Angewandte Chemie International Edition. August 20, 2018, Vol. 57 Issue 34, p11074, 4 p.
Laboratories -- Equipment and supplies and Laboratory equipment
Byline: Pawel L. Urban Keywords: instrumentation; open-source electronics; prototyping Abstract Open-source electronics and programming can augment chemical and biomedical research. Currently, chemists can choose from a broad range of low-cost universal electronic modules (microcontroller boards and single-board computers) and use them to assemble working prototypes of scientific tools to address specific experimental problems and to support daily research work. The learning time can be as short as a few hours, and the required budget is often as low as 50 USD. Prototyping instruments using low-cost electronic modules gives chemists enormous flexibility to design and construct customized instrumentation, which can reduce the delays caused by limited access to high-end commercial platforms. Supporting information: Additional Supporting Information may be found in the online version of this article As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. CAPTION(S): Supplementary
Kumar, Ashok A., Hennek, Jonathan W., Smith, Barbara S., Kumar, Shailendra, Beattie, Patrick, Jain, Sidhartha, Rolland, Jason P., Stossel, Thomas P., Chunda-Liyoka, Catherine, and Whitesides, George M.
CLINICAL pathology, BUSINESS partnerships, RAPID prototyping, and DEVELOPING countries
Despite the growth of research in universities on point-of-care (POC) diagnostics for global health, most devices never leave the laboratory. The processes that move diagnostic technology from the laboratory to the field--the processes intended to evaluate operation and performance under realistic conditions--are more complicated than they might seem. Two case studies illustrate this process: the development of a paper-based device to measure liver function, and the development of a device to identify sickle cell disease based on aqueous multiphase systems (AMPS) and differences in the densities of normal and sickled cells. Details of developing these devices provide strategies for forming partnerships, prototyping devices, designing studies, and evaluating POC diagnostics. Technical and procedural lessons drawn from these experiences may be useful to those designing diagnostic tests for developing countries, and more generally, technologies for use in resource-limited environments. [ABSTRACT FROM AUTHOR]
PEPTIDES, BIOCATALYSIS, ENZYMES, HYDROGELS, and PROTEINS
Switchable self-assemblies respond to external stimuli with a transition between near-equilibrium states. Although being a key to present-day advanced materials, these systems respond rather passively, and do not display autonomous dynamics. For autonomous behavior, approaches must be found to orchestrate the time domain of self-assemblies, which would lead to new generations of dynamic and self-regulating materials. Herein, we demonstrate catalytic control of the time domain of pH-responsive peptide hydrogelators in a closed system. We program transient acidic pH states by combining a fast acidic activator with the slow, enzymatic, feedback-driven generation of a base (dormant deactivator). This transient state can be programmed over orders of magnitude in time. It is coupled to dipeptides to create autonomously self-regulating, dynamic gels with programmed lifetimes, which are used for fluidic guidance, burst release, and self-erasing rapid prototyping. [ABSTRACT FROM AUTHOR]
SMALL molecules, MOLECULAR biology, HELICOBACTER pylori, ORGANIC compounds, and GRAM-negative bacteria
Sustained identification of innovative chemical entities is key for the success of chemical biology and drug discovery. We report the fragment-based, computer-assisted de novo design of a small molecule inhibiting Helicobacter pylori HtrA protease. Molecular binding of the designed compound to HtrA was confirmed through biophysical methods, supporting its functional activity in vitro. Hit expansion led to the identification of the currently best-in-class HtrA inhibitor. The results obtained reinforce the validity of ligand-based de novo design and binding-kinetics-guided optimization for the efficient discovery of pioneering lead structures and prototyping drug-like chemical probes with tailored bioactivity. [ABSTRACT FROM AUTHOR]
DiLauro, Anthony M., Lewis, Gregory G., and Phillips, Scott T.
Angewandte Chemie International Edition. May 18, 2015, Vol. 54 Issue 21, p6200, 6 p.
Polymerization, Plastics industry, and Polymers
Byline: Anthony M. DiLauro, Gregory G. Lewis, Scott T. Phillips Keywords: depolymerization; materials science; polymerization; polymers; selective laser sintering Abstract End-capped poly(4,5-dichlorophthalaldehyde) (PCl.sub.2PA), which is a new self-immolative CD.sub.r polymer with the unique capability of depolymerizing continuously and completely in the solid state when an end cap is cleaved from the polymer by reaction with a specific molecular signal, is described. End-capped poly(4,5-dichlorophthalaldehyde) is sufficiently stable to enable patterning of three-dimensional macroscopic polymeric materials by selective laser sintering. These unique materials are capable of 1) autonomously amplifying macroscopic changes in the material in response to specific molecular inputs, and 2) altering their responses depending on the identity of the applied signal. Thus, not only does end-capped PCl.sub.2PA provide new and unique capabilities compared to the small subset of existing CD.sub.r polymers, but it also provides access to a new class of stimuli-responsive materials. Author Affiliation: Department of Chemistry, The Pennsylvania State University, University Park, PA 16802 (USA) http://www.psu.edu/dept/phillipsgroup/index.html Article Note: This work was supported in part by the National Science Foundation (CHE-1150969; for the design and synthesis aspects of the work), Department of the Defense, Defense Threat Reduction Agency (HDTRA1-13-1-0039; for prototyping of stimuli-responsive materials), the Penn State MRSEC (DMR-0820404), and Louis Martarano. G.G.L. thanks the Eli Lilly and Company and the ACS Division of Analytical Chemistry for a fellowship. Supporting information: Additional Supporting Information may be found in the online version of this article As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. CAPTION(S): miscellaneous_information s1 s2 s3
The autonomous self‐regulation of a pH‐responsive peptide hydrogelator by internal biocatalytic feedback is reported by A. Walther and co‐workers in their Communication on page 13258 ff. The resulting dynamic hydrogels have a programmed lifetime and are suitable for applications in transient rapid prototyping and fluidic guidance. [ABSTRACT FROM AUTHOR]
Klapotke, Thomas M., Rusan, Magdalena, and Sabatini, Jesse J.
Angewandte Chemie International Edition. Sept 1, 2014, Vol. 53 Issue 36, p9665, 4 p.
Byline: Thomas M. Klapotke, Magdalena Rusan, Jesse J. Sabatini Keywords: blue flame colors; color performance; copper; pyrotechnics; sensitivities Abstract The generation of blue-light-emitting pyrotechnic formulations without the use of chlorine-containing compounds is reported. Suitable blue-light emission has been achieved through the generation of molecular emitting copper(I) iodide. The most optimal copper(I) iodide based blue-light-emitting formulation was found to have performances exceeding those of chlorine-containing compositions, and was found to be insensitive to various ignition stimuli. Author Affiliation: Ludwig Maximilian University Munich, Department of Chemistry, Butenandtstrasse 5-13, Haus D, 81377 Munchen (Germany) Pyrotechnics Technology and Prototyping Division, U.S. Army RDECOM-ARDEC, Picatinny Arsenal, NJ 08706-5000 (USA) Article Note: Financial support of this work by LMU, ARL, ONR, and ARDEC is gratefully acknowledged.
Sabatini, Jesse J., Koch, Ernst-Christian, Poret, Jay C., Moretti, Jared D., and Harbol, Seth M.
Angewandte Chemie International Edition. Sept 7, 2015, Vol. 54 Issue 37, p10968, 3 p.
Dioxin, Epoxy resins, Green technology, Sustainable development, and Chemical tests and reagents
Byline: Jesse J. Sabatini, Ernst-Christian Koch, Jay C. Poret, Jared D. Moretti, Seth M. Harbol Keywords: energetic materials; illumination; pyrotechnics; red flames; sustainable chemistry Abstract The development of a red, chlorine-free pyrotechnic illuminant of high luminosity and spectral purity was investigated. Red-light emission based solely on transient SrOH.sub.(g) has been achieved by using either 5-amino-1H-tetrazole or hexamine to deoxidize the combustion flame of a Mg/Sr(NO.sub.3).sub.2/Epon-binder composition and reduce the amount of both condensed and gaseous SrO, which emits undesirable orange-red light. The new formulations were found to possess high thermal onset temperatures. Avoiding chlorine in these formulations eliminates the risk of the formation of PCBs, PCDDs, and PCDFs. This finding, hence, will have a great impact on both military pyrotechnics and commercial firework sectors. Author Affiliation: Lutradyn-Energetic Materials Science & Technology, Burgherrenstrasse 132, 67661 Kaiserslautern (Deutschland) US Army Research Laboratory, Energetics Technology Branch, Maryland, 21005 (USA) US Army RDECOM-ARDEC, Pyrotechnics Technology & Prototyping Division, Picatinny Arsenal, New Jersey, 07806 (USA) US Army, 22nd Chemical Battalion, (Technical Escort), Edgewood Arsenal, Maryland, 21010 (USA) Supporting information: Additional Supporting Information may be found in the online version of this article As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. CAPTION(S): miscellaneous_information