Nanoporous Platforms for Cellular Sensing and Delivery

Abstract

Abstract:In recent years, rapid advancements have been made in the biomedical applications of micro and nanotechnology. While the focus of such technology has primarily been on in vitro analytical and diagnostic tools, more recently, in vivo therapeutic and sensing applications have gained attention. This paper describes the creation of monodisperse nanoporous, biocompatible, silicon membranes as a platform for the delivery of cells. Studies described herein focus on the interaction of silicon based substrates with cells of interest in terms of viability, proliferation, and functionality. Such microfabricated nanoporous membranes can be used both in vitro for cell-based assays and in vivo for immunoisolation and drug delivery applications.

Comparison of resistance to protein adsorption and stability of thin films derived from α-hepta-(ethylene glycol) methyl ω-undecenyl ether on HSi(111) and HSi(100) surfaces

“…Using silicon as substrates for preparation of such devices is attractive, since the microfabrication techniques well developed by the microelectronic industries can be used to fabricate and integrate various microcomponents into the devices. For reducing biofouling, considerable research has been directed to the modification of substrate surfaces with stable and ultrathin films of poly(ethylene glycol) (PEG) or oligo(ethylene glycol) (OEG) [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. Since many of the ultimate applications for biodevices require moderate-term (few hours to several days) exposure to biological media (e.g., buffer of pH 7.4 at 37 • C), stability of the biocompatible coatings on the devices under these conditions is highly desirable [24].…”

Microtechnologies for Drug Delivery

“…The pore size of the device can be controlled through micromolding, which can be advantageous for drug release kinetics. By controlling the pore size of drug delivery devices, traditional concentration-dependent diffusion kinetics can be turned into zero-order kinetics, such as can be seen with silicon membranes [ 12,[101][102][103][104]127 ] and is predicted for drug release from titanium nanotubes [ 128 ] . A system wherein triggered release of therapeutics has been developed through sili- con micromachining, photolithographic, and chemical vapor deposition processes was developed by Langer, Cima, and colleagues [ 35 ] .…”

Inorganic Nanoporous Membranes for Immunoisolated Cell-Based Drug Delivery

“…2). 82,83 First, a support ridge structure is photo-lithographically etched to provide mechanical support to the final structure. 80 A low-stress silicon nitride layer is deposited over the top surface of the wafer.…”