Brain natriuretic peptide aptamer fluorescence detection device based on smart phone and sensing method of same

A BNP aptamer fluorescence detection device based on a smart phone, comprising a detection control mechanism, a fluorescence rapid detection mechanism and an aptamer fluorescence sensor;

• wherein the detection control mechanism includes a power supply module, a microcontroller, an excitation light source, a signal acquisition and photoelectric conversion module, a signal chain processing module and a Bluetooth module, the input end of the power supply module is configured to connect with the USB interface of a smart phone, which outputs a power supply voltage to the power supply module, and supplies power to the the detection control mechanism;
• the microcontroller is connected with the excitation light source, the signal acquisition and photoelectric conversion module and the signal chain processing module by way of signals, and can be connected to the smart phone by way of signals through the Bluetooth module;
• the excitation light source is configured to turn on and off according to the control signal of the microcontroller, and generate excitation light with a set wavelength;
• the signal acquisition and photoelectric conversion module is configured to capture a fluorescence signal generated form the solution to be detected according to the control signal of the microcontroller, and convert the fluorescence signal into an electrical signal, which is transmitted to the microcontroller;
• the signal chain processing module is configured to receive electrical signals transmitted by the microcontroller, perform analog-to-digital conversion and filter amplification on the electrical signal, and transmit processed results to the microcontroller;
• the Bluetooth module is configured to transmit a command signal of a smart phone to the microcontroller, and transmit processed results obtained by the microcontroller to a smart phone to display;
• the fluorescence rapid detection mechanism is configured to place the aptamer fluorescence sensor to detect BNP under the control of the detection control mechanism;
• the fluorescence rapid detection mechanism includes a main box and a smart phone support, the smart phone support is configured to place a smart phone to carry out power supply, detection operation and result display by means of the smart phone;
• the inside of the main box is provided with an inner shell, which is distanced from the main box to a certain extent;
• the signal acquisition and photoelectric conversion module and a main control circuit board are fixed and installed on the inner shell, which is provided with a fixing hole of excitation light sources;
• the main control board integrates the power supply module, the microcontroller, the signal chain processing module and the Bluetooth module;
• a fluorescent signal reaction table is arranged inside the inner shell, the portion of the fluorescence signal reaction table far away from the fixing hole of excitation light sources is provided with a fluorescence signal reaction cell, which is used to place a quartz cuvette containing the solution to be detected;
• the portion of the fluorescence signal reaction table close to the fixing hole of excitation light sources is provided with a thread fixing hole for excitation light, which communicates with the fluorescence signal reaction cell, and is coaxial with the fixing hole of excitation light sources, so that the fixing hole of excitation light sources and the thread fixing hole for excitation light jointly fix a LED excitation light source;
• the connection of the thread fixing hole for excitation light and the fluorescence signal reaction cell is provided with an excitation filter groove, which is used to accommodate an excitation filter;
• a connection body is set between the fluorescence signal reaction table and the inner shell, and an emitted-light receiving hole is opened inside the connection body;
• the emitted-light receiving hole communicates with the fluorescence signal reaction cell, and the emitted-light receiving hole and the thread fixing hole for excitation light are vertical with each other in the horizontal direction at the fluorescence signal reaction cell;
• the connection between the emitted-light receiving hole and the fluorescence signal reaction cell is provided with an emission filter slot, which is used to accommodate a emission filter;
• thus, the excitation light with a preset wavelength generated from the excitation light source irradiates the fluorescence signal reaction cell via the excitation filter, and the solution to be detected in the quartz cuvette inside the fluorescence signal reaction cell generates a fluorescent signal, which is transmitted to the signal acquisition and photoelectric conversion module through the emitted-light receiving hole after passing through the emission filter;
• the aptamer fluorescence sensor is prepared by using oligonucleotides marked by carboxy fluorescein as an aptamer and carboxylated graphene oxide as a fluorescence quencher for the BNP detection, so as to obtain the signal response relation between the BNP concentration and fluorescence intensity according to the analysis of multi-groups of experimental data.