Difference in microchip electrophoretic mobility between partially and fully PEGylated poly(amidoamine) dendrimers

Area of Science:

• Nanotechnology
• Polymer Chemistry
• Analytical Chemistry

Background:

• Poly(ethylene glycol)-conjugated poly(amidoamine) dendrimers (PEG-PAMAMs) are utilized in various biomedical applications.
• Characterizing the degree of PEGylation is crucial for understanding their properties and performance.
• Existing methods for PEG-PAMAM characterization can be time-consuming or lack precision.

Purpose of the Study:

• To investigate the electrophoretic mobility differences between partially and fully PEG-PAMAMs.
• To evaluate the utility of microchip capillary gel electrophoresis (MCGE) for distinguishing PEG-PAMAMs with varying PEGylation levels.
• To establish a correlation between MCGE-measured and calculated molecular weights for PEG-PAMAMs.

Main Methods:

• Preparation of partially and fully PEG-PAMAMs using monomethoxy PEG-nitrophenyl carbonate.
• Separation and analysis of PEG-PAMAMs using microchip capillary gel electrophoresis (MCGE).
• Comparison of electrophoretic migration patterns and molecular weight estimations.

Main Results:

• MCGE successfully achieved size-based separation of PEG-PAMAMs.
• Fully PEG-PAMAMs exhibited slower migration than partially PEG-PAMAMs of similar or larger sizes.
• High correlation coefficients (r > 0.98) were observed between MCGE-measured and calculated molecular weights for both types of PEG-PAMAMs.

Conclusions:

• MCGE is a valuable tool for differentiating PEG-PAMAMs based on their PEGylation degree.
• The observed differences in electrophoretic mobility provide insights into the structural variations between part-PEG-PAMAM and full-PEG-PAMAM.
• MCGE offers a reliable method for the characterization of PEG-PAMAMs with diverse PEGylation levels.