| AVS 63rd International Symposium & Exhibition | |
| MEMS and NEMS | Thursday Sessions |
| Session MN+BI-ThM |
| Session: | ‘Fantastic Voyage’ – the New Micro/Nano/Bio Systems Frontiers |
| Presenter: | Ryan Huiszoon, University of Maryland, College Park |
| Authors: | R.C. Huiszoon, University of Maryland, College Park S. Subramanian, University of Maryland, College Park T.E. Winkler, University of Maryland, College Park H.O. Sintim, Purdue University W.E. Bentley, University of Maryland, College Park R. Ghodssi, University of Maryland, College Park |
| Correspondent: | Click to Email |
New technologies, like capsule microsystems (Fig.1), have the potential to revolutionize medical care by autonomously locating and treating in vivo infections. Such implantable systems require 3D structures that cannot be fabricated using traditional photolithography. Additive manufacturing is the ideal tool that allows for rapid and detailed fabrication of such complex structures. However, 3D-printed implants, like their metal and ceramic counterparts, are vulnerable to biofilm infections [1]. Thus, it is essential to characterize treatments for these films on emerging 3D printable materials. In this work, we evaluate bacterial biofilm treatment on 3D-printed implant materials such as MED610.
Bacterial biofilms are the leading cause of implant infections. They form when planktonic bacteria adhere on a surface, secrete protective extracellular matrix and grow. They are highly resistant to antibiotics, allowing the infection to persist [2,3]. Microfluidics is a common and effective tool to evaluate biofilms in a controlled environment as it offers more clinically relevant data about biofilm growth and treatment [4].
In this work, we 3D printed open microfluidic channels (750μm wide x 400μm deep) on a Stratsys Connex3 polyjet printer. The open channels were sealed using sealing wrap, PDMS and glass, and clamped together using binder clips (Fig.2). Escherichia coli W3110 biofilms were grown in the micro-channels under Lysogeny Broth (LB) media flow at 120µl/hr for 24 hours. Subsequently, treatment with LB media (control), 10μg/mL gentamicin, 100μM autoinducer-2 (AI-2) analog (quorum sensing disruptor), or a combination of the latter two treatments was introduced into the various channels at the same flow rate for an additional 24 hours. The biofilms were then imaged through the open channels using an Olympus BX60 microscope (Fig.3). Treatment efficacy was evaluated as a percent change in channel surface coverage quantified using ImageJ. Bacterial biofilm coverage was reduced by 21%, 31% and 50% for gentamicin, analog and combination treatments respectively as compared to the untreated control, consistent with previous results (Fig.4) [2]. The combination treatment proved most effective, reducing biofilm coverage by 37% compared to the standard antibiotic-only therapy [2].
3D printed microfluidic test platforms offer an affordable way to experiment on new materials and can hasten the development of novel treatments. Additionally, the characterization of these materials brings us a step closer to making this technology a viable option for fabricating complex structures for implantable multi-purpose microsystems.