A5091049741- Chemical Synthesis and Analysis
- Advanced Polymer Synthesis and Characterization
- Supramolecular Self-Assembly in Materials
- biodegradable polymer synthesis and properties
- Polydiacetylene-based materials and applications
- Mass Spectrometry Techniques and Applications
- Molecular Sensors and Ion Detection
- Advanced biosensing and bioanalysis techniques
- Organometallic Complex Synthesis and Catalysis
- Material Dynamics and Properties
- Wikis in Education and Collaboration
- Photochromic and Fluorescence Chemistry
- Lanthanide and Transition Metal Complexes
- Synthetic Organic Chemistry Methods
- Oral History, Memory, Narrative Analysis
- Open Education and E-Learning
- Biochemical and Structural Characterization
- Phase Equilibria and Thermodynamics
- Culinary Culture and Tourism
- Polymer Surface Interaction Studies
- Academic Writing and Publishing
- Glycosylation and Glycoproteins Research
- RNA and protein synthesis mechanisms
- Protein Structure and Dynamics
- Planetary Science and Exploration
University of North Carolina at Chapel Hill
2020-2024
Planetary Science Institute
2022
University of California, Santa Barbara
2016-2019
California NanoSystems Institute
2019
University of California System
2015-2017
University of California, Berkeley
2013-2017
Berkeley College
2015-2017
Santa Barbara City College
2016
Division of Materials Research
2016
Coram
2001
Polymer sequence programmability is required for the diverse structures and complex properties that are achieved by native biological polymers, but efforts towards controlling of synthetic polymers are, comparison, still in their infancy. Traditional provide robust chemically materials, control over monomer sequences limited. The modular step-wise synthesis peptoid on other hand, allows precise sequences, affording opportunities these chains to fold into well-defined nanostructures. Hundreds...
A versatile strategy is reported for the multigram synthesis of discrete oligomers from commercially available monomer families, e.g., acrylates, styrenics, and siloxanes. Central to this identification reproducible procedures separation oligomer mixtures using automated flash chromatography systems with effectiveness approach demonstrated through preparation libraries (Đ = 1.0). Synthetic availability, coupled accurate structural control, allows these functional building blocks be harnessed...
We present a one-photon visible light-responsive micellar system for efficient, on-demand delivery of small molecules. Release is mediated by novel class photochromic material - donor-acceptor Stenhouse adducts (DASAs). demonstrate controlled molecules such as the chemotherapeutic agent (paclitaxel) to human breast cancer cells triggered switching with low intensity, light.
Abstract The utility of Meldrum's activated furan (MAF) for the colorimetric detection sub ppm levels amines in solution, on solid supports, and as vapors is reported. MAF synthesized one step from inexpensive commercially available starting materials exhibits high selectivity primary secondary presence competing nucleophiles. reaction between furans results a distinct color change, discernable by naked eye. UV/Vis absorption spectroscopy was utilized to monitor reactions solution determine...
Protein-mimetic amphiphiles have significant promise as a platform to access the complex functions of natural biological materials and incorporate tunability environmental resilience synthetic materials. The fields polymer chemistry chemical biology concurrently approached development biomimetic with ranging from random amphiphilic copolymers peptide–lipid conjugates. In this Perspective, we strategies diverse arenas for controlling assembled morphologies dynamics protein-mimetic...
Macromolecule sequence, structure, and function are inherently intertwined. While well-established relationships exist in proteins, they more challenging to define for synthetic polymer nanoparticles due their molecular weight, conformational dispersities. To explore the impact of sequence on nanoparticle we synthesized a set 16 compositionally identical, sequence-controlled polymers with distinct monomer patterning dimethyl acrylamide bioinspired, structure-driving di(phenylalanine) (FF)....
Inspired by marine siderophores that exhibit a morphological shift upon metal coordination, hybrid peptide-polymer conjugates assemble into different morphologies based on the nature of ion coordination have been designed. Coupling peptide chelator, hexahistidine, with hydrophobic oligostyrene allows modular strategy to be established for efficient synthesis and purification these tunable amphiphiles (oSt(His)6). Remarkably, in presence divalent transition ions (Mn, Co, Ni, Cu, Zn, Cd)...
Hexavalent chromium [Cr(VI)] is a worldwide water contaminant that currently without cost-effective and efficient remediation strategies. This in part due to lack of ligands can bind it amid an excess innocuous ions aqueous solution. We present herein the design application peptoid-based library ligand candidates for toxic metal ions. A selective screening process was used identify members Cr(VI) species at neutral pH presence large spectator There were 11 sequences identified, their...
The triple-helix stereocomplex of poly(methyl methacrylate) (PMMA) is a unique example multistranded synthetic helix that has significant utility and promise in materials science nanotechnology. To gain fundamental understanding the underlying assembly process, discrete stereoregular oligomer libraries were prepared by combining stereospecific polymerization techniques with automated flash chromatography purification. Stereocomplex these building blocks enabled identification (1) minimum...
While methods for polymer synthesis have proliferated, their functionality pales in comparison to natural biopolymers-strategies are limited building the intricate network of noncovalent interactions necessary elicit complex, protein-like functions. Using a bioinspired di(phenylalanine) acrylamide (FF) monomer, we explored impact various generating ordered assembled structures. Amphiphilic copolymers were synthesized that exhibit β-sheet-like local structure upon collapsing into single-chain...
Synthetic polymers are a modular solution to bridging the two most common classes of catalysts: proteins and small molecules. Polymers offer synthetic versatility small-molecule catalysts while simultaneously having ability construct microenvironments mimicking those natural proteins. We synthesized panel polymeric containing novel triphenylphosphine acrylamide monomer investigated how their properties impact rate model Suzuki-Miyaura cross-coupling reaction. Systematic variation polymer...
Cadmium poisoning poses a serious health concern due to cadmium's increasing industrial use, yet there is currently no recommended treatment. The selective coordination of cadmium in biological environment-i.e. the presence serum ions, small molecules, and proteins-is difficult task. To address this challenge, combinatorial library peptoid-based ligands has been evaluated identify structures that selectively bind human with minimal chelation essential metal ions. Eighteen unique were...
Both natural biomaterials and synthetic materials benefit from complex energy landscapes that provide the foundation for structure-function relationships environmental sensitivity. Understanding these nonequilibrium dynamics is important development of design principles to harness this behavior. Using a model system poly(ethylene glycol) methacrylate-based thermoresponsive lower critical solution temperature (LCST) copolymers, we explored impact composition stimulus path on thermal...
The selective binding of uranyl for extraction from seawater by using polymer sorbents holds promise as a sustainable source uranium nuclear energy. A combinatorially synthesized peptoid library (N-substituted glycine oligomers) was screened with the goal identifying high-affinity ligands use in sorbents. Qualitative screening techniques dye, arsenazo III, identified three uranyl-binding sequences, all which contained only carboxylic acids active groups. Fluorescence spectroscopy used to...
VIEWPOINT: REVISIONISM AND REVOLUTION: MEXICO COMPARED TO ENGLAND FRANCE Get access Alan Knight University of Texas at Austin Search for other works by this author on: Oxford Academic Google Scholar Past & Present, Volume 134, Issue 1, February 1992, Pages 159–199, https://doi.org/10.1093/past/134.1.159 Published: 01 1992
ABSTRACT From readily available starting materials, we report a facile synthesis of lipid–polymer conjugates (LPCs). Easy access to multigram quantities dialkyl lipid chain transfer agent allows range LPCs be prepared bearing well‐defined hydrophilic polymer head‐groups, controlled molecular weights and low dispersity by photoelectron RAFT polymerization (PET‐RAFT). As dictated the packing parameters, resulting were suitable for solution‐phase self‐assembly, both independently in combination...
Peptoid ligands were conjugated to fluorescent pyrene yielding a platform for the selective detection of metal ions in complex samples.
ABSTRACT The synthesis and systematic comparison of a comprehensive library well‐defined polymer architectures based on poly(acrylic acid) is reported. Through the development new synthetic methodologies, linear, single branched, precision‐branched comb, star polymers were prepared their performance as dispersants was evaluated. ability to accurately control chain lengths branch points allows subtle interplay between structure dispersant be defined affords critical insights into design...
Inspired by nanotechnologies based on DNA strand displacement, herein we demonstrate that synthetic helical exchange can be achieved through tuning of poly(methyl methacrylate) (PMMA) triple-helix stereocomplexes. To evaluate the utility and robustness exchange, stereoregular PMMA/polyethylene glycol (PEG) block copolymers capable undergoing crystallization driven self-assembly via stereocomplex formation were prepared. Micelles with spherical or wormlike morphologies formed varying...
Diblock oligomeric peptide-polymer amphiphiles (PPAs) are biohybrid materials that offer versatile functionality by integrating the sequence-dependent properties of peptides with synthetic versatility polymers. Despite their potential as biocompatible materials, rational design PPAs for assembly into multi-chain nanoparticles remains challenging due to complex intra- and intermolecular interactions emanating from polymer peptide segments. To systematically explore impact monomer architecture...
A model system of peptidomimetics was developed to characterize the complex conformational ensembles compositionally identical disordered peptoids using a suite analyses, including rapid colorimetric technique.
Diblock oligomeric peptide-polymer amphiphiles (PPAs) are biohybrid materials that offer versatile functionality by integrating the sequence-dependent properties of peptides with synthetic versatility polymers. Despite their potential as biocompatible materials, rational design PPAs for assembly into multi-chain nanoparticles remains challenging due to complex intra- and intermolecular interactions emanating from polymer peptide segments. To systematically explore impact monomer architecture...
Complex interactions between non-coordinating residues are significant yet commonly overlooked components of macromolecular catalyst function. While these have been demonstrated to impact binding affinities and catalytic rates in metalloenzymes, the roles similar structural elements synthetic polymeric catalysts remain underexplored. Using a model Suzuki-Miyuara cross-coupling reaction, we performed series systematic studies probe interconnected effects metal-ligand cross-links,...
The synthetic toolbox for stimuli-responsive polymers has broadened to include many variables of tunable control, making these materials applicable in diverse technologies. However, unraveling the key composition-structure-function relationships facilitate ground-up design remains a challenge due inherent dispersity sequence and conformations polymers. We here present systematic study using model system copolymers with thermoresponsive (N-isopropylacrylamide) backbone addition...