Micropump is a precision instrument commonly used in laboratories to inject liquids or gases into samples at precise flow rates. It is widely used in fields such as biology, chemistry, and pharmacy. Its application scenarios include but are not limited to liquid analysis, drug delivery, chemical reaction control, etc. The following provides a detailed introduction to the usage techniques of microinjection pumps:
1. Basic principle of microinjection pump
Micro injection pumps achieve precise injection of liquids or gases by precisely controlling the injection flow rate. It usually consists of the following parts:
Drive system: The injection needle or syringe is driven by a motor or stepper motor to inject liquid at a precise flow rate.
Control system: used to set and control flow rate, injection volume, and injection time to ensure the accuracy of injection.
Syringe or needle: used to hold sample liquid and push the liquid out of the syringe through a precise driving device.
Flow sensor: Some advanced infusion pumps are equipped with flow sensors for real-time monitoring of flow, ensuring the accuracy of pumping.
2. Selection of microinjection pump
When choosing a suitable microinjection pump, consider the following aspects:
Flow range: The flow rate of a microinjection pump is usually in the range of microliters (μ L) to milliliters (mL), and some devices can be precise to nanoliters (nL). It is necessary to select a pump with a suitable flow range based on the liquid volume and accuracy requirements of the experiment.
Accuracy and stability: Choose injection pumps with high accuracy and good stability, especially for experiments that require long-term precise delivery.
Control method: Currently, most microinjection pumps are digitally controlled and support operation through touch screens, buttons, or computer programs.
Types of pumps: mainly divided into:
Syringe pump: Using a standard syringe as the container, the liquid flow is controlled by an electric push rod.
Peristaltic pump: suitable for fluid transportation that requires high precision, especially for liquids that are not allowed to come into contact.
Positive displacement pump: suitable for handling liquids with high flow rates.
3. Instructions for using a microinjection pump
(1) Preparation work
Choose the appropriate syringe: Select a syringe with the appropriate capacity and specifications according to the experimental requirements. The material of the syringe (such as glass, plastic) should be selected based on the characteristics of the liquid.
Check the cleanliness of the pump: Ensure that the needle and syringe of the infusion pump are clean and free from any sources of contamination.
Set pump parameters: Set injection speed (flow rate), total injection volume, injection time, etc. according to experimental requirements.
(2) Operation steps
Installation of syringe: Install the selected syringe correctly onto the injection seat of the syringe pump, ensuring a tight connection between the syringe and pump to avoid leakage.
Set injection parameters:
Flow rate: Set the required flow rate, usually in μ L/h (microliters per hour) or mL/min (milliliters per minute).
Injection volume: Set the total injection volume to ensure that the amount of liquid pumped meets the experimental requirements.
Injection time: If necessary, the length of injection time can be set.
Start injection: Check if the equipment is running smoothly, and then start the pump. Observe whether the liquid is evenly injected to ensure there are no bubbles or leaks.
Monitoring operation: During the experiment, real-time monitoring of parameters such as flow rate and pressure of the infusion pump is carried out to ensure accurate injection of liquid at the set flow rate.
After injection: Turn off the pump and clean the equipment and syringe as needed.
(3) Adjustment and maintenance
Calibration pump: Regularly check the accuracy of the pump and calibrate the flow rate and injection volume according to experimental requirements.
Check the pumping pressure: Maintain an appropriate pressure during pumping to prevent excessive pressure from affecting the experimental results.
Liquid compatibility: Ensure that the liquid used is compatible with the material of the syringe and pump, avoiding chemical reactions or damage to the pump.
4. Application of microinjection pump
(1) Biomedical research
In cell culture, drug delivery, and microfluidic chip experiments, microinjection pumps can be used to precisely control the delivery of drugs or nutrients, ensuring the accuracy of cell experiments.
In drug delivery research, precise control of drug dosage is achieved through microinjection pumps, simulating the actual administration process, and studying drug efficacy and response.
(2) Chemical reaction control
In chemical experiments, microinjection pumps can accurately control the flow rate of reactants, helping researchers control reaction rates and study the kinetic characteristics of reactions.
Micro injection pumps also play an important role in catalyst testing and high-performance liquid chromatography (HPLC).
(3) Food and Beverage Industry
Used for precise control of the amount of additives, seasonings, and other liquids added in food processing, ensuring the accuracy and consistency of food formulas.
In the processing and analysis of trace liquids, microinjection pumps can provide high-precision delivery and are suitable for production lines that require high precision.
(4) Environmental monitoring and control
Micro injection pumps can be used in fields such as water quality analysis and gas analysis to accurately inject reagents and ensure the accuracy of analysis results.
In gas concentration monitoring, micro injection pumps can accurately control gas flow, helping laboratories to accurately analyze reactions or changes at different concentrations.
5. Common faults and their solutions
Unstable liquid flow rate: may be caused by bubbles, residual liquid in the pump, or poor sealing of the syringe. At this point, it is necessary to check whether there are bubbles in the liquid and ensure that the connection is leak free.
Flow rate too fast or too slow: Check the pump settings, confirm if they are correct, and clean the pump piping.
Syringe blockage: Clean the syringe to ensure smooth liquid flow and check for solid particle blockage.
summary
The microinjection pump can meet the high requirements for fluid delivery in experiments through high-precision control. Reasonable selection of pump specifications, setting appropriate operating parameters, and regular maintenance during use can ensure the accuracy of experiments and the longevity of equipment.