Vitamin E‑Labeled Polyethylenimine for <i>in vitro</i> and <i>in vivo</i> Gene Delivery

A series of Vitamin E (vitE)-labeled PEIs (PEI-vitE_<i>n</i>) were synthesized and showed excellent complexation ability with plasmid DNA (pDNA). The cellular uptake of PEI-vitE_<i>n</i>/pDNA complexes was greatly enhanced with the increase of vitE labeling, which is much better than that of control PEI25 in three different cell lines. PEI-vitE₆ showed the best performance in <i>gfp</i> pDNA delivery and following GFP expression in HEK-293A cells. In addition, <i>in vivo</i> gene delivery in living mice also confirmed that PEI-vitE₆ showed low toxicity and efficiently delivered <i>gfp</i> pDNA to the cells of liver and lung tissues for gene expression

Sensitive Detection of Single-Nucleotide Mutation in the BRAF Mutation Site (V600E) of Human Melanoma Using Phosphate–Pyrene-Labeled DNA Probes

A series of novel nucleotide phosphoramidites were rationally designed and synthesized and were then site-specifically incorporated in DNA oligonucleotide probes with pyrene-modified phosphate. These oligodeoxynucleotide (ODN) probes almost have no inherent fluorescence emission with pyrene modification at 3′ phosphate of corresponding nucleotides as a result of the photoinduced electron-transfer quenching effect of nucleobases (thymidine ∼ cytidine > guanosine ≫ adenosine). However, strong fluorescence emission was observed only with the perfectly matched duplex for the probes with pyrene modified at 3′ phosphate of thymidine and cytidine. These rationally designed ODN probes successfully worked as “turn on” fluorescence oligonucleotide sensors for single-nucleotide polymorphism (SNP) and were used for detecting a single BRAF mutation site (V600E) of human melanoma