Guidelines for the use of procalcitonin assay kits

The usage guidelines for procalcitonin (PCT) assay kits usually depend on the specific type of kit and detection method. However, different brands of reagent kits may differ in details, but generally follow similar steps. The following is a general usage guide for a procalcitonin assay kit based on immunofluorescence chromatography (a common PCT detection method):

1、 Kit composition

Typically, the procalcitonin assay kit (immunofluorescence chromatography) consists of the following main components:

Test card: includes reagent strips, plastic boxes, etc., on which specific antibodies are wrapped to capture PCT.

Buffer solution: used to dilute the sample and ensure the smooth progress of the detection process.

ID chip (optional): Contains basic project information, batch information, and calibration curves, used for calibration and interpretation of test results.

2、 Sample preparation

Sample type: Suitable for samples such as human serum, human plasma (EDTA anticoagulation), and human whole blood (EDTA anticoagulation).

Sample collection: Collect samples according to standard procedures and isolate serum or plasma for testing as soon as possible to avoid hemolysis.

Sample storage: Samples should be transported and stored under conditions of 2 ℃ to 8 ℃. Serum/plasma samples can be stably stored at 2 ℃ to 8 ℃ for 7 days, and stored in dark at -20 ℃ for 1 month. Whole blood samples can be stably stored for 3 days at temperatures ranging from 2 ℃ to 8 ℃.

3、 Detection steps

Reagent preparation: Restore the reagent kit and sample to room temperature, and check the validity and integrity of the reagent kit.

Sample dilution (if necessary): According to the instructions of the reagent kit, mix the sample and buffer solution in a certain proportion evenly.

Sample addition: Drip the diluted sample into the sampling hole of the test card.

Reaction: Wait for the sample to undergo an immune reaction with the antibodies on the test card, forming an antigen antibody complex.

Detection: Use a matching fluorescence detector to detect the fluorescence intensity on the test card, and convert the PCT concentration based on the calibration curve.

4、 Interpretation of Results

Result report: Report the concentration of PCT in the sample based on the readings of the testing instrument. Usually, when the concentration of PCT is below 0.10ng/ml, the reported result is 0.10ng/ml; When the concentration of PCT is higher than 100.00 ng/ml, the reported result is>100.00 ng/ml.

Result explanation: Elevated PCT levels are usually associated with bacterial or invasive fungal infections, and the magnitude of the increase is positively correlated with the severity of the infection. However, about 50% of patients with bacterial pneumonia may have normal or slightly elevated PCT levels, so normal or slightly elevated PCT levels cannot rule out bacterial pneumonia.

5、 Precautions

Strictly follow the instructions: Before using the reagent kit, please read and follow the instructions carefully.

Sample processing: Ensure that the collection, separation, storage, and transportation of samples comply with regulations to avoid affecting the test results.

Quality control: Regular quality control testing is conducted to ensure the accuracy and reliability of the test results.

Storage conditions: The storage conditions of the reagent kit and sample should meet the requirements of the instructions to avoid affecting the validity period of the reagent kit and the stability of the sample.

Please note that the above guidelines are general steps for PCT assay kits based on immunofluorescence chromatography. Different brands and models of reagent kits may have different details, so please refer to the specific instructions of the reagent kit when using it in practice.