Disclosure of Invention
The invention aims to: aiming at the problems existing in the prior art, the invention provides an automatic calibrating device for a high-precision pipettor. According to the device, the liquid weighing assembly and the suction head loading assembly are combined in the same device through the design of the pipette movement assembly with the horizontal and vertical two-dimensional movement capability, so that an automatic pipette verification device can be realized, verification efficiency is improved, verification errors are reduced, verification range is enlarged, and a pipette verification result is more credible.
The technical scheme is as follows: in order to achieve the above object, the invention provides an automatic calibration device for a high-precision pipette, which is characterized by comprising a pipette movement assembly, a liquid weighing assembly, a suction head storage assembly and a device base; the liquid weighing assembly and the suction head storage assembly are arranged on the device base side by side, and the pipettor movement assembly is arranged behind the liquid weighing assembly and the suction head storage assembly; the motion assembly of the liquid transfer device comprises a vertical screw rod and a horizontal screw rod, the top end of the vertical screw rod is connected with a vertical motor, the side end of the horizontal screw rod is connected with a horizontal motor, and the vertical screw rod is further provided with a sliding block for mounting the liquid transfer device to be tested; the liquid weighing assembly comprises a high-precision analytical balance, and a liquid container is arranged on the high-precision analytical balance; the tip storage assembly includes a tip cartridge holder for storing a disposable pipette tip.
The pipette movement assembly is used for fixing and driving the pipette to be measured to move, wherein the vertical motor drives the pipette to move up and down, and the horizontal motor drives the pipette to move horizontally.
The liquid weighing assembly is used for weighing the test liquid with high precision and recording the result, the high-precision analytical balance is used for weighing the liquid to be tested, and the liquid container is used for containing the liquid to be tested.
The tip storage assembly is used for storing disposable tips for pipetting.
The automatic calibrating device for the high-precision liquid transfer device is characterized in that the motion assembly of the liquid transfer device is provided with an independent vertical motion module and a horizontal motion module, so that the automatic calibrating device for the high-precision liquid transfer device has two-dimensional motion capability, and the independent liquid weighing assembly and the suction head storage assembly are combined in the same device, so that an automatic flow of calibrating the liquid transfer device is realized.
Further, an upper limit sensor and a lower limit sensor are arranged on the side edge of the vertical screw rod. The upper limit sensor and the lower limit sensor are used for limiting the up-and-down movement range of the pipettor.
Further, the top end of the liquid container is provided with an anti-evaporation trap. The evaporation prevention trap is used to prevent evaporation of the liquid.
Further, a fixing component is further arranged on the moving component of the liquid transfer device, one end of the fixing component is fixed on the high-precision analytical balance, and the other end of the fixing component is fixed on the base of the device. The fixed component is used for preventing the high-precision analytical balance from moving in the verification process of the pipettor, and the weighing operation is influenced. The fixing component is a Z-shaped iron frame, and the high-precision analysis level and the device base are respectively fixed through screws.
Further, a suction head box positioning block is arranged at the bottom of the suction head box bracket. The positioning block is used for determining the placement position of the suction head box bracket at the beginning of each pipette verification.
Further, four screws of the pipette to be measured are fixed on a sliding block of the vertical screw rod, and the sliding block is meshed with the vertical screw rod through threads.
Working principle: step 1: the device is characterized in that a to-be-measured liquid-transfering device is firstly fixed on a sliding block positioned on a vertical screw rod through four screws, the sliding block is meshed with the vertical screw rod through threads, and the sliding block can be driven to move up and down simultaneously when the vertical screw rod is driven by a vertical motor to rotate, so that the to-be-measured liquid-transfering device fixed on the sliding block is enabled to have the capability of moving in the vertical direction, wherein an upper limit sensor is used for limiting the upper limit of movement of the to-be-measured liquid-transfering device, and a lower limit sensor is used for limiting the lower limit of movement of the to-be-measured liquid-transfering device
Step 2: after the to-be-tested pipettor is installed, the device drives the horizontal screw rod to rotate through the horizontal motor to enable the to-be-tested pipettor to horizontally move, the to-be-tested pipettor firstly horizontally moves to a fixed position above the suction head box support and then vertically moves downwards until the to-be-tested pipettor successfully loads the disposable pipette tips stored on the suction head box support, wherein the positioning block is used for determining the placement position of the suction head box support at the beginning of each pipette verification;
step 3: after the disposable pipette tip is loaded, the device drives the pipette tip to be measured to horizontally move to a fixed position above the high-precision analytical balance, then the pipette tip to be measured vertically moves downwards, so that the disposable pipette tip enters a liquid container containing test liquid and absorbs the test liquid, after the suction is completed, the pipette tip to be measured vertically moves upwards to an initial position, the high-precision analytical balance performs peeling operation, after the peeling operation is completed, the pipette tip to be measured vertically moves downwards again to the liquid container to release the test liquid, and moves upwards to return to the initial position again, the high-precision analytical balance performs weighing operation on the released test liquid and records the weight of the test liquid, an evaporation prevention well is used for preventing the test liquid in the liquid container from evaporating to influence weighing, and a fixed component is used for preventing the high-precision analytical balance from moving in the verification process of the pipette to influence weighing operation.
Step 4: the pipette to be measured moves horizontally to a designated position, and the disposable pipette tip is unloaded.
Step 1-4 is a complete pipetting weighing process, multiple groups of pipetting weighing data can be obtained by repeating step 2-4, statistical analysis is performed, pipetting accuracy of the pipettor (2) to be detected is calculated, and whether the pipettor meets relevant national (international) standards is verified.
The beneficial effects are that: compared with the prior art, the invention has the following advantages:
according to the invention, through the combined use of the pipette movement assembly, the liquid weighing assembly and the suction head storage assembly, the pipetting operation and the weighing operation in the pipette verification process are combined in the same device, and the automatic process of pipette verification is realized. The device has the horizontal movement capability, so that the liquid weighing assembly and the suction head storage assembly can be simultaneously placed on the device for combined use, and the automation degree of the device is improved; the vertical movement capability enables the to-be-detected pipettor which does not have the up-and-down movement capability to realize automatic verification of the pipettor in the designed automatic device, so that the verification range of the pipettor is enlarged, and the verification capability of the device is improved.
Detailed Description
The invention is further described below with reference to examples and figures.
Examples
As shown in fig. 1-4, a high-precision automatic calibration device for pipettes comprises a pipettor movement assembly 1, a liquid weighing assembly 2, a suction head storage assembly 3 and a device base 4; the liquid weighing assembly 2 and the suction head storage assembly 3 are arranged on the device base 4 side by side, and the pipette movement assembly 1 is arranged behind the liquid weighing assembly 2 and the suction head storage assembly 3.
The pipette motion assembly 1 comprises a vertical screw rod 5 and a horizontal screw rod 6, the top end of the vertical screw rod 5 is connected with a vertical motor 7, the side end of the horizontal screw rod 6 is connected with a horizontal motor 8, a sliding block 10 for installing a pipette 9 to be measured is further arranged on the vertical screw rod 5, the pipette 9 to be measured is fixed on the sliding block 10 of the vertical screw rod 5 through four screws, the sliding block 10 is meshed with the vertical screw rod 5 through threads, and an upper limit sensor 15-1 and a lower limit sensor 15-2 are arranged on the side edge of the vertical screw rod 5.
The liquid weighing assembly 2 comprises a high-precision analytical balance 11, a liquid container 12 is arranged on the high-precision analytical balance 11, and an anti-evaporation well 16 is arranged at the top end of the liquid container 12. The movable component 1 of the liquid transfer device is prevented from moving by arranging a fixing component 17, the fixing component 17 is a Z-shaped iron frame and is fixed on the high-precision analytical balance 11 through one end of a screw, and the other end of the fixing component is fixed on the device base 4.
The tip storage assembly 3 comprises a tip box bracket 14 for storing a disposable pipette tip 13, and a tip box positioning block 18 is arranged at the bottom of the tip box bracket 14.
The device firstly fixes the to-be-measured pipettor 9 on the sliding block 10 positioned on the vertical screw rod 5 through four screws, the sliding block 10 and the vertical screw rod 5 are engaged through threads, and when the vertical motor 7 drives the vertical screw rod 5 to rotate, the sliding block 10 can be simultaneously driven to move up and down, so that the to-be-measured pipettor 9 fixed on the sliding block 10 is enabled to have the capability of moving in the vertical direction, wherein the upper limit sensor 15-1 is used for limiting the upper limit of the movement of the to-be-measured pipettor, and the lower limit sensor 15-2 is used for limiting the lower limit of the movement of the to-be-measured pipettor
After the to-be-measured pipettor 9 is installed, the device drives the horizontal screw rod to rotate through the horizontal motor 8 to enable the to-be-measured pipettor 9 to horizontally move, the to-be-measured pipettor 9 firstly horizontally moves to a fixed position above the suction head box support 14 and then vertically moves downwards until the to-be-measured pipettor 9 successfully loads the disposable pipette head 13 stored on the suction head box support 14, wherein the suction head box positioning block 18 is used for determining the placement position of the suction head box support 14 at the beginning of each pipette verification;
after the disposable pipette tip 13 is loaded, the device drives the pipette 9 to be measured to horizontally move to a fixed position above the high-precision analytical balance 11, then the pipette 9 to be measured vertically moves downwards, so that the disposable pipette tip 13 enters a liquid container 12 containing test liquid and absorbs the test liquid, after the disposable pipette tip 13 is absorbed, the pipette 9 to be measured vertically moves upwards to an initial position, the high-precision analytical balance 11 performs peeling operation, after the peeling operation is finished, the pipette 9 to be measured vertically moves downwards again to the liquid container 12 to release the test liquid, and moves upwards to return to the initial position again, the high-precision analytical balance 11 performs weighing operation on the released test liquid and records the weight of the test liquid, an evaporation prevention trap 16 is used for preventing the test liquid in the liquid container from evaporating to influence weighing, and a fixed component 17 is used for preventing the high-precision analytical balance from moving in the verification process of the pipette, and the weighing operation is influenced.
The pipette 9 to be measured moves horizontally to the rightmost end of the verification device, and the disposable pipette tip 13 is unloaded, so that a complete pipetting and weighing process is completed. And (3) repeating all the steps to obtain a plurality of groups of pipetting weighing data, carrying out statistical analysis, calculating pipetting accuracy of the pipettes 9 to be detected, and verifying whether the pipetting accuracy meets the relevant national (international) standard, namely JJG 646-2006 pipettes verification rules and ISO 8655International Standard.