Effects of Grafted Alkyl Groups on Aggregation Behavior of Amphiphilic Poly(aspartic acid)

Abstract

The aggregation behavior of biodegradable amphiphilic poly(aspartic acid) (PASP) derivatives containing long alkyl chains was characterized by size, interfacial properties, and aggregate formation. The polymers were synthesized by thermal condensation and aminolysis by alkylamine, followed by hydrolysis of the remaining succinimide units in the polymer backbone. The polymers formed self-aggregates by ultrasonication. Strong hydrophobic interaction by a higher amount of grafted alkyl chains induced higher aqueous stability of the self-aggregates. Bending of the stiff PASP backbone and strong association of alkyl chains were considered to be major competitive factors for determining aqueous stability. An aqueous solution of PASP-C18 was not surface-active due to physical cross-linker nature of octadecyl chains, while dodecyl and hexadecyl chains with higher chain flexibility showed surface-active properties. CAC calculated from fluorescence excitation spectra showed logarithmically decreasing behavior as DS of alkyl chains.

Membrane-Anchoring, Comb-Like Pseudopeptides for Efficient, pH-Mediated Membrane Destabilization and Intracellular Delivery

“…This was due to the enhanced intermolecular and intramolecular interactions resulting from incorporation of hydrophobic side chains. 26,27 The size change of the pseudopeptides as a function of pH was also depicted in Figure 2.…”

Multifunctional Cu1.94S-Bi2S3@polymer nanocomposites for computed tomography imaging guided photothermal ablation

“…Here, the lactam ring in PSI chain is easily opened via aminolysis by OAm to form PSI OAm with a long hydrophobic side-chain [47], and the lactam part also can be readily hydrolyzed to carboxyl group under alkaline condition. Together with its amphiphilic and biodegradable properties, the PSI OAm that has been extensively used for surface functionalization of inorganic nanomaterials and construction of drug delivery nanocapsules [48,49], was employed as a coating agent to fabricate the nanocomposites. The morphology and size of the hydrophobic Cu 1.94 S and Bi 2 S 3 precursors and hydrophilic Cu 1.94 S-Bi 2 S 3 @PSI OAm nanocomposites were characterized by TEM (Fig.…”

光热响应的Cu7S4@pNIPAm纳米载体应用于可控的药物/光热治疗

“…S3). Polyaspartic acid (PASP), due to its high water-soluble and biodegradable property, has become a kind of excellent functional materials for drug delivery and encapsulation of NPs [51,52]. The lactam ring of PSI is easy to be opened by amino group, which forms PASP derivatives with a side-chain functional group [53][54][55][56].…”