Browsing by Subject "electrospinning"

Now showing 1 - 6 of 6
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    Curcumin—A Natural Medicament for Root Canal Disinfection: Effects of Irrigation, Drug Release, and Photoactivation
    (Elsevier, 2019-11) Sotomil, Julian M.; Münchow, Eliseu A.; Pankajakshan, Divya; Spolnik, Kenneth J.; Ferreira, Jessica A.; Gregory, Richard L.; Bottino, Marco C.; Prosthodontics, School of Dentistry
    Introduction Curcumin incorporation into polymeric fibers was tested for its antimicrobial properties and potential use in root canal disinfection. Methods Curcumin-modified fibers were processed via electrospinning and tested against a 7-day old established Actinomyces naeslundii (An) biofilm. The medicaments tested were as follows: curcumin-modified fibers at 2.5 and 5.0 mg/mL, curcumin-based irrigant at 2.5 and 5.0 mg/mL, saline solution (negative control), and the following positive controls: 2% chlorhexidine, 1% NaOCl, and triple antibiotic paste (TAP, 1 mg/mL). All medicaments, except for the positive controls, were allocated according to the light exposure protocol: photoactivation with an LED every 30 s for 4 min or without photoactivation. After treatment, the medicaments were removed and 1 mL of saline solution was added; the biofilm was scraped from the well and used to prepare a 1:2000 dilution. Spiral plating was done using anaerobic blood agar plates. After 24 h, colony-forming units (CFU/mL, n=11/group) were counted to determine the antimicrobial effects. Results Data exhibited significant antimicrobial effects on positive control groups, followed by the curcumin irrigants, and lastly, the photoactivated curcumin-modified fibers. There was a significant reduction of viable bacteria in curcumin-based irrigants, which was greater than the TAP-treated group. Curcumin-free fibers, saline, and the non-photoactivated curcumin-modified fibers did not display antimicrobial activity. Conclusions Curcumin seems to be a potential alternative to TAP when controlling infection, but it requires a minimal concentration (2.5 mg/mL) to be effective. Photoactivation of curcumin-based medicaments seems to be essential to obtain greater antibiofilm activity.
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    Higher strength carbon fiber lithium-ion polymer battery embedded multifunctional composites for structural applications
    (Wiley Online Library, 2022-03-17) Biswas, Pias Kumar; Liyanage, Asel Ananda Habarakada; Jadhav, Mayur; Agarwal, Mangilal; Dalir, Hamid
    This study proposes and evaluates the structural integrity of a carbon fiber reinforced polymer (CFRP) composite containing encapsulated lithium-ion polymer (Li-Po) batteries. A comparison of various composite structures made of CFRP having the core of lithium-ion batteries is conducted. Electrospinning is globally recognized as a flexible and cost-effective method for generating continuous nanofilaments. In this study, epoxy-multiwalled carbon nanotubes (CNT/epoxy) were electrospun onto CFRP layers, which improved interfacial bonding and strong adhesion between the layers which ultimately worked as an effective packaging for Li-ion batteries. This composite structure showed enhanced mechanical strength compared to the standard CFRP laminate structure due to incorporating electrospun CNT/epoxy nanofibers in between the layers. An alternate method was proposed for comparison where CNT/epoxy was air sprayed onto the CFRP layers. CFRP structure containing airsprayed CNT/epoxy was found to be stronger than standard CFRP laminate structure, although not as strong as electrospun CNT/epoxy enhanced CFRP laminates. Finally, the design validation, manufacturing method, and electromechanical characterization of multifunctional energy storage composites (MESCs) were examined and compared. Electrochemical characterization showed that MESCs with electrospun CNT/epoxy nanofibers enhanced CFRP laminate under loading conditions had similar performance to the standard lithium-ion pouch cells without any loading. The mechanical robustness of the proposed CFRP composite structures enables their manufacturing as multifunctional energy-storage devices for electric vehicles and other structural applications.
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    A novel patient-specific three-dimensional drug delivery construct for regenerative endodontics
    (Wiley, 2018-10-03) Bottino, Marco C.; Albuquerque, Maria T. P.; Azabi, Asma; Münchow, Eliseu A.; Spolnik, Kenneth J.; Nör, Jacques E.; Edwards, Paul C.; Oral Pathology, Medicine and Radiology, School of Dentistry
    Evoked bleeding (EB) clinical procedure, comprising a disinfection step followed by periapical tissue laceration to induce the ingrowth of undifferentiated stem cells from the periodontal ligament and alveolar bone, is currently the only regenerative-based therapeutic approach to treating pulp tissue necrosis in undeveloped (immature) permanent teeth approved in the United States. Yet, the disinfection step using antibiotic-based pastes leads to cytotoxic, warranting a biocompatible strategy to promote root canal disinfection with no or minimal side-effects to maximize the regenerative outcomes. The purpose of this investigation was to develop a tubular three-dimensional (3D) triple antibiotic-eluting construct for intracanal drug delivery. Morphological (scanning electron microscopy), chemical (Fourier transform infrared spectroscopy), and mechanical (tensile testing) characteristics of the polydioxanone-based triple antibiotic-eluting fibers were assessed. The antimicrobial properties of the tubular 3D constructs were determined in vitro and in vivo using an infected (Actinomyces naeslundii) dentin tooth slice model and a canine method of periapical disease, respectively. The in vitro data indicated significant antimicrobial activity and the ability to eliminate bacterial biofilm inside dentinal tubules. In vivo histological findings demonstrated that, using the EB procedure, the tubular 3D triple antibiotic-eluting construct allowed the formation of an appropriate environment that led to apex closure and the ingrowth of a thin layer of osteodentin-like tissue into the root canal. Taken together, these findings indicate that our novel drug delivery construct is a promising biocompatible disinfection strategy for immature permanent teeth with necrotic pulps.
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    Overview of Nano-Fiber Mats Fabrication via Electrospinning and Morphology Analysis
    (MDPI, 2021) Ahmadian, Amirhossein; Shafiee, Abbas; Aliahmad, Nojan; Agarwal, Mangilal; Mechanical and Energy Engineering, School of Engineering and Technology
    Electrospun nano-fibers exhibit two significant properties: a high surface-to-volume ratio and a relatively defect-free molecular structure. Due to the high surface-to-volume ratio, electro-spun materials are well suited for activities requiring increased physical contact, such as providing a site for a chemical reaction or filtration of small-sized physical materials. However, electrospinning has many shortcomings, including difficulties in producing inorganic nanofibers and a limited number or variety of polymers used in the process. The fabrication of nanofiber bundles via electrospinning is explored in this analytical study and the relationship between all effective electrospinning parameters and the relative abundance of various fiber morphologies. Numerous variables could impact the fabrication of nanofibers, resulting in a variety of morphologies such as uniform, entangled, individual beads, beads-on-string, etc. Therefore, adequate ambient conditions and selecting the appropriate polymer and solvent for achieving a homogenous polymer solution and uniform with desired nanofiber properties for different applications of electro-spun materials are examined. Finally, the promising applications of nano-fine fibers in various fields achieved via electrospinning are studied in this paper.
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    Triple Antibiotic Polymer Nanofibers for Intracanal Drug Delivery: Effects on Dual Species Biofilm and Cell Function
    (Elsevier, 2016-10) Pankajakshan, Divya; Albuquerque, Maria T.P.; Evans, Joshua D.; Kamocka, Malgorzata M.; Gregory, Richard L.; Bottino, Marco C.; Biomedical and Applied Sciences, School of Dentistry
    Introduction Root canal disinfection and the establishment of an intracanal microenvironment conducive to the proliferation/differentiation of stem cells play a significant role in regenerative endodontics. This study was designed to (1) investigate the antimicrobial efficacy of triple antibiotic–containing nanofibers against a dual-species biofilm and (2) evaluate the ability of dental pulp stem cells (DPSCs) to adhere to and proliferate on dentin upon nanofiber exposure. Methods Seven-day-old dual-species biofilm established on dentin specimens was exposed for 3 days to the following: saline (control), antibiotic-free nanofibers (control), and triple antibiotic–containing nanofibers or a saturated triple antibiotic paste (TAP) solution (50 mg/mL in phosphate buffer solution). Bacterial viability was assessed using the LIVE/DEAD assay (Molecular Probes, Inc, Eugene, OR) and confocal laser scanning microscopy. For cyto-compatibility studies, dentin specimens after nanofiber or TAP (1 g/mL in phosphate buffer solution) exposure were evaluated for cell adhesion and spreading by actin-phalloidin staining. DPSC proliferation was assessed on days 1, 3, and 7. Statistics were performed, and significance was set at the 5% level. Results Confocal laser scanning microscopy showed significant bacterial death upon antibiotic-containing nanofiber exposure, differing significantly (P < .05) from antibiotic-free fibers and the control (saline). DPSCs showed enhanced adhesion/spreading on dentin specimens treated with antibiotic-containing nanofibers when compared with its TAP counterparts. The DPSC proliferation rate was similar on days 1 and 3 in antibiotic-free nanofibers, triple antibiotic–containing nanofibers, and TAP-treated dentin. Proliferation was higher (9-fold) on dentin treated with antibiotic-containing nanofibers on day 7 compared with TAP. Conclusions Triple antibiotic–containing polymer nanofibers led to significant bacterial death, whereas they did not affect DPSC attachment and proliferation on dentin.
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    Tubular Electrospun Composite Scaffolds for Potential Bone Tissue Engineering
    (Office of the Vice Chancellor for Research, 2014-04-11) Arman, Huseyin E; Li, Jiliang
    Electrospinning is an adaptable method in which polymer solutions or melts converted into micro or nano scale fibers. In this procedure, polymer solutions are loaded into 10 mL syringes that contained millimeter scale nozzles. High voltage (20-30 kV) was applied to polymer solutions at the tip of the nozzle to stabilize the surface tension by electrostatic force. The critical point where this stabilization occurred is called Taylor cone and it lets the droplets to turn into polymer sprays. The fibers were collected onto a tubular rotational collector, which was grounded. Different tubular scaffolds composed of pure polycaprolactone (PCL), small intestinal submucosa (SIS), hydroxyapatite (HA) and tricalciumphosphate (TCP) were prepared by using the electrospinning technique. 13 and 15 wt% pure PCL stock solutions were prepared by dissolution in 1,1,1,3,3,3-hexafluoro-2-propanol (HPF) and stirring at the room temperature until a viscous translucent liquid was acquired. Composite PCL/SIS and PCL/HA dopes were prepared from 10 wt% PCL stock by adding SIS or HA in an 8:1 (PCL:SIS, PCL:HA) dry weight ratio. Similarly, PCL/HA/TCP solutions were made from 13 wt% PCL stock by adding HA and TCP in a 8:1:1 dry weight ratio. Each individual scaffold will be scanned through electron microscope (ECM) to gather information about the % porosity and the diameter of the electrospun fibers. Mechanical testing will be conducted to measure the tensile strength of the fibers. Finally, implanting the tubular scaffolds into axolotls will test cell biocompatibility of the scaffolds.