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- Creators: Chemical Engineering Program
- Creators: Dean, W.P. Carey School of Business
Description
Current wound closure technology is limited, and lacks key elements \u2014 such as the formation of an immediate seal \u2014 that could otherwise resolve some of the common and life threatening complications associated with certain surgeries. Previous research has produced nanosealants capable of providing that immediate seal through the use of laser activation with a near infrared laser. Here, we have developed a biocompatible suture utilizes the same mechanics to provide the tensile strength needed to replace or supplement existing suture lines. Laser activated tissue integrating sutures (LATIS), are shown to have 75% of the tensile strength of commercially available PGA sutures, while still exhibiting the same laser mediated localized heating effect at power densities of as low as 1.6 W/cm2. LATIS has been shown to reach the temperature ranges needed for protein interdigitation, but suffers from low wet mechanical strength. Preparatory steps or solvents for chemical crosslinking generally dehydrate LATIS sutures, causing a shriveling effect that weakens the overall mechanical strength of the suture. To resolve this, a new method of drying, by which LATIS sutures are dried under tension on a suspended platform, has been shown to decrease control suture strength, but restore the strength of chemically treated LATIS sutures to the level of control sutures or above. These promising results suggest that follow-up work with chemical cross-linkers may produce the increases in LATIS wet strength that are needed for its implementation in deeper tissue surgeries.
ContributorsChang, Andy (Author) / Rege, Kaushal (Thesis director) / Goklany, Sheba (Committee member) / School of Molecular Sciences (Contributor) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Carbon allotropes are the basis for many exciting advancements in technology. While sp² and sp³ hybridizations are well understood, the sp¹ hybridized carbon has been elusive. However, with recent advances made using a pulsed laser ablation in liquid technique, sp¹ hybridized carbon allotropes have been created. The fabricated carbon chain is composed of sp¹ and sp³ hybridized bonds, but it also incorporates nanoparticles such as gold or possibly silver to stabilize the chain. The polyyne generated in this process is called pseudocarbyne due to its striking resemblance to the theoretical carbyne. The formation of these carbon chains is yet to be fully understood, but significant progress has been made in determining the temperature of the plasma in which the pseudocarbyne is formed. When a 532 nm pulsed laser with a pulsed energy of 250 mJ and pulse length of 10ns is used to ablate a gold target, a peak temperature of 13400 K is measured. When measured using Laser-Induced Breakdown spectroscopy (LIBS) the average temperature of the neutral carbon plasma over one second was 4590±172 K. This temperature strongly suggests that the current theoretical model used to describe the temperature at which pseudocarbyne generates is accurate.
ContributorsWala, Ryland Gerald (Co-author) / Wala, Ryland (Co-author) / Sayres, Scott (Thesis director) / Steimle, Timothy (Committee member) / Drucker, Jeffery (Committee member) / Historical, Philosophical & Religious Studies (Contributor) / Dean, W.P. Carey School of Business (Contributor) / Department of Physics (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05