TY - JOUR
T1 - Enzyme-containing hydrogel micropatterns serving a dual purpose of cell sequestration and metabolite detection
AU - Yan, Jun
AU - Sun, Yinghua
AU - Zhu, He
AU - Marcu, Laura
AU - Revzin, Alexander
N1 - Funding Information:
The authors thank Dr. Louie's lab from the Department of Biomedical Engineering of University of California, Davis for providing assistance with confocal microscope and spectrophotometer. We also thank Dr. Henrich's laboratory for help in cultivating macrophages. The work was supported by an NIH grant (R21CA126716) awarded to AR.
PY - 2009/4/15
Y1 - 2009/4/15
N2 - The integration of sensing elements with small groups of cells is a critical step towards miniaturization of cell cultivation and analysis. This paper describes the development of an optical, enzyme-based biosensor for local detection of hydrogen peroxide (H2O2) secreted by stimulated macrophages. Photolithographic patterning of horseradish peroxidase (HRP)-containing poly (ethylene glycol) (PEG) hydrogel microstructures was used to create sensing structures on the glass surface. Importantly, enzyme-entrapping hydrogel micropatterns did not support protein or cell deposition and allowed to guide attachment of macrophages next to the sensing elements. Amplex Red, an organic molecule that becomes fluorescent in the presence of H2O2 and HRP, was either immobilized inside hydrogel elements alongside enzyme molecules or added into the cell culture media during cell activation. The production of H2O2 after mitogenic stimulation of macrophages resulted in appearance of fluorescence in the HRP-containing hydrogel microstructures, with fluorescence intensity being a strong function of analyte concentration. The novel cell culture system with integrated sensing elements described here may be enhanced in the future by incorporating additional biorecognition elements to enable multi-metabolite detection at the site of a cell.
AB - The integration of sensing elements with small groups of cells is a critical step towards miniaturization of cell cultivation and analysis. This paper describes the development of an optical, enzyme-based biosensor for local detection of hydrogen peroxide (H2O2) secreted by stimulated macrophages. Photolithographic patterning of horseradish peroxidase (HRP)-containing poly (ethylene glycol) (PEG) hydrogel microstructures was used to create sensing structures on the glass surface. Importantly, enzyme-entrapping hydrogel micropatterns did not support protein or cell deposition and allowed to guide attachment of macrophages next to the sensing elements. Amplex Red, an organic molecule that becomes fluorescent in the presence of H2O2 and HRP, was either immobilized inside hydrogel elements alongside enzyme molecules or added into the cell culture media during cell activation. The production of H2O2 after mitogenic stimulation of macrophages resulted in appearance of fluorescence in the HRP-containing hydrogel microstructures, with fluorescence intensity being a strong function of analyte concentration. The novel cell culture system with integrated sensing elements described here may be enhanced in the future by incorporating additional biorecognition elements to enable multi-metabolite detection at the site of a cell.
KW - Biosensors of extracellular metabolites
KW - Cell micropatterning
KW - Hyrogel microstructures
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U2 - 10.1016/j.bios.2009.01.029
DO - 10.1016/j.bios.2009.01.029
M3 - Article
C2 - 19251408
AN - SCOPUS:62649108797
SN - 0956-5663
VL - 24
SP - 2604
EP - 2610
JO - Biosensors and Bioelectronics
JF - Biosensors and Bioelectronics
IS - 8
ER -