US Patent No. 7,422,625, titled “Methods and Systems for Characterizing a Sorbent Tube,” has been awarded to PerkinElmer Inc. of Waltham, Mass., a health and safety service provider. The new method provides gas chromatographers with more accurate results when using automated thermal desorption gas chromatography, an air monitoring system used for examining soil, water, biofuels, polymers, packaging materials and pharmaceuticals, among other applications.