You use a vial from a good brand, you may use a silanized vial, but are you sure you are not losing compound, especially, when the analyte remains for a longer time in the vial (e.g. as no. 50 in the autosampler) and you work with traces? Or did you always have the feeling, that your quantification is not as accurate as it should be.
Todays vials in Europe are normally made of 1st hydrolytic class glass, according to all the different Pharmacopeias. But there are differences in the glass qualities meeting the Pharmacopeia requirement! A European 51 type glass is in specs, but for polar compounds, in ultra traces, the adsorption can be significant, up to 75% AND the value may vary from Lot to Lot or even from vial to vial! Are you willing to accept that?
If not: Thermo Scientific Chromacol GOLD GRADE vials are the solution. These vials meet every Pharmacopeia's requirements and provide a significant better low adsorption surface compared to all standard vials on the market with no surface treatment.
We are able to offer a FREE sample pack* of 6 different vials (two each) with and without micro insert for free, a meaningful white paper and a Europe wide trouble free access to all the products from the Chromacol GOLD GRADE portfolio.