Five Most Common Cleaning Methods of The Sample Vials
With the increasing of attention to food quality and safety from all aspect of society, chromatographic analysis technology is increasingly used in the detection of food quality and safety. Chromatographic analysis technology has been widely used in the field of agricultural product testing.
Completely cleaning of chromatography sample vial is very important. The measurement may be affected if the vials are not completely clean. Hence, we must master correct cleaning methods of chromatography sample vials. Following I’d like to introduce some of them.
In China, there are a large number of samples of agricultural products (other chemical products, organic acids, etc.) need to be inspected every year through liquid chromatography and gas chromatography. There leads to a large number of chromatography sample vials need to be cleaned in the process, which not only wastes time and reduces the efficiency. Moreover, chromatographic sample vials after washing are not clean enough sometimes, which results in deviation of the experimental results.
The cleaning of chromatography vial is very important. Select the appropriate cleaning methods according to the contamination of the glass instruments. Methods are summarized as follows:
1. throw out all the sample solution in the vial
2. Dip completely in 95% alcohol and wash with ultrasonic, throw out again, as the alcohol is easy to enter the 1.5mL vial, and can be dissolved with most organic solvents.
3. Pour clear water and ultrasonic wash it twice.
4. Drain the liquid in the vials and bake it at 110 degrees Celsius for 1 to 2 hours. Baking at high temperatures is prohibited.
5. Cooling and reserve.
1. Tap water cleans several times.
2. Put in a beaker with pure water, ultrasound cleaning for 15 minutes.
3. Change the water, repeat above step.
4. Dip in anhydrous ethanol.
5. Finally pick out and natural air-dry
1. Firstly dip in methanol, then ultrasonic cleaning 20 minutes, then dry the methanol.
2. Fill the chromatographic sample vials with water, then ultrasonic cleaning 20 minutes, and pour off the water.
3. Bake the chromatography sample vials.
1. Usually wash with water firstly, dried and then soaked with potassium dichromate lotion.
2. The first step is soaking in the medical alcohol over 4 hours, then ultrasonic cleaning half hour. Pour out medical alcohol, ultrasound cleaning with water half an hour, rinse with water and bake.
1. Always use new vial if the budget is sufficient.
2. The cleaning method is very important if you want to reuse. Firstly soak in strong oxidation cleaning solution (dichromate potassium) 24 hours, then ultrasonic cleaning with deionized water three times, and finally clean with methanol once and bake.
3. Use the new mat, especially in the analyzing of pesticide residues, otherwise quantitative results will be affected.
Above are the five most common cleaning methods of the sample vials.