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Updated: Sep 26, 2026
Formulation and Characterization of Bioactive Agent Containing Nanodisks
Published on: March 17, 2023
Cell membrane electrostatically cloaked dendrimeric nanocarbons for high-bioactivity and -stability natural drug
Xinran Yu1, Sha Liu2, Zhiran Cheng2
1School of Pharmaceutical Sciences, Fuchun Campus, Zhejiang Chinese Medical University, Hangzhou 311402, China; Zhejiang Key Laboratory of Chinese Medicine Modernization, Zhejiang Chinese Medical University, Hangzhou 311402, China.
Hypothesis:
The strong interface interactions such as covalent bonding between cell membranes (CMs) and carriers are usually necessary to stabilize formed biocomposites, which exerts destructive impacts on the structure and bioactivity of CMs. Systematic regulation of interface interactions may be an effective approach to reconcile biocomposite stability with bioactivity. We hypothesized that the strength of electrostatic interaction between negatively charged CMs and positively charged dendrimeric nanocarbon surfaces can be facilely tuned by the generation of polyamidoamine (PAMAM) dendrimers, which enabled an optimal balance between membrane protein bioactivity and biomimetic colloidal stability.
Experiments:
PAMAM dendrimers with 1.0, 3.0, 5.0 and 7.0 generations (G) were covalently grafted onto magnetic carbonaceous nanospheres (MCSs) to create dendrimeric MCSs (DMCSs) with stepwise increasing surface positive charges. CMs electrostatically cloaked DMCSs (CM@DMCSs) were assembled via electrostatic self-assembly. Their bioactivity (EGFR kinase activity), stability (CM retention under vigorous shaking) and CM loading capacity were evaluated as tuning PAMAM generation and zeta potential.
Findings:
Moderate electrostatic attraction (3.0 G PAMAM, zeta potential +36.3 mV) preserved 91.1% of membrane protein activity, significantly higher than covalent immobilization (55.7%), while achieving high stability (74.49% retention after 11 h) and enhanced loading capacity (41.90 mg/g). Higher generations (≥5.0 G) improved stability marginally but severely compromised bioactivity, revealing a clear activity-stability trade-off governed by interfacial electrostatic force. The optimized CM@DMCSs exhibited superior selective extraction of five bioactive components from Curcuma longa L., including a novel pro-osteogenic compound demethoxycurcumin. This work establishes a universal interfacial design principle for biofunctional nanomaterials via electrostatic engineering.
