O-Modifiers. Our 5′-Amino-Modifier C6 is our most popular modifier so we offer 5′-Amino-Modifier C6-PDA (1). For longer linkers, we offer the hydrophobic 5′-Amino-Modifier C12-PDA (2) and the hydrophilic 5′-Amino-ModifierTEG-PDA (3). The high conjugation efficiency of amino-modified oligonucleotides 8
prepared using PDA 5′-Amino-Modifiers is demonstrated in Figure 3. A T12 oligonucleotide was modified using 5′-Amino-Modifier C12-PDA. Following deprotection using AMA, very high coupling efficiency was observed. Further, the
5′-amino group was shown to have excellent conjugation potential by reaction with biotin NHS Ester in the normal fashion. Essentially quantitative conjugation efficiency was observed (Figure 3).
We thank Stefan Pitsch for his help in preparing this article. We also thank him for developing a product to address the problems of existing amino-modifiers by providing a new range of products with better stability and handling properties since they are granular powders rather than viscous oils.
1. Developed by Stefan Pitsch and ReseaChem GmbH (S. Berger), Patent pending.
Figure 3: pda-Off aminO-mOdified OligOnucleOtide and its biOtin cOnjugate
PDA-Off T12-C12 Amine Conjugated with Biotin NHS Ester
Key pOints
Oligonucleotides containing PDAamino-modified oligonucleotides must be treated with aqueous methylamine or AMA for complete deprotection. If ammonium hydroxide must be used, reaction at 55 will yield around 80% of the deprotected amino group, even with extended deprotection times.
PDA-Off T12-C12 Amine
orderIng InforMAtIon
Item Catalog No. Pack Price($)
5′-Amino-Modifier C6-PDA 5′-Amino-Modifier C12-PDA 5′-Amino-Modifier-TEG-PDA
10-1947-90 10-1947-02 10-1948-90 10-1948-02 10-1949-90 10-1949-02
100 ole 0.25g 100 ole 0.25g 100 ole 0.25g
30.00 100.00 65.00 240.00 105.00 420.00
9
NEw pROdUCt – 5′-stEaRyL phOsphORaMiditE – aN aLtERNatiVE LipOphiLiC CaRRiER
Synthetic oligonucleotides that have been modified chemically to achieve certain biological characteristics have found uses in therapeutic development. For example, antisense oligonucleotides, siRNA, aptamers and miRNA have all been found to have qualities that justify pharmaceutical development. As always, the challenge of such development has been to deliver the oligos effectively to the desired cellular targets. A variety of delivery strategies is currently in use but a favorite has been simple modification of the oligonucleotide at the 5′ terminus with a lipophilic and non-toxic carrier.1365970-03-1 Synonym For example, cholesterol-conjugated siRNAs have been shown to silence gene expression in vivo.144875-48-9 MedChemExpress In a review article,1 the authors described the preparation and use of siRNA modified with a variety of lipophilic carriers.PMID:29763040 They demonstrated that bile acids and long-chain fatty acid conjugates, in addition to cholesterol, help with siRNA delivery into cells with resulting silencing of gene expression. The authors note that efficient and selective uptake of these siRNA conjugates depends on interactions with lipoprotein particles, lipoprotein receptors and transmembrane proteins.1 Glen Research has supported these activities for several years with cholesterol and a-tocopherol carriers (1-3). We now offer a simple C18 lipid as an economical and effective carrier molecule. 2 We envisage that 5′-Stearyl Phosphoramidite (4) will become a favored lipophilic carrier for experimentation with synthetic oligonucleotides. 5′-Stearyl Phosphoramidite is not fully soluble in acetonitrile and must be dissolved in a mixt.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