Dip-Pen Nanolithography (DPN) uses an AFM tip to deposit organic molecules through a meniscus onto underlying substrate under ambient conditions. Thus far, the methodology has been developed exclusively for gold using alkyl or aryl thiols as inks. This study describes first application of DPN write patterns with sub-100 nm dimensions directly two different semiconductor surfaces: silicon and gallium arsenide. Using hexamethyldisilazane (HMDS) ink in procedure, we were able utilize lateral...

The structure and magnetic properties of different types templated wires are compared in this study. A long DNA molecule was used to guide the assembly pyrrolidinone-capped Fe2O3 CoFe2O3 particles as well polylysine-coated gold nanoparticles. resulting DNA-templated were stretched onto silicon oxide surfaces using a receding meniscus procedure. coated, stretched, surface-bound characterized atomic force microscopy (AFM), (MFM), spectroscopic methods. results with respect wire correlated...

The study describes how DNA coated with magnetic nanoparticles remains biologically active and accessible to the BamH1 restriction enzyme. Long molecules are using electrostatic interactions. coated, stretched, surface-bound is incubated in enzyme that specifically recognizes any strand containing GGATCC base sequence clips DNA. We show that, despite presence of on DNA, still able recognize cleavage site effectively digest assembly.

Aims: Mesoporous silica nanoparticles (MSNs) were prepared and characterized to develop a drug delivery system by loading them with hydralazine functionalizing polyethylene glycol. These agents restore damaged cell membranes ameliorate abnormal mitochondria behavior induced the endogenous toxin acrolein. Such formulation shows potential as novel therapeutic agent. Results & discussion: MSNs encapsulated covalently linked glycol subsequently synthesized transmission-electron microscopy, N2...

In this study, a mesoporous silica nanoparticle (MSN)-based nerve growth factor (NGF) delivery system has been successfully embedded within an electroactive polypyrrol (Ppy). The spherical particles with ∼100 nm diameter possess large surface-to-volume ratio for the entrapment of NGF into pores MSNs while retaining their bioactivity. Direct incorporation MSN-NGF Ppy was achieved during electrochemical polymerization. loading amount and release profile from composite investigated by sandwich...

The stability of III-nitride semiconductors in various solutions becomes important as researchers begin to integrate them into sensing platforms. This study quantitatively compares the GaN surfaces with different polarities. type quantification is because it represents first step toward designing semiconductor material interfaces compatible solution conditions. A Ga- and N-polar was conducted by immersion deionized H(2)O, pH 5, 9, H(2)O(2) for 7 days. Inductively coupled plasma mass...

Abstract The mechanical damage to neurons and their processes induced by spinal cord injury (SCI) causes a progressive cascade of pathophysiological events beginning with the derangement ionic equilibrium collapse membrane permeability. This leads cumulative deterioration neurons, axons, tissue architecture cord. We have previously shown that application hydrophilic polymer polyethylene glycol (PEG) following or brain can rapidly restore integrity, reduce oxidative stress, impaired axonal...

DNA-templated nanoparticle (NP) chains were examined as potential magnetic resonance imaging (MRI) contrast agents using in vitro environments of the extracellular matrix and tissue. A 3-T clinical MRI scanner was utilized to examine compare image enhanced by dispersed NPs, NP chains, gold-superparamagnetic multicomponent polyelectrolyte encapsulated, both T1-weighted T2-weighted images. In addition, longitudinal transverse relaxivity (r1 r2) changes measured basement membrane, Matrigel,...

Wide bandgap semiconductors such as gallium nitride (GaN) exhibit persistent photoconductivity properties. The incorporation of this asset into the fabrication a unique biointerface is presented. Templates with lithographically defined regions controlled roughness are generated during semiconductor growth process. Template surface functional groups varied using benchtop functionalization procedure. conductivity template altered by exposure to UV light and behavior PC12 cells mapped under...

In situ functionalization of polar (c plane) and nonpolar (a gallium nitride (GaN) was performed by adding (3-bromopropyl) phosphonic acid or propyl to a phosphoric etch. The target modulate the emission properties oxide formation GaN, which explored through surface characterization with atomic force microscopy, X-ray photoelectron spectroscopy, photoluminescence (PL), inductively coupled plasma–mass spectrometry, water contact angle. use in demonstrated lower amounts greater hydrophobicity...

A methodology to place and stretch long DNA molecules by coupling dip‐pen Nanolithography with molecular combing is presented. Templates were fabricated on SiO x surfaces using a positively charged polymer, poly(allylamine hydrochloride). Upon combing, elongate the surface (for example, see Figure) are localized presence of lithographically defined structures.

Synthetic TAT peptides designed to contain an arginine rich basic unit can bind RNA with affinity and specificity of a full-length protein. Therefore, deducing strategies immobilize such short surfaces enable one study their unique recognition properties in various types sensor platforms. In this paper, we present strategy 15-residue peptide (CGISYGRKKRRQRRR) the form nanoscopic features on SiOx surfaces. The protocol is based dip-pen nanolithography that results formation covalent...

The small leucine-rich proteoglycans (SLRPs), prevalent in collagenous tissues, regulate collagen fibrillogenesis and provide a host of biochemical cues critical to tissue function homeostasis. Incorporating SLRPs may enhance engineering designs that mimic the native extracellular matrix, although purified from animal sources bear low yields lack design control. Consequently, we have designed synthetic peptidoglycans, inspired by SLRP decorin, contain collagen-binding peptide attached...

Polyethylene glycol (PEG)-coated silica colloids circulating in the bloodstream target only injured tissues, particularly a spinal-cord injury (see picture). The PEG coating both seals and induces repair of damaged cells, leading to recovery physiological function. These PEG-coated have been characterized, tested ex vivo spinal cord living adult Guinea pig injury.

Gallium nitride is a wide band gap semiconductor that demonstrates unique set of optical and electrical properties as well aqueous stability biocompatibility. This combination makes gallium strong candidate for use in chemical biological applications such sensors neural interfaces. Molecular modification can be used to enhance the functionality surface. Here, surfaces were functionalized with PC12 cell adhesion promoting peptide using covalent affinity driven attachment methods. The scheme...