Meet Bio S&T A foreword by our CEO Upcoming conferences BAC library expertise 3 options BAC sequencing RFQ cDNA and DNA libraries Lambda cDNA/genomic Plasmid cDNA/genomic Normalized cDNA RFQ Gene synthesis Deliverables and guarantees RFQ Mutagenesis Deliverables and guarantees RFQ DNA sequencing Individual sequencing PCR products END EST clones Whole genome Technology portfolio Drug screening APA technology Sequencing technology APAgene GOLD Walking Kits Retroviral products Other custom services Contact info Site map   Normalized Plasmid cDNA library Bio S&T offers full-length-enriched and directionally cloned cDNA normalization service using our proprietary technology. O rder a normalized  plasmid cDNA library  for the low price of $3,998 (for at least 1,000,000 clones). Pricing is available for a higher amount of clones (example 107 ), please  contact us for more information! Optional: Duo-range libraries! Receive 2 sub-libraries of totalling 1.5 million clones. Each will have a different insert size range of your choice (ex: 500bp-2Kb and 2Kb-4Kb). This maximizes flexibility and representability. Add this feature for an additional $499. Optional: Clone array, library amplification, library copies and sequencing are all available at a very competitive rate. Please contact us for more information. Compared with other methods, our technology offers the following advantages: Representation of abundant transcripts greatly decreased (see Figure 1). Reduction of abundant transcripts is essential for discovery of rare transcripts. For a non-normalized cDNA library, usually 10–20 abundant genes account for at least 20% of the cellular mRNA mass; several hundred genes of medium abundance genes comprise 40–60% of the mRNA mass; several thousand rare genes (<10 mRNA copies per cell) may account for 20–40% of the mRNA mass. Hence, random sequencing of clones from non-normalized cDNA libraries is inefficient, and very costly, for discovering rare transcripts. Decreasing the percentage of these transcripts before sequencing, significantly increases the chance for rare gene discovery. cDNA normalization efficiency is strictly monitored. Apart from the normalization of cDNA population, a parallel normalization is performed. In the parallel normalization, a reporter gene is added to the cDNA population before normalization, as a control. The percentage of this control gene can be easily tested before and after normalization to ensure the quality of normalization. The enrichment of rare and unique sequences is accomplished by using our controlled normalization procedure that reduces the frequency of abundant sequences as much as 400 fold . Our Normalized cDNA molecules are longer (See Figure 2). Our normalization hybridization method prevents significant loss of average insert size. We perform normalization of cDNA population prior to cloning and library preparation. This prevents size bias against long and otherwise difficult-to-amplify cDNA due to clone bias. Normalized cDNA molecules are full-length-enriched. We use proprietary method to synthesize full-length enriched cDNA for normalization. DNA libraries rich in clones containing complete coding sequences with 5' and 3' untranslated regions (UTRs) for each transcript in a single cloning step are invaluable for high-throughput transcriptome analysis. Normalized cDNA molecules are directionally cloned. Directional cloning facilitates bi-directional sequencing, PCR screening and expression. Low vector background. Bio S&T uses efficient ligation, a high quality vector, as well as electroporation for cloning. As much as 99% of clones have inserts. Figure 1: Reduction in abundant transcripts after normalization.     Figure 2: Insert size determination of a normalized library:   Please note the absence of the redundant bands following the normalization procedure as well as the large size of the cDNAs.