A General Photonic Crystal Sensing Motif: Creatinine in Bodily Fluids
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- 作者：Anjal C. Sharma ; Tushar Jana ; Rasu Kesavamoorthy ; Lianjun Shi ; Mohamed A. Virji ; David N. Finegold ; and Sanford A. Asher
- 刊名：Journal of the American Chemical Society
- 出版年：2004
- 出版时间：March 10, 2004
- 年：2004
- 卷：126
- 期：9
- 页码：2971 - 2977
- 全文大小：185K
- 年卷期：v.126,no.9(March 10, 2004)
- ISSN：1520-5126
文摘
We developed a new sensing motif for the detection and quantification of creatinine, which is animportant small molecule marker of renal dysfunction. This novel sensor motif is based on our intelligentpolymerized crystalline colloidal array (IPCCA) materials, in which a three-dimensional crystalline colloidalarray (CCA) of monodisperse, highly charged polystyrene latex particles are polymerized within lightly cross-linked polyacrylamide hydrogels. These composite hydrogels are photonic crystals in which the embeddedCCA diffracts visible light and appears intensely colored. Volume phase transitions of the hydrogel causechanges in the CCA lattice spacings which change the diffracted wavelength of light. We functionalizedthe hydrogel with two coupled recognition modules, a creatinine deiminase (CD) enzyme and a 2-nitrophenol(2NPh) titrating group. Creatinine within the gel is rapidly hydrolyzed by the CD enzyme in a reaction whichreleases OH-. This elevates the steady-state pH within the hydrogel as compared to the exterior solution.In response, the 2NPh is deprotonated. The increased solubility of the phenolate species as compared tothat of the neutral phenols causes a hydrogel swelling which red-shifts the IPCCA diffraction. This photoniccrystal IPCCA senses physiologically relevant creatinine levels, with a detection limit of 6 
M, at physiologicalpH and salinity. This sensor also determines physiological levels of creatinine in human blood serumsamples. This sensing technology platform is quite general. It may be used to fabricate photonic crystalsensors for any species for which there exists an enzyme which catalyzes it to release H+ or OH-.
M, at physiologicalpH and salinity. This sensor also determines physiological levels of creatinine in human blood serumsamples. This sensing technology platform is quite general. It may be used to fabricate photonic crystalsensors for any species for which there exists an enzyme which catalyzes it to release H+ or OH-.