Abstract |
A packed Cytodex 3 microbead array was fabricated as a simple three-dimensional (3-D) cell-based biosensing format. Resting membrane potentials and voltage-gated calcium channel (VGCC) function of SH-SY5Y human neuroblastoma cells cultured on the microbead array versus collagen-coated flat (2-D) substrates were evaluated by confocal microscopy with a potentiometric dye, tetramethylrhodamine methyl ester, and a calcium fluorescent indicator, Calcium Green-1. SH-SY5Y cells, differentiated with 1mM dibutyryl cAMP and 2.5 microM 5-bromodeoxyuridine, showed significant resting membrane potential establishment on the topographical scaffolds in a period of 13 days into differentiation, in contrast to the previously reported insignificant resting membrane potential establishment of the same cells within collagen hydrogels. On days 2, 8 and 13 into differentiation, cells on collagen-coated flat substrates developed resting membrane potentials of -6.0+/-19.5 mV (n=198), -30.5+/-19.9 mV (n=191) and -21.7+/-18.9 mV (n=308), in contrast to values for cells on 3-D scaffolds of -25.8+/-14.7 mV (n=112), -37.6+/-13.1 mV (n=120) and -28.7+/-12.2 mV (n=158), respectively. The development of VGCC function, as measured by percentage of cells responsive to 50 mM high K(+) depolarization, was significantly slower for cells on 3-D scaffolds (20.0% on day 13 into differentiation) than for cells on 2-D substrates (30.7% on day 8 into differentiation). The exaggerated 2-D cell calcium dynamics, in comparison with those of 3-D cells, is consistent with previous 2-D/3-D comparative studies. This study established the rationale and feasibility of the microbead array format for 3-D cell-based biosensing.
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Authors | Z-Z Wu, Y-P Zhao, W S Kisaalita |
Journal | Biosensors & bioelectronics
(Biosens Bioelectron)
Vol. 22
Issue 5
Pg. 685-93
(Dec 15 2006)
ISSN: 0956-5663 [Print] England |
PMID | 16540306
(Publication Type: Evaluation Study, Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)
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Chemical References |
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Topics |
- Biosensing Techniques
(instrumentation, methods)
- Calcium Channels
(metabolism)
- Cell Culture Techniques
(instrumentation, methods)
- Cell Line, Tumor
- Equipment Design
- Equipment Failure Analysis
- Humans
- Membrane Potentials
- Microspheres
- Neuroblastoma
(pathology, physiopathology)
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