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Improving Robustness, Sensitivity and Simplicity of Potentiometric Sensors Through Symmetry and Conceptual Design
It is an enormous challenge to bring chemical sensing concepts from a controlled laboratory setting into the field while maintaining accuracy. In an environment of uncontrolled, fluctuating temperatures and a lack of repeated calibration, sensor reliability can rapidly deteriorate the accuracy. Today, many sensing concepts are explored for home use or as wearable sensors, and it is paramount to understand and optimize the chemistry for reliable measurements to become possible. This review focuses on the well-established class of potentiometric sensors, mostly known for the measurement of pH, with a range of electrolytes, and how conceptual advances can be used to make them as robust and sensitive as possible. While drawing from recent work of the group at the University of Geneva, the importance of symmetry is stressed to minimize the influence of temperature. The development of self-powered sensing systems that no longer require a battery is explained. This is then connected to protocols in which the sensitivity of these sensors can be reliably improved beyond that dictated by the Nernst equation
Portable and Handheld Raman Instruments Open a Multitude of Applications
Fundamental science can sometimes take a long time until it is useful for practical applications, as was the case for Raman spectroscopy. For a long time, it lacked powerful excitation sources and sensitive detectors. However as technology evolved, the number of exciting applications has boomed. Modern Raman spectroscopy has significant advantages, especially in sample preparation. Handheld Raman devices can be very compact and therefore be easily taken to the sample instead of bringing the sample to the lab. Non-destructive measurements obviously are important in gemmology and mineralogy, even in space. In the field of archaeology, pigments in precious ancient paintings, scrolls or books can be identified. This application is also used to identify fraud and falsification and in studies from a medical school they have reported that Raman spectroscopy can be applied to distinguish cancerous tissue from healthy tissue. Due to the mobility and ruggedness of the handheld hardware, Raman spectroscopy can be used for police, firefighters, and military applications for identification of explosives and illicit drugs or warfare substances. With SERS (Surface Enhanced Raman Spectroscopy), Raman spectroscopy can even be used for trace analysis. The SERS effect enhances the sensitivity of the Raman signal by a factor of up to 107. This enables, for example, measuring pesticide residuals on fruit or vegetable surfaces for food safety. It can also be used to identify traces of drugs, e.g. in urine. However, one of the most common Raman-applications is the identity check or verification of incoming goods (RMID) in the pharma industries, directly in the warehouse. Users appreciate the ease of use and the ruggedness of the Raman hardware
The openBIS Digital Platform for Instrumentation and Data Workflow in the Analytical Laboratory
The management of scientific data plays a key role in all research areas and has increased in importance. Providing researchers with customizable data management tools is crucial for effectively managing data according to the FAIR principles. These principles have been defined by Wilkinson et al. in 2016, which describe how scientific data should be managed.[1] To support the specific needs of researchers at Empa, openBIS[2] was chosen as a FAIR compliant data management platform. OpenBIS is an Electronic Laboratory Notebook (ELN) and Laboratory Information Management System (LIMS) developed at ETH. The commissioning of this platform for the case of an analytical chemistry lab presented multiple challenges. In this paper, solutions to adapt openBIS as a digital platform to integrate the laboratory data workflow in chemical analysis and for spectroscopy instruments are presented. Two laboratory projects as case studies are described, consisting of a data pipeline and a complex dashboard for data collection, visualization and interaction. These examples show a successful integration of the data management platform in accordance with the FAIR data guidelines along with maximizing efficiency for laboratory personnel
Miniaturization of MALDI Mass Spectrometers with the Technological Breakthrough of the Digital Ion Trap: Peptide and Protein Analysis in MS1, MS2, and MS3
A digital ion trap (DIT) mass spectrometer was developed to extend the mass range in comparison to conventional ion traps. This was achieved by changing the RF voltage from a sinusoidal to a rectangular waveform. In addition to the extended mass range, the size of the instrument was miniaturized. To show the benefits of this development, MALDI applications in MS1, MS2, and MS3 are presented: On one hand, it is possible to analyze intact proteins, on the other hand the instrument enables insights into the structure of antibodies and glycoproteins after enzymatic digestion and collision-induced dissociation (CID)