A novel kind of composite material for simultaneous luminescent determination of air pressure and temperature is presented. The dual sensor consists of a fluorinated platinum porphyrin complex (PtTFPP) as an oxygen‐sensitive probe, and of the highly temperature‐sensitive europium complex Eu(tta)3(dpbt) as temperature probe. Both are incorporated into different polymer microparticles to control response characteristics and to avoid interferences. Encapsulation of PtTFPP in poly(styrene‐co‐acrylonitrile) (PSAN) results in a broad dynamic range from 0.05 to 2.00 bar for pressure measurements. The europium complex was incorporated into poly(vinyl chloride) to reduce the cross sensitivity towards oxygen. This system represents a new class of luminescent sensor system, where the signals are separated via the different luminescence lifetimes of the indicators. It is possible to monitor the emission of the temperature‐sensitive probe by means of time‐resolved fluorescence imaging without interferences, because the luminescence lifetime of the temperature indicator is tenfold longer than that of the oxygen indicator. The temperature image can then be used to compensate cross sensitivity of the pressure indicator towards temperature. In combination with an appropriate time‐resolved measurement technique, this material enables simultaneous imaging of pressure (or oxygen partial pressure) and temperature distributions on surfaces. It is distinguished from other approaches of dual pressure and temperature sensitive paints because it avoids the need of signal separation by application of different cameras or by use of different optical filters or light sources.

Optical chemical sensors -with few exceptions -rely on the use of smart probes and materials that respond to the species of interest by change in their optical properties, often in luminescence. [1][2][3][4][5][6][7][8][9][10] They have the specific option of optical multiplexing. In other words, sensors can be designed so that they give a multitude of spectral and time-dependent information that, in turn, enables sensing of several parameters simultaneously if the signals can be separated and attributed in an unambiguous way. We and others [11][12][13][14][15][16] have previously designed dual sensors, for example for oxygen and temperature or oxygen and pH, and related multiplex approaches (with one probe responding to more than one parameter) have been reported recently. [17][18][19] Our interest in sensors for pH, temperature (T), and O 2 (in gaseous or dissolved forms) results from the fact that these are the parameters probably determined most often in chemistry, biology, environmental sciences, numerous industrial areas, and also in more specific areas such as clinical chemistry or marine sciences. Electrochemical devices that measure these parameters do exist, are widely distributed, and perform fairly well. Optical single sensors for these species have also existed for many years, [1] are less common, and have specific merits because information is gathered via photons rather than electrons, often in combination with fiber-optic light guides. This can substantially reduce the risk of explosions in chemical plants, enables sensing at patients with heart pacemakers and in strong electromagnetic fields, and -in case of fiber optics -paves the way to sensing over large distances.At first glance, it would appear that triple sensing can be achieved by simply using the three best working indicator probes (one each for pH, T, and O 2 ) with highly different optical spectra and to incorporate them into an appropriate polymer matrix, which is then exposed to the sample to be analyzed. A closer look into the situation reveals that the solution is not as simple for several reasons. Notably, the spectral overlap of practically all indicator probes results in substantial spectral crosstalk. In fact, most probes have bands that extend over more than 150 nm in width, so that the spectral range that can be exploited in practice (400-750 nm) is almost fully covered by two indicator dyes, not considering the fact that pH probes exist in two forms depending on pH. A second and quite serious limitation results from the effect of fluorescence resonance energy transfer (FRET) whenever indicator probes with overlapping bands are applied in high concentrations so that the critical distance for FRET to occur (typically 5-7 nm) is reached; this can result in heavy crosstalk of signals. Third, pH-dependent color changes are likely to lead to inner filter effects, which are disadvantageous if luminescence intensity (rather than lifetime) is measured. Finally, each of the three probes requires an optimized polymer matrix that not onl...

This review focuses on the application of novel technologies for generating biocompatible surfaces for high-throughput screening (HTS) of proteins. Various methods of coupling and spotting proteins on self-assembled monolayer (SAM) surfaces will be described along with the protein chip challenges pertaining to spot homogeneity, morphology, biocompatibility and reproducibility.

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Core-shell particles (CSPs) composed of a polystyrene core and a poly(vinyl pyrrolidone) shell were dyed with a luminescent platinum(ii) porphyrin probe for oxygen. In parallel, microparticles were dyed with a luminescent iridium(ii) complex acting as a probe for temperature. The particles were deposited (by spraying) on a surface to enable continuous imaging of the distribution of oxygen (and thus of barometric pressure) and temperature. Unlike most previous paints of this kind, a binder polymer is not needed and water can be used as a dispersant. This makes the paint environmentally friendly and reduces costs in terms of occupational health, clean-up, and disposal. Both indicator probes in the sensor paint can be excited at 405 nm using LEDs or diode lasers, whilst their emission maxima are spectrally separated by about 130 nm. Thus, two independent optical signals are obtained that allow for fluorescent imaging of barometric pressure (in fact oxygen partial pressure) and of temperature, and also to correct the oxygen signal for effects of temperature. The paint was calibrated at air pressures ranging from 50 mbar to 2000 mbar and at temperatures between 1 degrees C and 50 degrees C.