@article{schuchard_pawar_anderson_pourdeyhimi_shirwaiker_2022, title={Multiphase CFD Modeling and Experimental Validation of Polymer and Attenuating Air Jet Interactions in Nonwoven Annular Melt Blowing}, volume={61}, ISSN={["0888-5885"]}, DOI={10.1021/acs.iecr.2c01710}, abstractNote={In annular melt blowing, fiber formation is achieved by accelerating a molten polymer via drag forces imparted by high velocity air that attenuates the polymer jet diameter. The interactions at the polymer-air interface, which govern the motion of the jets and impact the resulting fiber characteristics, are important but not well understood yet. This work details the development and validation of a multiphase computational fluid dynamics (CFD) model to investigate these interactions and the effects of three key melt blowing process parameters (polymer viscosity and throughput, and air velocity) on two critical fiber attributes - whipping instability and fiber diameter. Simulation results highlighted that whipping instability was driven by the polymer-air velocity differential, and the fiber diameter was primarily modulated by polymer throughput and air velocity. The CFD model was validated by modulating the polymer and air throughputs and analyzing the fiber diameter experimentally. Empirical results showed good agreement between fabricated and model-estimated fiber diameters, especially at lower air velocities. An additional CFD simulation performed using a melt blowing nozzle geometry and process parameters described in literature also confirmed good correlation between model estimates and literature empirical data.}, number={37}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={Schuchard, Karl G. and Pawar, Advay and Anderson, Bruce and Pourdeyhimi, Behnam and Shirwaiker, Rohan A.}, year={2022}, month={Sep}, pages={13962–13971} }
 @article{schuchard_joijode_willard_anderson_grondin_pourdeyhimi_shirwaiker_2021, title={Fabrication of drug-loaded ultrafine polymer fibers via solution blowing and their drug release kinetics}, volume={53}, ISSN={["2351-9789"]}, DOI={10.1016/j.promfg.2021.06.017}, abstractNote={Biocompatible polymer fibers have garnered significant interest due to their unique properties. Applications range from absorbent media to tissue engineering and drug delivery products. Many manufacturing processes produce such fibers, but a gap exists in highly scalable processes for fibers loaded with thermolabile additives like pharmaceuticals. This study investigates preliminary process-structure-function relationships of solution blown poly(ethylene oxide) fibers loaded with doxycycline, a drug that has demonstrated antibiotic, anti-inflammatory, and anti-tumoral properties. After parameter screening, a factorial experiment mapped the solution blowing design space with a multi-nozzle apparatus. A 1 mm-thick mat was fabricated comprising doxycycline loaded polymer fibers with a mean diameter of 552 ± 200 nm. Study of release kinetics showed the doxycycline released with a significant burst effect over approximately 1 minute. This study highlights solution blowing as a scalable manufacturing platform for fabricating poly(ethylene oxide) fibers loaded with this impactful drug.}, journal={49TH SME NORTH AMERICAN MANUFACTURING RESEARCH CONFERENCE (NAMRC 49, 2021)}, author={Schuchard, Karl and Joijode, Abhay and Willard, Vincent P. and Anderson, Bruce and Grondin, Pierre and Pourdeyhimi, Behnam and Shirwaiker, Rohan}, year={2021}, pages={128–135} }
 @article{nordberg_huebner_schuchard_mellor_shirwaiker_loboa_spang_2021, title={The evaluation of a multiphasic 3D-bioplotted scaffold seeded with adipose derived stem cells to repair osteochondral defects in a porcine model}, volume={6}, ISSN={["1552-4981"]}, DOI={10.1002/jbm.b.34886}, abstractNote={AbstractThere is a need for the development of effective treatments for focal articular cartilage injuries. We previously developed a multiphasic 3D‐bioplotted osteochondral scaffold design that can drive site‐specific tissue formation when seeded with adipose‐derived stem cells (ASC). The objective of this study was to evaluate this scaffold in a large animal model. Osteochondral defects were generated in the trochlear groove of Yucatan minipigs and repaired with scaffolds that either contained or lacked an electrospun tidemark and were either unseeded or seeded with ASC. Implants were monitored via computed tomography (CT) over the course of 4 months of in vivo implantation and compared to both open lesions and autologous explants. ICRS II evaluation indicated that defects with ASC‐seeded scaffolds had healing that most closely resembled the aulogous explant. Scaffold‐facilitated subchondral bone repair mimicked the structure of native bone tissue, but cartilage matrix staining was not apparent within the scaffold. The open lesions had the highest volumetric infill detected using CT analysis (p < 0.05), but the repair tissue was largely disorganized. The acellular scaffold without a tidemark had significantly more volumetric filling than either the acellular or ASC seeded groups containing a tidemark (p < 0.05), suggesting that the tidemark limited cell infiltration into the cartilage portion of the scaffold. Overall, scaffold groups repaired the defect more successfully than an open lesion but achieved limited repair in the cartilage region. With further optimization, this approach holds potential to treat focal cartilage lesions in a highly personalized manner using a human patient's own ASC cells.}, journal={JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS}, author={Nordberg, Rachel C. and Huebner, Pedro and Schuchard, Karl G. and Mellor, Liliana F. and Shirwaiker, Rohan A. and Loboa, Elizabeth G. and Spang, Jeffery T.}, year={2021}, month={Jun} }
 @article{shirwaiker_fisher_anderson_schuchard_warren_maze_grondin_ligler_pourdeyhimi_2020, title={High-Throughput Manufacture of 3D Fiber Scaffolds for Regenerative Medicine}, volume={26}, ISSN={["1937-3392"]}, DOI={10.1089/ten.tec.2020.0098}, abstractNote={Engineered scaffolds used to regenerate mammalian tissues should recapitulate the underlying fibrous architecture of native tissue to achieve comparable function. Current fibrous scaffold fabrication processes, such as electrospinning and three-dimensional (3D) printing, possess application-specific advantages, but they are limited either by achievable fiber sizes and pore resolution, processing efficiency, or architectural control in three dimensions. As such, a gap exists in efficiently producing clinically relevant, anatomically sized scaffolds comprising fibers in the 1–100 μm range that are highly organized. This study introduces a new high-throughput, additive fibrous scaffold fabrication process, designated in this study as 3D melt blowing (3DMB). The 3DMB system described in this study is modified from larger nonwovens manufacturing machinery to accommodate the lower volume, high-cost polymers used for tissue engineering and implantable biomedical devices and has a fiber collection component that uses adaptable robotics to create scaffolds with predetermined geometries. The fundamental process principles, system design, and key parameters are described, and two examples of the capabilities to create scaffolds for biomedical engineering applications are demonstrated. Impact statement Three-dimensional melt blowing (3DMB) is a new, high-throughput, additive manufacturing process to produce scaffolds composed of highly organized fibers in the anatomically relevant 1–100 μm range. Unlike conventional melt-blowing systems, the 3DMB process is configured for efficient use with the relatively expensive polymers necessary for biomedical applications, decreasing the required amounts of material for processing while achieving high throughputs compared with 3D printing or electrospinning. The 3DMB is demonstrated to make scaffolds composed of multiple fiber materials and organized into complex shapes, including those typical of human body parts.}, number={7}, journal={TISSUE ENGINEERING PART C-METHODS}, author={Shirwaiker, Rohan A. and Fisher, Matthew B. and Anderson, Bruce and Schuchard, Karl G. and Warren, Paul B. and Maze, Benoit and Grondin, Pierre and Ligler, Frances S. and Pourdeyhimi, Behnam}, year={2020}, month={Jul}, pages={364–374} }
 @misc{chansoria_schuchard_shirwaiker_2021, title={Process hybridization schemes for multiscale engineered tissue biofabrication}, volume={13}, ISSN={["1939-0041"]}, url={http://dx.doi.org/10.1002/wnan.1673}, DOI={10.1002/wnan.1673}, abstractNote={AbstractRecapitulation of multiscale structure–function properties of cells, cell‐secreted extracellular matrix, and 3D architecture of natural tissues is central to engineering biomimetic tissue substitutes. Toward achieving biomimicry, a variety of biofabrication processes have been developed, which can be broadly classified into five categories—fiber and fabric formation, additive manufacturing, surface modification, remote fields, and other notable processes—each with specific advantages and limitations. The majority of biofabrication literature has focused on using a single process at a time, which often limits the range of tissues that could be created with relevant features that span nano to macro scales. With multiscale biomimicry as the goal, development of hybrid biofabrication strategies that synergistically unite two or more processes to complement each other's strengths and limitations has been steadily increasing. This work discusses recent literature in this domain and attempts to equip the reader with the understanding of selecting appropriate processes that can harmonize toward creating engineered tissues with appropriate multiscale structure–function properties. Opportunities related to various hybridization schemes and a future outlook on scale‐up biofabrication have also been discussed.This article is categorized under:Nanotechnology Approaches to Biology > Nanoscale Systems in BiologyImplantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement}, number={2}, journal={WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY}, publisher={Wiley}, author={Chansoria, Parth and Schuchard, Karl and Shirwaiker, Rohan A.}, year={2021}, month={Mar} }