Open Access

Molecularly imprinted polymers (MIPs) containing fluorescent probe monomers or crosslinkers that are covalently polymerized into the MIP network are powerful tools for the direct indication of analytes in a sample or a sample extract [1]. This direct incorporation not only allows the use of the diverse formats in which MIPs can be prepared for analytical applications but also allows the use of MIPs for real-time signal readout as well as for enrichment and readout, depending on the design of the assay. In addition, the presence of a dye in each step of the preparation process, starting with the prepolymerization mixture, provides a useful tool for monitoring the synthetic procedure to determine whether the intended complexes are being imprinted and/or whether unexpected or undesirable events are occurring during preparation. Naturally, in addition to the general requirement that such a functional dye must survive the polymerization process, the intended application and desired format must also take various factors into account before a specific dye scaffold is selected, i.e., the wavelength range of operation, the type of signal changes to be measured, possible internal referencing as well as possible multiplexing. Based on our experience in the development of fluorescent probe monomers and crosslinkers [2–5], this contribution offers (young) researchers a guide to selecting the appropriate dye for their MIP.

Reactive extrusion (REx) is emerging as a powerful technology for the continuous and solventless production of modified lignins. However, the optimization of REx-based processes for modifying lignin relies on offline lignin analytics, which are time-consuming and heavily influenced by sample preparation. This study integrated near- infrared (NIR) spectroscopy into a twin-screw extruder to monitor in real time the modification of softwood kraft lignin via esterification with octenyl succinic anhydride (OSA). The NIR data was processed by means of chemometric methods. Temperature and screw configuration were found to influence the esterification of lignin. Combining these results with offline lignin analytics, 120 ◦ C was selected as the optimal temperature in conjunction with the integration of kneading elements into the screw profile, to yield OSA-lignin esters with ≥ 50% degree of modification. The product output was successfully scaled up sevenfold while using NIR spectroscopy to monitor the extrusion. In addition, the broader applicability of this inline monitoring method was demonstrated by using a biorefinery lignin from hardwood. The target degree of modification was achieved with minimal recalibration of process parameters. A space–time yield of up to 7 x 10 •day was realized, indicating the potential of this REx process for industrial adoption. Overall, this work provides a foundation for the development of a process analytical technology for monitoring lignin modification during REx that can be expanded to other lignin chemistries, thus providing scalable and adaptable solutions for adding value to lignin.

The analysis of paper-based food contact materials (FCM) has gained increasing attention due to the widespread use of per- and polyfluoroalkyl substances (PFAS) and their known toxic effects and environmental persistence. As regulatory frameworks for PFAS in FCM remain limited, sensitive and reliable analytical methods are necessary to ensure food safety. While PFAS analysis is predominantly performed using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), a systematic development of gas chromatography coupled to mass spectrometry (GC-MS)-based methods for multiple PFAS classes remains limited. In this study, two pre-column derivatization techniques were optimized and evaluated for GC-MS determination of perfluoroalkyl carboxylic acids (PFCA), fluorotelomer alcohols (FTOH), and fluorotelomer carboxylic acids (FTCA). Both derivatization methods enabled qualification and quantification of the targeted PFAS with comparable limits of detection in the low ng/mL range. N,N-Dimethylformamide dimethyl acetal (DMFDMA) derivatization proved to be more sensitive with a limit of detection down to 0.85 ng/mL. In addition, this derivatization approach was successfully automated within the GC-MS workflow, resulting in sample preparation times comparable to those of LC-MS-based methods. The application of this optimized method to paper-based FCM demonstrated its suitability for real world FCM analysis. Results of PFAS content per targeted PFAS of 26.6 to 261.4 ng/g highlight the potential of GC-MS analysis, particularly when combined with automated derivatization, as a viable alternative or complement to LC-MS for PFAS analysis in FCM.

We present a fully coupled, patient-specific 3D–0D computational framework for hearts supported with left ventricular assist devices (LVAD) that enables controlled in silico experimentation. The approach monolithically integrates three-dimensional CFD of the left ventricle (LV), left atrium (LA), aortic root, and LVAD cannulae with a closed-loop 0D lumped parameter network of the full circulation. Mitral and aortic valve dynamics are governed by transvalvular pressure and flow with patient-specific regurgitant orifice areas, and the LVAD is represented via a pressure–flow (H–Q) relation. This manuscript provides the complete mathematical formulation, coupling strategy, and parameterization required to build a reproducible pipeline from dynamic CT, 2D transthoracic echocardiography, and right heart catheterization. This methodology is demonstrated in a patient under long-term support of LVAD and concomitant mitral and aortic regurgitation. The personalized, fully coupled 3D–0D models reproduced available clinical targets with a mean error of 8.6%, enabling controlled in silico interrogation of valve repair strategies. In the patient-specific state, simulated mitral and aortic regurgitant volumes were 6.6 and 6.5 mL per cycle, yielding a forward cardiac output of 3.16 L/min despite an LVAD flow of 3.7 L/min. In silico isolated mitral valve (MV) repair, isolated aortic valve (AV) repair, and combined MV+AV repair increased forward output to 3.41, 3.33, and 3.55 L/min, respectively; however, aortic valve opening and increased aortic pressure pulsatility (up to 38.9 vs. 13.5 mmHg) were observed only when MV repair was involved. These left-sided improvements propagated through the cardiopulmonary circulation, reducing pulmonary pressures and right ventricular loading, with the largest benefit observed following combined repair. We show that the modeling platform presented provides a powerful means to study mechanical circulatory support, enabling patient-specific evaluation of surgical interventions in patients with LVAD and delivering quantitative insight into clinically important metrics—such as aortic pulsatility, RV afterload, and chamber-level flow patterns.

Over the past three decades, luminescent nanocrystals have evolved from a scientific curiosity into a versatile class of functional materials with applications spanning photonics, bioimaging, sensing, energy conversion, and quantum technologies. Throughout this development, Markus Haase has played a defining role in shaping the field through his pioneering contributions to colloidal semiconductor quantum dots and, in particular, lanthanide-doped upconverting nanocrystals. His work established fundamental synthetic strategies, provided mechanistic insight into particle formation and optical processes, and set new standards for reproducibility, characterization, and scientific rigor. This commemorative lecture brings together the perspectives of colleagues, former doctoral researchers, collaborators, and long-standing friends from the scientific community to celebrate Markus Haase's remarkable career and lasting scientific legacy. Beyond highlighting key milestones and breakthroughs, the presentation reflects on the qualities that have distinguished his work: intellectual curiosity, creativity, uncompromising scientific integrity, and the willingness to pursue challenging and unconventional research directions. Equally important, it acknowledges the personal values that have inspired generations of researchers—his honesty, loyalty, commitment, passion for science, and distinctive sense of humor. Together, these contributions have not only advanced the field of luminescent nanocrystals but have also left a lasting impact on the people and collaborations that continue to shape it.