A novel microfluidic device that can selectively and specifically isolate exceedingly small numbers of circulating tumor cells (CTCs) through a monoclonal antibody (mAB) mediated process by sampling large input volumes (≥1 mL) whole blood directly in short time periods (<37 min) was demonstrated. The CTCs were concentrated into (190 nL), the number captured read without labeling using an integrated conductivity sensor following release from capture surface. contained series (51) high-aspect...

We report here the chemical modification of poly(methyl methacrylate) (PMMA) surfaces by their reaction with monoanion α,ω-diaminoalkanes (aminolysis reaction) to yield amine-terminated PMMA surfaces. It is found that amine functionalities are tethered backbone through an alkane bridge amide bonds formed during aminolysis surface ester functionalities. The distribution termini quite uniform as judged fluorescence micrographs. electroosmotic flow in aminated microchannels reversed when...

ADVERTISEMENT RETURN TO ISSUEPREVFeaturesNEXTPeer Reviewed: Polymeric Microelectromechanical Systems.When it comes to microfluidic devices, plastic substrates are more versatile and easier machine than glass.Steven A. Soper, Sean M. Ford, Shize Qi, Robin L. McCarley, Kevin Kelly, Michael C. MurphyCite this: Anal. Chem. 2000, 72, 19, 642 A–651 APublication Date (Web):October 1, 2000Publication History Published online1 October 2000Published inissue 1...

An exciting new direction in responsive liposome research is endogenous triggering of liposomal payload release by overexpressed enzyme activity affected tissues and offers the unique possibility active site-specific release. Bringing to fruition fully expected capabilities this class triggered delivery system requires a collection systems that respond different upregulated enzymes; however, relatively small number currently exist. Here we show stable, ∼100 nm diameter liposomes can be made...

An on-column contact conductivity detector was developed for the analysis of various mono- and polyanionic compounds separated by electrophoresis chips fabricated in poly(methyl methacrylate) (PMMA) using hot embossing techniques from Ni electroforms. The consisted a pair Pt wires (127 microm diameter) with an end-to-end spacing approximately 20 situated within fluidic channel. waveform applied to electrode bipolar pulse frequency 5.0 kHz used reduce charging current measurement so that...

A frontier area in the development of activatable (turn-on) fluorescence-based probes is that concerned with rapid and selective stimulus triggering probe activation so as to allow for biomarker identification cellular imaging. The work here a cloaked fluorophore composed reporter whose fluorescence efficiently quenched by it being bound an trigger group through novel self-immolative linker. Highly achieved chemical enzymatic means result activated detachment from linker, latter subsequently...

Achieving the vision of identifying and quantifying cancer-related events targets for future personalized oncology is predicated on existence synthetically accessible economically viable probe molecules fully able to report presence these in a rapid highly selective sensitive fashion. Delineated here are design evaluation newly synthesized turn-on whose intense fluorescent reporter signature revealed only through activation by specific intracellular enzyme present tumor cells multiple...

The ability to detect and visualize cellular events their associated target biological analytes through use of cell-permeable profluorogenic probes is dependent on the availability activatable that respond rapidly selectively by production fluorescent reporting molecules whose excitation emission energies span a broad range. Herein described new probe, DCM–Cys, preferentially reacts with cysteine form dicyanomethylene-4H-pyran (DCM) reporter red-energy fluorescence can be stimulated...

Low-density arrays were assembled into microfluidic channels hot-embossed in poly(methyl methacrylate) (PMMA) to allow the detection of low-abundant mutations gene fragments (K-ras) that carry point with high diagnostic value for colorectal cancers. Following spotting, chip was a cover plate and array accessed using microfluidics order enhance kinetics associated hybridization. The configured zip code sequences (24-mers) complementary present on target. hybridization targets generated an...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMobility of the alkanethiol-gold (111) interface studied by scanning probe microscopyRobin L. McCarley, David J. Dunaway, and Robert WillicutCite this: Langmuir 1993, 9, 11, 2775–2777Publication Date (Print):November 1, 1993Publication History Published online1 May 2002Published inissue 1 November 1993https://pubs.acs.org/doi/10.1021/la00035a007https://doi.org/10.1021/la00035a007research-articleACS PublicationsRequest reuse permissionsArticle...

The ability to form patterns of chemically reactive surface functionalities in microanalytical devices using a simple photopatterning approach without the need for photoresist-based methods is described. Direct UV exposure surfaces poly(methyl methacrylate), PMMA, and poly(carbonate), PC, microfluidic through optical masks leads production near monolayer quantities carboxylic acid groups as determined by coverage, X-ray photoelectron spectroscopy, fluorescence microscopy experiments....

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSurface-Confined Monomers on Electrode Surfaces. 1. Electrochemical and Microscopic Characterization of .omega.-(N-Pyrrolyl)alkanethiol Self-Assembled Monolayers AuRobert J. Willicut Robin L. McCarleyCite this: Langmuir 1995, 11, 1, 296–301Publication Date (Print):January 1995Publication History Published online1 May 2002Published inissue 1 January...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTElectrochemical Polymerization of Pyrrole-Containing Self-Assembled Alkanethiol Monolayers on AuRobert J. Willicut and Robin L. McCarleyCite this: Am. Chem. Soc. 1994, 116, 23, 10823–10824Publication Date (Print):November 1, 1994Publication History Published online1 May 2002Published inissue 1 November 1994https://pubs.acs.org/doi/10.1021/ja00102a073https://doi.org/10.1021/ja00102a073research-articleACS PublicationsRequest reuse permissionsArticle...

Terthiophene and anthracene, both of which in positive mode form only molecular radical cations (M+•) upon laser irradiation (λ = 337 nm) at near-threshold powers, were used as matrices for matrix-assisted desorption/electron-transfer ionization metallocenes (1,2-diferrocenylethane, ferrocene, decamethylferrocene) a methylene-bridged bisphenol, 2,2'-methylenebis(6-tert-butyl-4-methylphenol). In the mass spectra these matrix/analyte combinations, formation protonated molecules was not...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTScanning tunneling microscopy studies of gold(111) derivatized with organothiolsYeon Taik Kim, Robin L. McCarley, and Allen J. BardCite this: Phys. Chem. 1992, 96, 18, 7416–7421Publication Date (Print):September 1, 1992Publication History Published online1 May 2002Published inissue 1 September 1992https://pubs.acs.org/doi/10.1021/j100197a052https://doi.org/10.1021/j100197a052research-articleACS PublicationsRequest reuse permissionsArticle...

To build highly specific surfaces using aptamer affinity reagents, the effects of linker and coadsorbents were investigated for maximizing target binding specificity aptamer-based self-assembled monolayers (SAMs) supported on gold. An that binds protein thrombin was utilized as a model system to compare different mixed monolayer systems toward selectivity immobilized aptamer. Important factors used optimize characteristics films include changes in design elements coadsorbent thiols. Binding...

A brush with success: Responsive brushes composed of poly(N-isopropylacrylamide) grafted onto a poly(thiophene) backbone display the highest water solubility ever reported for neutral as well temperature-dependent optical properties and solubilities (see picture). The graft polymer exhibits shifts in π–π* transition near collapse temperature chains.

We have prepared two peptides based on the hydrophobic core (Lys-Leu-Val-Phe-Phe) of amyloid beta-protein (Abeta) that contain alpha,alpha-disubstituted amino acids at alternating positions, but differ in positioning oligolysine chain (AMY-1, C-terminus; AMY-2, N-terminus). studied effects AMY-1 and AMY-2 aggregation Abeta find that, stoichiometric concentrations, both completely stop fibril growth. Equimolar mixtures form only globular aggregates as imaged by scanning force microscopy...

A systematic study is reported on the effect of linker size and its chemical composition toward ligand binding to a surface-immobilized aptamer, measured using surface plasmon resonance. The results, thrombin as model system, showed that number thymidine (T) units in increases from 0 20 four separate increments (T(0), T(5), T(10), T(20)), density aptamer decreased linearly approximately 25 12 pmol x cm(-2). decrease occurred due increased molecules. In addition, capacity was shown increase...

NAD(P)H:quinone oxidoreductase type I (NQO1) is a target enzyme for triggered delivery of drugs at inflamed tissue and tumor sites, particularly those that challenge traditional therapies. Prodrugs, macromolecules, molecular assemblies possessing trigger groups can be cleaved by environmental stimuli are vehicles with the potential to yield active drug only prescribed sites. Furthermore, quinone propionic acids (QPAs) covalently attached prodrugs or liposome surfaces removed application...

It is of great importance to interrogate the impact local environment on transport small molecules across lipid bilayers, as they are key function and capabilities eukaryotic cells liposome-based delivery systems. Herein described real-time studies molecular adsorption kinetics positively charged small-molecule organic dyes at surface liposomes under different buffer salt conditions, made possible by application second harmonic generation (SHG). The malachite green (MG) within liposome...

Fast, selective, and noninvasive reporting of intracellular cancer-associated events species will lead to a better understanding tumorigenesis at the molecular level development precision medicine approaches in oncology. Overexpressed reductase presence solid tumor cells is key cancer progression protection those diseased from oxidative effects therapeutics meant kill them. Human NAD(P)H:quinone oxidoreductase isozyme I (hNQO1), cytoprotective 2-electron-specific found unusually high...

Achieving highly selective and sensitive detection/visualization of intracellular biological events through the use cell-penetrable, bioanalyte-activatable, turn-on probes is dependent on presence specific event-linked cellular biomarkers, if only there exist activatable that appropriately respond to biomarker analyte. Here described evaluation of, in imaging studies, a previously undisclosed naphthalimide probe QMeNN, whose fluorescence deactivated by photoinduced electron transfer (PeT)...