Papers by JENNIFER CECILIA BARRON MARTINEZ
Acta Biologica Colombiana, Jun 24, 2010
El acceso a los recursos genéticos por parte de los grupos de investigación en Colombia se evaluó... more El acceso a los recursos genéticos por parte de los grupos de investigación en Colombia se evaluó mediante la revisión de sus proyectos de investigación reportados en la base de datos nacional GrupLAC de Colciencias, hasta diciembre de 2008, con el fin de hacer una aproximación al estado del acceso a los recursos genéticos en el país. Del total de grupos revisados un 13,7% tienen acceso a recursos genéticos. Los grupos de investigación trabajan con un total de 252 especies diferentes que comprenden plantas, animales, bacterias, hongos y virus. En cuanto al origen del material, un 61% se encuentra en condiciones in situ y un 33% en condiciones ex situ. La mayor parte de las técnicas utilizadas en las investigaciones son moleculares (76%). Las instituciones que tienen grupos de investigación que trabajan en proyectos relacionados con acceso a recursos genéticos se agruparon en 10 categorías dentro de las cuales se destacan las universidades tanto privadas (29%) como públicas (39%), así como los centros de investigación de carácter privado (12%). Por otro lado, es muy bajo el porcentaje (1,0%) de proyectos de investigación cuyos resultados pueden llegar a tener un potencial de comercialización, ya que del total de 595 proyectos para los que se ha encontrado evidencia de acceso a recursos genéticos, solo seis proyectos han generado resultados protegibles por patentes. Ninguno de los proyectos examinados tiene contrato de acceso a recursos genéticos.
Acta Biologica Colombiana, Jun 24, 2010
The potato plant is the fourth most important crop in the world. In Colombia around 2.8 million t... more The potato plant is the fourth most important crop in the world. In Colombia around 2.8 million tons are produced annually economically supporting 90000 families. In the
Fluorescent metal nanoclusters were prepared.
Physical chemistry chemical physics : PCCP, Jan 20, 2015
Water-soluble cationic conjugated poly(phenylene vinylene) (PPV) and cationic fullerene were comp... more Water-soluble cationic conjugated poly(phenylene vinylene) (PPV) and cationic fullerene were complexed with negatively charged single stranded DNA and double stranded DNA via electrostatic interactions to achieve photoinduced charge transfer with efficiencies as high as those observed from oppositely charged, cationic PPV and anionic fullerene but with distinctly different quenching mechanisms.
Single Molecule Spectroscopy and Superresolution Imaging VII, 2014
Here we present an automated microscope capable of 3D multi-color single molecule localization of... more Here we present an automated microscope capable of 3D multi-color single molecule localization of individual messenger RNA molecules in a wide range of cell types. We have implemented astigmatic imaging with a cylindrical lens to improve z-localization, and a maximum likelihood estimator on a graphics processing unit to improve localization precision and speed. This microscope will aid in gene expression analysis by its capability to perform high throughput imaging of thick cells and tissues while still maintaining sufficient z resolution to resolve single RNA transcripts in three dimensions. Enhanced z-localization allows for resolving membrane localized and co-localized transcripts.
Chemical Science, 2015
Fabrication of a unique white light LED from a stimuli-responsive organic molecule is reported. E... more Fabrication of a unique white light LED from a stimuli-responsive organic molecule is reported. Emission properties are dominated by the pH of the solution through intermolecular charge transfer.
Chem. Sci., 2015
A series of fluorescent unnatural amino acids (UAAs) bearing stilbene and meta-phenylenevinylene ... more A series of fluorescent unnatural amino acids (UAAs) bearing stilbene and meta-phenylenevinylene (m-PPV) backbone have been synthesized by palladium-catalyzed Heck couplings.
IEEE Nanotechnology Magazine, 2011
We demonstrated controlled conversion of DNA/Ag NCs between bright and dark states and designed a... more We demonstrated controlled conversion of DNA/Ag NCs between bright and dark states and designed a new molecular probe, NCB, for homogeneous detection of nucleic acid targets. Not relying on Forster energy transfer as the fluorescence on/off switching mechanism, NCBs have the potential to reach an ultrahigh S/B ratio in molecular sensing. Since the fluorescence enhancement is caused by intrinsic nucleobases, our detection technique is simple, inexpensive, and compatible with commercial DNA synthesizers. Here, we demonstrated that a palette of NCB light-up colors can be produced from the same origin by employing different proximal sequences. We also showed that the NC-nucleation sequences capable of achieving strong red fluorescence enhancement share a common 5'-C3NNNNNC4 motif.
Frontiers in Pathogen Detection: From Nanosensors to Systems, 2009
We ha ve developed a waveguide-based optical biosensor for the sensitive and specific detection o... more We ha ve developed a waveguide-based optical biosensor for the sensitive and specific detection of biomarkers associated with disease. Our technology combines the superior optical properties of single-mode planar waveguides, the robust nature of functionalized self-assembled monolayer sensing films and the specificity of fluorescence sandwich immunoassays to detect biomarkers in complex biological samples such as serum, urine and sputum. We have previously reported the adaptation of our technology to the detection of biomarkers associated with breast cancer and anthrax. However, these approaches primarily used phospholipid bilayers as the functional film and organic dyes (ex: AlexaFluors) as the fluorescence reporter. Organic dyes are easily photodegraded and are not amenable to multiplexing because of their narrow Stokes' shift. Here we have developed strategies for conjugation of the detector antibodies with quantum dots for use in a multiplex detection platform. We have previously evaluated dihydroxylipoic acid quantum dots for the detection of a breast cancer biomarker. In this manuscript, we investigate the detection of the Bacillus anthracis protective antigen using antibodies conjugated with polymer-coated quantum dots. Kinetics of binding on the waveguide-based biosensor are reported. We compare the sensitivity of quantum dot labeled antibodies to those labeled with AlexaFluor and demonstrate the photostability of the former in our assay platform. In addition, we compare sulfydryI labeling of the antibody in the hinge region to that of nonspecific amine labeling. This is but the first step in developing a multiplex assay for such biomarkers on our waveguide platform.
APL Materials, 2014
Non-equilibrium deposition of phase pure Cu 2 O thin films at reduced growth temperature
The Journal of Physical Chemistry C, 2010
All chemicals were purchased from Sigma-Aldrich and used as received. Nanopure Millipore water (1... more All chemicals were purchased from Sigma-Aldrich and used as received. Nanopure Millipore water (18.2 M Ω) was used in preparation of buffer solutions. Buffer solutions were prepared by dissolving powders into nanopure water, and adjusting the pH with 1 M NaOH and/or 1 M HCl. All reactions were carried out in 50 mL disposable Falcon™ tubes. The bulk fluorescence properties of the Au nanoclusters were analyzed by recording their emission and excitation spectra on a Varian Cary Eclipse Fluorescence Spectrometer. All spectra were recorded using preset conditions (medium scan rate, medium detector PMT, and using a 3 mL volume cuvette). Chemical names and abbreviations in Table 1 of manuscript are: 4-(2-Hydroxyethyl)piperazine-1-ethanesulfonic acid (HEPES); 2-(N-Morpholino)ethanesulfonic acid (MES); 4-(2-Hydroxyethyl)piperazine-1-propanesulfonic acid (EPPS); 3-(N-Morpholino)propanesulfonic acid (MOPS); 1,4-Piperazinediethanesulfonic acid (PIPES); 2-(Cyclohexylamino)ethanesulfonic acid (CHES); 1-(2-Hydroxyethyl)piperidine (HP); N-[Tris(hydroxymethyl)methyl]-2-aminoethanesulfonic acid (TES); and N,N-Bis(2-hydroxyethyl)-2-aminoethanesulfonic acid (BES). In a typical experiment, an aqueous HAuCl 4 solution (0.2 wt%, 1 mL) was added to a Good's buffer solution (5 mL, 100 mM) at room temperature, and inverted several times to mix. This mixed solution was then placed in shaking incubator (250 rpm, 37 o C) for three days (maximal fluorescence was observed after three days and no increase in fluorescence was observed thereafter). After synthesis, a clear solution was obtained with nonfluorescence nanoparticle precipitates on the bottom of the tubes. Control experiments included the Good's buffers, without gold, and the buffers at 0.1 M with 0.1 M H 2 O 2. All control experiments were incubated at 37 o C for 3 days or at room temperature for 4 days. No fluorescence was observed from the oxidized product of MES, even though H 2 O 2 is a known MES oxidant (Figure S1).[1] Additionally, oxidation of MES by gold is known to be rapid and concurrent with nanparticle formation, yet no fluorescence was observed when Good's buffer-stabilized nanoparticles were formed.[2] Potassium cyanide (500 mM) was added to preformed gold-MES nanoclusters. The
Nucleic Acids Research, 2006
In the use of non-antibody proteins as affinity reagents, diversity has generally been derived fr... more In the use of non-antibody proteins as affinity reagents, diversity has generally been derived from oligonucleotide-encoded random amino acids. Although specific binders of high-affinity have been selected from such libraries, random oligonucleotides often encode stop codons and amino acid combinations that affect protein folding. Recently it has been shown that specific antibody binding loops grafted into heterologous proteins can confer the specific antibody binding activity to the created chimeric protein. In this paper, we examine the use of such antibody binding loops as diversity elements. We first show that we are able to graft a lysozyme-binding antibody loop into green fluorescent protein (GFP), creating a fluorescent protein with lysozyme-binding activity. Subsequently we have developed a PCR method to harvest random binding loops from antibodies and insert them at predefined sites in any protein, using GFP as an example. The majority of such GFP chimeras remain fluorescent, indicating that binding loops do not disrupt folding. This method can be adapted to the creation of other nucleic acid libraries where diversity is flanked by regions of relative sequence conservation, and its availability sets the stage for the use of antibody loop libraries as diversity elements for selection experiments.
Langmuir, 2008
We report a general procedure to prepare functional organic thin films for biological assays on o... more We report a general procedure to prepare functional organic thin films for biological assays on oxide surfaces. Silica surfaces were functionalized by self-assembly of an amine-terminated silane film using both vapor- and solution-phase deposition of 3&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-aminopropylmethyldiethoxysilane (APMDES). We found that vapor-phase deposition of APMDES under reduced pressure produced the highest quality monolayer films with uniform surface coverage, as determined by atomic force microscopy (AFM), ellipsometry, and contact angle measurements. The amine-terminated films were chemically modified with a mixture of carboxylic acid-terminated poly(ethylene glycol) (PEG) chains of varying functionality. A fraction of the PEG chains (0.1-10 mol %) terminated in biotin, which produced a surface with an affinity toward streptavidin. When used in pseudo-sandwich assays on waveguide platforms for the detection of Bacillus anthracis protective antigen (PA), these functional PEG surfaces significantly reduced nonspecific binding to the waveguide surface while allowing for highly specific binding. Detection of PA was used to validate these films for sensing applications in both buffer and complex media. Ultimately, these results represent a step toward the realization of a robust, reusable, and autonomous biosensor.
Journal of the Academy of Marketing Science, 2010
As green marketing strategies become increasingly more important to firms adhering to a triple-bo... more As green marketing strategies become increasingly more important to firms adhering to a triple-bottom line performance evaluation, the present research seeks to better understand the role of "green" as a marketing strategy. Through an integration of the marketing, management, and operations literatures, an investigative framework is generated that identifies the various stakeholders potentially impacted through the environmentally friendly efforts of a firm. Specifically, the interconnected nature of the core business disciplines of marketing, management (both strategy and human resources), and operations are examined as controllable functions within an organization from which strategies can be enacted to affect a firm's stakeholders. The prior research in these areas is examined to identify potential research opportunities in marketing while also offering a series of representative research questions that can help guide future research in marketing.
Journal of Consumer Affairs, 2011
Environmental concern has been an important topic for more than 40 years and has recently become ... more Environmental concern has been an important topic for more than 40 years and has recently become even more critical with today's concerns about creating a sustainable and healthy environment. This research examines factors affecting an individual's willingness to pay more for an environmentally friendly product. Our results show that willingness to pay more differs across demographic groups. We also find that individuals who rate concern for waste as highly important are willing to spend more money on an eco-friendly product. Consequently, our findings provide insight into the development of appropriate educational strategies for different consumer groups to encourage consumers to purchase eco-friendly products, with a goal of creating a healthier environment for current and future generations.
Journal of Advertising, 2012
ABSTRACT This study assesses consumer perceptions of advertising messages for two proenvironmenta... more ABSTRACT This study assesses consumer perceptions of advertising messages for two proenvironmental products by examining the effectiveness of environmental versus personal benefit appeals and .99 versus .00 price endings. The authors borrow from Prospect Theory and Mental Accounting Theory to explain consumers&#39; perceptions of psychological pricing and product attributes. In addition, the moderating role of environmental skepticism is assessed as it relates to the effectiveness of environmentally friendly advertisements. Results indicate that consumers feel that some products advertised with environmental appeals are more costly, but are not perceived as lower quality as compared with products advertised with personal benefits. Findings also indicate a price ending × appeal interaction for two different products, but the effects vary between the products. Finally, environmental skepticism is found to moderate perceptions of the message appeal. Implications are provided.
Chemical Communications, 2010
Au fibers with micron-scale lengths have been successfully prepared via a solution-phase syntheti... more Au fibers with micron-scale lengths have been successfully prepared via a solution-phase synthetic method. Solubilization of salicylate ion into an aqueous CTAB solution forms rod-shaped micelles and becomes a key shape directing factor to generate one-dimensional Au structures.
Chem. Commun., 2011
S1. Sequence of aptamer-AgNC chimera DNA: 5′-AGTCCGTGGTAGGGCAGGTTGGGGTGACTAAAAACCCTTAATCCCC-3′ Se... more S1. Sequence of aptamer-AgNC chimera DNA: 5′-AGTCCGTGGTAGGGCAGGTTGGGGTGACTAAAAACCCTTAATCCCC-3′ Sequence of DNA chimera [thrombin aptamer (blue) and nanocluster templating sequence (red)]. 5′-GAGAGAGAGAGCCCAGTTCGGAGGGGGGG AAAAACCCTTAATCCCC-3' Sequence of random (control) DNA chimera. S2. Synthesis of aptamer-AgNCs: Briefly, 3 µM DNA chimera or control DNA (Integrated DNA Technologies, HPLC purified) and 18 µM AgNO 3 (Sigma Aldrich) were sequentially added and mixed with sodium phosphate buffer (20 mM, pH 6.6), and the reaction mixture was incubated at room temperature, in the dark, for 20 minutes. 18 µM NaBH 4 (Sigma Aldrich) was added and the reaction mixture was incubated at room temperature, in the dark, for one hour. Following reduction of Ag + ions, highly fluorescent aptamer-AgNCs were produced with fluorescence emission at 700 nm. The pH of the solution was raised to approximately pH 7 by addition of NaOH. NaCl (50 mM final concentration) was then added to the aptamer-AgNCs
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Papers by JENNIFER CECILIA BARRON MARTINEZ