Cleanert MAS is a simplified bio-sample preparation tool which offers multifunctional adsorption capabilities to remove interferences while the analytes are remained in the aqueous phase. Although protein precipitation is the most common method in bioanalysis, it is the fact that this method is not efficient for eliminating the matrix effect on LCMS/MS due to the present of phospholipids. However with Cleanert® MAS the phospholipids are effectively removed follows a similar procedures.
For amphoteric compounds, MAS-A should be followed by basic eluant (0.01%~1%NH3•H2O is suggested to be added in the elution solvent), while MAS-B should be followed by acidic eluant (0.02%-2% acetic acid is suggested to be added in the elution solvent). Because the acidity/basicity of most compounds are weaker than that of phospholipids which contain choline and phosphate group, elution of analytes and retention of phospholipids can be achieved by adjusting different pH value of the solvent.
There are two formats for Cleanert MAS
MAS cartridge: better choice for method development
MAS plate: suitable for high throughput sample analysis requirement
Product and Solvent Selection
Cleanert MAS is divided into three kinds of sorbents, named MAS-A, MAS-B and MAS-WA, which can used for neutral, acid, basic and amphoteric compounds respectively. Three kinds of products can be chosen according to the chart below. In some cases, mixing 10% methanol with the eluant may improve the efficiency of protein precipitation. 9:1~1:1 is general ratio for ACN to methanol. Proper amount of water could be mixed with the eluant for the drugs with high polarity; however, the volume ratio should not be over 1/3 to make sufficient protein precipitation. Eluant mixed with a weak reagent (acetic ether, dichloromethane etc.) is suitable for sample with low polarity.