TY - JOUR A1 - Weigl, Stefan A1 - Wittmann, Elisabeth A1 - Rück, Thomas A1 - Bierl, Rudolf A1 - Matysik, Frank-Michael T1 - Effects of ambient parameters and cross-sensitivities from O2, CO2 and H2O on the photoacoustic detection of acetone in the UV region JF - Sensors Actuators B Chemical N2 - We present a sensitive UV LED photoacoustic setup for the detection of gaseous acetone and discuss its applicability towards breath analysis. We investigated the performance of the sensor for low acetone concentrations down to 0.1 parts per million (ppmV). The influences of temperature, flow, pressure, optical power and LED duty cycle on the measured signal have been examined. To gain a better understanding of the different effects on the photoacoustic signal, correlation analysis was applied and feature importance was determined using a large measured dataset. Furthermore, the cross-sensitivities towards O2, CO2 and H2O have been studied extensively. Finally, the sensor’s performance to detect acetone between 0.1–1 ppmV within gas mixtures simulating breath exhale conditions has been investigated, too. With a limit of detection (LoD) of 12.5 parts per billion (ppbV) (3σ) measured under typical breath exhale gas mixture conditions, the sensor demonstrated a high potential for the application of acetone detection in human breath analysis. KW - Acetone detection KW - Photoacoustic spectroscopy KW - High power UV LED KW - Cross-sensitivities KW - Acetone breath analysis Y1 - 2021 U6 - https://doi.org/10.1016/j.snb.2020.129001 SN - 0925-4005 N1 - Corresponding authors: Stefan Weigl, Elisabeth Wittmann, Thomas Rück, Rudolf Bierl, Frank-Michael Matysik N1 - Corrigendum to “Effects of ambient parameters and cross-sensitivities from O2, CO2 and H2O on the photoacoustic detection of acetone in the UV region” [Sens. Actuators B: Chem. 328 (February 2021) (2020) 129001]; https://doi.org/10.1016/j.snb.2020.129392 IS - 328 PB - Elsevier ER - TY - JOUR A1 - Wunderlich, Lukas A1 - Hausler, Peter A1 - Maerkl, Susanne A1 - Bierl, Rudolf A1 - Hirsch, Thomas T1 - Nanoparticle Determination in Water by LED-Excited Surface Plasmon Resonance Imaging JF - Chemosensors N2 - The increasing popularity of nanoparticles in many applications has led to the fact that these persistent materials pollute our environment and threaten our health. An online sensor system for monitoring the presence of nanoparticles in fresh water would be highly desired. We propose a label-free sensor based on SPR imaging. The sensitivity was enhanced by a factor of about 100 by improving the detector by using a high-resolution camera. This revealed that the light source also needed to be improved by using LED excitation instead of a laser light source. As a receptor, different self-assembled monolayers have been screened. It can be seen that the nanoparticle receptor interaction is of a complex nature. The best system when taking sensitivity as well as reversibility into account is given by a dodecanethiol monolayer on the gold sensor surface. Lanthanide-doped nanoparticles, 29 nm in diameter and with a similar refractive index to the most common silica nanoparticles were detected in water down to 1.5 mu g mL(-1). The sensor can be fully regenerated within one hour without the need for any washing buffer. This sensing concept is expected to be easily adapted for the detection of nanoparticles of different size, shape, and composition, and upon miniaturization, suitable for long-term applications to monitor the quality of water. KW - ENGINEERED NANOPARTICLES KW - imaging KW - nanoparticle KW - plasmon resonance KW - REFRACTIVE-INDEX KW - sensor KW - surface Y1 - 2021 U6 - https://doi.org/10.3390/chemosensors9070175 SN - 2227-9040 VL - 9 IS - 7 SP - 1 EP - 9 PB - MDPI ER - TY - CHAP A1 - Hausler, Peter A1 - Fischer, Johannes A1 - Wunderlich, Lukas A1 - Recum, Patrick A1 - Peller, Sebastian A1 - Hirsch, Thomas A1 - Bierl, Rudolf T1 - Miniaturisierte Sensoren basierend auf Oberflächenplasmonenresonanz, Chancen und Herausforderungen T2 - DGaO-Proceedings 2021 N2 - Derzeit gibt es zahlreiche Bereiche, wie Umwelt Monitoring und zivile Infrastruktur in denen geeignete Sensoren für die Überwachung der Systeme fehlen. SPR-basierte Sensoren haben das Potential diese Lücke zu schließen. Um für den Einsatz in der Umwelt tauglich zu werden, müssen die Sensoren noch robuster werden. Hier wird eine mögliche Lösung gezeigt. Y1 - 2021 UR - https://www.dgao-proceedings.de/download/122/122_a21.pdf PB - Dt. Gesellschaft für angewandte Optik CY - Erlangen-Nürnberg ER -