Publications by authors named "Michael A Daniele"

32 Publications

Synthesis of sonicated fibrin nanoparticles that modulate fibrin clot polymerization and enhance angiogenic responses.

Colloids Surf B Biointerfaces 2021 Apr 29;204:111805. Epub 2021 Apr 29.

Joint Department of Biomedical Engineering, NC State University and UNC Chapel-Hill, Raleigh, NC, United States; Comparative Medicine Institute, NC State University, Raleigh, NC, United States. Electronic address:

Chronic wounds can occur when the healing process is disrupted and the wound remains in a prolonged inflammatory stage that leads to severe tissue damage and poor healing outcomes. Clinically used treatments, such as high density, FDA-approved fibrin sealants, do not provide an optimal environment for native cell proliferation and subsequent tissue regeneration. Therefore, new treatments outside the confines of these conventional fibrin bulk gel therapies are required. We have previously developed flowable, low-density fibrin nanoparticles that, when coupled to keratinocyte growth factor, promote cell migration and epithelial wound closure in vivo. Here, we report a new high throughput method for generating the fibrin nanoparticles using probe sonication, which is less time intensive than the previously reported microfluidic method, and investigate the ability of the sonicated fibrin nanoparticles (SFBN) to promote clot formation and cell migration in vitro. The SFBNs can form a fibrin gel when combined with fibrinogen in the absence of exogenous thrombin, and the polymerization rate and fiber density in these fibrin clots is tunable based on SFBN concentration. Furthermore, fibrin gels made with SFBNs support cell migration in an in vitro angiogenic sprouting assay, which is relevant for wound healing. In this report, we show that SFBNs may be a promising wound healing therapy that can be easily produced and delivered in a flowable formulation.
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http://dx.doi.org/10.1016/j.colsurfb.2021.111805DOI Listing
April 2021

Integrated non-invasive biochemical and biophysical sensing systems for health and performance monitoring: A systems perspective.

Biosens Bioelectron 2021 Jul 19;184:113249. Epub 2021 Apr 19.

Department of Electrical & Computer Engineering, North Carolina State University, 890 Oval Dr., Raleigh, NC, 27695, USA; Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, 911 Oval Dr., Raleigh, NC, 27695, USA. Electronic address:

Advances in materials, bio-recognition elements, transducers, and microfabrication techniques, as well as progress in electronics, signal processing, and wireless communication have generated a new class of skin-interfaced wearable health monitoring systems for applications in personalized medicine and digital health. In comparison to conventional medical devices, these wearable systems are at the cusp of initiating a new era of longitudinal and noninvasive sensing for the prevention, detection, diagnosis, and treatment of diseases at the molecular level. Herein, we provide a review of recent developments in wearable biochemical and biophysical systems. We survey the sweat sampling and collection methods for biochemical systems, followed by an assessment of biochemical and biophysical sensors deployed in current wearable systems with an emphasis on their hardware specifications. Specifically, we address how sweat collection and sample handling platforms may be a rate limiting technology to realizing the clinical translation of wearable health monitoring systems; moreover, we highlight the importance of achieving both longitudinal sensing and assessment of intrapersonal variation in sweat-blood correlations to have the greatest clinical impact. Lastly, we assess a snapshot of integrated wireless wearable systems with multimodal sensing capabilities, and we conclude with our perspective on the state-of-the-art and the required developments to achieve the next-generation of integrated wearable health and performance monitoring systems.
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http://dx.doi.org/10.1016/j.bios.2021.113249DOI Listing
July 2021

Microphysiological System for High-Throughput Computer Vision Measurement of Microtissue Contraction.

ACS Sens 2021 03 3;6(3):985-994. Epub 2021 Mar 3.

Joint Department of Biomedical Engineering, University of North Carolina-Chapel Hill/North Carolina State University, Raleigh 27695, North Carolina, United States.

The ability to measure microtissue contraction in vitro can provide important information when modeling cardiac, cardiovascular, respiratory, digestive, dermal, and skeletal tissues. However, measuring tissue contraction in vitro often requires the use of high number of cells per tissue construct along with time-consuming microscopy and image analysis. Here, we present an inexpensive, versatile, high-throughput platform to measure microtissue contraction in a 96-well plate configuration using one-step batch imaging. More specifically, optical fiber microprobes are embedded in microtissues, and contraction is measured as a function of the deflection of optical signals emitted from the end of the fibers. Signals can be measured from all the filled wells on the plate simultaneously using a digital camera. An algorithm uses pixel-based image analysis and computer vision techniques for the accurate multiwell quantification of positional changes in the optical microprobes caused by the contraction of the microtissues. Microtissue constructs containing 20,000-100,000 human ventricular cardiac fibroblasts (NHCF-V) in 6 mg/mL collagen type I showed contractile displacements ranging from 20-200 μm. This highly sensitive and versatile platform can be used for the high-throughput screening of microtissues in disease modeling, drug screening for therapeutics, physiology research, and safety pharmacology.
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http://dx.doi.org/10.1021/acssensors.0c02172DOI Listing
March 2021

Cardiac Stromal Cell Patch Integrated with Engineered Microvessels Improves Recovery from Myocardial Infarction in Rats and Pigs.

ACS Biomater Sci Eng 2020 11 5;6(11):6309-6320. Epub 2020 Oct 5.

Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, North Carolina 27695, United States.

The vascularized cardiac patch strategy is promising for ischemic heart repair after myocardial infarction (MI), but current fabrication processes are quite complicated. Vascularized cardiac patches that can promote concurrent restoration of both the myocardium and vasculature at the injured site in a large animal model remain elusive. The safety and therapeutic benefits of a cardiac stromal cell patch integrated with engineered biomimetic microvessels (BMVs) were determined for treating MI. By leveraging a microfluidic method employing hydrodynamic focusing, we constructed the endothelialized microvessels and then encapsulated them together with therapeutic cardiosphere-derived stromal cells (CSCs) in a fibrin gel to generate a prevascularized cardiac stromal cell patch (BMV-CSC patch). We showed that BMV-CSC patch transplantation significantly promoted cardiac function, reduced scar size, increased viable myocardial tissue, promoted neovascularization, and suppressed inflammation in rat and porcine MI models, demonstrating enhanced therapeutic efficacy compared to conventional cardiac stromal cell patches. BMV-CSC patches did not increase renal and hepatic toxicity or exhibit immunogenicity. We noted a significant increase in endogenous progenitor cell recruitment to the peri-infarct region of the porcine hearts treated with BMV-CSC patch as compared to those that received control treatments. These findings establish the BMV-CSC patch as a novel engineered-tissue therapeutic for ischemic tissue repair.
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http://dx.doi.org/10.1021/acsbiomaterials.0c00942DOI Listing
November 2020

Rational design of direct electron transfer type l-lactate dehydrogenase for the development of multiplexed biosensor.

Biosens Bioelectron 2021 Mar 25;176:112933. Epub 2020 Dec 25.

Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill, North Carolina State University, Chapel Hill, NC, 27599, USA. Electronic address:

The development of wearable multiplexed biosensors has been focused on systems to measure sweat l-lactate and other metabolites, where the employment of the direct electron transfer (DET) principle is expected. In this paper, a fusion enzyme between an engineered l-lactate oxidase derived from Aerococcus viridans, AvLOx A96L/N212K mutant, which is minimized its oxidase activity and b-type cytochrome protein was constructed to realize multiplexed DET-type lactate and glucose sensors. The sensor with a fusion enzyme showed DET to a gold electrode, with a limited operational range less than 0.5 mM. A mutation was introduced into the fusion enzyme to increase K value and eliminate its substrate inhibition to construct "b2LOxS". Together with the employment of an outer membrane, the detection range of the sensor with b2LOxS was expanded up to 10 mM. A simultaneous lactate and glucose monitoring system was constructed using a flexible thin-film multiplexed electrodes with b2LOxS and a DET-type glucose dehydrogenase, and evaluated their performance in the artificial sweat. The sensors achieved simultaneous detection of lactate and glucose without cross-talking error, with the detected linear ranges of 0.5-20 mM for lactate and 0.1-5 mM for glucose, sensitivities of 4.1 nA/mM∙mm for lactate and 56 nA/mM∙mm for glucose, and limit of detections of 0.41 mM for lactate and 0.057 mM for glucose. The impact of the presence of electrochemical interferants (ascorbic acid, acetaminophen and uric acid), was revealed to be negligible. This is the first report of the DET-type enzyme based lactate and glucose dual sensing systems.
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http://dx.doi.org/10.1016/j.bios.2020.112933DOI Listing
March 2021

Rheological Properties of Coordinated Physical Gelation and Chemical Crosslinking in Gelatin Methacryloyl (GelMA) Hydrogels.

Macromol Biosci 2020 12 28;20(12):e2000183. Epub 2020 Aug 28.

Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina, Chapel Hill, 911 Oval Dr., Raleigh, NC, 27695, USA.

Synthetically modified proteins, such as gelatin methacryloyl (GelMA), are growing in popularity for bioprinting and biofabrication. GelMA is a photocurable macromer that can rapidly form hydrogels, while also presenting bioactive peptide sequences for cellular adhesion and proliferation. The mechanical properties of GelMA are highly tunable by modifying the degree of substitution via synthesis conditions, though the effects of source material and thermal gelation have not been comprehensively characterized for lower concentration gels. Herein, the effects of animal source and processing sequence are investigated on scaffold mechanical properties. Hydrogels of 4-6 wt% are characterized. Depending on the temperature at crosslinking, the storage moduli for GelMA derived from pigs, cows, and cold-water fish range from 723 to 7340 Pa, 516 to 3484 Pa, and 294 to 464 Pa, respectively. The maximum storage moduli are achieved only by coordinated physical gelation and chemical crosslinking. In this method, the classic thermo-reversible gelation of gelatin occurs when GelMA is cooled below a thermal transition temperature, which is subsequently "locked in" by chemical crosslinking via photocuring. The effects of coordinated physical gelation and chemical crosslinking are demonstrated by precise photopatterning of cell-laden microstructures, inducing different cellular behavior depending on the selected mechanical properties of GelMA.
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http://dx.doi.org/10.1002/mabi.202000183DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7738368PMC
December 2020

Microphysiological systems for the modeling of wound healing and evaluation of pro-healing therapies.

J Mater Chem B 2020 08;8(32):7062-7075

Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina, Chapel Hill, 911 Oval Dr., Raleigh, NC 27695, USA. and Comparative Medicine Institute, North Carolina State University, 1060 William Moore Dr., Raleigh, NC 27606, USA and Department of Electrical & Computer Engineering, North Carolina State University, 890 Oval Dr., Raleigh, NC 27695, USA.

Wound healing is a multivariate process involving the coordinated response of numerous proteins and cell types. Accordingly, biomedical research has seen an increased adoption of the use of in vitro wound healing assays with complexity beyond that offered by traditional well-plate constructs. These microphysiological systems (MPS) seek to recapitulate one or more physiological features of the in vivo microenvironment, while retaining the analytical capacity of more reductionist assays. Design efforts to achieve relevant wound healing physiology include the use of dynamic perfusion over static culture, the incorporation of multiple cell types, the arrangement of cells in three dimensions, the addition of biomechanically and biochemically relevant hydrogels, and combinations thereof. This review provides a brief overview of the wound healing process and in vivo assays, and we critically review the current state of MPS and supporting technologies for modelling and studying wound healing. We distinguish between MPS that seek to inform a particular phase of wound healing, and constructs that have the potential to inform multiple phases of wound healing. This distinction is a product of whether analysis of a particular process is prioritized, or a particular physiology is prioritized, during design. Material selection is emphasized throughout, and relevant fabrication techniques discussed.
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http://dx.doi.org/10.1039/d0tb00544dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7460719PMC
August 2020

Wearable multiplexed biosensor system toward continuous monitoring of metabolites.

Biosens Bioelectron 2020 Apr 18;153:112038. Epub 2020 Jan 18.

Department of Electrical & Computer Engineering, North Carolina State University, 890 Oval Dr., Raleigh, NC, 27695, USA; Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, 911 Oval Dr., Raleigh, NC, 27695, USA. Electronic address:

Comprehensive metabolic panels are the most reliable and common methods for monitoring general physiology in clinical healthcare. Translation of this clinical practice to personal health and wellness tracking requires reliable, non-invasive, miniaturized, ambulatory, and inexpensive systems for continuous measurement of biochemical analytes. We report the design and characterization of a wearable system with a flexible sensor array for non-invasive and continuous monitoring of human biochemistry. The system includes signal conditioning, processing, and transmission parts for continuous measurement of glucose, lactate, pH, and temperature. The system can operate three discrete electrochemical cells. The system draws 15 mA under continuous operation when powered by a 3.7 V 150 mAh battery. The analog front-end of the electrochemical cells has four potentiostats and three multiplexers for multiplexed and parallel readout from twelve working electrodes. Utilization of redundant working electrodes improves the measurement accuracy of sensors by averaging chronoamperometric responses across the array. The operation of the system is demonstrated in vitro by simultaneous measurement of glucose and lactate, pH, and skin temperature. In benchtop measurements, the sensors are shown to have sensitivities of 26.31 μA mM·cm for glucose, 1.49 μA mM·cm for lactate, 54 mV·pH for pH, and 0.002 °C for temperature. With the custom wearable system, these values were 0.84 ± 0.03 mV μM·cm or glucose, 31.87 ± 9.03 mV mM·cm for lactate, 57.18 ± 1.43 mV·pH for pH, and 63.4 μV·°C for temperature. This miniaturized wearable system enables future evaluation of temporal changes of the sweat biomarkers.
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http://dx.doi.org/10.1016/j.bios.2020.112038DOI Listing
April 2020

Monitoring of Microphysiological Systems: Integrating Sensors and Real-Time Data Analysis toward Autonomous Decision-Making.

ACS Sens 2019 06 19;4(6):1454-1464. Epub 2019 Apr 19.

Joint Department of Biomedical Engineering , North Carolina State University and University of North Carolina, Chapel Hill , 911 Oval Drive , Raleigh , North Carolina 27695 , United States.

Microphysiological systems replicate human organ function and are promising technologies for discovery of translatable biomarkers, pharmaceuticals, and regenerative therapies. Because microphysiological systems require complex microscale anatomical structures and heterogeneous cell populations, a major challenge remains to manufacture and operate these products with reproducible and standardized function. In this Perspective, three stages of microphysiological system monitoring, including process, development, and function, are assessed. The unique features and remaining technical challenges for the required sensors are discussed. Monitoring of microphysiological systems requires nondestructive, continuous biosensors and imaging techniques. With such tools, the extent of cellular and tissue development, as well as function, can be autonomously determined and optimized by correlating physical and chemical sensor outputs with markers of physiological performance. Ultimately, data fusion and analyses across process, development, and function monitors can be implemented to adopt microphysiological systems for broad research and commercial applications.
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http://dx.doi.org/10.1021/acssensors.8b01549DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6876853PMC
June 2019

IL22 Inhibits Epithelial Stem Cell Expansion in an Ileal Organoid Model.

Cell Mol Gastroenterol Hepatol 2019 4;7(1):1-17. Epub 2018 Jul 4.

Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill/North Carolina State University, Chapel Hill, North Carolina; Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Electronic address:

Background & Aims: Crohn's disease is an inflammatory bowel disease that affects the ileum and is associated with increased cytokines. Although interleukin (IL)6, IL17, IL21, and IL22 are increased in Crohn's disease and are associated with disrupted epithelial regeneration, little is known about their effects on the intestinal stem cells (ISCs) that mediate tissue repair. We hypothesized that ILs may target ISCs and reduce ISC-driven epithelial renewal.

Methods: A screen of IL6, IL17, IL21, or IL22 was performed on ileal mouse organoids. Computational modeling was used to predict microenvironment cytokine concentrations. Organoid size, survival, proliferation, and differentiation were characterized by morphometrics, quantitative reverse-transcription polymerase chain reaction, and immunostaining on whole organoids or isolated ISCs. ISC function was assayed using serial passaging to single cells followed by organoid quantification. Single-cell RNA sequencing was used to assess expression patterns in ISCs and transit-amplifying (TA) progenitors. An IL22-transgenic mouse was used to confirm the impact of increased IL22 on proliferative cells in vivo.

Results: High IL22 levels caused decreased ileal organoid survival, however, resistant organoids grew larger and showed increased proliferation over controls. was expressed on only a subset of ISCs and TA progenitors. IL22-treated ISCs did not show appreciable differentiation defects, but ISC biomarker expression and self-renewal-associated pathway activity was reduced and accompanied by an inhibition of ISC expansion. In vivo, chronically increased IL22 levels, similar to predicted microenvironment levels, showed increases in proliferative cells in the TA zone with no increase in ISCs.

Conclusions: Increased IL22 limits ISC expansion in favor of increased TA progenitor cell expansion.
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http://dx.doi.org/10.1016/j.jcmgh.2018.06.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6199238PMC
April 2019

Cardiac Stem Cell Patch Integrated with Microengineered Blood Vessels Promotes Cardiomyocyte Proliferation and Neovascularization after Acute Myocardial Infarction.

ACS Appl Mater Interfaces 2018 Oct 19;10(39):33088-33096. Epub 2018 Sep 19.

Joint Department of Biomedical Engineering , University of North Carolina at Chapel Hill and North Carolina State University , Raleigh , North Carolina 27695 , United States.

Cardiac stem cell (CSC) therapy has shown preclinical and clinical evidence for ischemic heart repair but is limited by low cellular engraftment and survival after transplantation. Previous versions of the cardiac patch strategy improve stem cell engraftment and encourage repair of cardiac tissue. However, cardiac patches that can enhance cardiomyogenesis and angiogenesis at the injured site remain elusive. Therapies that target cardiomyocyte proliferation and new blood vessel formation hold great potential for the protection against acute myocardial infarction (MI). Here, we report a new strategy for creating a vascularized cardiac patch in a facile and modular fashion by leveraging microfluidic hydrodynamic focusing to construct the biomimetic microvessels (BMVs) that include human umbilical vein endothelial cells (HUVECs) lining the luminal surface and then encapsulating the BMVs in a fibrin gel spiked with human CSCs. We show that the endothelialized BMVs mimicked the natural architecture and function of capillaries and that the resultant vascularized cardiac patch (BMV-CSC patch) exhibited equivalent release of paracrine factors compared to those of coculture of genuine human CSCs and HUVECs after 7 days of in vitro culture. In a rat model of acute MI, the BMV-CSC patch therapy induced profound mitotic activities of cardiomyocytes in the peri-infarct region 4 weeks post-treatment. A significant increase in myocardial capillary density was noted in the infarcted hearts that received BMV-CSC patch treatment compared to the infarcted hearts treated with conventional CSC patches. The striking therapeutic benefits and the fast and facile fabrication of the BMV-CSC patch make it promising for practical applications. Our findings suggest that the BMV-CSC patch strategy may open up new possibilities for the treatment of ischemic heart injury.
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http://dx.doi.org/10.1021/acsami.8b13571DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6376980PMC
October 2018

Neuro-Nano Interfaces: Utilizing Nano-Coatings and Nanoparticles to Enable Next-Generation Electrophysiological Recording, Neural Stimulation, and Biochemical Modulation.

Adv Funct Mater 2018 Mar 7;28(12). Epub 2017 Jun 7.

Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, and North Carolina State University, 911 Oval Dr., Raleigh, NC 27695, USA.

Neural interfaces provide a window into the workings of the nervous system-enabling both biosignal recording and modulation. Traditionally, neural interfaces have been restricted to implanted electrodes to record or modulate electrical activity of the nervous system. Although these electrode systems are both mechanically and operationally robust, they have limited utility due to the resultant macroscale damage from invasive implantation. For this reason, novel nanomaterials are being investigated to enable new strategies to chronically interact with the nervous system at both the cellular and network level. In this feature article, the use of nanomaterials to improve current electrophysiological interfaces, as well as enable new nano-interfaces to modulate neural activity via alternative mechanisms, such as remote transduction of electromagnetic fields are explored. Specifically, this article will review the current use of nanoparticle coatings to enhance electrode function, then an analysis of the cutting-edge, targeted nanoparticle technologies being utilized to interface with both the electrophysiological and biochemical behavior of the nervous system will be provided. Furthermore, an emerging, specialized-use case for neural interfaces will be presented: the modulation of the blood-brain barrier.
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http://dx.doi.org/10.1002/adfm.201700239DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8049593PMC
March 2018

"Data characterizing microfabricated human blood vessels created via hydrodynamic focusing".

Data Brief 2017 Oct 15;14:156-162. Epub 2017 Jul 15.

Center for Bio/Molecular Science & Engineering US Naval Research Laboratory, 4555 Overlook Ave. SW, Washington D.C. 20375, United States.

This data article provides further detailed information related to our research article titled "Microfabricated Blood Vessels Undergo Neovascularization" (DiVito et al., 2017) [1], in which we report fabrication of human blood vessels using hydrodynamic focusing (HDF). Hydrodynamic focusing with advection inducing chevrons were used in concert to encase one fluid stream within another, shaping the inner core fluid into 'bullseye-like" cross-sections that were preserved through click photochemistry producing streams of cellularized hollow 3-dimensional assemblies, such as human blood vessels (Daniele et al., 2015a, 2015b, 2014, 2016; Roberts et al., 2016) [2], [3], [4], [5], [6]. Applications for fabricated blood vessels span general tissue engineering to organ-on-chip technologies, with specific utility in drug delivery and pharmacodynamics studies. Here, we report data regarding the construction of blood vessels including cellular composition and cell positioning within the engineered vascular construct as well as functional aspects of the tissues.
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http://dx.doi.org/10.1016/j.dib.2017.07.011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5545875PMC
October 2017

Microfabricated blood vessels undergo neoangiogenesis.

Biomaterials 2017 Sep 19;138:142-152. Epub 2017 May 19.

Center for Bio/Molecular Science & Engineering, U.S. Naval Research Laboratory, 4555 Overlook Ave. SW, Washington D.C., 20375, United States. Electronic address:

The greatest ambition and promise of tissue engineering is to manufacture human organs. Before "made-to-measure" tissues can become a reality [1-3], however, three-dimensional tissues must be reconstructed and characterized. The current inability to manufacture operational vasculature has limited the growth of engineered tissues. Here, free-standing, small diameter blood vessels with organized cell layers that recapitulate normal biological functionality are fabricated using microfluidic technology. Over time in culture, the endothelial cells form a monolayer on the luminal wall and remodel the scaffold with human extracellular matrix proteins. After integration into three-dimensional gels containing fibroblasts, the microvessels sprout and generate extended hollow branches that anastomose with neighboring capillaries to form a network. Both the microfabricated vessels and the extended sprouts support perfusion of fluids and particles. The ability to create cellularized microvessels that can be designed with a diameter of choice, produced by the meter, and undergo angiogenesis and anastomoses will be an extremely valuable tool for vascularization of engineered tissues. To summarize, ultraviolet (UV) photo-crosslinkable poly(ethylene glycol) and gelatin methacrylate polymers used in combination with sheath-flow microfluidics allow for the fabrication of small diameter blood vessels which undergo neoangiogenesis as well as other developmental processes associated with normal human blood vessel maturation. Once mature, these vessels can be embedded; perfused; cryogenically stored and respond to stimuli such as chemokines and shear stresses to mimic native human blood vessels. The applications range from tissue-on-chip systems for drug screening, characterization of normal and pathologic processes, and creation and characterization of engineered tissues for organ repair.
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http://dx.doi.org/10.1016/j.biomaterials.2017.05.012DOI Listing
September 2017

Electrolyte-Sensing Transistor Decals Enabled by Ultrathin Microbial Nanocellulose.

Sci Rep 2017 01 19;7:40867. Epub 2017 Jan 19.

Center for Bio/Molecular Science and Engineering, U.S. Naval Research Laboratory, 4555 Overlook Ave. SW, Washington D.C. 20375, USA.

We report an ultra-thin electronic decal that can simultaneously collect, transmit and interrogate a bio-fluid. The described technology effectively integrates a thin-film organic electrochemical transistor (sensing component) with an ultrathin microbial nanocellulose wicking membrane (sample handling component). As far as we are aware, OECTs have not been integrated in thin, permeable membrane substrates for epidermal electronics. The design of the biocompatible decal allows for the physical isolation of the electronics from the human body while enabling efficient bio-fluid delivery to the transistor via vertical wicking. High currents and ON-OFF ratios were achieved, with sensitivity as low as 1 mg·L.
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http://dx.doi.org/10.1038/srep40867DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5244378PMC
January 2017

Affinity purification of bacterial outer membrane vesicles (OMVs) utilizing a His-tag mutant.

Res Microbiol 2017 Feb - Mar;168(2):139-146. Epub 2016 Oct 20.

Center for Bio/Molecular Science & Engineering, Naval Research Laboratory, Washington, DC 20375, USA. Electronic address:

To facilitate the rapid purification of bacterial outer membrane vesicles (OMVs), we developed two plasmid constructs that utilize a truncated, transmembrane protein to present an exterior histidine repeat sequence. We chose OmpA, a highly abundant porin protein, as the protein scaffold and utilized the lac promoter to allow for inducible control of the epitope-presenting construct. OMVs containing mutant OmpA-His6 were purified directly from Escherichia coli culture media on an immobilized metal affinity chromatography (IMAC) Ni-NTA resin. This enabling technology can be combined with other molecular tools directed at OMV packaging to facilitate the separation of modified/cargo-loaded OMV from their wt counterparts. In addition to numerous applications in the pharmaceutical and environmental remediation industries, this technology can be utilized to enhance basic research capabilities in the area of elucidating endogenous OMV function.
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http://dx.doi.org/10.1016/j.resmic.2016.10.001DOI Listing
March 2017

Platinum Nanoparticle Decorated SiO Microfibers as Catalysts for Micro Unmanned Underwater Vehicle Propulsion.

ACS Appl Mater Interfaces 2016 Nov 1;8(45):30941-30947. Epub 2016 Nov 1.

Department of Mechanical Engineering, Iowa State University , Ames, Iowa 50011, United States.

Micro unmanned underwater vehicles (UUVs) need to house propulsion mechanisms that are small in size but sufficiently powerful to deliver on-demand acceleration for tight radius turns, burst-driven docking maneuvers, and low-speed course corrections. Recently, small-scale hydrogen peroxide (HO) propulsion mechanisms have shown great promise in delivering pulsatile thrust for such acceleration needs. However, the need for robust, high surface area nanocatalysts that can be manufactured on a large scale for integration into micro UUV reaction chambers is still needed. In this report, a thermal/electrical insulator, silicon oxide (SiO) microfibers, is used as a support for platinum nanoparticle (PtNP) catalysts. The mercapto-silanization of the SiO microfibers enables strong covalent attachment with PtNPs, and the resultant PtNP-SiO fibers act as a robust, high surface area catalyst for HO decomposition. The PtNP-SiO catalysts are fitted inside a micro UUV reaction chamber for vehicular propulsion; the catalysts can propel a micro UUV for 5.9 m at a velocity of 1.18 m/s with 50 mL of 50% (w/w) HO. The concomitance of facile fabrication, economic and scalable processing, and high performance-including a reduction in HO decomposition activation energy of 40-50% over conventional material catalysts-paves the way for using these nanostructured microfibers in modern, small-scale underwater vehicle propulsion systems.
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http://dx.doi.org/10.1021/acsami.6b10047DOI Listing
November 2016

Topically applied manganese-porphyrins BMX-001 and BMX-010 display a significant anti-inflammatory response in a mouse model of allergic dermatitis.

Arch Dermatol Res 2016 Dec 5;308(10):711-721. Epub 2016 Oct 5.

Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, 1060 William Moore Drive, Raleigh, NC, 27607, USA.

In this study, we topically administered two antioxidant compounds, the manganese-porphyrin-derivatives BMX-001 and BMX-010, in a mouse model of allergic dermatitis and compared the efficacy for reduction of itch and inflammation. In vitro effects of BMX-001 and BMX-010 on keratinocytes, bone marrow derived dendritic cells (BMDCs) and T-cells were initially analysed. For assessment of scratching behaviour, BMX-001 and BMX-010 (0.01 and 0.1 %) were topically applied 16 h and/or 1 h before compound 48/80 or toluene-2,4,-diisocyanate (TDI) challenge in a TDI induced mouse dermatitis model. Additionally, assessment of allergic skin inflammation was performed in a similar manner in the TDI model. Post-treatment ear thickness was measured 24 h after TDI challenge and compared to basal values. The mice were sacrificed and the ear auricle was removed for further analysis. In vitro, both BMX substances significantly inhibited cytokine production of keratinocytes as well as of BMDC and T-cell proliferation. Topical treatment with BMX cream resulted in a significant decrease in scratching behaviour in the compound 48/80 model, but not in the TDI model. Mice treated with BMX-001 and BMX-010 showed a moderate dose dependent decrease in ear thickness, and interestingly, the concentration of the cytokines IL-1β and IL-4 in inflamed skin was reduced by 80-90 % by all treatment options. These first results suggest the potential benefit of a BMX-001 and BMX-010 cream for the treatment of allergic-inflammatory skin diseases.
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http://dx.doi.org/10.1007/s00403-016-1693-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7945677PMC
December 2016

Microvessel manifold for perfusion and media exchange in three-dimensional cell cultures.

Biomicrofluidics 2016 Sep 23;10(5):054109. Epub 2016 Sep 23.

Center for Bio/Molecular Science and Engineering , U.S. Naval Research Laboratory, 4555 Overlook Ave., Washington, DC 20375, USA.

Integrating a perfusable microvasculature system is a substantial challenge for "on-chip" tissue models. We have developed an inclusive on-chip platform that is capable of maintaining laminar flow through porous biosynthetic microvessels. The biomimetic microfluidic device is able to deliver and generate a steady perfusion of media containing small-molecule nutrients, drugs, and gases in three-dimensional cell cultures, while replicating flow-induced mechanical stimuli. Here, we characterize the diffusion of small molecules from the perfusate, across the microvessel wall, and into the matrix of a 3D cell culture.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5035297PMC
http://dx.doi.org/10.1063/1.4963145DOI Listing
September 2016

Nanoparticles and direct immunosuppression.

Exp Biol Med (Maywood) 2016 05;241(10):1064-73

Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina, Chapel Hill, Raleigh, NC 27695, USA Department of Electrical & Computer Engineering, North Carolina State University, Raleigh, NC 27695, USA

Targeting the immune system with nanomaterials is an intensely active area of research. Specifically, the capability to induce immunosuppression is a promising complement for drug delivery and regenerative medicine therapies. Many novel strategies for immunosuppression rely on nanoparticles as delivery vehicles for small-molecule immunosuppressive compounds. As a consequence, efforts in understanding the mechanisms in which nanoparticles directly interact with the immune system have been overshadowed. The immunological activity of nanoparticles is dependent on the physiochemical properties of the nanoparticles and its subsequent cellular internalization. As the underlying factors for these reactions are elucidated, more nanoparticles may be engineered and evaluated for inducing immunosuppression and complementing immunosuppressive drugs. This review will briefly summarize the state-of-the-art and developments in understanding how nanoparticles induce immunosuppressive responses, compare the inherent properties of nanomaterials which induce these immunological reactions, and comment on the potential for using nanomaterials to modulate and control the immune system.
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http://dx.doi.org/10.1177/1535370216650053DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4950368PMC
May 2016

Sequestering survivin to functionalized nanoparticles: a strategy to enhance apoptosis in cancer cells.

Biomater Sci 2016 Apr 4;4(4):614-26. Epub 2016 Feb 4.

Center for Optical Materials Science and Engineering Technologies, Department of Materials Science & Engineering, Clemson University, Clemson, SC 29634, USA.

Survivin belongs to the family of inhibitor of apoptosis proteins (IAP) and is present in most cancers while being below detection limits in most terminally differentiated adult tissues, making it an attractive protein to target for diagnostic and, potentially, therapeutic roles. Sub-100 nm poly(propargyl acrylate) (PA) particles were surface modified through the copper-catalyzed azide/alkyne cycloaddition of an azide-terminated survivin ligand derivative (azTM) originally proposed by Abbott Laboratories and speculated to bind directly to survivin (protein) at its dimer interface. Using affinity pull-down studies, it was determined that the PA/azTM nanoparticles selectively bind survivin and the particles can enhance apoptotic cell death in glioblastoma cell lines and other survivin over-expressing cell lines such as A549 and MCF7 relative to cells incubated with the original Abbott-derived small molecule inhibitor.
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http://dx.doi.org/10.1039/c5bm00580aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4803599PMC
April 2016

Bacterial Nanobioreactors--Directing Enzyme Packaging into Bacterial Outer Membrane Vesicles.

ACS Appl Mater Interfaces 2015 Nov 29;7(44):24963-72. Epub 2015 Oct 29.

Sotera Defense Solution, Inc. 7230 Lee DeForest Drive, Columbia, Maryland 21046, United States.

All bacteria shed outer membrane vesicles (OMVs) loaded with a diverse array of small molecules, proteins, and genetic cargo. In this study we sought to hijack the bacterial cell export pathway to simultaneously produce, package, and release an active enzyme, phosphotriesterase (PTE). To accomplish this goal the SpyCatcher/SpyTag (SC/ST) bioconjugation system was utilized to produce a PTE-SpyCatcher (PTE-SC) fusion protein and a SpyTagged transmembrane porin protein (OmpA-ST), known to be abundant in OMVs. Under a range of physiological conditions the SpyTag and SpyCatcher domains interact with one another and form a covalent isopeptide bond driving packaging of PTE into forming OMVs. The PTE-SC loaded OMVs are characterized for size distribution, number of vesicles produced, cell viability, packaged PTE enzyme kinetics, OMV loading efficiency, and enzyme stability following iterative cycles of freezing and thawing. The PTE-loaded OMVs exhibit native-like enzyme kinetics when assayed with paraoxon as a substrate. PTE is often toxic to expression cultures and has a tendency to lose activity with improper handling. The coexpression of OmpA-ST with PTE-SC, however, greatly improved the overall PTE production levels by mitigating toxicity through exporting of the PTE-SC and greatly enhanced packaged enzyme stability against iterative cycles of freezing and thawing.
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http://dx.doi.org/10.1021/acsami.5b08811DOI Listing
November 2015

Sweet substrate: a polysaccharide nanocomposite for conformal electronic decals.

Adv Mater 2015 Mar 3;27(9):1600-6. Epub 2014 Dec 3.

Center for Bio/Molecular Science and Engineering, U.S. Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, D.C. 20375, USA.

A conformal electronic decal based on a polysaccharide circuit board (PCB) is fabricated and characterized. The PCBs are laminates composed of bioderived sugars - nanocellulose and pullulan. The PCB and decal transfer are a bioactive material system for supporting electronic devices capable of conforming to bio-logical surfaces.
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http://dx.doi.org/10.1002/adma.201404445DOI Listing
March 2015

Platinum-paper micromotors: an urchin-like nanohybrid catalyst for green monopropellant bubble-thrusters.

ACS Appl Mater Interfaces 2014 Oct 30;6(20):17837-47. Epub 2014 Sep 30.

Department of Mechanical Engineering, Iowa State University , 2104 Black Engineering, Ames, Iowa 50011, United States.

Platinum nanourchins supported on microfibrilated cellulose films (MFC) were fabricated and evaluated as hydrogen peroxide catalysts for small-scale, autonomous underwater vehicle (AUV) propulsion systems. The catalytic substrate was synthesized through the reduction of chloroplatinic acid to create a thick film of Pt coral-like microstructures coated with Pt urchin-like nanowires that are arrayed in three dimensions on a two-dimensional MFC film. This organic/inorganic nanohybrid displays high catalytic ability (reduced activation energy of 50-63% over conventional materials and 13-19% for similar Pt nanoparticle-based structures) during hydrogen peroxide (H2O2) decomposition as well as sufficient propulsive thrust (>0.5 N) from reagent grade H2O2 (30% w/w) fuel within a small underwater reaction vessel. The results demonstrate that these layered nanohybrid sheets are robust and catalytically effective for green, H2O2-based micro-AUV propulsion where the storage and handling of highly explosive, toxic fuels are prohibitive due to size-requirements, cost limitations, and close person-to-machine contact.
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http://dx.doi.org/10.1021/am504525eDOI Listing
October 2014

3D hydrodynamic focusing microfluidics for emerging sensing technologies.

Biosens Bioelectron 2015 May 7;67:25-34. Epub 2014 Jul 7.

Department of Biomedical Engineering, University of North Carolina-Chapel Hill and North Carolina State University, EB3 Mail Stop 7115, Raleigh, NC 27695-7115, USA. Electronic address:

While the physics behind laminar flows has been studied for 200 years, understanding of how to use parallel flows to augment the capabilities of microfluidic systems has been a subject of study primarily over the last decade. The use of one flow to focus another within a microfluidic channel has graduated from a two-dimensional to a three-dimensional process and the design principles are only now becoming established. This review explores the underlying principles for hydrodynamic focusing in three dimensions (3D) using miscible fluids and the application of these principles for creation of biosensors, separation of cells and particles for sample manipulation, and fabrication of materials that could be used for biosensors. Where sufficient information is available, the practicality of devices implementing fluid flows directed in 3D is evaluated and the advantages and limitations of 3D hydrodynamic focusing for the particular application are highlighted.
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http://dx.doi.org/10.1016/j.bios.2014.07.002DOI Listing
May 2015

Microfluidic strategies for design and assembly of microfibers and nanofibers with tissue engineering and regenerative medicine applications.

Adv Healthc Mater 2015 Jan 23;4(1):11-28. Epub 2014 May 23.

Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, D.C., 20375, USA.

Fiber-based materials provide critical capabilities for biomedical applications. Microfluidic fiber fabrication has recently emerged as a very promising route to the synthesis of polymeric fibers at the micro and nanoscale, providing fine control over fiber shape, size, chemical anisotropy, and biological activity. This Progress Report summarizes advanced microfluidic methods for the fabrication of both microscale and nanoscale fibers and illustrates how different methods are enabling new biomedical applications. Microfluidic fabrication methods and resultant materials are explained from the perspective of their microfluidic device principles, including co-flow, cross-flow, and flow-shaping designs. It is then detailed how the microchannel design and flow parameters influence the variety of synthesis chemistries that can be utilized. Finally, the integration of biomaterials and microfluidic strategies is discussed to manufacture unique fiber-based systems, including cell scaffolds, cell encapsulation, and woven tissue matrices.
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http://dx.doi.org/10.1002/adhm.201400144DOI Listing
January 2015

Microfluidic fabrication of polymeric and biohybrid fibers with predesigned size and shape.

J Vis Exp 2014 Jan 8(83):e50958. Epub 2014 Jan 8.

Center for Bio/Molecular Science & Engineering, US Naval Research Laboratory.

A "sheath" fluid passing through a microfluidic channel at low Reynolds number can be directed around another "core" stream and used to dictate the shape as well as the diameter of a core stream. Grooves in the top and bottom of a microfluidic channel were designed to direct the sheath fluid and shape the core fluid. By matching the viscosity and hydrophilicity of the sheath and core fluids, the interfacial effects are minimized and complex fluid shapes can be formed. Controlling the relative flow rates of the sheath and core fluids determines the cross-sectional area of the core fluid. Fibers have been produced with sizes ranging from 300 nm to ~1 mm, and fiber cross-sections can be round, flat, square, or complex as in the case with double anchor fibers. Polymerization of the core fluid downstream from the shaping region solidifies the fibers. Photoinitiated click chemistries are well suited for rapid polymerization of the core fluid by irradiation with ultraviolet light. Fibers with a wide variety of shapes have been produced from a list of polymers including liquid crystals, poly(methylmethacrylate), thiol-ene and thiol-yne resins, polyethylene glycol, and hydrogel derivatives. Minimal shear during the shaping process and mild polymerization conditions also makes the fabrication process well suited for encapsulation of cells and other biological components.
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http://dx.doi.org/10.3791/50958DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4089404PMC
January 2014

Interpenetrating networks based on gelatin methacrylamide and PEG formed using concurrent thiol click chemistries for hydrogel tissue engineering scaffolds.

Biomaterials 2014 Feb 5;35(6):1845-56. Epub 2013 Dec 5.

Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, 4555 Overlook Ave, SW Washington, DC 20375, USA.

The integration of biological extracellular matrix (ECM) components and synthetic materials is a promising pathway to fabricate the next generation of hydrogel-based tissue scaffolds that more accurately emulate the microscale heterogeneity of natural ECM. We report the development of a bio/synthetic interpenetrating network (BioSINx), containing gelatin methacrylamide (GelMA) polymerized within a poly(ethylene glycol) (PEG) framework to form a mechanically robust network capable of supporting both internal cell encapsulation and surface cell adherence. The covalently crosslinked PEG network was formed by thiol-yne coupling, while the bioactive GelMA was integrated using a concurrent thiol-ene coupling reaction. The physical properties (i.e. swelling, modulus) of BioSINx were compared to both PEG networks with physically-incorporated gelatin (BioSINP) and homogenous hydrogels. BioSINx displayed superior physical properties and significantly lower gelatin dissolution. These benefits led to enhanced cytocompatibility for both cell adhesion and encapsulation; furthermore, the increased physical strength provided for the generation of a micro-engineered tissue scaffold. Endothelial cells showed extensive cytoplasmic spreading and the formation of cellular adhesion sites when cultured onto BioSINx; moreover, both encapsulated and adherent cells showed sustained viability and proliferation.
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http://dx.doi.org/10.1016/j.biomaterials.2013.11.009DOI Listing
February 2014

Protein triggered fluorescence switching of near-infrared emitting nanoparticles for contrast-enhanced imaging.

J Mater Chem B 2013 Sep 26;1(36):4542-4554. Epub 2013 Jul 26.

Center for Optical Materials Science and Engineering Technologies, Department of Materials Science & Engineering, Clemson University, Clemson, SC 29634-0971, USA.

Sub-100 nm colloidal particles which are surface-functionalized with multiple environmentally-sensitive moieties have the potential to combine imaging, early detection, and the treatment of cancer with a single type of long-circulating "nanodevice". Deep tissue imaging is achievable through the development of particles which are surface-modified with fluorophores that operate in the near-infrared (NIR) spectrum and where the fluorophore's signal can be maximized by "turning-on" the fluorescence only in the targeted tissue. We present a general approach for the synthesis of NIR emitting nanoparticles that exhibit a protein triggered activation/deactivation of the emission. Dispersing the particles into an aqueous solution, such as phosphate buffered saline (PBS), resulted in an aggregation of the hydrophobic fluorophores and a cessation of emission. The emission can be reinstated, or activated, by the conversion of the surface-attached fluorophores from an aggregate to a monomeric species with the addition of an albumin. This activated probe can be deactivated and returned to a quenched state by a simple tryptic digestion of the albumin. The methodology for emission switching offers a path to maximize the signal from the typically weak quantum yield inherent in NIR fluorophores.
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http://dx.doi.org/10.1039/c3tb20681eDOI Listing
September 2013

Magnetic nanoclusters exhibiting protein-activated near-infrared fluorescence.

ACS Nano 2013 Jan 12;7(1):203-13. Epub 2012 Dec 12.

Center for Optical Materials Science and Engineering Technologies, Department of Materials Science & Engineering, Clemson University, Clemson, South Carolina 29634-0971, USA.

Composite nanoclusters with chemical, magnetic, and biofunctionality offer broad opportunities for targeted cellular imaging. A key challenge is to load a high degree of targeting, imaging, and therapeutic functionality onto stable metal-oxide nanoparticles. Here we report a route for producing magnetic nanoclusters (MNCs) with alkyne surface functionality that can be utilized as multimodal imaging probes. We form MNCs composed of magnetic Fe(3)O(4) nanoparticles and poly(acrylic acid-co-propargyl acrylate) by the co-precipitation of iron salts in the presence of copolymer stabilizers. The MNCs were surface-modified with near-infrared (NIR) emitting fluorophore used in photodynamic therapy, an azide-modified indocyanine green. The fluorophores engaged and complexed with bovine serum albumin, forming an extended coverage of serum proteins on the MNCs. These proteins isolated indocyanine green fluorophores from the aqueous environment and induced an effective "turn-on" of NIR emission.
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http://dx.doi.org/10.1021/nn3037368DOI Listing
January 2013