The forward pipetting method, as the name suggests, refers to the operation of a pipette to draw liquid forward from the source (that is, toward the direction of the pipette tip) and expel it when necessary. This method is particularly suitable for pipetting conventional liquids, such as aqueous solutions, buffers, etc. By following certain operating steps and precautions, the forward pipetting method can ensure the accuracy and reliability of pipetting, providing a strong guarantee for the success of the experiment.
1. Operation steps of forward pipetting method 1. Range setting: Hold the pipette vertically and ensure that the capacity of the pipette is clearly visible in the digital display window on the handle. Set the pipette volume to the desired volume by turning the operating button. Clockwise rotation decreases the capacity, and counterclockwise rotation increases the capacity. 2. Liquid aspiration: Install the tip suitable for the pipette range onto the pipette, and use the rotational installation method to ensure that the tip and pipette are tightly coupled without gaps. Place the pipette vertically in your hand, keep the tip vertical, and tilt the pipette at a maximum angle of no more than 20° to avoid increasing pipetting errors. Immerse the suction tip into the liquid to be sucked, the depth is generally 2~3 mm (or adjusted according to the properties of the liquid). Press the pipette button to the first stop, then release the button smoothly to allow the liquid to be sucked into the tip. Pay attention to the uniform aspiration speed to avoid the formation of whirlpools or bubbles too quickly. 3. Liquid discharge: Take the suction head out of the liquid and slide it along the container wall to avoid liquid splashing. Transfer the tip to the receiving container, and the mouth of the tip should be close to the bottom of the inner wall of the container. First press the discharge button to the first stop point, pause briefly, and then press it to the second stop point to completely drain the liquid in the tip. 4. Tip handling: After completing the discharge, release the button to return the pipette to the origin. Keeping the button in the first stop position, carefully remove the tip with residual liquid and discard it.
2. Precautions 1. Use of pipette: Before using the pipette, ensure that the pipette has been calibrated to ensure the accuracy of pipetting. Avoid using pipettes to absorb highly volatile and corrosive liquids to avoid damage to the pipette. 2. Tip selection: Choose a tip suitable for the pipette range to ensure good sealing and pipetting accuracy. Avoid using broken or deformed tips as they may affect the pipetting effect. 3. Operating specifications: When sucking and discharging liquids, keep the pipette in a vertical position to avoid tilting causing pipetting errors. Operate the pipette buttons smoothly and avoid releasing or pressing the button suddenly, causing liquid to spill or aspirate too quickly. 4. Maintenance: After using the pipette, hang it vertically on the pipette stand and avoid laying it flat or upside down to prevent the liquid from flowing back and corroding the piston spring. Clean and calibrate your pipette regularly to keep it in good working order.
3. Disadvantages of the forward pipetting method 1. It is not suitable for pipetting liquids with high viscosity: For liquids with high viscosity, the forward pipetting method may not be able to effectively suck them into the tip, or it may leave a residue during discharge. Remove more residual liquid. 2. Volatile liquids are easy to lose: When pipetting highly volatile liquids, due to possible volatilization during the pipetting process, the liquid volume may be lost, thus affecting the accuracy of pipetting. 3. Cross-contamination is prone to occur: If sterile operating procedures are not strictly followed during the pipetting process, or unsterile tips are used, the forward pipetting method may lead to cross-contamination between different liquids. 4. Wrong usage habits affect accuracy: If the user does not correctly master the operating steps of the forward pipetting method, or has bad habits during use (such as suddenly releasing or pressing the button), the accuracy of pipetting may be affected. , and may even cause problems such as internal corrosion of the pipette.
The key to ensuring the accuracy and reliability of pipetting lies in the accurate setting of the volume, the smooth suction and discharge of liquids, and the appropriate selection and timely replacement of pipette tips. In addition, regular cleaning and calibration of pipettes are indispensable steps to maintain good performance. Although the forward pipetting method has many advantages, in actual operation, flexible selection and application still need to be made based on factors such as the characteristics of the liquid and the specific needs of the experiment. This article is intended to help you gain a deeper understanding and mastery of the forward pipetting method, and hopes to provide solid support for your experimental work.
Related reading recommendations
Quick Start Guide: Opentrons Flex Staging Area Slot
Adapter magnet support article
Micropipette verification procedures
The experienced service team and strong production support team provide customers with worry-free order services.
