Thomas A. Campbell

Additive manufacturing (AM) and nanotechnology: promises and challenges

Purpose – This paper aims to provide a review of available published literature in which nanostructures are incorporated into AM printing media as an attempt to improve the properties of the final printed part. The purpose of this article is to summarize the research done to date, to highlight successes in the field, and to identify opportunities that the union of AM and nanotechnology could bring to science and technology.Design/methodology/approach – Research in which metal, ceramic, and carbon nanomaterials have been incorporated into AM technologies such as stereolithography, laser sintering, fused filament fabrication, and three‐dimensional printing is presented. The results of the addition of nanomaterials into these AM processes are reviewed.Findings – The addition of nanostructured materials into the printing media for additive manufacturing affects significantly the properties of the final parts. Challenges in the application of nanomaterials to additive manufacturing are nevertheless numerous.Re...

Single walled carbon nanohorns as photothermal cancer agents.

Nanoparticles have significant potential as selective photo‐absorbing agents for laser based cancer treatment. This study investigates the use of single walled carbon nanohorns (SWNHs) as thermal enhancers when excited by near infrared (NIR) light for tumor cell destruction.

ADDITIVE MANUFACTURING AS A DISRUPTIVE TECHNOLOGY: IMPLICATIONS OF THREE-DIMENSIONAL PRINTING

67 Accepted November 20, 2012. Address correspondence to Thomas A. Campbell, Research Associate Professor, Associate Director for Outreach, Institute for Critical Technology and Applied Science (ICTAS), Virginia Tech, 325 Stanger Street, MC 0193, Blacksburg, VA 24061, USA. Tel: (540) 231-8359; Fax: (540) 231-0970; E-mail: tomca@vt.edu Additive MAnufActuring As A disruptive technology: iMplicAtions of three-diMensionAl printing

Cultivating Emerging and Black Swan Technologies

Emerging technologies, defined as contemporary cutting-edge developments in various fields of technology, are generally associated with the potential for large impact on society. In a recent op-ed, “The coming Tech-led Boom” (Wall Street Journal, January 30, 2012), Mills and Ottino list three grand technological transformations — big data, smart manufacturing, and the wireless revolution — poised to transform this century as much as telephony and electricity did in the 20th century. This list is by no means comprehensive and most likely misses technologies that are not yet recognized, but may still carry an extreme impact — i.e., the so-called Black Swans, as defined by New York Times best-selling author, Nassim Nicholas Taleb, in his book, The Black Swan. Taleb cites the example of three recently implemented technologies that most impact our world today — the Internet, the computer, and the laser — and notes that all three were unplanned, unpredicted, and unappreciated upon their discovery, and remained unappreciated well after initial use.In this paper, we will examine several emerging technologies, present a methodology to create a breeding ground for potential Black Swans, and finally discuss the societal and ethical aspects of these technologies.Copyright

Spatiotemporal Temperature and Cell Viability Measurement Following Laser Therapy in Combination With Carbon Nanohorns

Cancer remains one of the most deadly diseases today. Laser-induced photothermal therapy can provide a minimally invasive treatment alternative to surgical resection. The selectivity and effectiveness of laser therapy can be greatly enhanced when photoabsorbing nanoparticles such as nanoshells, single walled carbon nanotubes, multi-walled carbon nanotubes, or single wall carbon nanohorns (SWNHs) are introduced into the tissue. Prior studies have effectively used SWNHs combined with near infrared (NIR) laser light to target and destroy microbes [1]. We have previously reported increased tumor cell destruction when SWNHs were used in combination with laser therapy. The present work provides more extensive characterization of cell viability in response to laser therapy alone or in combination with SWNHs. Furthermore, the spatiotemporal temperature and cell viability in vitro in response to combinatorial SWNH-mediated laser therapies is determined using infrared thermometry and a novel viability algorithm, respectively. These new measurements will be critical for planning SWNH-mediated laser treatments where knowledge of the geometric distribution of temperature and cell death are critical to achieving the goal of selectively eliminating a tumor with specific spatial margins with minimal damage to surrounding healthy tissue.© 2010 ASME

Carbon Nanohorns as Photochemical and Photothermal Agents

Laser therapies based on photochemical or photothermal mechanisms can provide a minimally invasive and potentially more effective treatment alternative to conventional surgical resection procedures by delivering prescribed optical/thermal doses to a targeted tissue volume with minimal damage to intervening and surrounding tissues. However laser therapy effectiveness is limited due to nonspecific excitation/heating of target tissue which often results in healthy tissue injury. Nanostructures targeted to tumor cells and utilized in combination with laser excitation can enhance treatment effectiveness by increasing thermal deposition and generating toxic photo-chemical mediators in the form of reactive oxygen species for targeted cell destruction.Copyright