PH nanosensor

Petersons pH probe also was modified in order to give a miniature fiber optic sensor potentially suitable for glucose measurements90. Kopelman et al.91 developed a fiber-optic pH nanosensor for physiological measurements using a dual-emission sensitive dye. The performance of a pH sensor was reported92. An unclad fiber was dip-coated with a thin layer of porous cladding within which a pH-sensitive dye was entrapped. The fundamental... 

It was demonstrated that poly(styrene-b/oc -vinylpyrrolidone) beads (0 220 nm) are suitable for preparation of pH nanosensors [12]. Various fluorescein derivatives were embedded and did not leach out of the beads due to functionalization with highly lipophilic octadecyl anchor. The pK., of the indicators inside the nanobeads varied from 5.8 to 7.7 making them suitable for various biotechnological, biological and marine applications. The beads based on a lipophilic l-hydroxypyrene-3,6, 8-trisulfonate (pKa 6.9) were also manufactured. 

Doussineau T, Tmpp S, Mohr GJ (2009) Ratiometric pH-nanosensors based on rhodamine-doped silica nanoparticles functionalized with anaphthalimide derivative. J Colloid Interface Sci 339 266-270... 

FIGURE 1.5 Amperometric response of an NO nanosensor upon addition of lOOnM NO and lpM oxyhemoglobin to a stirred 0.1 M phosphate buffer solution (pH 7.4). 

Clark HA, Kopelman R, Tjalkens R, Philbert MA (1999) Optical nanosensors for chemical analysis inside single living cells. 1. Optical nanosensors for chemical analysis inside single living cells. 2. Sensors for pH and calcium and the intracellular application of PEBBLE sensors. Anal Chem 71 4837 1843... 

Kneipp J, Kneipp H, Wittig B, Kneipp K (2010) Following the dynamics of pH in endosomes of live cells with SERS nanosensors. J Phys Chem C 114 7421... 

Brasuel, M., et ah. Production, characteristics and applications of fluorescent PEBBLE nanosensors potassium oxygen, calcium and pH imaging inside live cells. Sensors Mater 2002, 14, 309-338. 

Brasuel, M. Kopeknan, R. Aylott, J. W. Clark, H. Xu, H. Hoyer, M. Miller, T. J. Tjalkens, R. PhUbert, M. A. Production, characteristics and applications of fluorescent PEBBLE nanosensors potassium, oxygen, calcium and pH imaging inside live cells. Sens. Mater. 2002,14, 309-338. 

The sensing schemes described in this section may also be used for sensing other analytes that cause a change in pH. The preparation of nanosensors also is conceivable by coating single UCNPs with respective sensor chemistry. 

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