With this product is shown in Figure 3. Although not problematical in the usage of the labelled oligonucleotide, a product containing multiple peaks is always worrisome to customers. We are happy to maintain the supply of this product but clearly a fluorescein phosphoramidite with a simpler structure designed only for 5′ labelling would be desirable. And so we introduce the 5’fluorescein phosphorDMT-on Phosphorylation amidite (3) whose sole role is to label the 5’terminus during Photolabile Support oligonucleotide synthesis. The product contains no Transcription Terminator 4,4′-dimethoxytrityl (DMT) group and can be added only 2- and 4-Thio-dT once at the 5’terminus, thereby
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terminating synthesis. Although this product is prepared using the 6carboxyfluorescein derivative, its spectral characteristics are identical to those derived from product (1) in Figure 1. 5’Fluorescein phosphoramidite can be used with the standard cycle of all DNA synthesizers. However, as with all minor bases and most labelling reagents, it will benefit from an extended coupling time of 3 minutes. To take advantage of the multicolor detection capability of modern DNA sequencers and genetic analyzers, further derivatives of 5′-fluorescein phosphoramidite with shifted absorbance and emission maxima would obviously be of interest. We are therefore happy to introduce the tetrachloro (4) and hexachloro (5) phosphoramidites as the first two in a series of fluorescein analogues.1903008-80-9 Biological Activity The use of these products is identical to their fluorescein parent, as described above.65725-11-3 IUPAC Name The spectral characteristics of these dyes are detailed in Table 1 and typical RP HPLC traces are shown in Figure 4.PMID:30855902 RHODAMINE DYES The fluorescein structure is very compatible with oligonucleotide synthesis because it is resistant to hydrolysis with ammonium hydroxide, even when elevated temperatures and extended deprotection times are used. Unfortunately, the same does not apply to rhodamine derivatives which are not sufficiently stable to survive conventional deprotection. These must be attached to amino-modified oligonucleotides using post-synthesis labelling techniques. Typically, an activated carboxylate, usually Nhydroxysuccinimide (NHS) ester, of the dye in solution in DMF or DMSO is conjugated with the amino-modified oligonucleotide in sodium carbonate/ bicarbonate buffer at pH 9. Although this technique is time consuming and places demands on the final purification to remove unconjugated dye, it is nevertheless routine and successful. We feel that our role at Glen Research is to offer interesting products as phosphoramidites but will offer the most popular rhodamine derivative (tetramethylrhodamine, TAMRA) as an NHS ester (6) as an interim step.
Some of our customers have The following HPLC conditions were used expressed an interest in labelling with Unpurified Oligo to produce the chromatograms shown on Prepared with Fluorescein cyanine dyes, as well as admiration for Pages 3,4 and 6: Phosphoramidite (1) their performance in labelled oligonucleotides. The commercial Column: Spherisorb ODS2 (150X4.6mm) ownership of these dyes is a story in itself but we are happy to introduce them here Detector: UV at 254nm (see SMALL PRINT page 4) and hope Flow: 1mL/min to maintain supply while stimulating Gradient: development of new uses for them. The Time 0.1M TEAA(%) Acetonitrile(%) two cyanine derivatives we are 0 97 3 introducing are Cy3TM (7).MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com