Jinho Hyun

This article describes the fabrication and characterization of stimulus-responsive elastin-like polypeptide (ELP) nanostructures grafted onto omega-substituted thiolates that were patterned onto gold surfaces by dip-pen nanolithography (DPN). In response to external stimuli such as changes in temperature or ionic strength, ELPs undergo a switchable and reversible, hydrophilic-hydrophobic phase transition at a lower critical solution temperature (LCST). We exploited this phase transition behavior

We describe the molecular recognition-mediated, stepwise fabrication of patterned protein nanostructures with feature sizes on the order of 200 nm. First, a self-assembled monolayer (SAM) of 16-mercaptohexadecanoic acid (MHA) is patterned onto gold by dip-pen nanolithography (DPN), and the unpatterned regions are passivated with a protein-resistant oligoethylene glycol-terminated alkanethiol SAM. Next, an amine-terminated biotin derivative is covalently conjugated with the chemically activated M

Microstamping on an activated polymer surface (MAPS) is a methodology that enables biomolecules to be patterned on polymers with micrometer spatial resolution. MAPS combines homogeneous surface derivatization of a polymer to introduce a reactive functional group followed by reactive microcontact printing (μCP) of a biological ligand of interest, linked to an appropriate reactive group. We demonstrate here that polyethylene, polystyrene, poly(methyl methacrylate), and poly(ethylene terephthalate)

This paper describes a simple strategy to biochemically manipulate a surface at the nanoscale by enzyme dip-pen nanolithography using an endonuclease (DNase I) that is directly patterned on a self-assembled monolayer presenting a terminal oligonucleotide. Physisorbed nanopatterns of DNase I carried out nanoscale enzymology at the surface creating oligonucleotide patterns with the fidelity of the patterned enzyme because of the affinity of the enzyme for the immobilized, oligonucleotide substrate

We describe the in situ synthesis of nanometer thick films of polystyrene (PS) on a self-assembled monolayer (SAM) on gold by surface-initiated free radical polymerization and further demonstrate that three-dimensional polymer structures with micrometer lateral resolution and nanometer vertical resolution can be fabricated by combining microcontact printing (μCP) with surface-initiated polymerization (SIP). We implemented SIP onto a COOH-terminated SAM on gold using a sequential approach to coup

Gluconacetobacter xylinus (G. xylinus) metabolism is activated by oxygen, which makes the formation of an air-medium interface critical. Here we report solid matrix-assisted 3D printing (SMAP) of an incubation medium surface and the 3D fabrication of bacterial cellulose (BC) hydrogels by in situ biosynthesis of G. xylinus. A printing matrix of polytetrafluoroethylene (PTFE) microparticles and a hydrogel ink containing an incubation medium, bacteria, and cellulose nanofibers (CNFs) are used in th

Long‐term, spatially resolved attachment and growth of mammalian cells in a biologically relevant milieu on a variety of substrates is possible using the micropatterning techniques presented here (see cover). Two general methods, both involving microcontact printing of an amphiphilic comb polymer (see Figure) and incubation with a protein‐containing solution are reported.

It is not easy to design structures with transparent solutions, especially in light projection three-dimensional (3D) printing, since the penetration of light in solution is limitless. Here, silk fibroin incorporated with melanin nanoparticles (SFM) is used as a transparency modifier of poly(ethylene glycol)-tetraacrylate (PEG4A) solution. The incorporation of melanin into the SF hydrogel is performed in the range of 0.05-0.2% (w/v), and the SFM was added to the PEG4A precursor solution at 0.25-