Abstract: Disclosed herein are embodiments of a fixed magnet assembly that can be implemented into automated platforms for performing polynucleotide extraction from biological samples and preparing the polynucleotides into an amplification-ready form. The fixed magnet assembly can be used to provide magnetic energy to a container containing magnetic particles and a reaction mixture of polynucleotides, in order to bring about a separation of the magnetic particles from the reaction mixture. This can prevent or reduce magnetic particle carryover in the prepared amplification-ready sample, thereby improving amplification results.