Can the reference substance after opening the use be used in the future?
In theory, the official reference requirements are one-time use, but different comparisons, different treatments, storage conditions and use time after opening are limited.
Whether it is suitable for reuse after opening, it is necessary to look at the uniformity and stability of the reference substance. After observation and identification, the reference product is uniform and the stability remains unchanged. Then the general validity period is longer, and the shelf life of common reference materials is 3 months-1. About a year.
How to extend the shelf life of the reference?
Extending the shelf life of the reference product begins with two aspects, and the correct use and storage of the reference product can better avoid affecting the quality of the reference product.
First, the correct use of the reference
1. Open correctly
Most of the reference materials are stored in glass ampoules. Generally, when the ampoules are turned on, they can be lightly knocked, and the contents should be sunk as far as possible. When cutting, the ampules should be placed flat or downward, and the thumb of both hands should be placed against the neck. Avoid mixing glass shards into the control.
2. Seal after use
Generally, the reference substance needs to be sealed after use, and it is sealed under different environments according to the difference of the reference substance. For the reference substance which is easy to absorb moisture, such as omeprazole, if it is used for content determination, it should be used immediately after opening, and the remaining Some may be used for identification later, but it is not recommended for content determination.
3. Placed separately after expiration
For expired standards and controls, if you want to continue to save, you need to place them separately to avoid confusion. If necessary, it can also be used in an emergency and can be used for identification. If used for quantification, a traceability verification data guarantee is required.
The storage conditions of the reference solution are generally stored in a refrigerator at 2 to 8 ° C, and the interval time can be determined according to the specific characteristics of the reference solution.
Second, qualified storage reference
Common reference materials are generally selected at room temperature 2-8 degrees Celsius, stored at low temperatures, but the general control should be properly stored according to the conditions specified in the instructions, such as vitamin E, such as vitamin E, should be stored in the dark, easy to volatilize after exposure Unstable.
Pay attention to the use period of the reference product, and the expired and deteriorated reference product should not be used again. After opening the bottle, it is recommended to use it in a short period of time to avoid long-term use after opening the bottle. At the same time, it should try to avoid decomposition, pollution or moisture absorption of the reference substance during repeated use.
