CN106442276A - Device and method for judging whether biological cells are captured successfully in optical stretcher - Google Patents

Abstract

The invention relates to a device and method for judging the successful capture of biological cells in an optical stretcher, and belongs to the fields of optical engineering and precision measurement technology. The device is composed of No. 1 optical beam splitter, No. 2 optical beam splitter, No. 1 photodetector and No. 2 photodetector. The No. 1 optical beam splitter and No. 2 optical beam splitter are respectively located in two On the optical path of the incident laser light, No. 1 photodetector is connected with No. 1 optical beam splitter, and No. 2 photodetector is connected with No. 2 optical beam splitter. The present invention judges in real time whether the biological cells have been successfully captured by measuring the return light power, and is applied to the optical stretcher under the condition of no imaging system, and utilizes the components of the dual-beam light trap system itself in the optical stretcher to the greatest extent, The detection can be completed only by connecting an optical beam splitter and a photodetector, and has the advantages of simple structure, high sensitivity, and strong practicability. In addition, the present invention is not limited to biological cell types and chip structures, and has a very wide application range.

Description

A device and method for judging the successful capture of biological cells in an optical stretcher

technical field

The invention relates to a device and method for judging the successful capture of biological cells in an optical stretcher, and belongs to the fields of optical engineering and precision measurement technology.

Background technique

The characterization of mechanical and mechanical properties at the single-cell level can effectively clarify the function of cells and explain the differences in cell monomers, which is of great significance for cell differentiation and pathological research, as well as early clinical diagnosis and treatment of diseases. Optical stretchers are tools for studying the mechanomechanical properties of individual biological cells. It is essentially a dual-beam optical trap capable of confining micron-scale particles formed by two Gaussian laser beams with the same power and aligned directions propagating toward each other. After the biological cells are successfully captured by the dual-beam optical trap, the cells can be stretched and deformed by changing the power of the captured laser, so as to achieve the purpose of studying the mechanical properties of biological cells. The optical stretcher captures and stretches without mechanical contact, does not need to focus the laser, and can minimize cell damage, so its application prospects are very broad.

In the process of using the optical stretcher, the measurement of cell stretching and mechanical properties can only be carried out after the biological cells are successfully captured, so it is necessary to judge whether the biological cells are successfully captured. At present, the judgment of biological cell capture in the optical stretcher mainly relies on the combination of microscopic imaging and manual judgment. Use a CCD or CMOS digital camera to continuously collect plane images of the light trap to judge the state of the biological cells. When the biological cells are in the light trap and keep still, the biological cells are considered to be successfully captured by the dual-beam light trap. This method has three disadvantages: one is that it is limited by the sampling frequency of the camera, and the image transmission has a delay and the accuracy is not high; the other is that the camera is bulky, which is not conducive to system integration; the third is that the camera is expensive. A device and method for judging the capture of biological cells in an optical stretcher by using optical power measurement, especially for a device and method for accurately judging whether biological cells in a double-beam optical trap have been successfully captured under the condition that an imaging system cannot be installed, There is no report yet.

Contents of the invention

In order to overcome the deficiencies of the prior art, the present invention proposes a device and method for judging whether the biological cells in the optical stretcher have been successfully captured by measuring the power of the returned light.

The invention is based on the following principle: two Gaussian laser beams with the same power and aligned directions propagating in opposite directions form a double-beam optical trap capable of confining micron-scale particles. These two Gaussian laser beams are called trapping lasers. The first capture laser beam will propagate to the side of the second capture laser beam after passing through the biological cells, and at the same time, part of the second capture laser beam will propagate to the side of the second capture laser beam in the opposite direction after being scattered by the biological cells. The two parts of laser light are collectively referred to as the return light, and there is also return light on the side of the first captured laser beam. Keeping the laser power constant, when there are no biological cells in the double-beam optical trap, the return light power is in a stable state; when the biological cells enter the optical trap, due to the occlusion of the biological cells, the return light power fluctuates violently; when the biological cells are successfully captured When , the value of the return light power decreases, and the fluctuation range is significantly lower than that when it is not captured.

The technical scheme adopted in the present invention is as follows: a device for judging the successful capture of biological cells in an optical stretcher, consisting of No. 1 optical beam splitter, No. 2 optical beam splitter, No. 1 photodetector and No. 2 photodetector , the No. 1 optical beam splitter and the No. 2 optical beam splitter are respectively located on the optical path of the two incident laser beams, the No. 1 photodetector is connected with the No. 1 optical beam splitter, and the No. 2 photodetector is connected with the No. 2 optical splitter. The No. 1 optical beam splitter splits the incident laser light into two beams, one beam is used as the first captured laser beam, and the other beam enters the No. 1 photodetector connected to the No. 1 optical beam splitter, and the No. 1 photoelectric detector The detector is used to read the optical power output by the No. 1 optical beam splitter, and then monitor the incident optical power W; the No. 2 photodetector is connected to the No. The return light power W1 is monitored in real time by the No. 2 photodetector to determine whether the biological cells are successfully captured. The incident light power W is monitored in real time by the No. 1 photodetector to confirm that the incident light power is stable, thereby eliminating the impact of the incident light power on the return light. The effect of optical power.

The beneficial effects of the present invention are:

The present invention judges in real time whether the biological cells have been successfully captured by measuring the back light power, and is applied to the optical stretcher under the condition of no imaging system, and utilizes the components of the dual-beam light trap system itself in the optical stretcher to the greatest extent, The detection can be completed only by connecting an optical beam splitter and a photodetector, and has the advantages of simple structure, high sensitivity, and strong practicability. In addition, the present invention is not limited to biological cell types and chip structures, and has a very wide application range.

Description of drawings

Fig. 1 is the structural representation of device of the present invention;

Fig. 2 is the embodiment schematic diagram of device of the present invention;

Fig. 3 is a schematic diagram of the change of the back light power before and after the biological cells are captured.

In the figure, 1 is the biological cell, 2 is the first captured laser beam, 3 is the second captured laser beam, 4 is the transmitted light of the first captured laser beam, 5 is the scattered light of the second captured laser beam, and 6 is the first light beam Beam splitter, 7 is the No. 2 optical beam splitter, 8 is the No. 1 optical power meter, 9 is the No. 2 optical power meter, 10 is the cell chamber, 11 is the No. 1 laser, 12 is the No. 2 laser, 13 is the No. 1 laser Optical isolator, 14 is No. 2 optical isolator.

detailed description

An embodiment of the present invention will be described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention should not be limited thereby.

As shown in Figure 1, a device for judging the successful capture of biological cells in an optical stretcher consists of No. 1 optical beam splitter 6, No. 2 optical beam splitter 7, No. 1 photodetector 8 and No. 2 photodetector 9 components, the No. 1 optical beam splitter 6 and the No. 2 optical beam splitter 7 are respectively located on the optical path of the two incident laser beams, the No. 1 photodetector 8 is connected with the No. 1 optical beam splitter 6, and the No. 2 photodetector The device 9 is connected with the No. 2 optical beam splitter 7; the No. 1 optical beam splitter 6 divides the incident laser light into two beams, one beam of light is used as the first beam capture laser 2, and the other beam of light is incident with the No. 1 optical beam splitter 6 Connected No. 1 photodetector 8, No. 1 photodetector 8 is used to read the optical power output by No. 1 optical beam splitter 6, and then monitors the incident optical power W; No. 2 photodetector 9 and No. 2 optical beam splitter 7 is connected to monitor the return light power W1 coupled by the No. 2 optical beam splitter 7. The return light power W1 is monitored in real time through the No. 2 photodetector 9 to determine whether the biological cells are successfully captured. The No. 1 photodetector 8 The incident light power W is monitored in real time to confirm that the incident light power is stable, so as to exclude the influence of the incident light power on the return light power.

The embodiment of the present invention is shown in Fig. 2, the light source of two incident lasers selects two lasers: laser No. 11 and No. Room 10. The output powers of the No. 1 laser 11 and the No. 2 laser 12 are set to be equal to ensure that the powers of the first capture laser 2 and the second capture laser 3 incident on the cell chamber 10 are equal. No. 1 laser 11 is connected to No. 1 optical isolator 13, and No. 2 laser 12 is connected to No. 2 optical isolator 14, both of which are used to isolate reflected light and protect the lasers. Auxiliary tools such as a three-dimensional translation stage are used to ensure that the two laser beams are completely aligned and then incident on the cell chamber 10 to achieve the purpose of capturing the biological cells 1 in the cell chamber 10 .

As shown in Figure 2, No. 1 optical beam splitter 6 and No. 2 optical beam splitter 7 are located on the optical path of the two incident laser beams respectively, No. 1 photodetector 8 is connected with No. 1 optical beam splitter 6, No. 2 photoelectric detector The detector 9 is connected with the No. 2 optical beam splitter 7; the No. 1 optical beam splitter 6 divides the incident laser light into two beams, one beam of light is used as the first beam to capture the laser light 2, and the other beam of light is incident to the No. 1 optical beam splitter No. 1 photodetector 8 connected with 6, No. 1 photodetector 8 is used to read the optical power output by No. 1 optical beam splitter 6, and then monitor the incident light power W; No. 2 photodetector 9 and No. 2 optical splitter Beamer 7 is connected to monitor the return light power W1 coupled by No. 2 optical beam splitter 7. Real-time monitor the return light power W1 through No. 8. Monitor the incident light power W in real time to confirm that the incident light power is stable, thereby eliminating the influence of the incident light power on the return light power.

Concrete work process of the present invention is as follows:

Turn on the No. 1 laser 11 and the No. 2 laser 12, and set the output power of the two to an equal value. The two beams of laser light emitted by the No. 1 laser 11 and the No. 2 laser 12 pass through the No. 1 beam splitter 6 and the No. 2 beam respectively. The beam splitter 7 irradiates the cell chamber 10 to form a double-beam optical trap. At this time, the No. 1 photodetector 8 connected to the No. 1 optical beam splitter 6 measures the incident light power of the outgoing beam of the No. 1 optical beam splitter 6. W, the return light power W1 measured by the No. 2 photodetector 9 connected to the No. 2 optical beam splitter 7 , and the return light power is stable at this time, as shown in the time period of "no biological cells" in FIG. 3 .

Inject biological cells 1 into the cell chamber 10. When biological cells enter the optical trap, due to the existence of biological cells, the intensity of transmitted light and scattered light changes, and the return light power W1 fluctuates violently, as shown in "Biological cells entering the light trap" in Figure 3. Trapped but not captured" time period; when the biological cells were successfully captured by the double-beam optical trap, the value of the return light power W1 decreased, and the fluctuation range was significantly lower than that when it was not captured, as shown in Figure 3 "Biological cells were successfully captured "period.

During the whole process, the reading of No. 1 photodetector 8 remains unchanged, and by monitoring the reading of No. 2 photodetector 9, it can be judged whether the biological cells are successfully captured in the optical stretcher.

Claims (3)

1. A device for judging the successful capture of biological cells in an optical stretcher, characterized in that: the device consists of a No. 1 optical beam splitter (6), a No. 2 optical beam splitter (7), a No. 1 photodetector (8) and No. 2 photodetectors (9), the No. 1 optical beam splitter (6) and the No. 2 optical beam splitter (7) are respectively located on the optical paths of the two beams of incident laser light, and the No. 1 photoelectric detector The device (8) is connected to the No. 1 optical beam splitter (6), and the No. 2 photodetector (9) is connected to the No. 2 optical beam splitter (7); the No. 1 optical beam splitter (6) splits the incident laser light into two One beam of light is used as the first beam of captured laser light, and the other beam of light is incident on the No. 1 photodetector (8) connected to the No. 1 optical beam splitter (6), and the No. 1 photodetector (8) is used to read The optical power output by the No. 1 optical beam splitter (6), and then monitor the incident optical power W; the No. 2 photodetector (9) is connected with the No. 2 optical beam splitter (7) for monitoring the No. 2 optical beam splitter (7) The returned optical power W1 that is formed by coupling is monitored in real time by the second photodetector (9) to determine whether the biological cell is successfully captured, and the incident optical power W is monitored in real time by the first photodetector (8). Confirm that the incident light power is stable, so as to exclude the influence of the incident light power on the return light power. 2. according to claim 1, the described device for judging the successful capture of biological cells in the optical stretcher is characterized in that: the light sources of the two incident lasers select two lasers, No. 1 laser (11) and No. 2 laser (12) ), two beams of lasers emitted from the No. 1 laser (11) and the No. 2 laser (12), oppositely transmit the input cell chamber (10), and the output power settings of the No. 1 laser (11) and the No. 2 laser (12) be equal values, to ensure that the power of the first capture laser and the second capture laser of the incident cell chamber (10) are equal, the No. 1 laser (11) is connected with the No. 1 optical isolator (13), and the No. 2 laser (12 ) is connected with the No. 2 optical isolator (14), both are used to isolate reflected light and protect the laser. 3. according to the method for judging the successful capture of biological cells in the optical stretcher by the device according to claim 1 or 2, it is characterized in that the method comprises the following steps: open No. 1 laser (11) and No. 2 laser (12), turn on The output power of the two is set to the same value, and the two laser beams emitted by the No. 1 laser (11) and the No. 2 laser (12) pass through the No. 1 optical beam splitter (6) and the No. 2 optical beam splitter (7) respectively. After irradiating to the cell chamber (10), a double-beam optical trap is formed. At this time, the No. 1 photodetector (8) connected to the No. 1 optical beam splitter (6) measures the output beam of the No. 1 optical beam splitter (6). The incident light power W of No. 2 photodetector (9) that links to each other with No. 2 optical beam splitter (7) measures return light power W1, and this moment return light power is stable; Inject biological cells into the cell chamber (10), when the biological cells enter the optical trap, due to the existence of biological cells, the intensity of transmitted light and scattered light changes, and the return light power W1 fluctuates violently; when the biological cells are successfully captured by the double-beam optical trap When captured, the return light power W1 value decreases, and the fluctuation range is significantly lower than that when not captured; During the whole process, the reading of the No. 1 photodetector (8) remains unchanged, and by monitoring the reading of the No. 2 photodetector (9), it is judged whether the biological cells are successfully captured in the optical stretcher.