Related Experiment Video
Updated: Feb 13, 2026

Preparation of Silica Nanoparticles Through Microwave-assisted Acid-catalysis
Published on: December 16, 2013
Polyaspartic acid-anchored mesoporous silica nanoparticles for pH-responsive doxorubicin release
Abdul Hakeem1,2, Fouzia Zahid1, Guiting Zhan1
1National Engineering Research Center for Nanomedicine, Department of Nanomedicine and Biopharmaceuticals, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
Background:
Nanotechnology-based drug delivery systems exhibit promising therapeutic efficacy in cancer chemotherapy. However, ideal nano drug carriers are supposed to be sufficiently internalized into cancer cells and then release therapeutic cargoes in response to certain intracellular stimuli, which has never been an easy task to achieve.
Objective:
This study is to design mesoporous silica nanoparticles (MSNs)-based pH-responsive nano drug delivery system that is effectively internalized into cancer cells and then release drug in response to lysosomal/endosomal acidified environment.
Methods:
We synthesized MSNs by sol-gel method. Doxorubicin (DOX) was encapsulated into the pores as a model drug. Polyaspartic acid (PAsA) was anchored on the surface of mesoporous MSNs (P-MSNs) as a gatekeeper via amide linkage and endowed MSNs with positive charge.
Results:
In vitro release analysis demonstrated enhanced DOX release from DOX-loaded PAsA-anchored MSNs (DOX@P-MSNs) under endosomal/lysosomal acidic pH condition. Moreover, more DOX@P-MSNs were internalized into HepG2 cells than DOX-loaded MSNs (DOX@MSNs) and free DOX revealed by flow cytometry. Likewise, confocal microscopic images revealed that DOX@P-MSNs effectively released DOX and translocated to the nucleus. Much stronger cytotoxicity of DOX@P-MSNs against HepG2 cells was observed compared with DOX@MSNs and free DOX.
Conclusion:
DOX@P-MSNs were successfully fabricated and achieved pH-responsive DOX release. We anticipated this nanotherapeutics might be suitable contenders for future in vivo cancer chemotherapeutic applications.
Related Concept Videos
The Anchoring-and-Adjustment Heuristic
Anchoring Junctions
Lipids as Anchors
The carboxy-terminal of most of the prenylated proteins, such as Ras proteins, contains...
GPI Anchoring of Proteins in the ER Membrane
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
Tail-anchoring of Proteins in the ER Membrane
Amino acids

