Protocol-Dependent Effects on Colloidal Characterization and Drug Loading/Release Analysis of Thermosensitive...

Area of Science:

• Polymer Science
• Materials Science
• Nanotechnology

Background:

• Thermosensitive microgels, like PNIPAM-co-COOH, are promising for drug delivery.
• Accurate characterization is crucial for understanding their behavior and optimizing performance.
• Existing methods can be influenced by experimental protocols, leading to inaccuracies.

Purpose of the Study:

• To analyze protocol-dependent effects on microgel characterization and drug delivery.
• To quantify and minimize experimental biases in analyzing thermosensitive microgels.
• To establish a robust framework for reliable microgel analysis.

Main Methods:

• Dynamic Light Scattering (DLS) with drift correction
• 3D-DLS combined with Static Light Scattering (SLS)
• Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM)
• Nanoparticle Tracking Analysis (NTA), Laser Diffraction (LD)

Main Results:

• Standard DLS underestimates collapsed radius by 18% due to thermal convection.
• 3D-DLS and SLS accurately describe thermal collapse, swelling, and core-corona structure.
• Drug loading efficiency is maximized near the volume phase transition temperature.
• Dialysis requires free-drug blanks for accurate drug release kinetics.

Conclusions:

• Methodological refinements are essential for accurate characterization of thermosensitive microgels.
• Optimized protocols reduce experimental bias in colloidal and drug delivery studies.
• The established framework can be applied to other soft nanocarriers.