@article{wells_ciftci_peddinti_ghiladi_vediyappan_spontak_govind_2023, title={Preventing the spread of life-threatening gastrointestinal microbes on the surface of a continuously self-disinfecting block polymer}, volume={652}, ISSN={["1095-7103"]}, DOI={10.1016/j.jcis.2023.08.088}, abstractNote={Highly persistent, drug-resistant and transmissible healthcare pathogens such as Clostridioides difficile (C. difficile) and Candida auris (C. auris) are responsible for causing antibiotic-associated fatal diarrhea and invasive candidiasis, respectively. In this study, we demonstrate that these potentially lethal gastrointestinal microbes can be rapidly inactivated on the solid surface of a self-disinfecting anionic block polymer that inherently generates a water surface layer that is highly acidic (pH < 1) upon hydration. Due to thermodynamic incompatibility between its chemical sequences, the polymer spontaneously self-organizes into a nanostructure that enables proton migration from the interior of a film to the surface via contiguous nanoscale hydrophilic channels, as discerned here by scanning electron and atomic force microscopies, as well as X-ray photoelectron spectroscopy. Here, we report that two strains of C. difficile in the vegetative state and two species of Candida, Candida albicans (C. albicans) and C. auris, are, in most cases, inactivated to the limit of minimum detection. Corresponding electron and optical microscopy images reveal that, upon exposure to the hydrated polymer, the outer microbial membranes display evidence of damage and intracellular material is expelled. Combined with our previous studies of rapid bacterial and viral inactivation, these antimicrobial results are highly encouraging and, if translatable to clinical conditions in the form of self-standing polymer films or coatings, are expected to benefit the welfare of patients in healthcare facilities by continuously preventing the spread of these potentially dangerous microbes.}, journal={JOURNAL OF COLLOID AND INTERFACE SCIENCE}, author={Wells, Kacie M. and Ciftci, Yusuf and Peddinti, Bharadwaja S. T. and Ghiladi, Reza A. and Vediyappan, Govindsamy and Spontak, Richard J. and Govind, Revathi}, year={2023}, month={Dec}, pages={718–726} }
 @article{peddinti_downs_yan_smith_ghiladi_mhetar_tocchetto_griffiths_scholle_spontak_2021, title={Rapid and Repetitive Inactivation of SARS-CoV-2 and Human Coronavirus on Self-Disinfecting Anionic Polymers}, volume={8}, ISSN={["2198-3844"]}, DOI={10.1002/advs.202003503}, abstractNote={Abstract}, number={11}, journal={ADVANCED SCIENCE}, author={Peddinti, Bharadwaja S. T. and Downs, Sierra N. and Yan, Jiaqi and Smith, Steven D. and Ghiladi, Reza A. and Mhetar, Vijay and Tocchetto, Roger and Griffiths, Anthony and Scholle, Frank and Spontak, Richard J.}, year={2021}, month={Jun} }
 @article{ghareeb_peddinti_kisthardt_scholle_spontak_ghiladi_2021, title={Toward Universal Photodynamic Coatings for Infection Control}, volume={8}, ISSN={["2296-858X"]}, DOI={10.3389/fmed.2021.657837}, abstractNote={The dual threats posed by the COVID-19 pandemic and hospital-acquired infections (HAIs) have emphasized the urgent need for self-disinfecting materials for infection control. Despite their highly potent antimicrobial activity, the adoption of photoactive materials to reduce infection transmission in hospitals and related healthcare facilities has been severely hampered by the lack of scalable and cost-effective manufacturing, in which case high-volume production methods for fabricating aPDI-based materials are needed. To address this issue here, we examined the antimicrobial efficacy of a simple bicomponent spray coating composed of the commercially-available UV-photocrosslinkable polymer N-methyl-4(4'-formyl-styryl)pyridinium methosulfate acetal poly(vinyl alcohol) (SbQ-PVA) and one of three aPDI photosensitizers (PSs): zinc-tetra(4-N-methylpyridyl)porphine (ZnTMPyP4+), methylene blue (MB), and Rose Bengal (RB). We applied these photodynamic coatings, collectively termed SbQ-PVA/PS, to a variety of commercially available materials. Scanning electron microscopy (SEM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) confirmed the successful application of the coatings, while inductively coupled plasma-optical emission spectroscopy (ICP-OES) revealed a photosensitizer loading of 0.09-0.78 nmol PS/mg material. The antimicrobial efficacy of the coated materials was evaluated against methicillin-susceptible Staphylococcus aureus ATCC-29213 and human coronavirus strain HCoV-229E. Upon illumination with visible light (60 min, 400-700 nm, 65 ± 5 mW/cm2), the coated materials inactivated S. aureus by 97-99.999% and HCoV-229E by 92-99.999%, depending on the material and PS employed. Photobleaching studies employing HCoV-229E demonstrated detection limit inactivation (99.999%) even after exposure for 4 weeks to indoor ambient room lighting. Taken together, these results demonstrate the potential for photodynamic SbQ-PVA/PS coatings to be universally applied to a wide range of materials for effectively reducing pathogen transmission.}, journal={FRONTIERS IN MEDICINE}, author={Ghareeb, C. Roland and Peddinti, Bharadwaja S. T. and Kisthardt, Samantha C. and Scholle, Frank and Spontak, Richard J. and Ghiladi, Reza A.}, year={2021}, month={Jul} }
 @article{peddinti_morales-gagnon_pourdeyhimi_scholle_spontak_ghiladi_2020, title={Photodynamic Coatings on Polymer Microfibers for Pathogen Inactivation: Effects of Application Method and Composition}, volume={13}, ISSN={1944-8244 1944-8252}, url={http://dx.doi.org/10.1021/acsami.0c16953}, DOI={10.1021/acsami.0c16953}, abstractNote={A substantial increase in the risk of hospital-acquired infections (HAIs) has greatly impacted the global healthcare industry. Harmful pathogens adhere to a variety of surfaces and infect personnel on contact, thereby promoting transmission to new hosts. This is particularly worrisome in the case of antibiotic-resistant pathogens, which constitute a growing threat to human health worldwide and require new preventative routes of disinfection. In this study, we have incorporated different loading levels of a porphyrin photosensitizer capable of generating reactive singlet oxygen in the presence of O2 and visible light in a water-soluble, photo-cross-linkable polymer coating, which was subsequently deposited on polymer microfibers. Two different application methods are considered, and the morphological and chemical characteristics of these coated fibers are analyzed to detect the presence of the coating and photosensitizer. To discern the efficacy of the fibers against pathogenic bacteria, photodynamic inactivation has been performed on two different bacterial strains, Staphylococcus aureus and antibiotic-resistant Escherichia coli, with population reductions of >99.9999 and 99.6%, respectively, after exposure to visible light for 1 h. In response to the current COVID-19 pandemic, we also confirm that these coated fibers can inactivate a human common cold coronavirus serving as a surrogate for the SARS-CoV-2 virus.}, number={1}, journal={ACS Applied Materials & Interfaces}, publisher={American Chemical Society (ACS)}, author={Peddinti, Bharadwaja S. T. and Morales-Gagnon, Nicolas and Pourdeyhimi, Behnam and Scholle, Frank and Spontak, Richard J. and Ghiladi, Reza A.}, year={2020}, month={Dec}, pages={155–163} }