Abstract: The invention relates to a packing material for a micro-adsorption column for drying and/or purification of dissolved organic or biological analytes, such as toxins, antibiotics, vitamins, hormones, pesticides and similar, containing at least one drying agent which contains magnesium sulphate and at least one further drying agent selected from the group comprising aluminium oxide, calcium chloride, calcium hydride, calcium oxide, calcium sulphate, potassium hydride, silica gel, copper sulphate, magnesium oxide, magnesium perchlorate, molecular sieves, sodium hydroxide, phosphorus pentoxide, sulphuric acid on silica, phosphorus pentoxide on silica and 0.5 to 90 wt. % of a naturally-occurring or synthetic support with large internal surface such as zeolite, diatomic earths, bentonite, silicon dioxide or similar. The invention further relates to a micro-adsorption column packed with the above and use thereof.