Synthesis, Internalization and Visualization of N-(4-Carbomethoxy) Pyrrolidone Terminated PAMAM [G5:G3-TREN] Tecto(dendrimers) in Mammalian Cells

Abstract

Tecto(dendrimers) are well-defined, dendrimer cluster type covalent structures. In this article, we present the synthesis of such a PAMAM [G5:G3-(TREN)]-N-(4-carbomethoxy) pyrrolidone terminated tecto(dendrimer). This tecto(dendrimer) exhibits nontraditional intrinsic luminescence (NTIL; excitation 376 nm; emission 455 nm) that has been attributed to three fluorescent components characterized by different fluorescence lifetimes. Furthermore, it has been shown that this PAMAM [G5:G3-(TREN)]-N-(4-carbomethoxy) pyrrolidone terminated tecto(dendrimer) is able to form a polyplex with double stranded DNA, and is nontoxic for HeLa and HMEC-1 cells up to a concentration of 10 mg/mL, even though it accumulates in endosomal compartments as demonstrated by its unique NTIL emission properties. Many of the above features would portend the proposed use of this tecto(dendrimer) as an efficient transfection agent. Quite surprisingly, transfection activity could not be demonstrated in HeLa cells, and the possible reasons are discussed in the article.

Unique Property of Nontraditional Intrinsic Luminescence in the Transforming of Solution‐Hydrogel‐Solid and Its Applications

“…The above special features in the changing from solution to gel are presumed to be mainly due to the abnormal emissive mechanism for amine‐containing NTIL compounds, namely, aggregates of amine groups act as the real fluorescent centers. [ 15,16,25,31–33 ] In solution, fluorescent centers exist in a relatively relaxed microenvironment, the amine groups in aggregates usually undergo dynamic movements in a much larger space, and the loose and flexibly structure will cause more extended electron delocalization and the varied excited status with many different energy levels, resulting in the longer‐wavelength fluorescent peak and EDF. On the contrary, in hydrogel, most amine groups are anchored in 3D network, which affecting the fluorescent behaviors in two aspects.…”

Osteogenic Differentiation of Human Mesenchymal Stem Cells by the Single Action of Luminescent Polyurea Oxide Biodendrimers

“…PURE dendrimers have a pH-dependent blue fluorescence. The fluorescence of dendrimers and other polymers without possessing classic chromophores, referred as a NTIL, has been widely observed and reported. − Similar to its counterparts, PURO biodendrimers also show a blue fluorescence. However, the emission intensity is higher and permanent, not being influenced by pH changes (both in intensity and emission wavelength).…”

Multicompartment dendrimicelles with binary, ternary and quaternary core composition

“…Well-defined systems are key to developing novel nanoscopic materials with emerging properties and the work presented here opens up a range of applications of these dendrimicelles in materials or medicinal areas. Controlling the micelle core composition also allows for the design of new supermolecule structures in which the micelles act as templates to allow chemical cross-linking of the core components, resulting in new classes of materials, such as tectodendrimers, 56,57 or…”