Stable maintenance of the functional integrity of the microbead-conjugated plasmid during repeated synthesis reactions and long-term storage.

<p>pK7EGFP, not immobilized to microbeads, was used as a positive control (PC) and the negative control (NC) involved the cell-free protein synthesis mixture not containing DNA. (A) Magnetic microbead-conjugated plasmid (pK7EGFP) was repeatedly used for cell-free synthesis of EGFP as described in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0034429#s3" target="_blank">Materials and Methods</a> section. The size and relative amounts of the synthesized EGFP from each round of reaction were analyzed by using SDS-PAGE gel analysis with Coomassie blue staining. The arrow indicates the expected size of EGFP. (B) Magnetic microbead-conjugated plasmid (pK7EGFP) was used for cell-free synthesis of EGFP after being stored at 4°C for the indicated days. Three independent preparations of the microbead-conjugated plasmid were used in this experiment to obtain the average values and standard deviations.