TY  - JOUR
A1  - Ast, Cindy
A1  - Schmälzlin, Elmar
A1  - Löhmannsröben, Hans-Gerd
A1  - van Dongen, Joost T.
T1  - Optical oxygen micro- and nanosensors for plant applications
JF  - Sensors
N2  - Pioneered by Clark's microelectrode more than half a century ago, there has been substantial interest in developing new, miniaturized optical methods to detect molecular oxygen inside cells. While extensively used for animal tissue measurements, applications of intracellular optical oxygen biosensors are still scarce in plant science. A critical aspect is the strong autofluorescence of the green plant tissue that interferes with optical signals of commonly used oxygen probes. A recently developed dual-frequency phase modulation technique can overcome this limitation, offering new perspectives for plant research. This review gives an overview on the latest optical sensing techniques and methods based on phosphorescence quenching in diverse tissues and discusses the potential pitfalls for applications in plants. The most promising oxygen sensitive probes are reviewed plus different oxygen sensing structures ranging from micro-optodes to soluble nanoparticles. Moreover, the applicability of using heterologously expressed oxygen binding proteins and fluorescent proteins to determine changes in the cellular oxygen concentration are discussed as potential non-invasive cellular oxygen reporters.
KW  - oxygen sensor
KW  - biosensors
KW  - microsensors
KW  - nanosensors
KW  - endogenous sensor proteins
KW  - dual-frequency phase-modulation
KW  - phosphorescence quenching
KW  - plant science
Y1  - 2012
U6  - https://doi.org/10.3390/s120607015
SN  - 1424-8220
VL  - 12
IS  - 6
SP  - 7015
EP  - 7032
PB  - MDPI
CY  - Basel
ER  -