Electrically gated nanoporous membranes for smart molecular flow control.

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Smart drug delivery systems require precise control over therapeutic molecule release.
• Field-effect gating offers a potential mechanism for low-power, electrically controlled transport.
• Nanoporous membranes provide a scaffold for fabricating miniaturized drug delivery devices.

Purpose of the Study:

• To develop and characterize a novel conductive nanoporous membrane platform for electrically controlled drug delivery.
• To investigate the use of field-effect gating for precise control of charged drug molecule transport.
• To evaluate the platform's efficacy in delivering glaucoma treatment molecules.

Main Methods:

• Fabrication of a functionalized anodic aluminum oxide (AAO) membrane with a Cr-Au-Cr stack.
• Functionalization involved creating an insulating layer for gate electrode control.
• Testing with oppositely charged drug molecules (ethacrynic acid and timolol maleate) at pH 7.4.

Main Results:

• A +2 V gate voltage increased negatively charged ethacrynic acid transport by 337% and decreased positively charged timolol maleate transport by 66%.
• A -2 V gate voltage decreased ethacrynic acid transport by 48% and increased timolol maleate transport by 116%.
• Surface treatment affected the on-off ratio (OOR), altering drug transport control, with results verified by simulations.

Conclusions:

• The developed conductive nanoporous membrane platform enables low-power, electrically controlled drug delivery via field-effect gating.
• The system demonstrates precise control over the transport of oppositely charged drug molecules.
• This technology holds potential for advanced smart drug delivery systems, particularly for conditions like glaucoma.