Analysis of minute amounts of blood as in Dried Blood Spots requires state of the art analytical technology with high end analytical instruments with the highest sensitivity and precision. Recent LC-MS/MS instruments fulfil these demands and allow pharmaceutical ADME/DMPK studies, biomarker studies, clinical studies and vitamins, nutraceuticals and food safety analyses using DBS. Next to analysis by LC-MS/MS the relative abundance of several compounds allows also for assessment in DBS by immuno-methodology.
LC-MS/MS technology is based on separation of compounds as drugs and their metabolites by chromatography with High Pressure Liquid Chromatography (HPLC) followed by Mass Spectrometry (MS). This methodology has revolutionized the analytical measurements in the past decades and has become the most commonly used bio-analytical method in drug development. Due to its high specificity, it differentiates the drug compound from its metabolites and other similar compounds. The tandem MS/MS technique utilizes two separate Mass Spectrometers with a (high vacuum) collision cell in between. The collision generates specific products (daughter-ions) resulting in characteristic molecular fragments (fingerprints). Highly sensitive separation of these collision products by the second MS underlies the high specificity of the technique. The high sensitivity is based on the extremely advanced ion detection techniques used. The ultra-sensitivity of the recent LC-MS/MS instruments makes quantitative measurements in small amounts of blood like DBS possible. LC-MS/MS instrumentation requires highly trained experts to appropriately operate and maintain these complex analytical systems.