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TRACK 6 TRACK 6 Technical Program

that a CS/PEO-FI nanofiber scaffold could be used as a tunable biphasic Chang Liu, Houston Methodist Research Institute, Houston, TX,
drug-delivery platform for wound dressing and other clinical applications. United States, Tony Y. Hu, Houston Methodist Research Insititute,
Houston, TX, United States

Cell-On-Chip Stretchable Platform For Mammalian Cells Studies Tuberculosis disease (TB) by Mycobacterium tuberculosis (Mtb) infection
poses a significant public health challenge to both the patients and the wid-
Poster Presentation. NEMB2016-5944 er international community. The current “gold standard” for TB diagnosis and
treatment monitoring in adults as well as pediatric patients relies heavily on
Xudong Zhang, City College of New York, New York, NY, United time-consuming bacterial culturing methods. For this reason, rapid screen-
ing and accurate diagnosis of active TB is still challenging and critically
States, Fang Li, New York Institute of Technology, New York, NY, needed for global TB control efforts. In this study, we present a rapid and
United States, Ioana Voiculescu, City College of New York, New streamlined technology, using nanoporous silica thin films, which are opti-
York, NY, United States mized for pore size, geometry, capillary force, and film thickness, to isolate
Mtb antigens in laboratory and clinical samples for rapid TB screening. This
CELL-ON-CHIP STRETCHABLE PLATFORM FOR MAMMALIAN CELLS STUDIES technology, referred to here as NanoTrap, is integrated with the detection
capability of the high-throughput matrix-assisted laser desorption/ionization
Research in stretchable electrodes has long history and broad range of time-of flight mass spectrometry (MALDI-TOF MS) to screen and identify frag-
materials and electrode designs were reported in literature. The stretchable ments of the Mtb antigen, CFP-10, from complex human bodily fluid samples,
electrodes could be fabricated from gold, platinum or single walls carbon without use of immunoaffinity agents. With the use of this comprehensive
nanotubes. The electrodes fabricated on stretchable substrate reported approach, we clearly distinguished a clinical isolate of active TB patients
in the literature are passive electrodes used to in vivo record the electric from nonTB species infection patients, latent TB infection patients, as well as
field of the heart. The ECIS electrodes fabricated in this research are active healthy controls by detecting CFP-10 from the blood circulation. This assay
electrodes that are exposed to ac voltage and are part of an electrochem- can reach a detection limit of 1nM with a 90% sensitivity and a 99% speci-
ical sensor. Endothelial function involved in endothelial damage, arterial ficity for the antigen CFP-10. Our strategy has significant potential to fill the
degeneration, plaque formation. Mechanical stress caused by blood flow conceptual and technical gaps in rapid diagnosis of active TB disease.
and pressure can influence the function of endothelia cells. Therefore, study
the endothelial response to mechanical stimuli in vitro assists understanding
the endothelial function and mechanisms. ECIS sensor has been shown to Minimally Invasive Curved Microneedle for Innocuous Treatment
be able to evaluate cell function, morphology and behavior. This paper pres- of Retinal Detachment
ents the fabrication and testing of electric cell-substrate impedance spec-
troscopy (ECIS) electrodes on a stretchable membrane, which can evaluate
the influence of mechanical stimuli on endothelial functions underwent cyclic Poster Presentation. NEMB2016-6165
stretch. It’s the first time the ECIS sensors were fabricated on a stretchable
substrate and ECIS measurements on mammalian cells under 15% cyclic Yonghao Ma, Yonsei University, Seoul, Korea (Republic)
strain were successfully demonstrated. A chemical was used to form strong
chemical bond between gold electrodes of ECIS sensor and polymer mem- Retinal detachment has been a serious vision threatening disease. Consen-
brane, which enable the electrodes keep good conductive ability during sus treatment of retinal detachment is the re-attachment of retina onto cho-
cyclic stretch. The stretchable membrane integrated with the ECIS sensor roid. Although there are various surgical methods for treatment of retinal de-
can simulate and replicate the dynamic environment of organism and enable tachment, no satisfactory visual outcome has been obtained without side ef-
the analysis of the cells activity involved in cells attachment and proliferation fects such as unintended retinal tear, surrounding tissue damage and severe
in vitro. Bovine aortic endothelial cells (BAEC) were used to evaluate the en- hemorrhage. In order to minimize surgical side effects, we developed novel
dothelial function influenced by mechanical stimuli in this research because curved microneedle, which has specific features such as 30° curved hollow
they undergo in vivo cyclic physiologic elongation produced by the blood metallic microneedle with 15° beveled tip, 80 µm inner diameter and 100 µm
circulation in the arteries. The ECIS sensor fabrication has two main steps. outer diameter for suction of high viscous sub-retinal fluid with minimally in-
Firstly, a gold film was deposited on a glass slide using a shadow mask and vasive and safe application. Stable drainage of sub-retinal fluid by UDM was
gold sputtering technique. Secondly, a thin PDMS membrane that was pre- demonstrated with in vitro and ex vivo experiments. Invisible retinal hole
stretch 20%. Finally, the gold electrodes on glass slide were stamped onto on the re-attached retina was made by UDM whereas 200 µm diameter of
stretched PDMS membrane. A probe station was used to evaluate the Au retinal large hole and incurring choroidal damage was induced by traditional
electrodes conductive ability, since the wrinkles and cracks will be gener- hypodermic needle. In conclusion, UDM is a potential alternative to tradition-
ated on the Au electrodes during stretch. The inherent resistance values al surgical needle for innocuous treatment of retinal detachment.
fluctuated between 120 Ω and 200 Ω during stretch, which was acceptable
since the impedance of cell monolayer is more than thousands ohms. The
BAEC were cultured on the stretchable ECIS sensors mounted on a linear
motor. The impedance data was acquired at the end of each stretch/release
cycle. Firstly, the BAECs were passively cultured for 50 hours. Then the cy-
clic stretch of 15% was applied for 35 hours. When the cyclic stretch was ap-
plied the impedance values of cell monolayer were 660 Ω. The impedance
decreased during the initial 5 hours of cyclic strain due to the degradation
of intercellular junction. In time, the cell attachment and proliferation was im-
proved by the cyclic and the corresponding final impedance was 862.16 Ω.
As reported in the literature endothelial cells exhibited an increase in prolif-
eration in response to stretch. This study is the first time ECIS measurements
were performed on a stretchable substrate, which enables the BAEC subject
to cyclic strains for long period of time.

Improved Clinical Diagnosis of Tuberculosis by Antibody-Free
Detection of Circulating Mycobacterium tuberculosis Antigen 93

Poster Presentation. NEMB2016-6085