commercial carbon ink on plastic film. Printing Ag/AgCl ink produces a counter electrode and a reference electrode. Then, analysis fluid of alcohol dehydrogenase is dropped to a reaction cavity between the working electrode and the reference electrode. After natural seasoning electrode piece, using double face adhesive tape sticks the transparent glue onto the electrode piece so as to form a small electrolytic cell between the transparent glue and the plastic film. When enzyme electrode immerges to blood sample to be tested, reaction is taken place between the enzyme electrode and the sample. Under action of electric field, electron transfer occurs to for current. Based on coincidence relation between electric chemical signal and concentration of substrate to be measured, alcohol concentration in blood can be measured. Features are: high sensitivity, accuracy, low cost, one-off use, and batch production.

The invention discloses a preparation method of a microelectrochemical sensor for detection of dopamine concentration in an animal brain, wherein a silicon-based microelectrode array is used as an electrode to be modified; firstly, an electrodeposition method and a chemical etching method are used to deposit a layer of porous gold-platinum nanoparticles on the electrode sites of the silicon-basedmicroelectrode array, then an electropolymerization is used to deposit a layer of perfluorosulfonic acid (Nafion) film on the electrode sites modified with the gold-platinum nanoparticles to obtain the microelectrochemical sensor for detection of dopamine concentration. The prepared microelectrochemical sensor for detection of dopamine concentration in the animal brain is implanted into striatum nuclei of the animal brain, and is connected as a working electrode to an electrochemical workstation to realize detection of dopamine concentration in the animal brain by detecting of a dopamine electrochemical signal, and the microelectrochemical sensor is simple in preparation, high in sensitivity, strong in selectivity, and small in volume.

The invention discloses an electrochemical sensor based on DNA configuration transformation.The electrochemical sensor comprises an electrode and a capturing probe DNA.The capturing probe DNA is of a nuchal-ring single-chain structure, the 3' end of a DNA chain is used for modifying methylene blue, the 5' end of the DNA chain is used for modifying sulfydryl, and the capturing probe DNA stands on the surface of the electrode under the interaction between the sulfydryl and the electrode.According to the electrochemical sensor, the electrochemical indicator methylene blue (MB) is modified to the nuchal-ring DNA probe; after target DNA and ATP are reacted with the probe DNA, the configuration of the probe DNA is changed, an electrochemical signal is changed, and the target DNA and the ATP are detected at the same time without replacing the sensor.In other words, two components are detected with one nuchal-ring DNA, and the complexity of an experiment is lowered.On the basis, it can be further expanded that selective or simultaneous detection or any two or more target molecules is achieved with one DNA probe.

The invention relates to a single-molecule analysis method for detecting methylated DNA. According to the method, in an electrolytic tank containing a tetramethyl ammonium salt electrolyte or a tetraethyl ammonium salt electrolyte or a tetrapropyl ammonium salt electrolyte or a tetrabutyl ammonium salt electrolyte, a nanopore sensor distinguishes and detects DNA of different methylation levels through current electrochemical signals, wherein DNA of different methylation levels includes un-methylated DNA, mono-methylated DNA and multi-methylated DNA, and the structural forms of DNA include a single-stranded structural form, a double-stranded structural form and a hairpin structural form. According to the single-molecule analysis method for detecting methylated DNA, the quantity of needed samples is small, sensitivity is high, and single-base resolution is achieved; nanopore and DNA modification, DNA amplification and marking are not needed, operation is easy, and high applicability is achieved.

The invention provides a mechanical and biologic experimental apparatus to provide mechanical and chemical signals synchronously, and is characterized in that a two-layer fluid chamber, which is a core part, consists of an upper layer, a middle layer and a lower layer, which are combined. The two-layer fluid chamber comprises an upper-layer chamber and a lower-layer chamber. Each of the chambers is provided with an inlet and an outlet. The heads of the inlet and the outlet of the upper layer chamber are T-shaped, and are used to develop entry flow. A lower liquid storage tank is connected with an upper liquid storage tank through a peristaltic pump. An overflow pipe arranged inside the upper liquid storage tank is connected with the lower liquid storage tank so that superfluous liquid directly flows into the lower liquid storage tank through the overflow pipe orifice to keep the liquid level inside the upper liquid storage tank constant. The outlet of the upper liquid storage tank is connected with the inlet of the upper layer chamber. The outlet of the upper layer chamber is connected with the lower liquid storage tank. The inlet and the outlet of the lower layer chamber are connected with a replenishment liquid storage tank to keep the concentration of the liquid inside the lower-layer chamber constant, and to keep the liquid in the lower layer chamber still relative to the fluid inside the upper layer chamber. The two-layer fluid chamber and the upper liquid storage tank are arranged on the upper mounting plate of a metal holder; the replenishment liquid storage tank is arranged on the middle mounting plate of the metal holder; the lower liquid storage tank is arranged on the lower mounting plate of the metal frame. The two-layer fluid chamber, the upper liquid storage tank, the replenishment liquid storage tank and the lower liquid storage tank are connected through pipes and constitute a whole.

A method of photochemically amplifying the chemical signal associated with unmasking a photosensitizer and releasing a radical leaving group when a photochemical chain reaction is initiated by a sensitizer attached to a molecule of interest is provided. More specifically, provided is a method of photoinduced amplification comprising: providing a plurality of masked photosensitizers, each masked photosensitizer having a masking group bonded to a photosensitizer through a releasable covalent bond which disrupts the conjugation of the photosensitizer; providing a reaction photosensitizer in releasing proximity to a first masked photosensitizer; exciting the reaction photosensitizer with photoradiation, whereby the reaction photosensitizer induces release of the masking group from the first masked photosensitizer, producing a first unmasked photosensitizer which induces release of the masking group from a second masked photosensitizer in releasing proximity to the first masked photosensitizer, and so on. The release of the masking group from masked photosensitizer continues as long as masked photosensitizers are in releasing proximity to the reaction photosensitizer, or until a side reaction occurs which stops the chain propagation, or until the source of light is turned off.

The invention discloses an ionic liquid functional graphene vibrio DNA electrochemical sensor and a preparation method and application thereof. Firstly, ZIF-8 is prepared in graphene oxide dispersion;then a graphene-ZIF-8 compound is subjected to covalent modification by amino functional ionic liquid to prepare an ionic liquid functional graphene-ZIF-8 compound; a gold electrode modified by the compound is prepared by a dispensing method; and then vibrio probe ssDNA is fixed on the surface of the modified electrode by a biological linker so as to prepare the vibrio DNA sensor. The DNA sensorhas excellent sensitivity and selectivity, a low detection limit and a wide linear range. The preparation method comprises: preparation of an electrode modification material; preparation of an electrochemical vibrio parahaemolyticus DNA sensor; hybridization of the electrochemical vibrio parahaemolyticus DNA sensor and target DNA; and sensor electrochemical signal detection. The sensor is simple in operation method and has potential application value.

The invention discloses a clamp for acoustic emission testing of the material corrosion property and a using method thereof. The device is composed of a stepped thread waveguide rod, a primary sleeve, a secondary sleeve, a tertiary sleeve, a sealing ring and an acoustic emission sensor. A first external thread of the stepped thread waveguide rod is connected with an internal thread of the primary sleeve, a second external thread of the stepped thread waveguide rod is arranged on the outer side of a second cavity of the primary sleeve, a fixing end is arranged at the rear end of the stepped thread waveguide rod, and the acoustic emission sensor is arranged at the fixing end; an external thread of the primary sleeve is connected with an internal thread of the tertiary sleeve, so that the primary sleeve is arranged inside a third cavity and a fourth cavity of the tertiary sleeve; the tertiary sleeve is sleeved with the secondary sleeve, and the sealing ring is arranged between the tertiary sleeve and the secondary sleeve. A sample is installed in a thread-connection mode, corrosion acoustic emission and electric chemical signals are transmitted through the stepped thread waveguide rod, and compared with a traditional mode, the sample is more portable and more efficient to assemble, disassemble and clean.

The invention discloses a preparation method of an electrochemical biosensor for simultaneously detecting Exo I and TdT. Sulfhydryl DNA and a gold electrode surface form an Au-S covalent bond spontaneously by a mercapto part and the sulfhydryl DNA is fixed on the gold electrode surface. Polymerization of the 3'-OH tail of the TdT catalytic sulfydryl DNA and dCTP is carried out and a generated rich-C DNA long chain can used for forming AgNCs; and the TdT activity is detected by a dissolved voltammetric signal of Ag. Before TdT polymerization, Exo I is introduced and the sulfhydryl DNA can be hydrolyzed, so that the formation of AgNCs is affected finally; and thus the ExoI activity is detected. The electrochemical signal intensity can be affected by changing the ExoI or TdT concentration; and on the basis of the principle, a high-efficiency electrochemical biosensor for simultaneously detecting Exo I and TdT is prepared.

The invention provides an intelligent detection system for body parameters, which includes a detection bracelet and a client connected to the detection bracelet; a detection device is provided on the detection bracelet, and the detection device includes a processor and a device electrically connected to the processor. Sensor, wireless communication module, display module; the sensor is an electrochemical biosensor, and the electrochemical biosensor includes an electrode, a signal conditioning circuit, a microprocessor, and an A/D converter; the electrode converts the detected chemical signal into a current signal, and the current The signal is converted into a voltage by a signal conditioning circuit, and the voltage is converted into a corresponding digital quantity by an A/D converter, and the microcontroller transmits the digital quantity signal to the client. The present invention uses an electrochemical biosensor to measure the lactic acid content in sweat in real time, and reminds workers to take a rest in real time to avoid physical injury caused by excessive physical exertion. The present invention has simple equipment, low cost, strong practicability, and high degree of intelligence.