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Accession Number ADA583394
Title PH-Responsive Layer-by-Layer Nanoshells for Direct Regulation of Cell Activity.
Publication Date 2012
Media Count 14p
Personal Author I. Drachuk M. Lisunova N. Kelley-Loughnane O. Shchepelina S. Harbaugh
Abstract Saccharomyces cerevisiae yeast cells encapsulated with pH-responsive synthetic nanoshells from lightly cross-linked polymethacrylic acid showed a high viability rate of around 90%, an indication of high biocompatibility of synthetic pHresponsive shells. We demonstrated that increasing pH above the isoelectric point of the polymer shell leads to a delay in growth rate; however, it does not affect the expression of enhanced green fluorescent protein. We suggest that progressive ionization and charge accumulation within the synthetic shells evoke a structural change in the outer shells which affect the membrane transport. This change facilitates the ability to manipulate growth kinetics and functionality of the cells with the surrounding environment. We observed that hollow layer-by layer nanoshells showed a remarkable degree of reversible swelling/deswelling over a narrow pH range /201pH 5.0 6.0/202, but their assembly directly on the cell surface resulted in the suppression of large dimensional changes. We suggest that the variation in surface charges caused by deprotonation/protonation of carboxylic groups in the nanoshells controlled cell growth and cell function, which can be utilized for external chemical control of cell-based biosensors.
Keywords Biomimetics
Cells(Biology)
Crosslinking(Chemistry)
Fluorescence
Growth(General)
High rate
Ionization
Kinetics
Membranes
Ph factor
Proteins
Reprints
Shells(Structural forms)
Sizes(Dimensions)
Suppression

 
Source Agency Non Paid ADAS
NTIS Subject Category 57A - Anatomy
57S - Physiology
Corporate Author Georgia Inst. of Tech., Atlanta. School of Materials Science and Engineering.
Document Type Journal article
Title Note Journal article.
NTIS Issue Number 1401
Contract Number FA9550-11-1-0233 FA9550-09-1-0162

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