Abstract
We have investigated the effects of sample-loading solutions on sequencing performance on the Applied Biosystems 3730 DNA Analyzer, and in particular their effects on the decline of sequencing performance, or loss of resolution. We compared sequencing performance of samples resuspended in water, 0.1 mM EDTA, or deionized formamide. Our results show that samples resuspended in water give poorer overall performance in terms of average number of Q20 bases per sample and in the amount of variability in Q20 scores, compared to samples in formamide or 0.1 mM EDTA. Over the course of 300 or more runs, samples in water had a significantly greater tendency towards gradual loss of resolution, while EDTA and formamide samples maintained steady high performance. We will present additional data dealing with relative advantages and disadvantages of the three solutions, such as signal strength and sample stability, but we conclude that EDTA and deionized formamide are the preferred loading solutions for sequencing applications.