The AptoPrep™ Aptoprecipitation (aptamer-based protein precipitation) kit can isolate/elute a particular protein from a sample containing several thousands of different proteins. The complete kit consists of remade aptamer-coupled magnetic beads and buffers. Its high specificity can reduce background caused by nonspecific binding. Aptamer recognizes the native form of target proteins (not the denatured form) and does not interfere with downstream mass analysis.