Subject(s)
Microscopy, Scanning Probe/instrumentation , Nanotechnology/instrumentation , 4-Chloro-7-nitrobenzofurazan/analogs & derivatives , Adhesiveness , Colloids , Elastin , Fluorescein-5-isothiocyanate , Fluorescent Dyes , Microscopy, Atomic Force/instrumentation , Microscopy, Atomic Force/methods , Microscopy, Scanning Probe/methods , Nanotechnology/methods , Printing , Spores, Bacterial , Static Electricity , StearatesABSTRACT
Atomic force microscope tips terminated with spore cells are used to directly pattern onto glass and tissue surfaces. The spore cells act as sponges and eliminate the need to use microfabricated ink reservoirs during lithography.
Subject(s)
Microscopy, Atomic Force/methods , Molecular Imprinting/methods , Spores , Cell Membrane , Glass , Microscopy, Atomic Force/instrumentationABSTRACT
Fourier transform infrared (FT-IR) spectroscopy is utilized to observe adsorbate interactions with a tissue-derived collagen scaffold extracted from the Bruch's membrane of pig eyes. The characterization includes conformational changes in isoleucine, polyisoleucine, collagen-binding peptide, RGD-tagged collagen-binding peptide, and laminin after adsorption onto the substrate. Isotopically labeled isoleucine is further utilized to understand changes in the biomolecular structure upon binding to a tissue-derived surface. The adsorbates associated with the collagen scaffold predominately through hydrophobic interactions and hydrogen bonding. The results of this study can be used to improve our understanding of surface chemistry changes during the engineering of biomimetic scaffolds before and after biomolecule adsorption.
Subject(s)
Spectroscopy, Fourier Transform Infrared/methods , Adsorption , Amino Acids/chemistry , Animals , Biomimetics , Bruch Membrane/metabolism , Collagen/chemistry , Hydrogen Bonding , Hydrophobic and Hydrophilic Interactions , Laminin/chemistry , Molecular Conformation , Peptides/chemistry , Surface Properties , SwineABSTRACT
AFM tips terminated with PMMA colloids are used to pattern molecules in both serial and parallel modes by allowing the polymer on the tip to swell under different humidity conditions. This extension of the dip-pen nanolithography technique provides an easy methodology to place inks on different substrates without the need to perform specialized tip alignment.
Subject(s)
Dimethylpolysiloxanes/chemistry , Nanotechnology/methods , Polymethyl Methacrylate/chemistry , Colloids/chemistry , Electrochemistry , Humidity , Microscopy, Atomic Force , Particle Size , Surface PropertiesABSTRACT
There has been extensive interest in the micro and nanoscale manipulation of various substrates in the past few decades. One promising technique is dip-pen nanolithography which has shown the capability to pattern substrates of all forms including, tissue-derived substrates. Patterning of tissue-derived substrates is of particular interest, as it would facilitate studies into controlling cell morphology and cell-substrate interaction. To expand the field into this area both peptides and bioactive collagen-binding peptide-linked biomolecules were patterned to the inner collagenous zone of the Bruch's membrane (BM). Collagen-binding peptide, and extra cellular matrix (ECM) proteins laminin and fibronectin were patterned on the BM and SiO(x). The lithographic protocol was facilitated by Triton X-100 which was used to clean the tissue-derived construct after harvesting. This produced a collagen-exposed BM which was more hydrophilic (contact angle 67 degrees +/-8.49 degrees) surface compared with other cleaning methods but it maintained similar surface roughness (root-mean-square) 80+/-18 nm and collagen exposure. This type of surface can be readily patterned with the chosen inks under lower humidity conditions.
