@article{turner_twiddy_wilkins_ramesh_kilgour_domingos_nasrallah_menegatti_daniele_2023, title={Biodegradable elastomeric circuit boards from citric acid-based polyesters}, volume={7}, ISSN={["2397-4621"]}, DOI={10.1038/s41528-023-00258-z}, abstractNote={Abstract Recyclable and biodegradable microelectronics, i.e., “green” electronics, are emerging as a viable solution to the global challenge of electronic waste. Specifically, flexible circuit boards represent a prime target for materials development and increasing the utility of green electronics in biomedical applications. Circuit board substrates and packaging are good dielectrics, mechanically and thermally robust, and are compatible with microfabrication processes. Poly(octamethylene maleate (anhydride) citrate) (POMaC) – a citric acid-based elastomer with tunable degradation and mechanical properties – presents a promising alternative for circuit board substrates and packaging. Here, we report the characterization of Elastomeric Circuit Boards (ECBs). Synthesis and processing conditions were optimized to achieve desired degradation and mechanical properties for production of stretchable circuits. ECB traces were characterized and exhibited sheet resistance of 0.599 Ω cm −2 , crosstalk distance of <0.6 mm, and exhibited stable 0% strain resistances after 1000 strain cycles to 20%. Fabrication of single layer and encapsulated ECBs was demonstrated.}, number={1}, journal={NPJ FLEXIBLE ELECTRONICS}, author={Turner, Brendan L. and Twiddy, Jack and Wilkins, Michael D. and Ramesh, Srivatsan and Kilgour, Katie M. and Domingos, Eleo and Nasrallah, Olivia and Menegatti, Stefano and Daniele, Michael A.}, year={2023}, month={Jun} }
 @article{ramesh_davis_roros_zhou_he_gao_menegatti_khan_genzer_2022, title={Nonwoven Membranes with Infrared Light-Controlled Permeability}, volume={9}, ISSN={["1944-8252"]}, DOI={10.1021/acsami.2c13280}, abstractNote={This study presents the development of the first composite nonwoven fiber mats (NWFs) with infrared light-controlled permeability. The membranes were prepared by coating polypropylene NWFs with a photothermal layer of poly(N-isopropylacrylamide) (PNIPAm)-based microgels impregnated with graphene oxide nanoparticles (GONPs). This design enables "photothermal smart-gating" using light dosage as remote control of the membrane's permeability to electrolytes. Upon exposure to infrared light, the GONPs trigger a rapid local increase in temperature, which contracts the PNIPAm-based microgels lodged in the pore space of the NWFs. The contraction of the microgels can be reverted by cooling from the surrounding aqueous environment. The efficient conversion of infrared light into localized heat by GONPs coupled with the phase transition of the microgels above the lower critical solution temperature (LCST) of PNIPAm provide effective control over the effective porosity, and thus the permeability, of the membrane. The material design parameters, namely the monomer composition of the microgels and the GONP-to-microgel ratio, enable tuning the permeability shift in response to IR light; control NWFs coated with GONP-free microgels displayed thermal responsiveness only, whereas native NWFs showed no smart-gating behavior at all. This technology shows potential toward processing temperature-sensitive bioactive ingredients or remote-controlled bioreactors.}, journal={ACS APPLIED MATERIALS & INTERFACES}, author={Ramesh, Srivatsan and Davis, Jack and Roros, Alexandra and Zhou, Chuanzhen and He, Nanfei and Gao, Wei and Menegatti, Stefano and Khan, Saad and Genzer, Jan}, year={2022}, month={Sep} }
 @article{barbieri_cutright_ramesh_khan_efimenko_genzer_menegatti_2022, title={Potent Antibacterial Composite Nonwovens Functionalized with Bioactive Peptides and Polymers}, volume={8}, ISSN={["2196-7350"]}, url={https://doi.org/10.1002/admi.202201061}, DOI={10.1002/admi.202201061}, abstractNote={This study presents a set of strategies for producing potent antibacterial fabrics by functionalizing nonwoven fabrics (NWFs) with antimicrobial peptides and polymers (AMPs). The incorporation of AMPs is initially optimized on 2D substrates by evaluating conjugation on a poly(maleic anhydride) copolymer coating versus adsorption on polycationic/anionic films and microgels. The evaluation of the resulting surfaces against S. aureus and E. coli highlights the superior antibacterial activity of poly‐ionic films loaded with daptomycin and polymyxin B as well as microgels featuring controlled release of bacitracin and polymyxin B. These formulations are translated onto spun‐bond polypropylene and poly(ethylene terephthalate) NWFs. The poly‐ionic coatings are either covalently anchored or physically adsorbed onto the surface of the fibers, while the microgels and antibacterial polymers are adsorbed and photo‐crosslinked thereon using a ultraviolet (UV)‐crosslinkable benzophenone‐based polymer. Selected formulations loaded with bacitracin and polymyxin B afford a 105‐fold reduction of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) in artificial sweat, respectively, on par with commercial antibacterial NWFs. The proposed antibacterial fabric, however, outperforms its commercial counterparts in terms of biocompatibility, showing virtually no adverse effect on human epidermal keratinocytes. Collectively, these results demonstrate affordable and scalable routes for developing antimicrobial NWFs that efficiently eliminate resilient pathogenic bacteria.}, journal={ADVANCED MATERIALS INTERFACES}, author={Barbieri, Eduardo and Cutright, Camden C. and Ramesh, Srivatsan and Khan, Saad A. and Efimenko, Kirill and Genzer, Jan and Menegatti, Stefano}, year={2022}, month={Aug} }
 @misc{ramesh_khan_park_ford_menegatti_genzer_2022, title={Self-healing and repair of fabrics: A comprehensive review of the application toolkit}, volume={54}, ISSN={["1873-4103"]}, DOI={10.1016/j.mattod.2021.11.016}, abstractNote={Self-healing fabrics respond to chemical and physical damage by restoring functional, structural, and morphological features. We present a comprehensive review of textile hybrids or composites capable of self-healing and repairing fabrics against damages across the micro- (µm), meso- (µm – mm), and macro-scale (>mm). The reviewed literature is organized in three sections presenting (i) the chemistry and fabrication principles of designing self-healing fabrics against increasing size scales of repair, (ii) stimuli-driven and autonomous healing, and (iii) the methods to characterize the recovery of wettability, barrier, morphological, mechanical, and other properties. The discussion of mainstream methods for developing self-healing fabrics focuses on coatings, composites, and specialized fabrication techniques required as the damage size grows from µm to mm to >mm. The section on stimuli-driven repair and autonomous recovery discusses the time scales associated with different damage repair, showing how external stimuli provide a higher driving force towards healing and accelerate material restoration than autonomous recovery. Finally, an array of optical, mechanical, and functional characterization techniques is discussed to evaluate the recovery yield and understand the repair mechanisms of the various fabrics. This review demonstrates the virtually limitless uses of next-generation self-healing systems, from separations to protective clothing, anti-fouling, and self-cleaning.}, journal={MATERIALS TODAY}, author={Ramesh, Srivatsan and Khan, Saad and Park, Yaewon and Ford, Ericka and Menegatti, Stefano and Genzer, Jan}, year={2022}, month={Apr}, pages={90–109} }
 @article{ramesh_davis_roros_eiben_fabiani_smith_reynolds_pourdeyhimi_khan_genzer_et al._2021, title={Dual-Responsive Microgels for Structural Repair and Recovery of Nonwoven Membranes for Liquid Filtration}, volume={3}, ISSN={["2637-6105"]}, url={https://doi.org/10.1021/acsapm.0c01360}, DOI={10.1021/acsapm.0c01360}, abstractNote={This study presents dual-responsive colloidal microgels to repair nonwoven fiber mats (NWFs) and recover their native morphological and functional properties. The formulation comprises poly(N-isopr...}, number={3}, journal={ACS APPLIED POLYMER MATERIALS}, publisher={American Chemical Society (ACS)}, author={Ramesh, Srivatsan and Davis, Jack and Roros, Alexandra and Eiben, Justin and Fabiani, Thomas and Smith, Ryan and Reynolds, Lewis and Pourdeyhimi, Behnam and Khan, Saad and Genzer, Jan and et al.}, year={2021}, month={Mar}, pages={1508–1517} }
 @article{turner_ramesh_menegatti_daniele_2021, title={Resorbable elastomers for implantable medical devices: highlights and applications}, volume={12}, ISSN={["1097-0126"]}, DOI={10.1002/pi.6349}, abstractNote={Abstract Resorbable elastomers are an emerging class of materials required for transient implantable medical devices (IMDs), as their tissue‐matching mechanical properties decrease the risks associated with implant removal and promote functional tissue integration. Traditional materials employed in IMDs are typically much more rigid than native tissue, which leads to increased foreign body response and tissue irritation, and must be removed at the end of life of the implant, thus increasing the risk to patients. Resorbable elastomeric biomaterials support efficiently all the functions of substrate/encapsulant, dielectric, semiconductors and conductors that are needed in IMDs, while offering beneficial mechanical properties and a programed degradation that circumvents the need for surgical removal. This mini‐review presents the chemical characteristics, material properties and applications as IMD substrates of three resorbable elastomer families: polyurethane, poly(glycerol sebacate) and poly(diol citrate). Finally, some challenges and future directions on the pathway to biomedical adoption of resorbable elastomeric biomaterials are discussed including safety, processing conditions and critical development steps for conductive and dielectric elastomers. © 2021 Society of Industrial Chemistry.}, journal={POLYMER INTERNATIONAL}, author={Turner, Brendan and Ramesh, Srivatsan and Menegatti, Stefano and Daniele, Michael}, year={2021}, month={Dec} }
 @article{cutright_harris_ramesh_khan_genzer_menegatti_2021, title={Surface-Bound Microgels for Separation, Sensing, and Biomedical Applications}, volume={31}, ISSN={["1616-3028"]}, url={https://doi.org/10.1002/adfm.202104164}, DOI={10.1002/adfm.202104164}, abstractNote={This study presents a comprehensive survey of microgel‐coated materials and their functional behavior, describing the complex interplay between the physicochemical and mechanical properties of the microgels and the chemical and morphological features of substrates. The cited literature is articulated in four main sections: i) properties of 2D and 3D substrates, ii) synthesis, modification, and characterization of the microgels, iii) deposition techniques and surface patterning, and iv) application of microgel‐coated surfaces focusing on separations, sensing, and biomedical applications. Each section discusses – by way of principles and examples – how the various design parameters work in concert to deliver functionality to the composite systems. The case studies presented herein are viewed through a multi‐scale lens. At the molecular level, the surface chemistry and the monomer make‐up of the microgels endow responsiveness to environmental and artificial physical and chemical cues. At the micro‐scale, the response effects shifts in size, mechanical, and optical properties, and affinity towards species in the surrounding liquid medium, ranging from small molecules to cells. These phenomena culminate at the macro‐scale in measurable, reversible, and reproducible effects, aiming in a myriad of directions, from lab‐scale to industrial applications.}, number={47}, journal={ADVANCED FUNCTIONAL MATERIALS}, publisher={Wiley}, author={Cutright, Camden C. and Harris, Jacob L. and Ramesh, Srivatsan and Khan, Saad A. and Genzer, Jan and Menegatti, Stefano}, year={2021}, month={Aug} }
 @article{smith_fabiani_wang_ramesh_khan_santiso_silva_gorman_menegatti_2020, title={Exploring the physicochemical and morphological properties of peptide‐hybridized dendrimers (
            DendriPeps
            ) and their aggregates}, volume={58}, ISSN={2642-4150 2642-4169}, url={http://dx.doi.org/10.1002/pol.20200277}, DOI={10.1002/pol.20200277}, abstractNote={Abstract This article presents an integrated experimental and computational study of DendriPeps, a novel class of dendrimers featuring a polyamidoamine (PAMAM) backbone hybridized with peptide segments. Hydroxyl‐terminated Generation 2 (G.2) DendriPeps, comprising either four lysines (Lys) or four glutamic acids (Glu), and G.3 DendriPeps, comprising 8 Lys or 8 Glu, were first characterized in terms of hydrodynamic radius ( R h ) and ζ‐potential in aqueous solution. Unlike PAMAM dendrimers, DendriPeps form aggregates with R h between 60 and 980 nm and ζ‐potential between −130 and 80 mV despite their strong net charge. Upon application of shear, all aggregates disassemble into monomeric DendriPeps ( R h ~ 1–3 nm), but reform rapidly as shear is removed. Rheological characterization confirmed that DendriPep aggregates are disrupted by mild shear, but reform reversibly. Molecular dynamics simulations, informed by titrimetry, suggest that DendriPep aggregation derives from their multipolar structure and ability to rearrange the intermolecular/intramolecular pairing of titratable moieties at different pH values.}, number={16}, journal={Journal of Polymer Science}, publisher={Wiley}, author={Smith, Ryan J. and Fabiani, Thomas and Wang, Siyao and Ramesh, Srivatsan and Khan, Saad and Santiso, Erik and Silva, Fernando Luis Barroso and Gorman, Christopher and Menegatti, Stefano}, year={2020}, month={Jul}, pages={2234–2247} }
 @article{schneible_shi_young_ramesh_he_dowdey_dubnansky_libya_gao_santiso_et al._2020, title={Modified gaphene oxide (GO) particles in peptide hydrogels: a hybrid system enabling scheduled delivery of synergistic combinations of chemotherapeutics}, volume={8}, ISSN={["2050-7518"]}, DOI={10.1039/d0tb00064g}, abstractNote={The scheduled delivery of synergistic drug combinations is increasingly recognized as highly effective against advanced solid tumors. Of particular interest are composite systems that release a sequence of drugs with defined kinetics and molar ratios to enhance therapeutic effect, while minimizing the dose to patients. In this work, we developed a homogeneous composite comprising modified graphene oxide (GO) nanoparticles embedded in a Max8 peptide hydrogel, which provides controlled kinetics and molar ratios of release of doxorubicin (DOX) and gemcitabine (GEM). First, modified GO nanoparticles (tGO) were designed to afford high DOX loading and sustained release (18.9% over 72 h and 31.4% over 4 weeks). Molecular dynamics simulations were utilized to model the mechanism of DOX loading as a function of surface modification. In parallel, a Max8 hydrogel was developed to release GEM with faster kinetics and achieve a 10-fold molar ratio to DOX. The selected DOX/tGO nanoparticles were suspended in a GEM/Max8 hydrogel matrix, and the resulting composite was tested against a triple negative breast cancer cell line, MDA-MB-231. Notably, the composite formulation afforded a combination index of 0.093 ± 0.001, indicating a much stronger synergism compared to the DOX-GEM combination co-administered in solution (CI = 0.396 ± 0.034).}, number={17}, journal={JOURNAL OF MATERIALS CHEMISTRY B}, author={Schneible, John D. and Shi, Kaihang and Young, Ashlyn T. and Ramesh, Srivatsan and He, Nanfei and Dowdey, Clay E. and Dubnansky, Jean Marie and Libya, Radina L. and Gao, Wei and Santiso, Erik and et al.}, year={2020}, month={May}, pages={3852–3868} }