CN113604357A

CN113604357A - Three-dimensional force cell loading device and pneumatic control method

Info

Publication number: CN113604357A
Application number: CN202110865219.8A
Authority: CN
Inventors: 徐振邦; 周成波; 夏明一
Original assignee: Changchun Institute of Optics Fine Mechanics and Physics of CAS
Current assignee: Changchun Institute of Optics Fine Mechanics and Physics of CAS
Priority date: 2021-07-29
Filing date: 2021-07-29
Publication date: 2021-11-05

Abstract

The invention provides a loading device of three-dimensional force cells, which comprises: the transparent cover, the culture plate, the loading plate and the loading base are sequentially arranged from top to bottom; the culture plate comprises an outer frame and at least one cell culture hole, and the cell culture hole is fixedly connected inside the outer frame; the cell culture hole bears cells through a loading membrane, and is isolated from the external environment through a transparent cover; the loading base is a cavity structure with an opening at the top; the outer frame is hermetically connected with the loading base; the loading plate is provided with loading platforms corresponding to the number of the loading membranes, and the loading membranes are positioned above the loading platforms; the loading platform is provided with a groove and an air hole, and the groove is connected with the loading air chamber through the air hole. The device can realize mechanical loading in a three-dimensional space and has a simple structure.

Description

Three-dimensional force cell loading device and pneumatic control method

Technical Field

The invention relates to the field of cell mechanics, in particular to a loading device and a pneumatic control method for three-dimensional force cells.

Background

At present, in vitro cell culture provides an ideal research method for researching the influence of various physical and biochemical factors on human tissues. The loading mode of the cells in vitro mainly comprises the following steps: a fluid shear stress loading method, a pressure loading mode and a strain loading mode. The loading mode has the defects of complex device structure, uneven stress and the like, most devices provide loading force in a plane, and multiple groups of experiments cannot be carried out simultaneously.

Therefore, based on these problems, a loading device for three-dimensional force cells is needed to solve the above problems.

Disclosure of Invention

The invention provides a loading device for three-dimensional force cells to solve the problems.

In order to realize more uniform stress of cells and simplify the structural complexity of the device, the invention adopts the following specific technical scheme:

a loading device for three-dimensional force cells comprises a transparent cover, a culture plate, a loading plate and a loading base which are sequentially arranged;

the culture plate comprises an outer frame and at least one cell culture hole, and the cell culture hole is fixedly connected inside the outer frame;

the cell culture well comprises a loading membrane arranged at the bottom of the well, the loading membrane is used for loading cells, and the cell culture well is isolated from the external environment through the transparent cover;

the loading base is a cavity with an opening at the top;

the outer frame is hermetically connected with the loading base, and the culture plate encapsulates the loading base so that the interior of the loading base is formed

A loading air chamber;

the loading plate is provided with loading platforms corresponding to the loading membranes in number, and the loading membranes are positioned above the loading platforms;

the loading platform is provided with a groove and an air hole, and the groove is connected with the loading air chamber through the air hole;

when the loading air chamber is loaded with negative pressure, the loading membrane is deformed downwards by suction force, and the cell sap on the loading membrane enters the groove along with the loading membrane.

The invention can obtain the following technical effects:

compared with the prior art, the loading device for the three-dimensional force cells can realize two modes of mechanical loading in a three-dimensional space, can realize different mechanical loading waveforms by controlling the loading air chamber, realizes the first mode through one loading plate, realizes the second mode by replacing the loading plate into the loading support plate, the sample rack and the fixed table, has small integral volume and compact and simple structure, and reduces the production cost. The first mode is that the gel is uniformly absorbed into the culture plate, and the cells are uniformly stressed; in the second mode, the supporting plate is uniformly stressed under the air pressure, so that the cell liquid is uniformly stressed, and the cells are uniformly stressed. In addition, the device can be put into a cell constant temperature incubator for use, so that the cell culture with dynamic mechanical loading has feasibility.

Drawings

Fig. 1 is a schematic structural diagram of a loading device according to a first embodiment of the present invention;

fig. 2 is a schematic structural diagram of a loading device according to a second embodiment of the present invention;

FIG. 3 is an exploded view of a three-dimensional force cell loading device according to an embodiment of the present invention;

FIG. 4 is an exploded view of a three-dimensional force cell loading device according to a second embodiment of the present invention;

FIG. 5 is a schematic diagram of a three-dimensional force loading pre-operation state according to an embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating a three-dimensional force loading operation according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a three-dimensional force loading pre-operation state provided by a second embodiment of the present invention;

FIG. 8 is a schematic diagram illustrating a three-dimensional loading operation according to a second embodiment of the present invention;

FIG. 9 is a schematic structural diagram of a transparent cover according to an embodiment of the present invention;

FIG. 10 is a schematic front view of a culture plate according to an embodiment of the present invention;

FIG. 11 is a schematic bottom view of a culture plate according to an embodiment of the present invention;

FIG. 12 is a schematic structural diagram of a seal ring according to an embodiment of the present invention;

FIG. 13 is a schematic front view of a loading plate according to an embodiment of the present invention;

FIG. 14 is a schematic structural view of the bottom surface of a loading plate according to an embodiment of the present invention;

FIG. 15 is a schematic front view of a loading base according to an embodiment of the present invention;

fig. 16 is a schematic bottom structure view of a loading base according to a second embodiment of the present invention;

FIG. 17 is a schematic structural diagram of a pneumatic system provided in the third embodiment of the present invention;

fig. 18 is a flowchart illustrating a control method of a pneumatic system according to a third embodiment of the present invention.

Wherein the reference numerals include: 11. a transparent cover; 12. culturing the plate; 13. a seal ring; 14. a loading plate; 15. loading a base;

16. loading a support plate; 17 a sample holder; 18. a fixed table;

111. chamfering the transparent cover;

120. an outer frame; 121. chamfering the culture plate; 122. a cell culture well; 123. a rib plate on the front surface of the culture plate; 124. loading a film; 125. culturing a plate boss; 126. the rib plate on the back side of the culture plate;

131. an inner ring step; 132. the bottom of the sealing ring;

141. a loading table; 142. a grabbing port; 143. hollowing out; 144. a groove; 145. air holes;

151. a boss of the air chamber; 152. a sealing ring mounting surface; 153. a positive pressure pump connection port; 154. a pressure sensor connector; 155. a negative pressure pump connector; 156. a mounting groove of a clamping tool;

61. a pneumatic device; 62. a pressure sensor; 63. a controller; 64. a cell loading device; 611. a negative pressure solenoid valve; 612. a negative pressure flow valve; 613. a negative pressure stabilizing bottle; 614. a negative pressure filter; 615. a negative pressure pump; 616. a positive pressure pump; 617. a positive pressure filter; 618. a positive pressure stabilizing bottle; 619. a positive pressure flow valve; 620. a positive pressure solenoid valve.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention.

The first embodiment is as follows:

the three-dimensional force cell loading device provided by the embodiment of the invention is used for providing mechanical loading in a three-dimensional space for cells to simulate a single stress condition in a body, and as shown in fig. 1, the direction of an x axis is assumed to be a first direction, the direction of a y axis is assumed to be a second direction, and a z axis is orthogonal to the x axis and the y axis.

As shown in fig. 1-2, the loading device mainly comprises a transparent cover 11 for isolating the external environment, a culture plate 12 for cell culture, a loading plate 14 for assisting the formation of the load, and a loading base 15 for providing a support and a loading air chamber, which are arranged in sequence from top to bottom. The culture plate 12 may be provided with one or more cell culture wells 122, six cell culture wells 122 are exemplified herein, and multiple cell culture wells 122 can solve the problem of multiple experiments being performed simultaneously.

The cell culture well 122 carries cells through a loading membrane 124, and the cell culture well 122 is isolated from the external environment through a transparent cover 11; the loading base 15 is a cavity with an opening at the top; the outer frame 120 is hermetically connected with the loading base 15; the loading plate 14 is provided with loading platforms 141 corresponding to the number of the loading films 124, and the loading films 124 are positioned above the loading platforms 141; the loading platform 141 is provided with a groove 144 and an air hole 145, and the groove 144 is connected with the loading air chamber through the air hole 145; when the loading air chamber is loaded with negative pressure, the loading membrane 124 is deformed downward by the suction force, and the cell sap on the loading membrane 124 enters the groove 144 along with the loading membrane 124.

The culture plate 12 includes an outer frame 120, and a cell culture hole 122 is fixedly connected to the inner portion of the outer frame 120. The cell culture wells 122 are used to support cells via a support membrane 124, and the cell culture wells 122 in the culture plate 12 are 6 separate cell culture compartments in which the cells are cultured. More specifically, the top surfaces of the outer frame 120 and the cell culture wells 122 are equal in height, so that the transparent cover 11 can protect the culture plate 12.

Preferably, the cell culture well 122 is a hollow cylinder with a top and a bottom removed, the inner wall surface of the cylinder is fixedly connected with a circular culture plate boss 125, the culture plate boss 125 extends to the radial inner part of the cylinder, and the function of the culture plate boss 125 is to fix the loading membrane 124 on the cell culture well 122, and the loading membrane 124 forms a seal with the periphery of the cell culture well 122 positioned at the upper part of the culture plate boss 125. And the cell culture hole 122 positioned at the lower part of the lug boss 125 of the culture plate can be sleeved on the top of the loading platform, so that the loading platform and the cell culture hole are conveniently positioned. The inner diameter of the culture plate boss 125 is equal to the outer diameter of the loading platform 141, and the two interference fits form sealing between the culture plate boss 125 and the loading platform 141, so that the loading membrane 124 can be better attached to the groove 144 under negative pressure. The rib plates 123 on the front side and the rib plates 126 on the back side of the culture plate in the culture plate 12 are connected between the outer frame 120 and the cell culture holes and between the two cell culture holes, so that the structural strength is increased; and the gaps between the outer frame 120 and the cell culture holes and between the two cell culture holes are filled, so that no gas passes through the thickness direction of the culture plate 12, and the bottom surface of the culture plate 12 and the cavity of the loading base 15 form a loading gas chamber.

Wherein, the shape of the transparent cover 11 is matched with the shape of the outer frame 120 of the culture plate 12, and the transparent cover 11 is buckled on the culture plate 12 when in use to ensure that the cell culture hole 122 is isolated from the external environment. The outer frame 120 may be a frame having a triangular, square, etc. structure.

The outer frame 120, which is easy to process, is a rectangular frame structure for example. More specifically, as shown in FIGS. 10 to 11, the cross section of the outer frame 120 of the culture plate 12 is a generally open-topped, shell-shaped rectangular parallelepiped surrounding six cell culture wells 122, with the top and bottom removed, and the transparent cover 11 is a shell-shaped rectangular parallelepiped having an open bottom. The transparent cover 11 is sleeved on the top of the culture plate 12, when in use, the transparent cover 11 is pressed downwards by a clamping tool commonly used in the field, the transparent cover and the culture plate are in press contact connection, the transparent cover and the culture plate do not shift relatively, and an additional sealing device is not needed for sealing between the transparent cover and the culture plate.

Preferably, as shown in FIGS. 9-10, a plate chamfer 121 is provided between two sides of the outer frame 120 of the plate 12, i.e., a vertically disposed edge of the outer frame 120 is chamfered. Similarly, a transparent cover chamfer 111 is arranged at the corresponding position of the transparent cover 11, so that one corner of the four corners of the culture plate 12 and the transparent cover 11 is cut off. The culture plate chamfer 121 is matched with the transparent cover chamfer 111, so that the transparent cover cannot move in the horizontal plane, and the transparent cover plays roles in blocking environmental pollution and protecting cells.

Preferably, the outer frame 120 of the culture plate 12 has an L-shaped cross section in the vertical plane, and a step surface is formed on the outside thereof so that the bottom surface of the transparent cover 11 can be easily lapped on the step surface, thereby further protecting the culture plate 12.

The loading base 15 shown in fig. 15-16 is a cavity with an opening at the top, and is a rectangular parallelepiped structure with an opening at the top.

Preferably, the culture plate 12 is connected to the loading base 15 in a sealing manner by a sealing ring 13. As shown in fig. 5 to 6 and 12, the cross-sectional shape of the seal ring 13 is L-shaped, and an inner ring step 131 is formed inside the seal ring. The bottom surface of the outer frame 120 is matched with the inner ring step 131 of the sealing ring 13 to play a role of sealing; the sealing ring mounting surface 152 of the loading base 15 cooperates with the sealing ring bottom 132 of the sealing ring 13 to provide sealing. More specifically, a circle of sealing boss is arranged on the top of the loading base 15, i.e. the sealing ring mounting surface 152, so that a step surface is formed on the inner wall surfaces of the sealing ring mounting surface 152 and the sealing boss for mounting a sealing ring with a matched shape. The inner wall surface of the sealing ring surrounds the outer surface and the bottom surface of the culture plate, the inner wall surface of the sealing boss surrounds the outer wall surface of the sealing ring, and the bottom surface of the sealing ring is lapped on the loading base. So that the gasket 13 is sandwiched between the bottom surface of the culture plate 12 and the top surface of the loading base 15, and between the outer surface of the outer frame 120 and the inner wall surface of the seal projection. Because the loading device is in a negative pressure state in the device when in work, and the sealing ring can be compressed by the clamping tool when the transparent cover is compressed, the sealing ring can play a sealing role without being compressed.

As shown in fig. 13 to 14, the loading plate 14 has a flat plate shape, and the outer dimension of the loading plate is matched with the dimension of the cavity of the loading base 15, and the loading plate is placed inside the loading base 15. The grabbing openings 142 of the loading plate are arranged on two sides of the loading plate and are arc-shaped, the loading tables are arranged on the front surface of the loading plate, six loading tables are arranged in total, grooves of the loading plate are formed in the six loading tables respectively, the loading tables of the loading plate are hollowed out respectively to reduce weight, and four air holes of the loading plate are formed between each groove and each hollow-out. The grabbing opening 142 of the loading plate is arc-shaped, so that the loading plate 14 can be conveniently taken out of the loading base 15, more importantly, a smooth air channel is provided for the loading device, and the grabbing opening of the loading plate is provided with a round angle so as to prevent a hand from being scratched by a sharp angle during operation; the distance between the loading platform 141 of the loading plate 14 and the loading membrane 124 of the growth plate 12 is very close, and it is considered that the two are in contact but do not generate force; the hollow 143 of the loading plate 14 is used for reducing the material consumption of the loading plate 14; the groove 144 of the loading platform is a small container that acts as a cell culture gel when the loading membrane is depressed downward by suction; the air hole 145 of the loading platform is communicated with the air cavity of the groove 144 and the air cavity of the loading base, so that the air of the two cavities can flow mutually; the outer diameter of loading platform 141 of loading plate 14 matches the inner diameter of plate boss 125, forming a tight interference fit, and gas cannot flow through between them. By varying the shape of the groove 144, different gel shapes can be obtained, wherein the stress state of the cells is also different.

After loading, the loading plate 14 may be fixedly connected to the loading base 15, or the loading plate 14 may be detachably connected to the loading base 15.

Preferably, the loading base 15 is provided with an air chamber boss 151 extending toward the inside of the cavity, and the loading plate 14 is movably overlapped on the air chamber boss 151. The air chamber bosses 151 may be provided on a pair of inner wall surfaces of the loading base which are arranged oppositely. The top surface of the air chamber boss 151 is engaged with the bottom surface of the loading plate 14, and the periphery of the loading plate is engaged with the periphery of the loading base to play a role in positioning, so that the loading plate cannot move in the first direction and the second direction. In addition, the air chamber bosses 151 raise the load plate 16 out of contact with the lowermost surface of the load base.

Gas entering the pressurization gas chamber from the positive pressure pump connection port 153 can exit from the negative pressure pump connection port 155; the positive pressure pump connection port 153 is connected to a pipe port of the positive pressure pump as an air inlet of the device, the negative pressure pump connection port 155 is connected to a pipe port of the negative pressure pump as an air outlet of the device, and the pressure sensor connection port 154 is connected to a pressure sensor for monitoring pressure in the device in real time. The positive pressure pump connection port 153, the negative pressure pump connection port 155, the positive pressure pump, the negative pressure pump, the pressure sensor connection port 154 and the pressure sensor form a pneumatic system, and the specific structure can be described later, compared with the prior art that the gas in the gas chamber is singly controlled by only the negative pressure pump, the relationship between the total output gas pressure value of the positive pressure pump and the negative pressure pump and the time can be controlled, so that the gas pressure of various waveforms, such as static state, positive rotation, E-heart type, P-heart type, triangle, rectangle and various custom waveforms, can be simulated, and the stress condition of cells can be simulated more abundantly.

The loading device of the embodiment comprises a mechanical structure part, a pneumatic system and a control system, wherein the mechanical structure part is connected with the pneumatic part, and the control system controls the pneumatic system to provide the expected positive pressure and negative pressure for the mechanical structure part so as to simulate air pressure with various waveforms. The mechanical structure part comprises a transparent cover 11, a culture plate 12, a sealing ring 13, a loading plate 14 and a loading base 15. The control system is prior art in the field of pneumatic pumps and will not be described in detail here. FIG. 5 is a schematic diagram of the three-dimensional force cell loading device of this embodiment before operation, where the distance between the loading membrane 124 in the loading plate 12 and the loading platform 141 of the loading plate 14 is very close, and it can be considered that the two are in contact, but no stress is generated, and the outer diameter of the loading platform 141 of the loading plate 14 and the inner diameter of the projection 125 of the loading plate are the same, and they form a seal, and gas cannot flow through them. Fig. 6 is a schematic diagram of the first three-dimensional force cell loading device in operation, when the cavity of the device is at negative pressure, the loading membrane 124 on the loading boss 141 of the loading plate 14 is forced downwards, and the cell sap on the loading membrane 124 enters the groove along with the loading membrane, so that the cell in the cell sap is forced in three dimensions.

Example two:

the three-dimensional force cell loading device provided by the embodiment of the invention is used for providing mechanical loading in a three-dimensional space for cells so as to simulate a single stress condition in a body, and provides two three-dimensional force cell loading modes. The installation and structure of the transparent cover 11, the culture plate 12, the sealing ring 13 and the loading base 15 of the present embodiment are the same as those of the present embodiment. In contrast, the loading base 15 has a universal structure on the basis that the loading plate 14 and the loading base 15 are separable, and whether to be connected with the loading plate 14 or not can be selected. And a loading support plate 16 for pressing the culture solution together with the sample holder 17 upward, a sample holder 17 for placing the culture solution, a fixing table 18 for positioning the sample holder, and a clamping tool for fixing the transparent cover 11 are installed on the cell culture hole 122.

Preferably, a clamping tool mounting groove 156 is formed in the bottom surface of the loading base 15, so that a clamping space is provided for a clamping tool. The clamping tool is the prior art in the field and is not described in detail herein.

Wherein, the loading support plate 16 is a hard round thin sheet and is arranged on the loading membrane 124 of the culture plate 12, and the loading support plate 16 supports the cell culture solution and the sample rack 17 to move upwards together under the action of pressure; the sample holder 17 is an elastic circular ring, has good elastic strain and recovery capability, and the cell culture solution is placed in the sample holder 17; the fixed platform 18 is a hard cylinder and is arranged between the sample frame 17 and the transparent cover 11, the upper surface and the lower surface of the fixed platform 18 are respectively contacted and matched with the sample frame 17 and the transparent cover 11, and the upper surface of the fixed platform 18 and the transparent cover 11 are basically not stressed before the device does not form positive pressure and negative pressure. The loading plate 14 is detached from the loading base 15, when a loading air chamber is loaded with positive pressure, the loading support plate 16, the sample holder 17 and the fixed table 18 form a culture cavity together, the culture cavity is used for placing cell culture solution, and the transparent cover 11 is pressed on the culture plate 12 through the clamping tool.

Fig. 7 is a schematic diagram showing a state before the second three-dimensional force cell loading device works, wherein the loading support plate 16 is placed on the loading membrane 124 and supports the cell culture solution and the sample holder 17, the cell culture solution is placed in the sample holder 17, the sample holder 17 is not deformed, the fixed stage 18 is installed between the sample holder 17 and the transparent cover 11, the upper surface and the lower surface of the fixed stage 18 are respectively in contact fit with the sample holder 17 and the transparent cover 11, and the upper surface of the fixed stage 18 and the transparent cover 11 are not substantially stressed.

Fig. 8 is a schematic diagram of the second three-dimensional force cell loading device in operation, when the pressure in the device is positive, the loading membrane moves upward under the action of the pressure to drive the cell culture fluid on the loading support plate 16 and the sample holder 17 to move upward together, the sample holder 17 is deformed by extrusion, so that the inner diameter of the annular cylinder of the sample holder 17 is reduced, the height of the annular cylinder is reduced, the cell culture fluid is subjected to the force in the three-dimensional space, and at this time, the fixing table 18 plays a role in sealing and positioning with the sample holder 17.

The loading device of this embodiment uses a set of transparent cover 11, culture plate 12, sealing ring 13, and loading base 15. When the loading plate 14 is arranged on the loading base 15, a three-dimensional force loading mode is provided; the loading plate 14 is not installed, the loading support plate 16, the sample rack, the fixed table 18 and the clamping tool are installed on the culture plate 12, and a second three-dimensional force loading mode is provided. The embodiment has the advantages of simple structure and cost reduction. The two provided modes of applying space three-dimensional force to the cells cultured in vitro enable the cells to be stressed more uniformly, the structural complexity of the device is simplified, meanwhile, the cost of carrying out multiple groups of experiments is greatly reduced, and the experiment period is shortened.

The first three-dimensional force cell loading device is realized by negative pressure, different cell stress modes are required in biological cell culture, different gel shapes can be obtained by changing the shapes of loading plate holes (in the invention, the loading plate holes are in a long groove shape), and the stress states of cells are different;

the second three-dimensional force cell loading device is realized by positive pressure, and directly extrudes cell sap without gel. Two different stress modes are selected for cell experiments.

Example three:

the pneumatic system of this embodiment can apply pressure to the load chamber without changing the structure of the mechanical structure part of the first two embodiments. Referring to FIGS. 17-18, a pneumatic system for cell loading includes: a pneumatic device 61 for adjusting the pressure in the cell loading device, a pressure sensor 62 for monitoring the pressure in the cell loading device in real time, and a controller 63 for receiving, processing and sending signals.

The pneumatic device 61 is connected to the loading base 15, and includes a negative pressure pump 615, a negative pressure filter 614, a negative pressure stabilizing bottle 613, a negative pressure flow valve 612, and a negative pressure solenoid valve 611, which are connected in sequence by a pipe joint and a gas pipe, and the negative pressure solenoid valve 611 is connected to the negative pressure pump connection port 155.

The pneumatic device 61 further comprises a positive pressure pump 616, a positive pressure filter 617, a positive pressure stabilizer 618, a positive pressure flow valve 619 and a positive pressure solenoid valve 620 which are sequentially connected by a pipe joint and a gas pipe, wherein the positive pressure solenoid valve 620 is connected with the positive pressure pump connecting port 153.

The positive pressure pump connection port 153 and the negative pressure pump connection port 155 of the loading device are respectively connected with the positive pressure electromagnetic valve and the negative pressure electromagnetic valve through pipe joints and air pipes.

The positive pressure pump 616 and the negative pressure pump 615 are air sources, the pneumatic device 61 provides a required power source by the air sources, pure, dry and stable air flow is obtained from the air flow in the air sources through a filter and a pressure stabilizing bottle, then the air flow is adjusted through a flow valve and a solenoid valve to obtain air flow with required flow, and finally the air flow enters the loading base 15. The air from the positive pressure pump or the negative pressure pump firstly passes through the corresponding filter and then enters the corresponding pressure stabilizing bottle, so that moisture and impurities in the air are prevented from being accumulated in the pressure stabilizing bottle; the solenoid valves connected in sequence are closer to the loading base 15 than the flow valves because: the electromagnetic valve is used for opening or cutting off the air path, the flow valve is used for adjusting the size of the opening of the air path, and when the electromagnetic valve is closed, any action of the flow valve has no influence on the pressure in the loading base 15.

The pressure sensor 62 is connected to a pressure sensor connection port 154 of the loading base 15, and can monitor the pressure inside the loading base 15 in real time and convert the pressure into an electrical signal to be transmitted to the controller 63.

The controller 63 is connected to two flow valves, two solenoid valves and also to the pressure sensor 62. The controller 63 receives the electric signal from the pressure sensor 62, processes the waveform of the target pressure and converts it into a corresponding electric signal, and transmits a control signal to the flow valve and the solenoid valve in the pneumatic device 61.

The pneumatic device can adjust the pressure in the loading base 15 to pressurize, decompress and pressure-maintaining the device. The control method monitors the pressure in the cell loading device at any time and feeds the pressure back to the controller, error compensation is added compared with open-loop control, so that the control precision is higher, pressure relief operation is carried out on the cell loading device before the system finishes working, the device cannot be operated under pressure, and the safety and the reliability of the system during experiment are ensured.

A method of controlling a pneumatic system for cell loading, as shown in fig. 18, comprising the steps of:

A1、

s10, starting a pneumatic system;

s20, inputting a waveform of the required pressure within the time from the initial time to the termination time, uniformly dividing the time from the initial time to the termination time into a plurality of time periods according to a preset width value, setting a target pressure for each time period by the controller 13, wherein the target pressure is used for fitting the pressure corresponding to the time period; for example, the desired pressure waveform is a sine curve, the waveform is sequentially divided equally in time, and the average of the pressures for each time period may be selected as the target pressure. Converting the corresponding target pressure into an electric signal, wherein the preset width value is preferably 10 ms;

a2, S30, the controller 63 judges whether the target pressure of the current time period is increased or decreased compared with the target pressure of the previous time period; if the current time period is the first time period, the target pressure in the current time period is increased or decreased compared with the pressure of 0 value, and it is easy to think that the target pressure is not related to the pressure value in the loading base 15;

A3、

s311, if the pressure is increased, closing the negative pressure electromagnetic valve 611 and the negative pressure flow valve 612, and opening the positive pressure electromagnetic valve 620 and the positive pressure flow valve 619;

s312, if the pressure is reduced, closing the positive pressure electromagnetic valve 620 and the positive pressure flow valve 619, and opening the negative pressure electromagnetic valve 611 and the negative pressure flow valve 612;

a4, according to the judgment result of A3 or A7, adjusting the opening of the positive pressure flow valve 619 or the negative pressure flow valve 612 as required to adjust the pressure in the loading base 15;

a5, the controller 13 judges whether the end time is reached at present, that is, whether the loading process is finished, if yes, step A8 is executed; if not, executing the step A6;

a6, the controller 63 executes the next time slot and judges whether the target pressure of the time slot of the step A5 needs to be changed, if yes, the step A2 is executed; if not, step A7 is executed to control the valve according to the actual and expected pressure difference if the pressure does not change;

a7, the controller 63 receives the electric signal from the pressure sensor 62, compares it with the electric signal converted from the target pressure in the time period in step a6 to obtain the difference between the electric signal of the pressure sensor 62 and the electric signal of the target pressure in the time period in step a6, and if the absolute value of the difference is less than or equal to a predetermined error, then step a5 is executed;

if the difference is smaller than zero and the absolute value of the difference is larger than the preset error, the pressure is increased, the negative pressure electromagnetic valve 611 and the negative pressure flow valve 612 are closed, the positive pressure electromagnetic valve 620 and the positive pressure flow valve 619 are opened, and the step A4 is executed;

if the difference is greater than zero and the absolute value of the difference is greater than the predetermined error, the pressure is reduced, the positive pressure electromagnetic valve 620 and the positive pressure flow valve 619 are closed, the negative pressure electromagnetic valve 611 and the negative pressure flow valve 612 are opened, and step a4 is executed;

a8, unloading the pressure in the loading base 15, opening the device to observe the cells and stopping the pneumatic system.

The example is described as a linear waveform diagram, in which the time varies from the initial time 0 to the end time 20ms, the pressure is kept at 2KPa, the preset width value is 10ms, and the preset error epsilon is 0.1 KPa.

B1、

S10, starting a pneumatic system;

s20, inputting a waveform of required pressure, and sequentially dividing time into a first time period and a second time period in sequence, wherein the width of each time period is 10 ms; assigning a target pressure to each time segment to fit a design value of the pressure for the time segment, where the pressure for each time segment is 2 KPa; the controller 63 converts the target pressure corresponding to each time period into an electric signal;

b2, S30 and the controller 63 judge that the current time period is the first time period, and the target pressure of the current time period is increased compared with the 0-value pressure;

b3 and S311, if pressurization is needed, closing the negative pressure electromagnetic valve 611 and the negative pressure flow valve 612, and opening the positive pressure electromagnetic valve 620 and the positive pressure flow valve 619;

b4, adjusting the opening of the positive pressure flow valve 619 to adjust the pressure in the loading base 15;

b5, the controller 63 finishes executing the current time period, determines that the ending time is not reached at present, that is, the second time period needs to be executed, and replaces the step B6;

b6, the controller 63 replaces the second time period, and judges whether the value of the target pressure in the second time period compared with the target pressure in the previous time period needs to be changed, if not, the opening sizes of the positive pressure electromagnetic valve 620 and the positive pressure flow valve 619 are not changed, and step B7 is replaced;

b7, the controller 63 receives the electric signal from the pressure sensor 62, compares the electric signal with the target pressure in the second time period, and replaces the step B8 if the difference is larger than the preset error;

b8, judging whether pressure is required to be increased or reduced according to the difference controller, and adjusting the opening of the positive pressure flow valve 619 or the negative pressure flow valve 612 as required to adjust the pressure in the loading base 15 so that the difference is smaller than or equal to a preset error;

b9, the controller 63 judges whether the ending time is reached at present, the system has already executed the second time period to reach the ending time, and replaces the step B10;

b10, unloading the pressure in the loading base 15, opening the device to observe cells conveniently, and stopping the pneumatic system.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

While embodiments of the present invention have been shown and described above, it should be understood that the above embodiments are exemplary and should not be taken as limiting the invention. Variations, modifications, substitutions and alterations of the above-described embodiments may be made by those of ordinary skill in the art without departing from the scope of the present invention.

The above embodiments of the present invention should not be construed as limiting the scope of the present invention. Any other corresponding changes and modifications made according to the technical idea of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. The three-dimensional force cell loading device is characterized by comprising a transparent cover (11), a culture plate (12), a loading plate (14) and a loading base (15) which are sequentially arranged;

the culture plate (12) comprises an outer frame (120) and at least one cell culture hole (122), wherein the cell culture hole (122) is fixedly connected inside the outer frame (120);

the cell culture well (122) comprises a loading membrane (124) arranged at the bottom of the well, the loading membrane (124) is used for loading cells, and the cell culture well (122) is isolated from the external environment through the transparent cover (11);

the loading base (15) is a cavity with an opening at the top;

the outer frame (120) is connected with the loading base (15) in a sealing way, and the culture plate (12) encapsulates the loading base (15) so that a loading air chamber is formed inside the loading base (15);

the loading plate (14) is provided with loading platforms (141) corresponding to the number of the loading films (124), and the loading films (124) are positioned above the loading platforms (141);

a groove (144) and an air hole (145) are formed in the loading platform (141), and the groove (144) is connected with the loading air chamber through the air hole (145);

when the loading air chamber is loaded with negative pressure, the loading membrane (124) is deformed downwards by suction force, and cell sap on the loading membrane (124) enters the groove (144) along with the loading membrane (124).

2. The three-dimensional force cell loading device according to claim 1, wherein the culture plate (12) further comprises a circular ring-shaped culture plate boss (125), the culture plate boss (125) is fixedly arranged on the inner wall surface of the cell culture hole (122), and the loading membrane (124) encapsulates the culture plate boss (125);

the inner diameter of the culture plate boss (125) matches the outer diameter of the loading platform (141) such that a seal is formed between the culture plate boss (125) and the loading platform (141).

3. The device for three-dimensional force cell loading according to claim 1, wherein the loading plate (14) and the loading base (15) are separable.

4. The device for loading three-dimensional force cells according to claim 3, wherein the loading base (15) is provided with a gas chamber boss (151) extending toward the inside of the cavity, and the loading plate (14) is movably overlapped on the gas chamber boss (151).

5. The three-dimensional force cell loading device according to claim 3, further comprising a loading support plate (16), a sample holder (17), a fixing table (18) and a clamping tool;

the loading support plate (16) is a circular sheet placed on the loading membrane (124);

the sample holder (17) is an elastic circular ring and is arranged on the loading support plate (16);

the bottom surface of the fixed table (18) is contacted with the sample frame (17), and the top surface of the fixed table (18) is contacted with the transparent cover (11);

when the loading air chamber loads positive pressure, the loading plate (14) is not arranged on the loading base (15), the loading support plate (16), the sample frame (17) and the fixed table (18) jointly form a culture cavity, and the clamping tool is used for enabling the transparent cover (11) to tightly press the culture plate (12).

6. The device for loading the three-dimensional force cells according to claim 5, wherein a clamping tool mounting groove (156) is formed on the bottom surface of the loading base (15).

7. The device for three-dimensional force cell loading according to claim 1, wherein the device further comprises a sealing ring (13) interposed between the culture plate (12) and the loading base (15);

a sealing boss surrounding the sealing ring (13) is arranged at the top of the loading base (15);

the cross section of the sealing ring (13) is L-shaped, so that the sealing ring (13) is clamped between the bottom surface of the culture plate (12) and the top surface of the loading base (15), and is clamped between the outer surface of the culture plate (12) and the inner wall surface of the sealing boss.

8. The device for loading three-dimensional force cells according to claim 1, further comprising a pneumatic system comprising a pneumatic device (61), a pressure sensor (62) and a controller (63);

the loading air chamber is connected with a positive pressure pump connecting port (153) and a negative pressure pump connecting port (155) in parallel;

the pneumatic device (61) comprises a negative pressure pump (615), a negative pressure filter (614), a negative pressure stabilizing bottle (613), a negative pressure flow valve (612) and a negative pressure electromagnetic valve (611) which are connected in sequence, and the negative pressure electromagnetic valve (611) is connected with the negative pressure pump connecting port (155);

the pneumatic device (61) further comprises a positive pressure pump (616), a positive pressure filter (617), a positive pressure stabilizing bottle (618), a positive pressure flow valve (619) and a positive pressure electromagnetic valve (620) which are sequentially connected, and the positive pressure electromagnetic valve (620) is connected with the positive pressure pump connecting port (153);

the pressure sensor (62) is used for monitoring the pressure value in the loading gas chamber and converting the pressure value into an electric signal to be transmitted to the controller (63);

the controller (63) is respectively electrically connected with the negative pressure flow valve (612), the negative pressure electromagnetic valve (611), the positive pressure flow valve (619) and the positive pressure electromagnetic valve (620).

9. The three-dimensional force cell loading device as claimed in claim 1, wherein the outer frame (120) is a rectangular frame structure, and the transparent cover (11) is sleeved on the top of the culture plate (12);

and a culture plate chamfer (121) is arranged between two side faces of the outer frame (120), and a transparent cover chamfer (111) matched with the culture plate chamfer (121) is arranged on the transparent cover (11).

10. A method of pneumatic system control by the pneumatic system of claim 8, comprising the steps of:

a1, starting the pneumatic system, inputting a required pressure waveform from initial time to termination time, averagely dividing the initial time to the termination time into a plurality of time periods according to a preset width value, and setting a target pressure for each time period, wherein the target pressure is used for fitting the pressure of the corresponding waveform in the time period; the controller (63) converting the value of the target pressure into an electrical signal;

a2, the controller (63) judges whether the target pressure in the current time period is increased or reduced compared with the target pressure in the last time period; if the current time period is the first time period, judging whether the target pressure in the current time period is increased or reduced compared with the pressure of 0 value;

a3, if the pressure is increased, closing the negative pressure electromagnetic valve (611) and the negative pressure flow valve (612), and opening the positive pressure electromagnetic valve (620) and the positive pressure flow valve (619); if the pressure is reduced, closing the positive pressure electromagnetic valve (120) and the positive pressure flow valve (619), and opening the negative pressure electromagnetic valve (611) and the negative pressure flow valve (612);

a4, according to the judgment result of the step A3 or the step A7, adjusting the opening of the corresponding positive pressure flow valve (619) or negative pressure flow valve (612) as required to adjust the pressure in the cavity of the loading base (15);

a5, the controller (63) judges whether the current time is the termination time, if yes, the step A8 is executed; if not, executing the step A6;

a6, the controller (63) executes the next time period, whether the target pressure of the current time period and the target pressure of the time period of the step A5 are changed or not is judged, and if yes, the step A2 is executed; if not, executing the step A7;

a7, the controller (63) receiving the electric signal from the pressure sensor (62), comparing with the target pressure converted electric signal for the time period in the step A6, if the absolute value of the difference is less than or equal to a predetermined error, executing the step A5;

if the difference is smaller than zero and the absolute value of the difference is larger than a preset error, the pressure is increased, the negative pressure electromagnetic valve (611) and the negative pressure flow valve (612) are closed, the positive pressure electromagnetic valve (620) and the positive pressure flow valve (619) are opened, and the step A4 is executed;

if the difference is greater than zero and the absolute value of the difference is greater than a preset error, determining that the pressure is reduced, closing the positive pressure electromagnetic valve (620) and the positive pressure flow valve (619), opening the negative pressure electromagnetic valve (611) and the negative pressure flow valve (612), and executing the step A4;

a8, unloading the pressure in the loading base (15).