Living body detection device and method for hormone in plant leaf with replaceable electrode
阅读说明：本技术 一种可更换电极的植物叶片内激素的活体检测装置及其方法 (Living body detection device and method for hormone in plant leaf with replaceable electrode ) 是由 龙拥兵 施玉峰 徐海涛 杨林鑫 巫彬芳 栗云鹏 周华 姚志杰 邓海东 兰玉彬 于 2020-12-30 设计创作，主要内容包括：本发明公开了一种可更换电极的植物叶片内激素的活体检测装置及其方法,装置包括可调支撑架、连接件、活体采样机构以及电化学信号检测仪；可调支撑架通过连接件与活体采样机构相连接的同时,与连接件配合调节活体采样机构所处的高度；电化学信号检测仪与活体采样机构连接；本发明采用三电极结构的电化学传感法,以非插入的方式在植物叶片上实现活体检测；另外,通过活体采样机构采样,使得根据需要检测激素的种类,快速对电极进行更换,以实现对不同特异性植物激素的检测；最后采用电化学信号检测仪和电极可分离的设计,工作电极可以单独进行加工和二次修饰,从而提高了电化学检测性能,降低了生产成本和使用成本。(The invention discloses a device and a method for in-vivo detection of hormone in plant leaves with replaceable electrodes, wherein the device comprises an adjustable support frame, a connecting piece, an in-vivo sampling mechanism and an electrochemical signal detector; the adjustable support frame is connected with the living body sampling mechanism through the connecting piece and is matched with the connecting piece to adjust the height of the living body sampling mechanism; the electrochemical signal detector is connected with the living body sampling mechanism; the invention adopts an electrochemical sensing method with a three-electrode structure to realize in-vivo detection on plant leaves in a non-insertion way; in addition, the living body sampling mechanism is used for sampling, so that the types of hormones can be detected according to the needs, and the electrodes can be replaced quickly, so that the detection of different specific phytohormones can be realized; and finally, by adopting the design that the electrochemical signal detector and the electrode can be separated, the working electrode can be independently processed and secondarily modified, so that the electrochemical detection performance is improved, and the production cost and the use cost are reduced.)
1. A living body detection device of hormone in plant leaves with replaceable electrodes is characterized by comprising an adjustable support frame (1), a connecting piece (4), a living body sampling mechanism and an electrochemical signal detector; the adjustable support frame (1) is connected with the living body sampling mechanism through the connecting piece (4), and is matched with the connecting piece (4) to adjust the height of the living body sampling mechanism;
the living body sampling mechanism comprises a sampling base (2), a hormone sampling piece (3), an electrode connecting column (5), a blade pressing piece (6) and a main body connecting frame (7);
the hormone sampling piece (3) is placed on the sampling base (2), and the electrode is placed on the hormone sampling piece (3);
the main body connecting frame (7) is provided with a first inner cavity and a second inner cavity, the electrode connecting column (5) and the blade pressing piece (6) are respectively arranged in the first inner cavity and the second inner cavity, and the three components form a fixed connecting structure;
the fixed connecting structure is inserted into the sampling base (2) on which the hormone sampling piece (3) and the electrode are placed, and forms a detachable structure with the hormone sampling piece (3), the sampling base (2) and the electrode; the blade pressing piece (6) is close to and positioned above the hormone sampling piece (3);
the electrochemical signal detector is connected with an electrode in the living body sampling mechanism through an electrode connecting column (5).
2. The in-vivo hormone detection device for plant leaves with replaceable electrodes as claimed in claim 1, wherein the adjustable support frame (1) comprises a support base (1-1) and a support column (1-2);
the supporting base (1-1) is a round cake-shaped supporting base;
the support column (1-2) is vertically arranged above the support base (1-1) and fixedly connected with the middle of the support base (1-1), and clamping teeth (1-3) are uniformly laid on one side face of the support column (1-2) along the extending direction of the support column.
3. The living body test device for hormones in plant leaves with replaceable electrodes in claim 2, wherein the connecting piece (4) comprises a hoop frame (4-1), a connecting part (4-2) and a clamp spring (4-3);
the area of the cross section of the hoop frame (4-1) is matched with that of the cross section of the supporting column (1-2), so that the hoop is sleeved on the supporting column (1-2);
one end of the connecting part (4-2) is connected with one side surface of the hoop frame (4-1), and the other end of the connecting part is connected with the side surface of the sampling base (2);
the clamp spring (4-3) is installed on the other side face of the hoop frame (4-1), the direction of the side face is the same as that of the side face of the support column (1-2) paved with the clamp teeth (1-3), and the height of the in-vivo sampling mechanism is adjusted through the cooperation of the clamp spring (4-3) and the clamp teeth (1-3).
4. The device for the in-vivo detection of hormones in plant leaves with replaceable electrodes as claimed in claim 3, wherein the sampling base (2) comprises a sampling base plate (2-1) and a mounting connection part (2-2);
the sampling bottom plate (2-1) is divided into a front area and a rear area, the front area is provided with a groove (2-3) for placing a hormone sampling piece (3), and the rear area is an electrode connecting platform (2-4);
the installation connecting parts (2-2) are integrally formed at the left side and the right side of the sampling bottom plate (2-1), and the installation connecting parts (2-2) are provided with main body slots (2-5) for inserting the main body connecting frames (7).
5. The device for in vivo detection of hormones in plant leaves with replaceable electrodes as claimed in claim 4, wherein the hormone sampling member (3) is placed in a groove (2-3) of a sampling base plate (2-1), and the upper surface of the hormone sampling member is provided with a hormone sampling groove (3-1) and three electrode grooves (3-2); one end of the electrode groove (3-2) is communicated with the hormone sampling groove (3-1), and the other end of the electrode groove extends towards the electrode connecting platform (2-4) and is directly communicated with the electrode connecting platform (2-4).
6. The in-vivo hormone detection device of plant leaves with replaceable electrodes as claimed in claim 5, wherein the electrodes comprise a working electrode, a reference electrode and a counter electrode, one end of each electrode extends into the hormone sampling groove (3-1), the middle part of each electrode is arranged in the corresponding electrode groove (3-2), and the other end of each electrode extends onto the electrode connecting platform (2-4) after passing through the corresponding electrode groove (3-2);
the middle part of the working electrode is sealed by an insulating pipe sleeve;
the reference electrode is a silver-silver chloride electrode;
the counter electrode is a platinum electrode.
7. The device for in vivo detection of hormones in plant leaves with replaceable electrodes as claimed in claim 6, wherein the side and bottom surfaces of the first cavity are respectively provided with a side hole and a bottom hole;
the electrode connecting column (5) comprises a first contact column (5-1), a first spring (5-2), a connecting column (5-3) and a lead (5-4);
one end of the first spring (5-2) is connected with one end of the first contact column (5-1), and the other end of the first spring is connected with the top of the first inner cavity of the main body connecting frame (7);
the lead (5-4) penetrates through the first spring (5-2) and is connected between the first contact column (5-1) and the binding post (5-3);
the other end of the first contact column (5-1) penetrates through a bottom hole of the first inner cavity and is in contact with the electrode;
one end of the binding post (5-3) far away from the first contact post (5-1) penetrates through the side hole of the first inner cavity and is connected with the electrochemical signal detector.
8. The device for the in vivo detection of hormones in plant leaves with replaceable electrodes as claimed in claim 7, wherein the second inner cavity is provided with an upper end hole passing through the top of the main body connecting frame (7);
the blade pressing piece (6) comprises a pressing plate (6-1), a second abutting column (6-2), a second spring (6-3) and a control column (6-4);
the pressing plate (6-1) is horizontally arranged;
the second contact posts (6-2) and the control posts (6-4) are fixed on the upper surface of the pressing plate (6-1), and the control posts (6-4) are located between the two second contact posts (6-2);
one end of the second spring (6-3) is connected with the top end of the second contact column (6-2), and the other end of the second spring is connected with the top of a second inner cavity of the main body connecting frame (7) to provide a vertical force for the second spring (6-3);
the upper end of the control column (6-4) passes through the upper end hole of the second inner cavity.
9. A method for in vivo detection of hormones in plant leaves with replaceable electrodes as claimed in claim 8, comprising the steps of:
s1, installing a living body sampling mechanism;
s2, placing the adjustable support frame beside the plant to be detected, and adjusting the height of the living body sampling mechanism through the matching of a snap spring on the connecting piece and a snap tooth on the support column to enable the height of the living body sampling mechanism to be consistent with the height of the plant leaf to be detected;
s3, dripping a buffer solution into the hormone sampling groove of the hormone sampling piece to fill the hormone sampling groove with the buffer solution;
s4, covering the plant leaves to be detected on the surface of the hormone sampling piece, and enabling the leaf pressing piece to be pressed downwards along the extending direction of the second inner cavity through manually controlling the upper end of the control column, so that the plant leaves to be detected are fixed;
s5, puncturing a plurality of holes on the surface of the plant leaf to be detected above the hormone sampling groove by using a needle, and waiting for 10 seconds to 20 minutes to enable juice in the leaf to permeate and diffuse into the buffer solution through the punctured holes;
and S6, connecting the electrochemical signal detector to three binding posts of the in-vivo sampling mechanism, turning on the electrochemical signal detector to detect electrochemical information, and determining the hormone concentration.
10. The method for the in-vivo test of hormones in plant leaves with replaceable electrodes according to claim 9, wherein the step S1 is implemented by installing a biopsy sampling mechanism as follows:
s1-1, placing the hormone sampling piece into the groove of the sampling base;
s1-2, putting the required working electrode, reference electrode and counter electrode into the electrode groove corresponding to the hormone sampling element;
s1-3, inserting a fixed connection structure consisting of an electrode connection column, a blade pressing piece and a main body connection frame into the sampling base, and forming the living body sampling mechanism.
Technical Field
The invention relates to the technical field of electrochemical detection, in particular to a living body detection device and method for hormones in plant leaves, and the device and method can replace electrodes.
Background
The plant hormone is a micro-molecular organic matter synthesized by plants, is used as a signal molecule, and can generate a remarkable regulation and control effect on the growth and development of the plants at an extremely low concentration. Known plant hormones mainly include auxin, abscisic acid, gibberellin, cytokinin, ethylene, brassin, jasmone, salicylic acid, strigolactone and the like. The plant hormones regulate the growth and development of the plant and the environmental adaptation processes, and the plant hormones are independent of each other and cooperate with each other to regulate the growth and development processes of the plant, such as seed germination, vegetative growth, reproductive growth, embryonic development, seed maturation, dormancy and the like, and the adaptation to biotic and abiotic environmental stresses in the growth period. Since the discovery, the plant hormone has been widely applied to the fields of agricultural production and the like, and great social and economic benefits are generated.
The content of phytohormone in plant is very low, and is in the range of 0.1-50ng/g fresh weight. Phytohormones are sensitive to external conditions such as light, temperature and oxidants, and interfere with the background of complex metabolites in plant tissues, so that the determination method needs high sensitivity and specificity. At present, the quantitative detection and analysis methods of phytohormones mainly comprise a spectrum method, a liquid chromatography method, a mass spectrometry method, a capillary electrophoresis method and the like. However, the sampling of the above quantitative analysis method is an ex vivo treatment method, and the loss of the sample to be detected inevitably occurs during the extraction, purification and detection processes, and the freezing and extraction processes are complicated and long in time, and thus short-term or real-time sample detection cannot be realized. Among the detection means, the electrochemical sensor detection method has the advantages of convenient operation, cheap required instruments, quick response, high sensitivity, good selectivity, continuous dynamic monitoring, no need of complex sample pretreatment process and the like, and is suitable for being applied to the aspect of plant living body detection.
However, in the research of the electrochemical sensor on the hormone detection in the plant leaves, the leaves to be detected are usually picked up and then detected, and the in vivo detection cannot be realized. Different working electrodes are needed to be used for detecting different types of phytohormones, the electrodes of the existing packaged sensor cannot be replaced, and the use cost is high. Most of the electrochemical sensors based on the screen printing electrode are disposable, the detection performance of the electrochemical sensors is greatly reduced after the electrochemical sensors are used for one time, the electrochemical sensors cannot be reused, the detection area of the working electrode is prepared in batches by adopting printing slurry, secondary modification cannot be carried out to improve the electrochemical detection performance, and the electrodes cannot be replaced to realize detection of different specific phytohormones. The thickness of the plant leaf is relatively small, usually 0.5mm or less, and it is difficult to detect the thickness of the plant leaf by inserting the leaf into the probe electrode. Therefore, the plant leaf hormone living body detection device with the replaceable electrode has a good application prospect.
Disclosure of Invention
The invention aims to overcome the problem of corner transition of a robot, and provides a living body detection device of hormone in plant leaves, which can replace electrodes, can improve the detection efficiency and reduce the detection cost while realizing the living body detection of the plant hormones such as auxin, salicylic acid, gibberellin, abscisic acid and the like in the plant leaves.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
a living body detection device of hormone in plant leaves with replaceable electrodes comprises an adjustable support frame, a connecting piece, a living body sampling mechanism and an electrochemical signal detector; the adjustable support frame is connected with the living body sampling mechanism through the connecting piece and is matched with the connecting piece to adjust the height of the living body sampling mechanism;
the living body sampling mechanism comprises a sampling base, a hormone sampling piece, an electrode connecting column, a blade pressing piece and a main body connecting frame;
the hormone sampling piece is placed on the sampling base, and the electrode is placed on the hormone sampling piece;
the main body connecting frame is provided with a first inner cavity and a second inner cavity, the electrode connecting column and the blade pressing piece are respectively arranged in the first inner cavity and the second inner cavity, and the electrode connecting column, the blade pressing piece and the blade pressing piece form a fixed connecting structure;
the fixed connecting structure is inserted into the sampling base on which the hormone sampling piece and the electrode are placed, and forms a detachable structure with the hormone sampling piece, the sampling base and the electrode; the blade pressing piece is close to and positioned above the hormone sampling piece;
the electrochemical signal detector is connected with an electrode in the living body sampling mechanism through an electrode connecting column.
Further, the adjustable support frame comprises a support base and a support column;
the supporting base is a cake-shaped supporting base;
the support column is vertically installed above the support base and fixedly connected with the middle of the support base, and clamping teeth are uniformly paved on one side face of the support column along the extending direction of the support column.
Further, the connecting piece comprises a hoop frame, a connecting part and a clamp spring;
the area of the cross section of the hoop frame is matched with that of the cross section of the support column, so that the hoop is sleeved on the support column;
one end of the connecting part is connected with one side surface of the hoop frame, and the other end of the connecting part is connected with the side surface of the sampling base;
the clamp spring is installed on the other side face of the hoop frame, the direction of the side face is the same as the direction of the side face of the support column with the laid clamp teeth, and the height of the living body sampling mechanism is adjusted through the matching of the clamp spring and the clamp teeth.
Further, the sampling base comprises a sampling bottom plate and an installation connecting part;
the sampling bottom plate is divided into a front area and a rear area, the front area is provided with a groove for placing a hormone sampling piece, and the rear area is an electrode connecting platform;
the installation connecting portion integrated into one piece is in the sampling bottom plate left and right sides, and installation connecting portion are equipped with the main part slot that is used for inserting the main part link.
Furthermore, the hormone sampling piece is placed in a groove of the sampling bottom plate, and a hormone sampling groove and three electrode grooves are formed in the upper surface of the hormone sampling piece; one end of the electrode groove is communicated with the hormone sampling groove, and the other end of the electrode groove extends towards the electrode connecting platform and is directly communicated with the electrode connecting platform; the electrode groove has a length of 5-20mm, a width of 0.1-3mm and a depth of 0.1-1mm according to different electrodes; the hormone sampling groove has a length of 5-10mm, a width of 3-10mm and a depth of 0.1-1mm according to different hormones to be sampled.
Furthermore, the electrodes comprise working electrodes, reference electrodes and counter electrodes, one ends of the three electrodes extend into the hormone sampling grooves, the middle parts of the three electrodes are arranged in the corresponding electrode grooves, and the other ends of the three electrodes extend onto the electrode connecting platform after penetrating through the corresponding electrode grooves;
the middle part of the working electrode is sealed by an insulating pipe sleeve;
the reference electrode is a silver-silver chloride electrode;
the counter electrode is a platinum electrode.
Furthermore, a side hole and a bottom hole are respectively formed in the side surface and the bottom surface of the first inner cavity;
the electrode connecting column comprises a first contact column, a first spring, a connecting column and a lead;
one end of the first spring is connected with one end of the first contact column, and the other end of the first spring is connected with the top of the first inner cavity of the main body connecting frame;
the lead passes through the first spring and is connected between the first contact column and the binding post;
the other end of the first contact column penetrates through a bottom hole of the first inner cavity and is in contact with the electrode;
one end of the binding post, which is far away from the first butting post, penetrates through the side hole of the first inner cavity and is connected with the electrochemical signal detector.
Furthermore, the second inner cavity is provided with an upper end hole which penetrates through the top of the main body connecting frame;
the blade pressing piece comprises a pressing plate, a second contact column, a second spring and a control column;
the pressing plate is horizontally placed;
the second contact columns and the control column are fixed on the upper surface of the pressing plate, and the control column is located between the two second contact columns;
one end of the second spring is connected with the top end of the second contact column, and the other end of the second spring is connected with the top of the second inner cavity of the main body connecting frame to provide a vertical force for the second spring;
the upper end of the control column penetrates through an upper end hole of the second inner cavity.
To achieve the above object, the present invention additionally provides a method for a device for in vivo detection of hormones in plant leaves, the electrodes of which are replaceable, comprising the steps of:
s1, installing a living body sampling mechanism;
s2, placing the adjustable support frame beside the plant to be tested, and adjusting the height of the in-vivo sampling mechanism through the matching of a snap spring on the connecting piece and a snap tooth on the support column to enable the height of the in-vivo sampling mechanism to be consistent with the height of the leaf to be tested;
s3, dripping a buffer solution into the hormone sampling groove of the hormone sampling piece to fill the hormone sampling groove with the buffer solution;
s4, covering the plant leaves to be detected on the surface of the hormone sampling piece, and enabling the leaf pressing piece to be pressed downwards along the extending direction of the second inner cavity through manually controlling the upper end of the control column, so that the plant leaves to be detected are fixed;
s5, puncturing a plurality of holes on the surface of the plant leaf to be detected above the hormone sampling groove by using a needle, and waiting for 10 seconds to 20 minutes to enable juice in the leaf to permeate and diffuse into the buffer solution through the punctured holes;
and S6, connecting the electrochemical signal detector to three binding posts of the in-vivo sampling mechanism, turning on the electrochemical signal detector to detect electrochemical information, and determining the hormone concentration.
Further, the specific process of installing the biopsy sampling mechanism in step S1 is as follows:
s1-1, placing the hormone sampling piece into the groove of the sampling base;
s1-2, putting the required working electrode, reference electrode and counter electrode into the electrode groove corresponding to the hormone sampling element;
s1-3, inserting a fixed connection structure consisting of an electrode connection column, a blade pressing piece and a main body connection frame into the sampling base, and forming the living body sampling mechanism.
Compared with the prior art, the principle and the advantages of the scheme are as follows:
1. the method adopts an electrochemical sensing method with a three-electrode structure to realize in-vivo detection on the plant leaves in a non-insertion mode.
2. The detachable living body sampling mechanism is adopted for sampling, so that the types of hormones can be detected as required, the electrodes can be replaced rapidly, and the detection of different specific phytohormones can be realized.
3. By adopting the design that the electrochemical signal detector and the electrode can be separated, the working electrode can be independently processed and secondarily modified, so that the electrochemical detection performance is improved, and the production cost and the use cost are reduced.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the services required for the embodiments or the technical solutions in the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a schematic structural diagram of a device for in vivo detection of hormones in plant leaves with replaceable electrodes (electrochemical signal detector is omitted);
FIG. 2 is a schematic structural diagram of a sampling base in the device for in vivo detection of hormones in plant leaves with replaceable electrodes according to the present invention;
FIG. 3 is a schematic view showing a hormone sampling member in the device for in vivo detection of hormones in plant leaves with replaceable electrodes according to the present invention;
FIG. 4 is a schematic structural diagram of an electrode connecting column in the device for in vivo detection of hormones in plant leaves with replaceable electrodes;
FIG. 5 is a schematic view showing the construction of a blade presser in the device for in vivo measurement of hormones in plant leaves with replaceable electrodes according to the present invention;
FIG. 6 is a schematic structural view showing the assembly of the main body connecting frame with the electrode connecting column and the leaf pressing member in the device for in vivo detection of hormones in plant leaves with replaceable electrodes according to the present invention;
FIG. 7 is a diagram showing the result of detecting auxin in cucumber seedling leaves by the device for in vivo detection of hormones in plant leaves with replaceable electrodes.
Detailed Description
The invention will be further illustrated with reference to specific examples:
as shown in FIG. 1, the living body detection device for hormones in plant leaves with replaceable electrodes is used for detecting cucumber seedling leaf auxin.
The device comprises an adjustable support frame 1, a connecting piece 4, a living body sampling mechanism and an electrochemical signal detector; the adjustable support frame 1 is connected with the living body sampling mechanism through the connecting piece 4 and is matched with the connecting piece 4 to adjust the height of the living body sampling mechanism.
Specifically, the adjustable support frame 1 comprises a support base 1-1 and a support column 1-2;
the supporting base 1-1 is a round cake-shaped supporting base;
the supporting column 1-2 is vertically arranged above the supporting base 1-1 and fixedly connected with the middle part of the supporting base 1-1, and clamping teeth 1-3 are uniformly laid on one side surface of the supporting column 1-2 along the extending direction of the supporting column.
Specifically, the connecting piece 4 comprises a hoop frame 4-1, a connecting part 4-2 and a clamp spring 4-3;
the area of the cross section of the hoop frame 4-1 is matched with that of the cross section of the supporting column 1-2, so that the hoop is sleeved on the supporting column 1-2;
one end of the connecting part 4-2 is connected with one side surface of the hoop frame 4-1, and the other end is connected with the side surface of the sampling base 2;
the clamp spring 4-3 is arranged on the other side face of the hoop frame 4-1, the direction of the side face is the same as that of the side face of the support column 1-2 with the clamp teeth 1-3 laid on the side face, and the clamp spring 4-3 is matched with the clamp teeth 1-3, so that the height of the connecting piece 4 is locked.
Specifically, the living body sampling mechanism comprises a sampling base 2, a hormone sampling piece 3, an electrode connecting column 5, a blade pressing piece 6 and a main body connecting frame 7;
as shown in fig. 2, the sampling base 2 comprises a sampling base plate 2-1 and an installation connecting part 2-2;
the sampling bottom plate 2-1 is divided into a front area and a rear area, the front area is provided with a groove 2-3 for placing a hormone sampling piece 3, and the rear area is an electrode connecting platform 2-4;
the installation connecting parts 2-2 are integrally formed at the left and right sides of the sampling bottom plate 2-1, and the installation connecting parts 2-2 are provided with main body slots 2-5 for inserting the main body connecting frames 7.
As shown in fig. 3, the upper surface of the hormone sampling piece 3 is provided with a hormone sampling groove 3-1 and three electrode grooves 3-2; one end of the electrode groove 3-2 is communicated with the hormone sampling groove 3-1, and the other end extends towards the electrode connecting platform 2-4 and is directly communicated with the electrode connecting platform 2-4.
Specifically, the electrodes comprise working electrodes, reference electrodes and counter electrodes, one ends of the three electrodes extend into the hormone sampling grooves 3-1, the middle parts of the three electrodes are arranged in the corresponding electrode grooves 3-2, and the other ends of the three electrodes extend onto the electrode connecting platforms 2-4 after penetrating through the corresponding electrode grooves 3-2;
the working electrode adopts carbon fiber wires modified by carbon nano tubes and chloroauric acid, and the middle part of the working electrode is sealed by an insulating pipe sleeve;
the reference electrode is a silver-silver chloride electrode;
the counter electrode is a platinum electrode.
Specifically, the main body connecting frame 7 is provided with a first inner cavity and a second inner cavity, the side surface and the bottom surface of the first inner cavity are respectively provided with three side holes and three bottom holes, and the second inner cavity is provided with an upper end hole penetrating through the top of the main body connecting frame 7;
specifically, as shown in fig. 4, the electrode connecting column 5 comprises a first contact column 5-1, a first spring 5-2, a connecting column 5-3 and a lead 5-4;
one end of the first spring 5-2 is connected with one end of the first contact column 5-1, and the other end is connected with the top of the first inner cavity of the main body connecting frame 7;
the lead 5-4 penetrates through the first spring 5-2 and is connected between the first contact column 5-1 and the binding post 5-3;
the other end of the first contact column 5-1 penetrates through a bottom hole of the first inner cavity;
one end of the binding post 5-3 far away from the first contact post 5-1 penetrates through the side hole of the first inner cavity.
Specifically, as shown in FIG. 5, the vane press 6 includes a pressing plate 6-1, a second abutment post 6-2, a second spring 6-3, and a control post 6-4;
the pressing plate 6-1 is horizontally placed;
the second contact posts 6-2 and the control posts 6-4 are fixed on the upper surface of the pressing plate 6-1, and the control posts 6-4 are located between the two second contact posts 6-2;
one end of a second spring 6-3 is connected with the top end of the second contact column 6-2, and the other end of the second spring is connected with the top of a second inner cavity of the main body connecting frame 7 to provide a vertical force for the second spring 6-3;
the upper end of the control column 6-4 passes through the upper end hole of the second inner cavity.
In the above structure, as shown in fig. 6, the electrode connecting column 5, the leaf presser 6 and the body connecting frame 7 constitute a fixed connecting structure, and the plant leaf hormone is not detached or attached (previously attached) during the biopsy.
In addition, the fixed connection structure is inserted into the sampling base 2 on which the hormone sampling piece 3 and the electrode are placed, and forms a detachable structure with the hormone sampling piece 3, the sampling base 2 and the electrode (namely, the hormone sampling piece 3, the sampling base 2, the electrode and the fixed connection structure can be detached or installed according to the living body detection requirement of the plant leaf hormone);
after the biopsy mechanism is mounted and shaped,
the blade pressing piece 6 is close to and positioned above the hormone sampling piece 3; the bottom end of the first contact post 5-1 is contacted with the electrode, and one end of the binding post 5-3, which penetrates through the side hole of the first inner cavity, is connected with the electrochemical signal detector, so that the electrode is communicated with the electrochemical signal detector.
The following is the process of detecting cucumber seedling leaf auxin by the device for detecting the hormone in the plant leaf with the replaceable electrode in the embodiment:
s1, installing a living body sampling mechanism:
the method comprises the following steps:
s1-1, putting the hormone sampling piece 3 into the groove 2-3 of the sampling base 2;
s1-2, putting the needed working electrode, reference electrode and counter electrode into the electrode groove corresponding to the hormone sampling piece 3;
s1-3, inserting a fixed connection structure consisting of an electrode connecting column 5, a blade pressing piece 6 and a main body connecting frame 7 into the sampling base 2, and forming the living body sampling mechanism.
S2, after the in-vivo sampling mechanism is installed, the adjustable support frame 1 is placed beside the cucumber seedling, the height of the in-vivo sampling mechanism is adjusted through the matching of the snap spring 4-3 on the connecting piece 4 and the snap teeth 1-3 on the support columns 1-2, and the height of the in-vivo sampling mechanism is made to be consistent with the height of the cucumber seedling blades;
s3, dripping PBS buffer solution into the hormone sampling groove 3-1 of the hormone sampling piece 3 to fill the hormone sampling groove 3-1 with the PBS buffer solution;
s4, covering the cucumber seedling leaves on the surface of the hormone sampling piece 3, and manually controlling the upper end of the control column 6-4 to enable the leaf pressing piece 6 to press downwards along the extending direction of the second inner cavity so as to fix the cucumber seedling leaves;
s5, puncturing 3 holes on the surface of each cucumber seedling leaf above the hormone sampling groove 3-1 by using a needle, and waiting for 30 seconds to enable juice in the leaves to permeate and diffuse into PBS buffer solution through the punctured holes;
and S6, connecting the electrochemical signal detector to three binding posts of the in-vivo sampling mechanism, turning on the electrochemical signal detector to detect electrochemical information, and determining the hormone concentration, wherein the detection result is shown in figure 7.
In the embodiment, a three-electrode structure electrochemical sensing method is adopted, and living body detection is realized on cucumber seedling leaves in a non-insertion mode; in addition, the living body sampling mechanism is used for sampling, so that the types of hormones can be detected according to the needs, and the electrodes can be replaced quickly, so that the detection of different specific phytohormones can be realized; and finally, by adopting the design that the electrochemical signal detector and the electrode can be separated, the working electrode can be independently processed and secondarily modified, so that the electrochemical detection performance is improved, and the production cost and the use cost are reduced.
The above-mentioned embodiments are merely preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, so that variations based on the shape and principle of the present invention should be covered within the scope of the present invention.