The stability and reliability of the SPE are of vital importance for the experimental results

**Author:Orgianl from Internet

Solid-phase extraction technology is a separation and purification method that uses adsorbents to extract the target substances from complex matrices. Currently, solid-phase extraction has been widely applied in fields such as environment, food, and biology. The solid-phase extraction instrument is one of the core devices for implementing this technology, and its stability and reliability are crucial for the experimental results.

However, during long-term use, due to human operational errors or equipment-related reasons, various faults may occur in the solid-phase extraction instrument. This article will introduce several common types of faults and their solutions based on practical experience.

When the manual injection key is pressed, the injection needle cannot move downward; there is no response even in the automatic mode.

(1) The power plug is not firmly inserted;

(2) The main control board is not properly connected to the stepper motor;

(3) The stepper motor is damaged;

(4) The mechanical components are stuck or clogged.

(1) Check if the power plug is properly connected;

(2) Check if the connection between the main control board and the stepper motor is good;

(3) Replace the stepper motor;

(4) Inspect the mechanical components, such as the three-way valve, etc., to see if they are stuck or clogged.

When the solid-phase extraction instrument was turned on, the pump failed to operate normally.

(1) The power plug was not firmly inserted.

(2) The pump pipe was damaged or fell off due to being hit by gas or liquid.

(3) The failure of key components caused the pump to malfunction.

(1) Ensure that the power plug is securely connected to the device;

(2) Inspect and replace any pump tubes that may be damaged or loose;

(3) If neither of the above situations exist, the device needs to be disassembled for detailed troubleshooting and the key components need to be identified for relevant repairs.

When using the solid-phase extraction instrument to extract the target substance, the sample volume should be 1000 uL. However, the actual extraction result shows that there is almost no target substance (too small), or the obtained solution is significantly concentrated (too large).

(1) The sample injection volume was set incorrectly;

(2) The extraction column was used for too long or got clogged;

(3) The flow rate adjustment of the solid-phase extraction instrument was improper.

(1) Check and re-adjust the sample injection volume;

(2) Replace the solid-phase extraction column and ensure its normal operation;

(3) Adjust the liquid flow rate and pressure in the solid-phase extraction instrument according to the experimental requirements to obtain the correct sampling volume.

When extracting the target substance, the obtained solution contains a large number of non-target compounds, resulting in a relatively low quality of the results.

(1) Choosing the wrong type or specification of adsorbent;

(2) Failure to properly pre-treat the analyte matrix, resulting in the presence of interfering substances;

(3) Operational mistakes in simple steps leading to incorrect execution.

(1) Confirm whether the adsorbent is selected appropriately and has been verified for feasibility before starting the operation. For example, this can be determined through experimental comparison;

(2) Use appropriate methods to pre-treat the analyte matrix, such as pH adjustment and the addition of salts, which will have a significant impact;

(3) Carefully read the operating instructions of the solid-phase extraction instrument and follow them. If unsure, refer to relevant materials or consult professionals.

The above has introduced the common faults of the solid-phase extraction instrument and their solutions. In practical applications, we need to be patient in dealing with each problem and try to find the most appropriate and reliable solutions to ensure that the samples used for analysis and detection of the target substances have high quality and accuracy.