Temperature and pH-responsive "smart" carbon nanotube dispersions

Area of Science:

• Nanomaterials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Carbon nanotubes (CNTs) are hydrophobic nanomaterials that typically aggregate in bundles.
• Dispersing CNTs in aqueous solutions is crucial for biomedical applications.
• Controlling CNT dispersion and aggregation with external stimuli is highly desirable for actuation mechanisms.

Purpose of the Study:

• To develop stimuli-responsive aqueous dispersions of single-walled carbon nanotubes (SWNTs).
• To utilize environment-responsive polymers for controlling SWNT aggregation.
• To enable external control over SWNT dispersion and aggregation for potential biomedical applications.

Main Methods:

• Synthesized "smart" aqueous dispersions of SWNTs.
• Incorporated poly(N-isopropylacrylamide) (PNIPAAm) for temperature responsiveness.
• Incorporated Poly-L-lysine (PLL) for pH responsiveness.

Main Results:

• Demonstrated temperature-responsive dispersion/aggregation of SWNTs using PNIPAAm.
• Demonstrated pH-responsive dispersion/aggregation of SWNTs using PLL.
• Achieved external stimuli control over SWNT aqueous dispersions.

Conclusions:

• Developed novel "smart" SWNT aqueous dispersions responsive to temperature and pH.
• Environment-responsive polymers enable tunable control over SWNT aggregation.
• These smart dispersions hold promise for advanced biomedical applications requiring controlled nanomaterial behavior.