The cleaning of chromatography sample vial is a very important thing in the laboratory. If the cleaning is not thorough, it may affect the next measurement. The director masters the cleaning of chromatography sample bottles is a skill that every laboratory must have. The following explains to you how to clean several chromatography sample bottles.
With the improvement of the quality of life, countries all over the world pay more and more attention to food quality and safety, and the technology of chromatographic analysis is also quickly applied to food and quality and safety testing, especially in the fields of agricultural products and pharmaceutical products. Technology has been widely used.
Every year, there are a large number of agricultural products, and pharmaceutical products are tested by liquid chromatography and meteorological chromatography. Because of the huge number of samples tested, there will be a lot of chromatographic injection bottles that need to be cleaned during the batch test. Not only will the test time be wasted, but also the cleaning of chromatographic sample bottles will affect the detection result. Therefore, the cleaning of chromatographic sample bottles is a very important thing, according to the conventional glass instrument washing method, select the cleaning method according to the degree of contamination of the chromatographic sample bottle.
Compared with many laboratory precision analytical instruments, the sample vial is very small but very commonly used. It is very important to select and use the sample vial correctly. When choosing the correct vial for your application, you need to consider three factors: the septum, the lid, and the vial itself.
1. Gasket PTFE/silicone It is recommended for multiple injections and sample storage. It has resealing characteristics. It has the chemical resistance of PTFE before piercing, and the septum will have chemical compatibility with silicone after piercing.
PTFE/silica gel (pre-cut) Provide good ventilation to prevent the formation of a vacuum in the sample vial, thus achieving excellent sampling reproducibility. It eliminates the clogging of the bottom needle after sampling and has a good resealing ability. It is recommended for multiple injections.
2. Bottle Cap Screw cap The universal bottle cap has a good sealing effect. It can bear the septum mechanically without additional tools.
Jaw cover Aluminum jaws, a good sealing effect, to prevent sample evaporation. High-temperature experimental environment, more resistant to high temperature. Need to use with a capping device.
Bayonet cover The sealing effect of the bayonet cover is not as good as the screw cover and jaw cover. The push-type bayonet cover is ideal for storing powder samples, not for transporting liquids. If the fit of the cap is very tight, the cap is difficult to close and may break; if it is too loose, the sealing effect will be poor.
3. Bottle Type I, 33-expanded borosilicate glass It is a very chemically inert glass, usually used in analytical laboratories, to obtain high-quality experimental results. Its expansion coefficient is about 33×10^(-7) ℃, mainly composed of silicon oxide, and also contains trace amounts of boron and sodium. All Waters clear glass sample bottles are Type I 33-expanded glass.
Type I, 51-expanded glass Its expansion coefficient is about 51x 10^(-7) ℃, mainly composed of silicon and oxygen, and also contains trace amounts of boron.
Deactivated glass (DV) For analytes that have strong polarity and can bind to the polar glass surface of the glass, deactivated vials may be a good choice. The glass sample vial is treated with a glass-phase reactive organosilane to produce a hydrophobic glass surface. Deactivated vials can be stored dry indefinitely.
Polypropylene plastic Polypropylene (PP) is a non-reactive plastic that can be used where glass is not suitable. Polypropylene vials can still maintain a good seal when fired, thereby greatly reducing the possibility of exposure to potentially hazardous substances. High use temperature is 135 ℃.