Automatic equipment for surface pretreatment and measurement of single nano-pore channel of glass

Abstract

The invention discloses automatic equipment for surface pretreatment and measurement of a single nano-pore channel of glass. The equipment comprises surface pretreatment equipment, measuring equipment and a control module for controlling the operation of the two equipment. The surface pretreatment equipment comprises a PID (Proportion Integration Differentiation) temperature control module, an ultrasonic treatment module, a circulating liquid change module, a hot air drying module and a lifting rotating module, and can be used for sequentially completing piranha solution cleaning, pure water cleaning, ethanol cleaning and drying; measurement equipment integrates a picoammeter, ultrasonic treatment and an Ag-AgCl reference electrode system, and automatically fits a curve and calculates the aperture in combination with electrochemical measurement. The equipment coordinates actions of all the modules through an automatic control program, and automation of the whole surface pretreatment-measurement process is achieved. According to the device, manual operation errors can be eliminated, the surface pretreatment efficiency and the measurement consistency are improved, steady-state limiting current is obtained through fitting of a CV curve and substituted into a formula to calculate the pore diameter value of the nano pore channel, and the device is suitable for high-throughput treatment of batch samples.

Description

Technical Field

[0001] This invention relates to the field of nanomaterial preparation and characterization technology, and in particular to an automated device for surface pretreatment and pore size measurement of glass single nanopores, specifically including surface pretreatment equipment and measurement equipment, which can improve surface pretreatment efficiency and pore size measurement accuracy. Background Technology

[0002] Glass nanopores are core components in nanofluidic devices, single-molecule sensors, and biomimetic ion channel research, with their pore size (1-100 nm) directly affecting the ion transport characteristics of the devices. The traditional template-based fabrication process involves four steps: first, a sinusoidal alternating voltage is applied to a platinum wire to etch a nanoscale platinum needle tip; then, a glass capillary is fused at high temperature and the platinum needle tip is encapsulated, followed by mechanical polishing to prepare a platinum disk electrode; finally, the platinum needle tip is completely etched using aqua regia for more than 10 hours to form a conical glass nanopore. Considering that aqua regia is sufficient to etch away the platinum wire tip, this method assumes that the pore size is equal to the radius of the platinum disk electrode and is based on the steady-state diffusion current formula. Indirect calculation of aperture ( For steady-state diffusion current, , , , These are the charge number, Faraday constant, diffusion coefficient, and solution concentration, respectively. (where is the radius of the aperture).

[0003] However, traditional methods suffer from the following significant drawbacks: First, the surface pretreatment process is complex and high-risk. Before measurement, the pores must be thoroughly cleaned and dried using hot Piranha solution (concentrated sulfuric acid:H2O2=3:1), ultrapure water, and ethanol, taking over an hour per sample. The handling of high-temperature and highly corrosive reagents poses a safety risk. Second, human error is significant: manual surface pretreatment and sample measurement easily introduce human bias, and multiple measurements are required to obtain an average, resulting in low overall efficiency. Third, the data is not intuitive: existing equipment only outputs voltage and current values, requiring manual calculation of steady-state limiting current values ​​and their substitution into formulas to calculate the pore size. Real-time feedback is not possible, and the results rely heavily on operator experience. These drawbacks pose serious challenges to the standardization, repeatability, and large-scale application of traditional methods, necessitating technological innovation to improve the accuracy and automation of measurements during nanopore preparation. Summary of the Invention

[0004] The purpose of this invention is to provide an automated device for pretreatment and measurement of glass single-nanopore surface, comprising: a surface pretreatment device, a measuring device, and a control module for controlling the operation of both, wherein...

[0005] The surface pretreatment equipment includes a first sample rotation switching stage, which has a first linkage shaft and is fixed to a first Z-axis lifting stage; a container for a super oxidizing cleaning agent, a container for pure water cleaning, a container for ethanol cleaning, and a hot air drying module are arranged around the first linkage shaft at intervals; the first sample rotation switching stage rotates under the action of the first sample rotation switching stage and sequentially enters the cleaning agent container, the container for pure water cleaning, the container for ethanol cleaning, and the hot air drying module.

[0006] The measuring device includes a second sample rotation switching stage and a measuring container. The second sample rotation switching stage has a second linkage shaft, which is fixed to a second Z-axis lifting platform. The second sample rotation switching stage rotates under the action of the second sample rotation switching stage and enters the measuring container. A conductive platform is provided on the second sample rotation switching stage. The continuity of the circuit is achieved by conducting the platinum disk electrode through copper wire to the sleeve with the glass capillary tube inserted, then through contact to the conductive platform, then through the conductive spring to the copper plate above the shielding box, and finally connecting to the positive electrode of the picoammeter. The reference electrode is fixedly connected to the negative electrode of the picoammeter.

[0007] The first and second sample rotation switching stages have identical structures, each including a slider, belt, drive wheel, driven wheel, guide post, fixed plate, and two motors. The fixed plate is mounted on a second base, with a horizontally extending section at its upper end. A guide post is vertically positioned between the horizontal section and the base, with its upper end passing through the horizontal section. A slider is fitted into the middle of the guide post. Rotation of the guide post drives the slider to move up and down. A motor is fixed on the slider, and its output shaft is linked to the linkage shaft of the sample rotation switching stage, so that rotation of the motor's output shaft drives rotation of the first linkage shaft. The upper end of the guide post is fixed to the driven wheel, and a drive wheel is located beside the driven wheel, with a belt connecting the drive wheel and the driven wheel. The drive wheel is linked to the output shaft of the other motor.

[0008] Furthermore, the first rotary switching stage and / or the second sample rotary switching stage are provided with a plurality of sample insertion holes in the circumferential direction near the edge for inserting a sleeve containing a glass capillary tube.

[0009] Furthermore, the pure water cleaning container is equipped with an ultrasonic transducer, which is connected to the bottom of the first peristaltic pump. The first peristaltic pump is connected to the first solenoid valve. The first solenoid valve is a three-way valve, with one end connected to water, one end connected to the pure water cleaning container, and the other end discharging waste liquid.

[0010] Furthermore, the ethanol cleaning container is equipped with an ultrasonic transducer, and its bottom is connected to a second peristaltic pump, which is connected to a second solenoid valve. The second solenoid valve is a three-way valve, with one end connected to ethanol, one end connected to the ethanol cleaning container, and the other end discharging waste liquid.

[0011] Furthermore, the conductive platform overlaps with the second sample rotation switching stage.

[0012] Furthermore, a spring is provided at the top center of the second sample rotary switching stage.

[0013] Furthermore, the measuring container is located inside the ultrasonic container, and the bottom of the ultrasonic container is provided with an ultrasonic transducer.

[0014] Furthermore, the side of the fixed plate is provided with a guide rail, and the extension of the slider is provided with a guide portion corresponding to the guide rail on the side facing the fixed plate.

[0015] This invention also provides an automated method for surface pretreatment and pore size measurement of glass single nanopores, using the aforementioned equipment, and comprising the following steps:

[0016] Step S1: Fix the polished glass single nanopore channel using a sample container and place it on the first sample rotation switching stage. Fill the container with Piranha solution into the super oxidizing cleaning agent container; clean the container with pure water; and fill the ethanol cleaning container with pure water and ethanol respectively. The first sample rotation switching stage first descends to immerse the glass single nanopore channel in the Piranha solution at high temperature, then rises, rotates, and descends to allow the glass single nanopore channel to enter the pure water cleaning container for pure water cleaning; it then rises, rotates, and descends again to allow the glass single nanopore channel to enter the ethanol cleaning container for ethanol cleaning; finally, it rises, rotates, and descends to enter the hot air drying module for drying, and then rises, rotates, and returns to its original position after completion.

[0017] In step S2, the sample that has undergone surface pretreatment in step S1 is inserted into the socket of the second sample rotary switching stage. The second sample rotary switching stage rotates and descends to insert the sample into the ultrasonic container for ultrasonication, and then measurement is performed.

[0018] Furthermore, in step S2, an external picoammeter is connected to the automated aperture measurement equipment.

[0019] This invention provides an automated device for pretreatment and measurement of glass single nanopore surfaces. This device solves the problems of low efficiency, significant human error in measurement process, and inability to directly convert current data into pore size values ​​caused by manual operation in the existing glass nanopore surface pretreatment process.

[0020] The equipment consists of a surface pretreatment device and a measuring device, which are automated and coordinated throughout the entire process via a control module. The surface pretreatment device includes a PID heating module, an ultrasonic treatment module, a circulating liquid exchange module, a hot air drying module, a lifting module, a rotating module, and a control module. It sequentially performs high-temperature immersion in a hot piranha solution (concentrated sulfuric acid and 30% hydrogen peroxide in a 3:1 volume ratio), rinsing with ultrapure water, ethanol cleaning, and hot air drying. The PID heating module uses a cast aluminum heating plate, a solid-state relay, and a PID algorithm to achieve precise temperature control, maintaining the piranha solution (concentrated sulfuric acid and 30% hydrogen peroxide in a 3:1 volume ratio) at a highly active state of 80-100°C. The ultrasonic treatment module consists of an ultrasonic transducer and an ultrasonic generator, producing ultrasonic waves of 20-100 kHz to enhance the cleaning effect. The circulating liquid exchange module uses a peristaltic pump and a three-way solenoid valve to perform multiple liquid inflows and outflows according to a program to complete the cleaning. The hot air drying module uses a PTC heater and a fan to achieve rapid drying.

[0021] The measuring device integrates a picoammeter, an ultrasonic processing module, a circulating fluid exchange module, a lifting module, a rotation module, an Ag-AgCl reference electrode system, and a control module. It automatically acquires cyclic voltammetry curves through electrochemical measurements and obtains the steady-state diffusion current value using a highly automated and robust pore size fitting algorithm, which is then substituted into the formula. The aperture value is calculated. The ultrasonic processing module consists of an ultrasonic transducer and an ultrasonic generator, which can generate ultrasonic waves of 20-100 kHz to remove air bubbles on the surface of the glass nanopores and improve measurement accuracy.

[0022] The lifting module in both devices consists of a first motor driver and a Z-axis lifting platform. The Z-axis lifting platform is mechanically connected to the rotating module. The first motor driver drives the lifting platform to move vertically along the Z-axis, thereby adjusting the longitudinal position of the rotating module. The rotating module includes a stage and a second motor driver. A sample rotating disk on the stage is used to fix the sample container. The second motor driver drives the sample rotating disk to rotate at a preset angle, realizing multi-station sample switching. The control module synchronously controls the rotation speed of the rotating module and the movement trajectory of the lifting module through an embedded program, and is connected to a human-machine interface panel or a remote control terminal.

[0023] In some embodiments, the sample container is a metal conductive sleeve with locking clamps at both ends, used to clamp the glass single nanopore and ensure conductivity stability during electrochemical measurements; the first motor driver and the main control circuit of the control module of the lifting module are integrated inside the equipment base, and the human-machine interface panel is embedded on the surface of the base, forming a compact integrated structure.

[0024] In some embodiments, the control device is a human-machine interface panel, an industrial control screen, or a remote device.

[0025] Compared to traditional manual operation and discrete equipment, the core innovation of this invention lies in: achieving efficient and safe surface pretreatment of corrosive reagents through PID temperature control and liquid circulation technology; ensuring sample consistency during surface pretreatment and measurement using a lifting-rotating sample switching system; and embedding electrochemical measurement and pore size fitting algorithms into the control module to directly output pore size values, eliminating errors from manual calculations. This equipment significantly improves the efficiency and data repeatability of glass nanopore processing, making it suitable for the batch preparation and characterization of high-throughput nanodevices.

[0026] The surface pretreatment equipment precisely maintains the piranha solution at an active temperature of 80-100°C using a PID temperature control module (cast aluminum heating plate). Combined with the splash-proof design of the protective container (containing a glass container inside the piranha solution), the risk of manual contact with highly corrosive reagents is completely eliminated. The rotary switching table automates the soaking, washing, and drying processes via a Z-axis lifting platform, allowing operators to complete the entire process with only initial sample loading. The pretreatment and measurement equipment coordinate their actions through a unified control module, achieving "washing-drying-measurement". Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the surface pretreatment equipment of the present invention;

[0028] Figure 2 This is a front view of the interior of the surface pretreatment equipment of the present invention;

[0029] Figure 3 This is a rear view of the interior of the surface pretreatment equipment of the present invention;

[0030] Surface pretreatment equipment reference numerals

[0031] 1. First sample rotary switching stage; 1-1 First linkage shaft; 1-2 Sample insertion hole; 2. First Z-axis lifting stage; 3. PID control heating block; 4. Pure water cleaning container; 5. Ultrasonic transducer; 6. Ethanol cleaning container; 7. Peristaltic pump; 8. Solenoid valve; 9. Hot air drying module; 10. Power supply; 11. First outer shell; 12. Switch; 13. Human-machine interface screen; 31. Protective container; 32. First base.

[0032] Figure 4 This is a schematic diagram of the measuring device of the present invention;

[0033] Figure 5 This is an internal view of the measuring device of the present invention;

[0034] Figure 6 This is a schematic diagram of the Z-axis lifting platform.

[0035] Measuring equipment reference numerals

[0036] 14. Second sample rotary switching stage; 14-1 Second rotary linkage shaft; 14-2 Sample insertion hole; 15. Second Z-axis lifting stage; 16. Ultrasonic container; 17. Reference electrode; 18. Ultrasonic transducer; 19. Conductive platform; 20. Conductive spring; 21. Power supply; 22. Second outer shell; 23. Switch; 24. Industrial control panel; 25. Shielding box; 26. Flip cover; 27. Second base.

[0037] Z-axis lifting platform (attached symbol)

[0038] 33-Third motor 34-Slider 35-Fourth motor 36-Belt 37-Driving pulley 38-Driven pulley

[0039] 39-Guide post 40-Fixing plate 40-1 Horizontal section Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that the described embodiments are only some examples of the present invention, and not all implementation methods. All other embodiments obtained by those skilled in the art based on the technical solutions of the present invention without creative effort are within the protection scope of the present invention.

[0041] In describing this invention, the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicating orientation or positional relationships, are based on the orientation of the device structure shown in the accompanying drawings. They are used solely for the convenience of describing this invention and are not intended to limit the actual orientation or operating direction of the device or component, nor should they be construed as limitations on this invention. The terms "first," "second," etc., are used only to distinguish the objects of description and do not indicate technical importance or priority.

[0042] Unless otherwise explicitly defined, the terms “installation,” “setting,” “socketing,” “connection,” etc., used in this invention should be interpreted broadly. For example, “connection” includes, but is not limited to, mechanical fixing, detachable assembly, electrical signal interconnection, and linkage directly or indirectly through an intermediate medium. The specific meaning can be determined based on the conventional understanding of those skilled in the art and the actual application scenario.

[0043] Reference Figures 1-3 This embodiment provides an automated device for pretreatment of glass single nanopore surface, including a PID heating module, an ultrasonic treatment module, a circulating liquid exchange module, a hot air drying module, a lifting module, a rotation module, and a control module.

[0044] Figure 1 This is an overall appearance drawing. Figure 2 and Figure 3This is an internal view after removing the outer casing 10. The first sample rotation switching stage 1 is fixed to the first Z-axis lifting stage 2. The sample rotation switching stage 1 is disc-shaped, positioned above the upper surface of the outer casing 11. A first linkage shaft 1-1 is located downwards in the center of the disc. The first linkage shaft 1-1 is linked to the first Z-axis lifting stage, thereby driving the sample rotation switching stage 1 to move up and down and rotate. The rotation switching stage 1 has multiple sample insertion holes 1-2 for inserting glass capillaries.

[0045] The first Z-axis lifting platform 2 and the second Z-axis lifting platform 15 have the same structure. See [link / reference] Figure 6 Taking the second Z-axis lifting platform 15 as an example, the second Z-axis lifting platform 15 includes a third motor 33, a slider 34, a fourth motor 35, a belt 36, a driving wheel 37, a driven wheel 38, a guide post 39, and a fixing plate 40. The fixing plate 40 is vertically mounted on the second base 27, with a horizontally extending horizontal portion 40-1 at its upper end. A guide post 39 is vertically mounted between the horizontal portion 40-1 and the base, and the upper end of the guide post 39 passes upward through the horizontal portion 40-1. A slider 34 (see [reference]) is sleeved in the middle of the guide post 39. Figure 5 The slider 34 has an extension 34-1 on its back, and a guide post 39 is inserted into the extension 39-1. The guide post 39 and the slider 34 can be coupled in various ways, such as by a lead screw or a threaded connection, so that the rotation of the guide post 39 can drive the slider 34 to move up and down. The side of the fixing plate 40 is provided with a guide rail, and the extension 34-1 of the slider 34 facing the fixing plate 40 has a guide part corresponding to the guide rail, so that the slider can slide smoothly up and down.

[0046] A third motor 33 is fixedly mounted on the slider 34. The output shaft of the third motor 33 is linked with the first linkage shaft 1-1, so that the rotation of the output shaft of the third motor 33 can drive the first linkage shaft 1-1 to rotate. The linkage method is, for example, a fixed connection.

[0047] The upper end of the guide post 39 is fixed to a driven wheel 38, and a driving wheel 37 is provided next to the driven wheel 38. The driving wheel 37 and the driven wheel 38 are connected by a belt 36. The driving wheel 37 is fixedly connected to the output shaft of the fourth motor 35. The fourth motor 35 is fixed to the bottom of the horizontal part 40-1.

[0048] When the third motor 33 operates, the first linkage shaft 1-1 is driven, thereby rotating the sample rotary switching stage 1. When the fourth motor 35 operates, it drives the driving wheel 37, which in turn drives the driven wheel 38 to rotate via the belt 36, thereby driving the guide post 39 to rotate. The rotation of the guide post 39 then drives the slider 34 to move up and down, thereby moving the entire sample rotary switching stage 1 up and down.

[0049] A protective container 31, a pure water cleaning container 4, an ethanol cleaning container 6, and a hot air drying module 9 are arranged at intervals around the first linkage shaft 1-1. The protective container 31 is a detachable cylinder fixed to the outer shell 11, and a cast aluminum heating plate 3 is located at the bottom of the cylinder. The pure water cleaning container 4, the ethanol cleaning container 6, and the hot air drying module 9 pass through the outer shell 11 from the bottom upwards. A human-machine interface screen 13 and a switch 12 are located on the front of the outer shell; the human-machine interface screen 13 is electrically connected to the internal functional units.

[0050] The outer casing 11 contains a first base 32, a first linkage shaft 1-1 is mounted on the first Z-axis lifting platform 2, and a cast aluminum heating plate 3 is mounted inside the protective container 31. The first Z-axis lifting platform 2 contains a first motor, a second motor, and corresponding linkage mechanisms to control the lifting of the rotating shaft 1-1. As mentioned above, the first Z-axis lifting platform 2 and the second Z-axis lifting platform 15 have the same structure.

[0051] The pure water cleaning container 4 is equipped with an ultrasonic transducer 5, and its bottom is connected to a peristaltic pump 7. The peristaltic pump 7 is connected to a solenoid valve 8. The solenoid valve is a three-way valve, with one end connected to water (external water container), one end connected to the pure water cleaning container 4, and the other end discharging waste liquid (external discharge).

[0052] The ethanol cleaning container 6 is also equipped with an ultrasonic transducer 5, and its bottom is connected to another peristaltic pump 7, which is connected to another solenoid valve. The other solenoid valve is also a three-way valve, with one end connected to ethanol (external ethanol storage container), one end connected to the ethanol cleaning container 6, and the other end discharging waste liquid (external discharge).

[0053] The hot air drying module 9 has a cylindrical shell, inside which a PTC heater and a fan are installed for drying.

[0054] The heating module consists of a splash-proof protective container 31 and a cast aluminum heating plate 3. The ultrasonic treatment module consists of two ultrasonic transducers 5 and an ultrasonic generator located inside the outer shell 11, which can generate ultrasonic waves of 20-100 kHz to enhance the cleaning effect. The circulating liquid exchange module consists of a pure water cleaning container 4 and an ethanol cleaning container 6, as well as two sets of peristaltic pumps 7 and two sets of solenoid valves 8. It performs multiple liquid injections and discharges according to a program. The liquid is stored in the outer container and connected to a three-way valve through a silicone tube, and then driven by the peristaltic pump. Waste liquid is discharged from the equipment through a pump, completing the cleaning process. The hot air drying module 9 uses a PTC heater and a fan to achieve rapid drying. The lifting module consists of a Z-axis lifting platform 2 and a first motor. The rotation module includes a stage and a second motor. The first sample rotating disk 1 on the stage is used to fix the sample container. The control module is controlled through the human-machine interface panel 13, which consists of a display screen and an LCD touch screen. As a simple alternative to this embodiment, the control module can also be remotely controlled by transmitting signals from a computer.

[0055] In the specific implementation of the surface pretreatment process, the polished glass single nanopores are fixed in a sample container and placed on the first sample rotation switching stage 1. A glass container, such as a beaker, is placed inside the protective container 31, and a piranha solution (concentrated sulfuric acid and 30% hydrogen peroxide in a volume ratio of 3:1) is added to the beaker. Pure water is used to clean the container 4, and pure water and ethanol are respectively injected into the ethanol cleaning container 6. The first sample rotation switching stage 1 first descends to immerse the glass single nanopores in the piranha solution at high temperature, then rises, rotates, and descends to allow the glass single nanopores to enter the pure water cleaning container 4 for pure water cleaning; it then rises, rotates, and descends again to allow the glass single nanopores to enter the ethanol cleaning container 6 for ethanol cleaning; finally, it rises, rotates, and descends to enter the hot air drying module 9 for drying.

[0056] The piranha solution in the glass container can be manually replaced after multiple uses, while pure water and ethanol can be replaced using a pump (the automatic replacement of water and ethanol during the cleaning process can be set by parameters). Waste liquid is discharged from the equipment via a pump. Specifically, the surface pretreatment mode must first be selected on the manual interaction panel 13. The control system offers two modes: automatic surface pretreatment mode and manual surface pretreatment mode. The parameters include: heating time and temperature, pure water cleaning time and corresponding number of liquid replacements, ethanol cleaning time and corresponding number of liquid replacements, and final drying time. If automatic mode is selected, the corresponding parameters must be entered; otherwise, the default parameters will be used. After confirmation, click "Start," and the lifting and rotating modules will sequentially execute the piranha solution (concentrated sulfuric acid and 30% hydrogen peroxide volume ratio 3:1) high-temperature soaking, ultrapure water rinsing, ethanol cleaning, and hot air drying processes. If manual surface pretreatment mode is selected, a single step must be selected, the corresponding parameters set, the height and position of the turntable manually adjusted, and the process started. Wait for the process to complete.

[0057] Reference Figures 4-5 This embodiment provides an automated device for measuring the pore size of a single nanopore in glass. It includes a second housing 22, the upper part of which is a metal shielding box 25. The metal shielding box 25 includes four side panels (front, back, left, and right) and a top flip cover 26. An industrial control screen 24 and a switch 23 are located on the front of the housing.

[0058] The second housing 22 contains a second base 27, on which a second Z-axis lifting platform 15 is mounted. A second rotary linkage shaft 14-1 of the second sample rotary switching stage 14 is inserted into the middle of the second Z-axis lifting platform 15. The connection relationship between the second rotary linkage shaft 14-1 and the Z-axis lifting platform 15 is as follows: Figure 6 As shown in the figure, it can rotate and drive the second sample rotary switching stage 14 to rotate and move up and down.

[0059] The second sample rotary switching stage 14 is equipped with a conductive platform 19, which overlaps with the second sample rotary switching stage 14. A second lifting shaft 14-1 is located downward at the bottom center of the second sample rotary switching stage 14, and a spring 20 is located at the top center. Near the edge of the second sample rotary switching stage 14, there are multiple sample insertion holes 14-2 for inserting sleeves containing glass capillaries in a circumferential direction.

[0060] The second base 27 is also provided with an ultrasonic container 16, the bottom of which is provided with an ultrasonic transducer 18, and the upper part is connected to a reference electrode 17.

[0061] The automated aperture measurement device includes an external picoammeter, an ultrasonic processing module, a lifting module, a rotation module, an Ag-AgCl reference electrode system, and a control module. The ultrasonic processing module consists of an ultrasonic transducer 18 and an ultrasonic generator located inside the housing 22, capable of generating 20-100 kHz ultrasonic waves to remove air bubbles from the surface of the glass nanopores, improving measurement accuracy. The lifting module consists of a Z-axis lifting stage 15 and a fourth motor. The rotation module includes a stage and a third motor, with a second sample rotation switching disk 14 on the stage for fixing the sample container. The control module is operated via an industrial control screen 24, which consists of a Linux development board and an LCD touchscreen. As a simple alternative to this embodiment, the control module can also be remotely controlled via a computer. The control module is a mature existing technology and is not the focus of this invention.

[0062] During the specific implementation of the measurement process, after Figure 1 The sample pretreated by the surface pretreatment automated equipment is inserted into the insertion hole 14-2 of the second sample rotary switching stage 14. The second sample rotary switching stage 14 rotates and descends to insert the sample into the ultrasonic container 16 for ultrasonication, and then measurement is performed.

[0063] The continuity of the circuit is achieved by the platinum disk electrode being conducted through copper wire to the bushing, then through the contact to the conductive platform 19, then through the conductive spring 20 to the copper plate above the shielding box, and finally connected to the positive electrode. The reference electrode is fixedly connected to the negative electrode.

[0064] In the specific measurement process, the pre-treated glass single nanopore channel, fixed in a sample container, is placed on the sample rotation stage, and a picoammeter is connected. The industrial control screen 24 displays a program developed using QT. The program interface is divided into a left half (measurement control) and a right half (automation control). In the measurement control interface, the serial port connected to the picoammeter is selected, and parameters are set, including the starting voltage, ending voltage, step voltage, current range, scanning direction, number of cycles, and file save location. In the automation control interface, the serial port connected to the device's control chip is selected. Here, the sample stage can be manually controlled to rise, fall, turn left, turn right, and the ultrasonic switch can be activated. If automation is required, the automation mode needs to be selected, the number of automated tests needs to be set, and a table needs to be generated to record the pore size value calculated after the test and fitting. After all settings are completed, click "Start," and the device will automatically perform the following steps in sequence: preparing for measurement (sample rotation stage descends); ultrasonic degassing; after completion, the picoammeter outputs the volt-ampere characteristic curve according to the set parameters; after the measurement is completed, the sigmoid four-parameter fitting algorithm is used to fit the S-shaped function to obtain the steady-state current value, which is then calculated using the formula. Calculate the pore size value directly and output it to a table; if the current test group does not exceed the total number, switch samples; otherwise, end the process.

[0065] Aperture measurement employs a sigmoid four-parameter fitting algorithm, which boasts strong robustness and automated processing capabilities. This algorithm first performs a data quality pre-check on the read specified cyclic volt-ampere characteristic data (voltage V, current I), including checking the sufficiency of data points and the significance of current variation ranges, to filter out invalid or noise-dominated data. Subsequently, signal preprocessing is performed: an adaptive window Savitzky-Golay filter is applied to smooth the current signal, effectively suppressing high-frequency noise. Based on this, the median absolute deviation (MAD) outlier detection algorithm is used to identify and remove interference points such as impulse noise based on the residuals of the smoothed data, improving data purity. To ensure the convergence and reliability of fitting under complex data, the algorithm performs intelligent parameter initialization guided by physical constraints based on the processed data. The curve steepness is dynamically estimated according to the voltage range, and the center voltage of the platform is taken as the median voltage value. During fitting, an improved Trust Region Reflective (TRF) algorithm is used for constrained nonlinear least squares fitting. Key constraints include setting the steepness parameter k ≥ 0 to ensure physical meaning. To ensure the reliability of the fitting results, the algorithm incorporates a triple rigorous verification mechanism: calculating the coefficient of determination R² to verify the goodness of fit; requiring parameter k to ensure the curve has a clear plateau transition characteristic; and requiring the plateau current difference to confirm a significant change in conductance. After all verifications are passed, the algorithm outputs the four successful parameter values ​​(A, B, k, V0) and the R² value, where the steady-state current value typically corresponds to parameter BA for subsequent aperture calculation (A and B represent the upper and lower asymptotes of the S-curve, respectively). If any step fails, a clear error message is output. This algorithm, which integrates data preprocessing, physical constraint guidance, and multiple robust verifications, can run efficiently and stably in an automated pipeline environment, accurately extracting the plateau current and providing reliable input for aperture calculation.

[0066]

[0067] The above description is merely a preferred embodiment of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial modifications made to the present invention by those skilled in the art within the scope of the technology disclosed in the present invention using this concept shall be deemed as an infringement of the protection scope of the present invention.

Claims

1. An automated device for pretreatment and measurement of glass single-nanopore surface, characterized in that, include: Surface pretreatment equipment, measuring equipment, and a control module for controlling the operation of both, wherein, The surface pretreatment equipment includes a first sample rotation switching stage, which has a first linkage shaft and is fixed to a first Z-axis lifting stage; a container for a super oxidizing cleaning agent, a container for pure water cleaning, a container for ethanol cleaning, and a hot air drying module are arranged around the first linkage shaft at intervals; the first sample rotation switching stage rotates under the action of the first sample rotation switching stage and sequentially enters the cleaning agent container, the container for pure water cleaning, the container for ethanol cleaning, and the hot air drying module. The measuring device includes a second sample rotation switching stage and a measuring container. The second sample rotation switching stage has a second linkage shaft, which is fixed to a second Z-axis lifting platform. The second sample rotation switching stage rotates under the action of the second sample rotation switching stage and enters the measuring container. A conductive platform is provided on the second sample rotation switching stage. A reference electrode is provided inside the measuring container. The circuit connectivity is achieved by conducting the circuit from the platinum disk electrode through copper wire to the sleeve with the glass capillary tube inserted, then through contact to the conductive platform, then through the conductive spring to the copper plate above the shielding box, and finally connecting to the positive terminal of the picoammeter. The reference electrode is fixedly connected to the negative terminal of the picoammeter. The first and second sample rotation switching stages have identical structures, each including a slider, belt, drive wheel, driven wheel, guide post, fixed plate, and two motors. The fixed plate is mounted on a second base, with a horizontally extending section at its upper end. A guide post is vertically positioned between the horizontal section and the base, with its upper end passing through the horizontal section. A slider is fitted into the middle of the guide post. Rotation of the guide post drives the slider to move up and down. A motor is fixed on the slider, and its output shaft is linked to the linkage shaft of the sample rotation switching stage, so that rotation of the motor's output shaft drives rotation of the first linkage shaft. The upper end of the guide post is fixed to the driven wheel, and a drive wheel is located beside the driven wheel, with a belt connecting the drive wheel and the driven wheel. The drive wheel is linked to the output shaft of the other motor.

2. The automated equipment for pretreatment and measurement of glass single-nanopore surface according to claim 1, characterized in that, The first rotary switching stage and / or the second sample rotary switching stage are provided with multiple sample insertion holes around the edge in a circumferential direction for inserting sleeves containing glass capillaries.

3. The automated equipment for pretreatment and measurement of glass single-nanopore surface according to claim 1, characterized in that, The pure water cleaning container is equipped with an ultrasonic transducer, which is connected to the bottom of a first peristaltic pump. The first peristaltic pump is connected to a first solenoid valve. The first solenoid valve is a three-way valve, with one end connected to water, one end connected to the pure water cleaning container, and the other end discharging waste liquid.

4. The automated equipment for pretreatment and measurement of glass single-nanopore surface according to claim 1, characterized in that, The ethanol cleaning container is equipped with an ultrasonic transducer, and its bottom is connected to a second peristaltic pump. The second peristaltic pump is connected to a second solenoid valve. The second solenoid valve is a three-way valve, with one end connected to ethanol, one end connected to the ethanol cleaning container, and the other end discharging waste liquid.

5. The device according to claim 1, characterized in that, The conductive platform overlaps with the second sample rotary switching stage.

6. The device according to claim 1, characterized in that, The second sample rotary switching stage has a spring at the top center. The spring contacts and conducts electricity with the conductive platform. The conductive platform contacts and conducts electricity with the metal sleeve containing the sample. The metal sleeve conducts electricity with the tip of the platinum wire through a copper rod that clamps and welds the platinum wire.

7. The device according to claim 1, characterized in that, The measuring container is located inside the ultrasonic container, and the bottom of the ultrasonic container is equipped with an ultrasonic transducer.

8. The device according to claim 1, characterized in that, The fixed plate has a guide rail on its side, and the extension of the slider has a guide part corresponding to the guide rail on the side facing the fixed plate.

9. An automated method for pretreatment and measurement of glass single-nanopore surface, using the equipment described in any one of claims 1 to 8, comprising the following steps: Step S1: Fix the polished glass single nanopore channel with a metal sleeve and place it on the first sample rotation switching stage. Fill the container with piranha solution in the super oxidizing cleaning agent container; fill the pure water cleaning container and the ethanol cleaning container with pure water and ethanol, respectively; firstly, the first sample rotation switching stage descends to immerse the glass single nanopore channel in the piranha solution at high temperature, then rises, rotates, and descends to allow the glass single nanopore channel to enter the pure water cleaning container for pure water cleaning; then rises, rotates, and descends again to allow the glass single nanopore channel to enter the ethanol cleaning container for ethanol cleaning; finally, rises, rotates, and descends to enter the hot air drying module for drying, and after completion, rises, rotates, and returns to its original position; In step S2, the sample that has undergone surface pretreatment in step S1 is inserted into the socket of the second sample rotary switching stage. The second sample rotary switching stage rotates and descends to insert the sample into an ultrasonic container containing electrolyte for ultrasonication, and then measurement is performed.

10. The automated method for pretreatment and measurement of glass single-nanopore surface according to claim 9, characterized in that, In step S2, an external picoammeter is connected to the automated aperture measurement equipment.

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