Size selective sampling using mobile, 3D nanoporous membranes

We describe the fabrication of 3D membranes with precisely patterned surface nanoporosity and their utilization in size selective sampling. The membranes were self-assembled as porous cubes from lithographically fabricated 2D templates (Leong et al., Langmuir 23:8747–8751, 2007) with face dimensions of 200 μm, volumes of 8 nL, and monodisperse pores ranging in size from approximately 10 μm to 100 nm. As opposed to conventional sampling and filtration schemes where fluid is moved across a static membrane, we demonstrate sampling by instead moving the 3D nanoporous membrane through the fluid. This new scheme allows for straightforward sampling in small volumes, with little to no loss. Membranes with five porous faces and one open face were moved through fluids to sample and retain nanoscale beads and cells based on pore size. Additionally, cells retained within the membranes were subsequently cultured and multiplied using standard cell culture protocols upon retrieval.

[1]  Sean P. Palecek,et al.  Engineering the Stem Cell Microenvironment , 2007, Biotechnology progress.

[2]  Hung Li,et al.  Isolation and Characterization of Size‐Sieved Stem Cells from Human Bone Marrow , 2002, Stem cells.

[3]  G. Whitesides,et al.  Self-assembled monolayers of thiolates on metals as a form of nanotechnology. , 2005, Chemical reviews.

[4]  Elazer R. Edelman,et al.  Adv. Drug Delivery Rev. , 1997 .

[5]  K. Schütze,et al.  Isolation by size of epithelial tumor cells : a new method for the immunomorphological and molecular characterization of circulatingtumor cells. , 2000, The American journal of pathology.

[6]  S. Zhang.  Molecular Self-assembly , 2001 .

[7]  G. Whitesides,et al.  Autonomous Movement and Self‐Assembly , 2002 .

[8]  Shoji Kimura,et al.  MODELS OF MEMBRANE TRANSPORT PHENOMENA AND THEIR APPLICATIONS FOR ULTRAFILTRATION DATA , 1982 .

[9]  P. Athanassiadou,et al.  Recent advances in the detection of bone marrow micrometastases: A promising area for research or just another false hope? A review of the literature , 2007, Cancer and Metastasis Reviews.

[10]  P. Price,et al.  Tracks of Charged Particles in Solids. , 1965, Science.

[11]  Andrea I. Schäfer,et al.  Nanofiltration: Principles and Applications , 2004 .

[12]  C L Gerlach,et al.  Bioseparation and bioanalytical techniques in environmental monitoring. , 1998, Journal of chromatography. B, Biomedical sciences and applications.

[13]  Johan Pihl,et al.  Microfluidic technologies in drug discovery. , 2005, Drug discovery today.

[14]  H. Liljestrand,et al.  Effects of physical-chemical characteristics on the sorption of selected endocrine disruptors by dissolved organic matter surrogates. , 2003, Environmental science & technology.

[15]  David H Gracias,et al.  3D lithographically fabricated nanoliter containers for drug delivery. , 2007, Advanced drug delivery reviews.

[16]  D. Gracias,et al.  Surface tension-driven self-folding polyhedra. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[17]  Rakesh K. Singh,et al.  Choosing an appropriate bioseparation technique , 1996 .

[18]  T. Park,et al.  Integration of Cell Culture and Microfabrication Technology , 2003, Biotechnology progress.

[19]  H. Yu,et al.  Use of an immunomagnetic separation–fluorescent immunoassay (IMS–FIA) for rapid and high throughput analysis of environmental water samples , 1998 .

[20]  David H Gracias,et al.  Remote radio-frequency controlled nanoliter chemistry and chemical delivery on substrates. , 2007, Angewandte Chemie.

[21]  E. Alden,et al.  Neonatal heelstick blood culture. , 1980, Pediatrics.

[22]  Sean P. Palecek,et al.  3-D microwell culture of human embryonic stem cells. , 2006, Biomaterials.

[23]  Jin-Woo Choi.  Fabrication of micromachined magnetic particle separators for bioseparation in microfluidic systems. , 2006, Methods in molecular biology.