@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={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{turner_senevirathne_kilgour_mcart_biggs_menegatti_daniele_2021, title={Ultrasound-Powered Implants: A Critical Review of Piezoelectric Material Selection and Applications}, volume={7}, ISSN={["2192-2659"]}, DOI={10.1002/adhm.202100986}, abstractNote={Ultrasound-powered implants (UPIs) represent cutting edge power sources for implantable medical devices (IMDs), as their powering strategy allows for extended functional lifetime, decreased size, increased implant depth, and improved biocompatibility. IMDs are limited by their reliance on batteries. While batteries proved a stable power supply, batteries feature relatively large sizes, limited life spans, and toxic material compositions. Accordingly, energy harvesting and wireless power transfer (WPT) strategies are attracting increasing attention by researchers as alternative reliable power sources. Piezoelectric energy scavenging has shown promise for low power applications. However, energy scavenging devices need be located near sources of movement, and the power stream may suffer from occasional interruptions. WPT overcomes such challenges by more stable, on-demand power to IMDs. Among the various forms of WPT, ultrasound powering offers distinct advantages such as low tissue-mediated attenuation, a higher approved safe dose (720 mW cm−2), and improved efficiency at smaller device sizes. This study presents and discusses the state-of-the-art in UPIs by reviewing piezoelectric materials and harvesting devices including lead-based inorganic, lead-free inorganic, and organic polymers. A comparative discussion is also presented of the functional material properties, architecture, and performance metrics, together with an overview of the applications where UPIs are being deployed.}, journal={ADVANCED HEALTHCARE MATERIALS}, author={Turner, Brendan L. and Senevirathne, Seedevi and Kilgour, Katie and McArt, Darragh and Biggs, Manus and Menegatti, Stefano and Daniele, Michael A.}, year={2021}, month={Jul} }
 @article{turner_kilgour_stine_daniele_menegatti_2020, title={Dual-Affinity Ratiometric Quenching (DARQ) Assay for the Quantification of Therapeutic Antibodies in CHO-S Cell Culture Fluids}, volume={92}, ISSN={["1520-6882"]}, DOI={10.1021/acs.analchem.0c04269}, abstractNote={More than 100 monoclonal antibodies (mAbs) are in industrial and clinical development to treat myriad diseases. Accurate quantification of mAbs in complex media, derived from industrial and patient samples, is vital to determine production efficiency or pharmacokinetic properties. To date, mAb quantification requires time and labor-intensive assays. Herein, we report a novel dual-affinity ratiometric quenching (DARQ) assay, which combines selective biorecognition and quenching of fluorescence signals for rapid and sensitive quantification of therapeutic monoclonal antibodies (mAbs). The reported assay relies on the affinity complexation of the target mAb by the corresponding antigens and Protein L (PrL, which targets the Fab region of the antibody), respectively, labeled with fluorescein and rhodamine. Within the affinity complex, the mAb acts as a scaffold framing the labeled affinity tags (PrL and antigen) in a molecular proximity that results in ratiometric quenching of their fluorescence emission. Notably, the decrease in fluorescence emission intensity is linearly dependent upon mAb concentration in solution. Control experiments conducted with one affinity tag only, two tags labeled with equal fluorophores, or two tags labeled with fluorophores of discrete absorbance and emission bands exhibited significantly reduced effect. The assay was evaluated in noncompetitive (pure mAb) and competitive conditions (mAb in a Chinese Hamster Ovary (CHO) cell culture harvest). The DARQ assay is highly reproducible (coefficient of variation ∼0.8-0.7%) and rapid (5 min), and its sensitivity (∼0.2-0.5 ng·mL-1), limit of detection (75-119 ng·mL-1), and dynamic range (300-1600 ng·mL-1) are independent of the presence of CHO host cell proteins.}, number={24}, journal={ANALYTICAL CHEMISTRY}, author={Turner, Brendan L. and Kilgour, Katie M. and Stine, Sydney J. and Daniele, Michael and Menegatti, Stefano}, year={2020}, month={Dec}, pages={16274–16283} }
 @article{yuen_pozdin_young_turner_giles_naciri_trammell_charles_stenger_daniele_2020, title={Perylene-diimide-based n-type semiconductors with enhanced air and temperature stable photoconductor and transistor properties}, volume={174}, ISSN={["1873-3743"]}, DOI={10.1016/j.dyepig.2019.108014}, abstractNote={We report the synthesis and characterization of highly air and temperature stable, solution-processed, n-type organic semiconductors: a perylene-diimide monomer and a perylene-diimide-based pendant polymer. When integrated into a transistor structure, both materials possess pure n-type transport with mobility as high as 10−5 cm2 V−1 s−1 for the polymer. The organic semiconductors exhibit good photoconductor properties, with photocurrent to dark current ratios of up to 103 for the monomer, despite its lower FET mobility. The differences in transistor and photoconductor properties suggest different applications for each material. Both materials can be processed in air, and their transport properties have good air stability, improving with annealing even up to 200 °C in air. It is notable that such air-stable photoconductivity and transport properties have rarely been reported for n-type organic semiconductors before, as most n-type organic semiconductors are not stable in air. Hence, these materials may have potential in a wide range of applications.}, journal={DYES AND PIGMENTS}, author={Yuen, Jonathan D. and Pozdin, Vladimir A. and Young, Ashlyn T. and Turner, Brendan L. and Giles, Ian D. and Naciri, Jawad and Trammell, Scott A. and Charles, Paul T. and Stenger, David A. and Daniele, Michael A.}, year={2020}, month={Mar} }