Analysing unknown-unknowns, micro-molar concentrations or low abundance sample quantities 

When working with unknown-unknowns, micro-molar concentrations or low abundance sample quantities (where the surface-to-volume effects become more significant) or where pH changes can cause significant changes in analytical results, the use of RSA™ (Reduced Surface Activity) glass vials from MicroSolv Technologies, Inc can be especially beneficial.

MicroSolv’s Reduced Surface Activity (RSA) or low adsorbing autosampler vials are specially formulated and processed to yield a surface that exhibits extremely low levels of adsorption of basic, polar compounds and shows exceptional consistency of adsorption levels from vial to vial. These adsorption properties are routinely tested by MicroSolv using LCMS and other analytical techniques, by measuring the degree of disappearance of polar compounds from solution over time due to ionic interactions with the glass surface. MicroSolv have demonstrated that ordinary (non-RSA glass) vials adsorb far greater levels of these basic, polar compounds and also tend to exhibit greater variation of adsorption capacity from vial to vial (thereby worsening the RSD of any analytical measurements).

Furthermore, when a liquid sample is placed into an ordinary (non-RSA glass) autosampler vial (even for higher performing 'certified' vials) the glass can contribute to an increase in pH of the sample diluents, which can cause a host of other problems. pH shifts for ordinary glass vials of  > 1.2 pH units have been seen, whereas for  RSA glass vials the pH shift typically measures < 0.1 pH unit, with water as the sample diluent. MicroSolv regularly monitors the pH stability of RSA glass vials and the levels of sodium, boron and other elements, that can traditionally leach from the glass into the sample, are also routinely QC tested by HPLC-UV, LCMS, ICP and other analytical techniques.

The unique characteristics of MicroSolv’s low adsorbing or Reduced Surface Activity (RSA) glass vials are achieved using a proprietary manufacturing process, avoiding the use of coatings or other surface treatments that may potentially contaminate the sample and interfere with analysis.

For further information on RSA glass vials please contact Hichrom Limited, tel: +44(0)118 930 3660 or click here.