As a kind of mode that can be realized, in step S203, during the periodical movement process of the outlet end 112 of the spit gun head 110 under the second liquid level, the velocity of the outlet end 112 of the spit gun head 110 is Changes in a rectangular wave. The velocity of the outlet end 112 of the spout tip 110 changes in a rectangular wave, and enters a constant velocity phase after the acceleration phase ends, which is beneficial for the motion control mechanism 130 to accurately control the motion state of the outlet end 112 of the spit tip 110 . Optionally, the high time and low time of the rectangular wave representing the change in the velocity of the outlet port 112 of the spout tip 110 may be equal or different. Further, in step S203 , during the periodical movement of the outlet end 112 of the spit gun head 110 below the liquid level of the second liquid, the velocity of the outlet end 112 of the spit gun head 110 changes in a square wave. The high time and low time of the rectangular wave representing the change in the velocity of the outlet port 112 of the spout gun head 110 are equal. When the rectangular wave representing the change in velocity of the outlet end 112 of the liquid spout tip 110 is at a low position, the velocity of the outlet end 112 of the liquid spit gun tip 110 is zero or has a velocity in the opposite direction relative to the high position. As shown in Figure 4, further, in the first half period and the second half period of the periodic movement of the outlet end 112 of the spit gun head 110, the velocity of the outlet end 112 of the spit gun head 110 is the same in magnitude and opposite in direction . One movement cycle of the outlet end 112 of the spout tip 110 includes two instantaneous acceleration movements in opposite directions.
As shown in Fig. 8 and Fig. 9, the spit gun head 110 that an embodiment of the present invention provides also comprises needle pin 114, and pin pin 114 has the liquid reservoir 115 that runs through pin pin 114 along the extending direction of pin pin 114 . One end of the liquid storage tank 115 communicates with the end of the needle stem 113 away from the outlet end 112 of the spout gun head 110 , and the end of the needle plug 114 away from the needle stem 113 is the inlet end 111 of the spout gun head 110 . The pintle 114 is fixedly connected with the needle barrel 113 . The first liquid used to generate micro-droplets 199 can be stored in the pintle 114 in advance, which can realize continuous and batch generation of micro-droplets 199 . Further, a locking groove 116 is formed on the inner surface of the end of the pintle 114 away from the needle barrel 113 . The card slot 116 can realize the detachable connection with the fluid driving mechanism 120 . It is convenient to replace the liquid spit gun head 110 .
Described digital PCR detector 1 integrates described droplet generation device 10, described temperature control device 20, described fluorescent signal detection device 30 and described quantitative analysis device 40, makes described operator can The realization of automatic operation not only improves the work efficiency, but also has the advantages of fast response, good repeatability, high sensitivity, strong specificity and clear results.
Described first liquid and second liquid also can be two kinds of liquids with interfacial reaction, and in one embodiment of the invention, described first liquid is sodium alginate aqueous solution, and described second liquid is oxidation An aqueous calcium solution, such as a calcium oxide aqueous solution with a mass concentration of 1%, has an interfacial reaction between the two, and the generated droplets are calcium alginate gel microspheres. The present application can also form a plurality of droplets of different components and volumes in the open container in sequence by replacing the spout tip or the component of the first liquid flowing out of the spit tip, which can be used to realize large-scale Micro-volume high-throughput screening can also realize multi-step ultra-micro biochemical reactions and detection, and has broad application prospects.
Described temperature control device 20 carries out nucleic acid amplification reaction to described a plurality of micro-droplets, and gathers the product signal of described a plurality of micro-droplets after nucleic acid amplification reaction by described fluorescent signal detection device 30, Such as fluorescence, ultraviolet absorption, turbidity and other signals. The difference in composition between the multiple amplified and non-amplified micro-droplets is used to analyze the number of amplified droplets of the target sequence, and finally realize the quantitative analysis of nucleic acid molecules. By monitoring the fluorescence change pictures of the multiple micro-droplets in real time, the detection result is direct, and the problems of false positives and false negatives in the multiple micro-droplets can be solved.
In one embodiment of the present invention, the power assembly 122 pushes the push rod 1212 to slide at a constant speed in the syringe 1211, which means that the driving liquid 1214 is driven by the push rod 1212 at a uniform flow rate from the liquid in and out of the variable volume assembly 121 Exhaust from port 1213 enters the dispensing tip 110 through the thin tube 123 at a uniform flow rate. Driven by the driving liquid 1214 , the first liquid 190 stored in the nozzle head 110 is discharged out of the outlet port 112 of the nozzle head 110 at a uniform flow rate. By using the driving liquid 1214 as the transmission medium and controlling the push rod 1212 to discharge the driving liquid 1214 at a uniform flow rate, the fluid driving mechanism 120 provided in this embodiment can not only discharge the first The liquid 190 is discharged from the outlet port 112 of the dispensing gun tip 110 . Even if the liquid discharge gun head 110 is in a state of rapid vibration, the fluid driving mechanism 120 provided in this embodiment can still ensure that the first liquid 190 is discharged from the outlet end 112 of the liquid discharge gun head 110 at a uniform flow rate. The fluid driving mechanism 120 provided in this embodiment greatly improves the volume and size uniformity of the generated micro-droplets 199 .
In the above-mentioned micro-droplet generation method, because the acceleration value is larger when the outlet end 112 of the described spit gun head 110 is ac...
