4results about How to "High sensitivity detection" patented technology

This application discloses an embedded whole-cell biosensor, its fabrication method, and its application in machine learning-assisted mercury ion detection, belonging to the field of sensor materials and detection technology. This sensor encapsulates *E. coli* expressing green fluorescent protein (GFP) in a polyacrylamide / hyaluronic acid (PAAM / HA) hydrogel matrix, enabling highly selective and sensitive detection of mercury ions. It effectively eliminates interference from competing metal ions and can be completely regenerated through EDTA-2Na treatment, allowing for repeated use without performance loss. It maintains a stable fluorescence response for up to three weeks, possesses excellent biocompatibility and biodegradability, minimizing the risk of secondary contamination, and facilitates rapid on-site analysis.

This invention provides a rapid colorimetric reagent for the detection of manganese and iron ions. The reagent consists of carbon dots, a 3,3′,5,5′-tetramethylbenzidine solution, and a phosphate buffer solution. The reagent itself is a brown, transparent solution. When manganese ions are added to the 3,3′,5,5′-tetramethylbenzidine solution and phosphate buffer solution, it turns blue (visible to the naked eye) upon irradiation with a 365 nm UV lamp; upon contact with iron ions in the 3,3′,5,5′-tetramethylbenzidine solution, it turns dark green (visible to the naked eye). This reagent exhibits an extremely low detection limit and good selectivity. The detection process does not require complex analytical equipment, enabling rapid trace detection of manganese and iron ions. The reagent is simple to prepare, overcoming the shortcomings of cumbersome and expensive synthesis of manganese and iron ion detection probe molecules, and providing effective technical support for trace detection in food safety.

The application discloses a long-afterglow nano carrier and a preparation method and application thereof, and belongs to the field of biomedical materials. The long-afterglow nano carrier comprises a near-infrared luminescent center, an organic mesoporous silica layer and an autophagy inhibitor; the organic mesoporous silica layer is coated on the outer layer of the near-infrared luminescent center, and the autophagy inhibitor is loaded in the mesopores of the organic mesoporous silica layer; the near-infrared luminescent center comprises a transition metal element; the organic mesoporous silica layer is prepared by co-condensation of an organic silane precursor and an inorganic silicon precursor, wherein the organic silane precursor is an organic silane containing a tetrasulfide bond, and the inorganic silicon precursor is a silicate compound. The carrier can specifically respond to excessively high concentration of hydrogen peroxide in a tumor microenvironment, and accurately release the loaded autophagy inhibitor; the release process can be observed by positioning with the aid of a high signal-to-noise ratio afterglow signal, thereby providing guidance for subsequent drug release, and finally realizing efficient radiotherapy sensitization.

The application provides a biosensor based on a screen-printed electrode and a preparation method and application thereof. The preparation method comprises the following steps: a, depositing a silicon thin film transition layer on the surface of a working electrode of a screen-printed electrode by using a PECVD device; b, spin-coating a tin dioxide solution on the surface of the silicon thin film transition layer to form a tin dioxide layer; c, first performing hydrogen reduction on the surface of the tin dioxide layer, and then performing silicon nanowire growth to obtain a silicon nanowire layer; d, first performing ultraviolet ozone treatment on the silicon nanowire layer, then placing the silicon nanowire layer in an alcohol solution containing 3-aminopropyl triethoxysilane to perform condensation reaction, cleaning, then performing heating to enhance the coupling strength, and finally placing the silicon nanowire layer in a phosphate buffer solution containing a nucleic acid aptamer to fix the nucleic acid aptamer, so as to obtain the biosensor. The application prepares silicon nanowires on a screen-printed electrode, then fixes a nucleic acid aptamer, and constructs an electrochemical sensor for detecting Alzheimer's disease, and the electrochemical sensor has excellent conductivity, biocompatibility and detection sensitivity.