Problem: There are different ways to clean vials. The most popular one is by dipping the vessels into a highly purified acid. Also, after the cleaning, rinsing is done with DI water but most of the time drying is done with conventional air available in the lab, which again could bring contamination.

Thus, at the end of this process which requires up to a week, the vessel is still not perfectly clean, resulting in blanks not low enough, and a significantly high amount of money is spent to get the high purity level acid. In addition to that, disposing of the contaminated acid after the cleaning could be a significant cost.

There are other conventional methods available to clean vessels (dish machines, etc.) but none of them bring a significant improvement in terms of purity, cost, and lead time savings.

Solution: One way to handle all the issues operators face with conventional methods is the ETC (EasyTraceCleaner), which features the following benefits:

• Operates with analysis grade acid
• No additional cost for acid disposal after processing
• Acid can be recycled
• Low volume of acid is required (total solution is about 15-20 fl oz or half a liter)
• Short lead time (about half a day)
• 24/7 service life

The ETC operates in close atmosphere, thus, there is no risk of outside contamination. First, an acid solution (10 to 25% concentration, depending on the trace elements which should be removed) is introduced into the equipment. Then, purified acid vapor is generated and penetrates into the container by convection. All the surface area including micro-cracks is in contact with the acid vapor. This is a great difference and a significant advantage versus the dipping process which does not offer such an efficiency. Then, as the acid vapor condenses on the inner wall of the containers, it dissolves any contaminants present on this wall and into the micro-cracks, wherever they are located. The droplets containing these contaminants are returned to the tray by gravity.

Any contamination extracted this way is then trapped and insulated in the acid bath. This operation is continuously repeated during the cleaning step, the acid vapor being continuously re-purified without contamination. Then, DI water is introduced and steam DI water is generated to rinse the vessel. The last step is to eliminate steam water without introducing air from the outside, preventing any outside contamination. Matching requested temperature levels and gradients are very important to perform this operation. Equilibrium temperature is a key factor to succeed and the ETC system is designed to reach it, whichever acid and vials are used.

This equipment can also automatically operate by adding a CRD. In this case, the temperature controller manages the different steps (cleaning, rinsing, and drying). The ETC will automatically pick up from the recipients the required quantity of both water and acid. In case there is no need to keep the acid for further cleaning, both contaminated acid and water are rejected into a third bottle.

For more information, visit www.analab.fr