A5019640674- Click Chemistry and Applications
- Advanced Polymer Synthesis and Characterization
- biodegradable polymer synthesis and properties
- Bacteriophages and microbial interactions
- Advanced biosensing and bioanalysis techniques
- Polymer composites and self-healing
- Photopolymerization techniques and applications
- Polymer crystallization and properties
- Carbon dioxide utilization in catalysis
- RNA Interference and Gene Delivery
- Protein Degradation and Inhibitors
- Ubiquitin and proteasome pathways
- Multiple Myeloma Research and Treatments
- Chemical Synthesis and Analysis
- Mycobacterium research and diagnosis
- Glycosylation and Glycoproteins Research
- Tuberculosis Research and Epidemiology
- Advanced Biosensing Techniques and Applications
- Cancer Research and Treatments
- Monoclonal and Polyclonal Antibodies Research
- Pneumonia and Respiratory Infections
- Machine Learning in Materials Science
- Chemical Synthesis and Reactions
- Alkaloids: synthesis and pharmacology
- Ocular Infections and Treatments
Massachusetts Institute of Technology
2019-2025
Stanford University
2016-2018
University of California, Berkeley
2012-2018
Stanford Medicine
2016
Howard Hughes Medical Institute
2012-2015
Harvard University
2013
Fortune Institute of Technology
2009
Taichung Veterans General Hospital
2000
Significance Bioorthogonal chemistry has created new opportunities for interrogating biomolecules in cells and organisms. Near-infrared (NIR) fluorogenic probes activated by bioorthogonal are ideal imaging studies, as tissue penetrance is highest background fluorescence from excess probe endogenous minimized at these wavelengths. Here, we present the development optimization of NIR azide that undergo a enhancement up to 48-fold upon reaction with terminal or strained alkynes. In conjunction...
Many common polymers, especially vinyl are inherently difficult to chemically recycle and environmentally persistent. The introduction of low levels cleavable comonomer additives into existing polymerization processes could facilitate the production deconstructable recyclable variants with otherwise equivalent properties. Here, we report thionolactones that serve as for chemical deconstruction recycling polymers prepared through free radical polymerization, using polystyrene (PS) a model...
Fluorescent bioorthogonal smart probes across the visible spectrum will enable sensitive visualization of metabolically labeled molecules in biological systems. Here we present a unified design, based on principle photoinduced electron transfer, to access panel highly fluorogenic azide that are activated by conversion corresponding triazoles via click chemistry. Termed CalFluors, these possess emission maxima range from green far red wavelengths, and biomolecule detection under no-wash...
A solvatochromic trehalose dye conjugate allows the fast and specific detection of Mycobacterium tuberculosis in sputum samples.
Fluorogenic probes activated by bioorthogonal chemical reactions can enable biomolecule imaging in situations where it is not possible to wash away unbound probe. One challenge for the development of such a priori identification structures that will undergo dramatic fluorescence enhancement virtue transformation. With aid density functional theory calculations reported previously Nagano and co-workers, we identified azidofluorescein derivatives were predicted an increase quantum yield upon...
Vertebrate glycans constitute a large, important, and dynamic set of post-translational modifications that are notoriously difficult to manipulate image. Although the chemical reporter strategy has been used in conjunction with bioorthogonal chemistry image external glycosylation state live zebrafish detect tumor-associated mice, ability systemically within organism remained elusive. Here, we report method combines metabolic incorporation cyclooctyne-functionalized sialic acid derivative...
Convenient strategies for the deconstruction and reprocessing of thermosets could improve circularity these materials, but most approaches developed to date do not involve established, high-performance engineering materials. Here, we show that bifunctional silyl ether, i.e., R'O-SiR2-OR'', (BSE)-based comonomers generate covalent adaptable network analogues industrial thermoset polydicyclopentadiene (pDCPD) through a novel BSE exchange process facilitated by low-cost food-safe catalyst...
Thermosets present sustainability challenges that could potentially be addressed through the design of deconstructable variants with tunable properties; however, combinatorial space possible thermoset molecular building blocks (e.g., monomers, cross-linkers, and additives) manufacturing conditions is vast, predictive knowledge for how combinations these components translate to bulk properties lacking. Data science overcome problems, but computational methods are difficult apply...
Hydrogen fluoride (HF) is a versatile reagent for material transformation, with applications in self-immolative polymers, remodeled siloxanes, and degradable polymers. The responsive situ generation of HF materials therefore holds promise new classes adaptive systems. Here, we report the mechanochemically coupled from alkoxy-gem-difluorocyclopropane (gDFC) mechanophores derived addition difluorocarbene to enol ethers. Production involves an initial assisted rearrangement gDFC mechanophore...
"Drop-in" additives that introduce chemically cleavable bonds into thermosets without compromising thermomechanical properties could enable triggered material deconstruction and enhanced sustainability. While the installation of strands commercial thermoset polydicyclopentadiene (pDCPD) using comonomers facilitates chemical deconstruction, these can lower material's glass transition temperature (Tg). By contrast, crosslinkers pDCPD maintain or potentially increase Tg but does not facilitate...
Thermoset polymers and fiber-reinforced polymer composites possess the chemical, physical, mechanical properties necessary for energy-efficient vehicles structures, but their energy-inefficient manufacturing lack of end-of-life management strategies render these materials unsustainable. Here, we demonstrate deconstruction upcycling high-performance poly(dicyclopentadiene) (pDCPD) thermosets with a concurrent reduction in energy demand curing via frontal copolymerization. Triggered material...
ADVERTISEMENT RETURN TO ISSUEPREVLetterNEXTApproach to the Tricyclic Core of Tigliane–Daphnane Diterpenes. Concerning Utility Transannular Aldol AdditionsArthur J. Catino, Alexandra Sherlock, Peyton Shieh, Joseph S. Wzorek, and David A. Evans*View Author Information Department Chemistry Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States[email protected]Cite this: Org. Lett. 2013, 15, 13, 3330–3333Publication Date (Web):June 20,...
Abstract Vertebrate glycans constitute a large, important, and dynamic set of post‐translational modifications that are notoriously difficult to manipulate image. Although the chemical reporter strategy has been used in conjunction with bioorthogonal chemistry image external glycosylation state live zebrafish detect tumor‐associated mice, ability systemically within organism remained elusive. Here, we report method combines metabolic incorporation cyclooctyne‐functionalized sialic acid...
Prodrugs engineered for preferential activation in diseased versus normal tissues offer immense potential to improve the therapeutic indexes (TIs) of preclinical and clinical-stage active pharmaceutical ingredients that either cannot be developed otherwise or whose efficacy tolerability it is highly desirable improve. Such approaches, however, often suffer from trial-and-error design, precluding predictive synthesis optimization. Here, using bromodomain extra-terminal (BET) protein...
Permanently cross-linked polymer networks-thermosets-are often difficult to chemically deconstruct. The installation of cleavable bonds into the strands thermosets using comonomers as additives can facilitate thermoset deconstruction without replacement permanent cross-links, but such monomers lead reduced thermomechanical properties and require high loadings function effectively, motivating design new optimal additives. Here, we introduce "strand-fusing cross-linkers" (SFCs), which fuse two...
Abstract Permanently cross‐linked polymer networks—thermosets—are often difficult to chemically deconstruct. The installation of cleavable bonds into the strands thermosets using comonomers as additives can facilitate thermoset deconstruction without replacement permanent cross‐links, but such monomers lead reduced thermomechanical properties and require high loadings function effectively, motivating design new optimal additives. Here, we introduce “strand‐fusing cross‐linkers” (SFCs), which...
Bioorthogonal chemistry is an effective tool for elucidating metabolic pathways and measuring cellular activity, yet its use currently limited by the difficulty of getting probes past cell membrane into cytoplasm, especially if more complex are desired. Here we present a simple minimally perturbative technique to deliver functional glycosylation cells using nanostructured "nanostraw" delivery system. Nanostraws provide direct intracellular access through fluid conduits that remain small...
Microbial communities are important for the health of mucosal tissues. Traditional culture and gene sequencing have demonstrated bacterial populations on conjunctiva. However, it remains unclear if cornea, a transparent tissue critical vision, also hosts microbiome. Corneas wild-type, IL-1R (-/-) MyD88 C57BL/6 mice were imaged after labeling with alkyne-functionalized D-alanine (alkDala), probe that only incorporates into peptidoglycan metabolically-active bacteria. Fluorescence in-situ...
The concentrations of reactive oxygen species (ROS), e.g., H2O2, are often elevated in diseased tissue microenvironments. Therefore, the selective detection ROS could enable new diagnostic methods or tools for chemical biology. Here, we report synthesis boronic ester-bis-norbornene core-cross-linked brush-arm star polymers (BASPs) with polyethylene glycol (PEG) PEG-branch-spirocyclohexyl nitroxide (chex) shells. Size exclusion chromatography (SEC) and dynamic light scattering (DLS) showed...
Abstract Palmitoylation is a widespread, reversible lipid modification that has been implicated in regulating variety of cellular processes. Approximately one thousand proteins are annotated as being palmitoylated, and for some these, including several oncogenes the Ras Src families, palmitoylation indispensable protein function. Despite this wealth disease-relevant targets, there currently few effective pharmacological tools to interfere with palmitoylation. One reason lack development...
Directed evolution was used to improve the activity of JamB, a membrane-bound bifunctional desaturase/acetylenase. To quickly assess protein engineering outcomes, we developed new platform for quantifying extracellular alkyne-tagged metabolites through fluorogenic click reaction. Random mutagenesis yielded best JamB variant with ∼20-fold increased in E. coli.