Please make your own choice based on the situation of your own laboratory.
It is important to find an effective way to clean the sample vials
At present, there are a large number of agricultural products samples (other chemical products, organic acids, etc.) that need to be tested by liquid chromatography and gas chromatography every year. Due to the large number of samples, there are a large number of sample vials that need to be cleaned during the detection process, which not only wastes time and reduces work efficiency, but also sometimes causes deviations in the experimental results due to the cleanliness of the cleaned sample vials.
The chromatographic sample vials is mainly made of glass, seldom is made of plastic. Disposable sample vials are expensive, wasteful, and pollute the environment. Many laboratories clean the sample vials and reuse them.
At present, the commonly used laboratory methods wash vials are mainly added detergent, detergent, organic solvents and acid wash, and then fixed brushing small tube system.
This conventional scrubbing method has many disadvantages:
The use of detergent consume water a lot, the washing time is long, and there are corners hardly to clean. If it is a plastic sample vials, it is easy to have brush marks inside the vials wall, which takes up a lot of labor resources. For glassware that is heavily polluted by lipid and protein residues, alkaline lysis solution is used for cleaning, and good results are achieved.
When analyzing samples by LC/MS/MS, the cleaning of the injection vials is very important. According to the cleaning method of glassware, the cleaning method is selected according to the degree of pollution. There is no fixed mode. Method summary:
Option One:
1. Pour the test solution in the dry vials
2. Dip all the test solution in 95% alcohol, wash it twice with ultrasonic and pour it out, because the alcohol easily enters the 1.5mL vial and can be miscible with most organic solvents to achieve the cleaning effect.
3. Pour in clean water, and ultrasonically wash twice.
4. Pour the lotion in the dry vials and bake at 110 degrees Celsius for 1 to 2 hours. Never bake at high temperature.
5. Cool and save.
Option two:
1. Rinse with tap water several times
2. Put it into a beaker filled with pure water (Millipore pure water machine) and sonicate for 15 minutes
3. Change the water and ultrasound for 15 minutes
4. Soak in a beaker filled with absolute ethanol (Sinopharm Group, Analytical Pure)
5. Finally, take it out and let it air dry.
Option three:
1. First soak in methanol (chromatographically pure), and ultrasonically clean for 20 minutes, then pour the methanol dry.
2. Fill the sample vials with water, and ultrasonically clean for 20 minutes, pour the water .
3. Dry the sample vials afterwards.
Option Four:
The washing method of the sample vials is the same as the preparation of the liquid phase, etc. First, use medical alcohol to soak for more than 4 hours, then ultrasound for half an hour, then pour out the medical alcohol, and use water for half of ultrasound. Hours, rinse with water and dry it.
Option five:
First, soak in a strong oxidizing cleaning solution (potassium dichromate) for 24 hours, and then use deionized water in ultrasonic Wash it three times under the conditions, and finally wash it with methanol once, and then dry it for use.
The caps septas must be replaced, especially when analyzing pesticide residues, otherwise it will affect the quantitative results.
But if conditions permit, try to use disposable consumables, such as disposable PTFE inserts or domestic plastic inserts (about 0.1 yuan/piece), and sample vials are fine. Repeated use and do not need to be cleaned.
Option six:
(1) complicate cleaning process with practical results:
No1. After the sample vials is used, rinse the sample vials with running water first, and rinse off the remaining sample (you can shake it by hand at the same time);
No2, then put the sample vials into the potassium dichromate washing liquid bubble, and when it accumulates When you reach a certain amount or when you are in a good mood, take it out of the lotion tank and put it in a plastic sieve for kitchen use. Rinse thoroughly with tap water. You can repeatedly sieve and shake in the middle;
No3. Use tap water to ultrasonically clean 3 times after rinsing. Around, it is best to shake out the water in the sample vials after each ultrasonic cleaning;
No4, then use triple distilled water (or purified water, deionized water) with 1.3 ultrasonic cleaning three times;
No5, then use chromatographic pure methanol ultrasonic cleaning 2-3 times, it is also best to
shake the methanol out of the sample vials after each cleaning;
No6. Put the sample vials in the oven and dry it at about 80 degrees, and it can be used.
(2) sample vials purchased to mark with different colors:
if you’ve noticed that there is a small colored mark on the sample vials, which is not for good looks, but has its use. When buying, it is best to buy several vials of different colors.
For example: your laboratory opens two projects A and B at the same time. The first time A project uses a white sample vials, and the B project uses a blue sample vials. After the test is completed, it is cleaned according to the above method, and the second experiment At the time, use blue sample vials for A project, white sample vials for B project, and so on, which can effectively avoid the trouble caused by pollution to your work.
Write at the end
1. Several instrument engineers have suggested: Use a muffle furnace at 400 degrees to bake for half an hour, the organic things are basically gone;
2. Put the sample vials into the muffle furnace for drying at 300 degrees Celsius. An Agilent engineer from Beijing said when he came to the muffle furnace, the test will be no noise after baking in the muffle furnace at 300 degrees for 6 hours.
also………..
Small volumetric flasks, pear-shaped flasks for rotary evaporation, and other glassware for analysis or pretreatment can be cleaned by referring to this method.
Post time: Feb-25-2022