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Abstract The Cu(II)‐mediated Chan‐Lam coupling reaction offers several benefits for developing point‐of‐care detection devices on microelectrode arrays. However, achieving selectivity on borate ester‐based polymer surfaces has proven difficult due to background reactions. Fluorescence‐based studies were conducted using fluorescently labeled acetylene nucleophiles. Initial experiments revealed significant background fluorescence across the electrode array, indicating selectivity issues. Further investigation uncovered significant background reactions occurring even without copper. To address this, a strategy utilizing an arylbromide‐based polymer was developed, enhancing reaction selectivity by minimizing background non‐specific reactions. Exploration into the confinement mechanism revealed the role of acetylene in forming dimers, facilitating rapid consumption of Cu(II) reagents that escaped from the specific electrodes used. These findings offer a way to construct devices for the multiplex point‐of‐care detection of metabolites, improving performance and accuracy in diagnostic devices. 

Structural supercapacitors, capable of bearing mechanical loads while storing electrical energy, hold great promise for enhancing mobile system efficiencies. However, developing practical structural supercapacitors often involves a challenging balance between mechanical and electrochemical performance, particularly in their electrolytes. Traditional research has focused on bi-continuous phase electrolytes (BPEs), which typically comprise high liquid content that weakens mechanical strength, and inert solid phases that hinder ion conduction and block electrode surfaces. Our previous work introduces a novel approach with a hydrated polymer electrolyte, demonstrating enhanced multifunctionality. This electrolyte, derived from controlled hydration of PET-LiClO₄, forms a trihydrate (LiClO₄∙3H₂O) structure, where water molecules bond with ions without forming a liquid phase, thereby improving ion mobility while maintaining the base polymer's mechanical properties. This new design also promotes better electrochemical interfaces with electrodes, a significant advancement over traditional BPEs. In this study, we further enhance the performance and processability of such hydrated polymer electrolytes by incorporating polylactic acid (PLA) as the base polymer and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as the salt. The electrolyte, prepared through solution casting and subsequent controlled hydration, consistently remains an amorphous solid solution in both dry and hydrated states, as confirmed by DSC, XRD, and FTIR analyses. Our tests on ionic conductivity and mechanical properties reveal that adding water to the polymer electrolyte substantially increases ionic conductivity while retaining mechanical properties. A specific composition demonstrated a remarkable increase in ionic conductivity coupled with superior toughness surpassing the base polymer. Furthermore, we successfully fabricated and tested structural supercapacitor devices made of composites of carbon fibers and these new electrolytes. The prototypes presented enhanced toughness with significant energy storage performance, demonstrating their vast application potential due to their outstanding multifunctionality. 

Disulfide bonds are ubiquitous molecular motifs that influence the tertiary structure and biological functions of many proteins. Yet, it is well known that the disulfide bond is photolabile when exposed to ultraviolet C (UVC) radiation. The deep-UV–induced S─S bond fragmentation kinetics on very fast timescales are especially pivotal to fully understand the photostability and photodamage repair mechanisms in proteins. In 1,2-dithiane, the smallest saturated cyclic molecule that mimics biologically active species with S─S bonds, we investigate the photochemistry upon 200-nm excitation by femtosecond time-resolved x-ray scattering in the gas phase using an x-ray free electron laser. In the femtosecond time domain, we find a very fast reaction that generates molecular fragments with one and two sulfur atoms. On picosecond and nanosecond timescales, a complex network of reactions unfolds that, ultimately, completes the sulfur dissociation from the parent molecule. 

The Strategic Partnership for Alignment of Community Engagement in STEM (SPACES) is a collaborative research effort under the National Science Foundation’s ADVANCE program. The overarching goal of SPACES is to build an inclusive academic culture to address intersectional gender-race-ethnicity inequities in Environmental Engineering (EnvE) via the application of evidence-based strategies for systemic change. The two main thrusts of the project are to address systemic problems that cause: (1) underrepresented minority women faculty (URMWF) experiences of isolation in and/or departures from STEM academia and (2) the devaluation of research conducted by URMWF, especially community-engaged research (CER). SPACES is a collaborative effort of faculty and administrators from 11 universities with four leading professional societies. SPACES is adapting evidence-based practices to support women’s intersectional identities and catalyze an attitudinal change among individuals and institutional leaders. This process involves the pursuit of 12 objectives crossing the micro, meso, and macro levels and is being operationalized through 11 activities. An overview of the motivations for this project and activities to date are provided in the paper. 

Abstract Stability issues in membrane-free coacervates have been addressed with coating strategies, but these approaches often compromise the permeability of the coacervate. Here we report a facile approach to maintain both stability and permeability using tannic acid and then demonstrate the value of this approach in enzyme-triggered drug release. First, we develop size-tunable coacervates via self-assembly of heparin glycosaminoglycan with tyrosine and arginine-based peptides. A thrombin-recognition site within the peptide building block results in heparin release upon thrombin proteolysis. Notably, polyphenols are integrated within the nano-coacervates to improve stability in biofluids. Phenolic crosslinking at the liquid-liquid interface enables nano-coacervates to maintain exceptional structural integrity across various environments. We discover a pivotal polyphenol threshold for preserving enzymatic activity alongside enhanced stability. The disassembly rate of the nano-coacervates increases as a function of thrombin activity, thus preventing a coagulation cascade. This polyphenol-based approach not only improves stability but also opens the way for applications in biomedicine, protease sensing, and bio-responsive drug delivery. 

Abstract We report noncovalent assemblies of iRGD peptides and methylene blue dyes via electrostatic and hydrophobic stacking. These resulting nanomaterials could bind to cancer cells, image them with photoacoustic signal, and then treat them via photodynamic therapy. We first assessed the optical properties and physical properties of the materials. We then evaluated their utility for live cell targeting, in vivo imaging, and in vivo photodynamic toxicity. We tuned the performance of iRGD by adding aspartic acid (DD) or tryptophan doublets (WW) to the peptide to promote electrostatic or hydrophobic stacking with methylene blue, respectively. The iRGD-DD led to 150-nm branched nanoparticles, but iRGD-WW produced 200-nm nano spheres. The branched particles had an absorbance peak that was redshifted to 720 nm suitable for photoacoustic signal. The nanospheres had a peak at 680 nm similar to monomeric methylene blue. Upon continuous irradiation, the nanospheres and branched nanoparticles led to a 116.62% and 94.82% increase in reactive oxygen species in SKOV-3 cells relative to free methylene blue at isomolar concentrations suggesting photodynamic toxicity. Targeted uptake was validated via competitive inhibition. Finally, we used in vivo bioluminescent signal to monitor tumor burden and the effect of for photodynamic therapy: The nanospheres had little impact versus controls (p = 0.089), but the branched nanoparticles slowed SKOV-3 tumor burden by 75.9% (p < 0.05). 

Abstract Structural supercapacitors that simultaneously bear mechanical loads and store electrical energy have exciting potential for enhancing the efficiency of various mobile systems. However, a significant hurdle in developing practical structural supercapacitors is the inherent trade‐off between their mechanical properties and electrochemical capabilities, particularly within their electrolytes. This study demonstrates a tough polymer electrolyte with enhanced multifunctionality made through the controlled hydration of a solid polymer electrolyte with poly(lactic acid) (PLA) and lithium salts. Characterization via differential scanning calorimetry, X‐ray diffraction, and Fourier transform infrared spectroscopy confirms the consistent amorphous solid solution phase in varying salt concentrations, whether dried or hydrated. Electrochemical tests and tensile tests are performed to evaluate the ionic conductivity and mechanical properties of these electrolytes. The results indicate that the strategic incorporation of water in the polymer electrolyte significantly enhances the ionic conductivity while preserving its mechanical properties. A specific composition demonstrated a remarkable increase in ionic conductivity (3.11 µS cm⁻¹) coupled with superior toughness (15.4 MJ m⁻³), significantly surpassing the base polymer. These findings open new horizons for integrating electrochemical functionality into structural polymers without compromising their mechanical properties. Additionally, the paper reports the successful fabrication and testing of structural supercapacitor prototypes combining carbon fibers with fabricated electrolytes, showcasing their potential for diverse applications.