Article
Chemistry, Physical
Anthony V. Sica, Ash Sueh Hua, Helen H. Lin, Ellen M. Sletten, Timothy L. Atallah, Justin R. Caram
Summary: We demonstrate a method called Spectrally selective Time-resolved Emission through Fourier-filtering (STEF) for separating and resolving the dynamics of multiple emitters without using conventional filters. Our approach utilizes a fixed path-length imbalanced Mach-Zehnder interferometer to interfere and cancel (or enhance) specific spectral signatures corresponding to one emissive species. We show the range and utility of STEF by performing various procedures, including filtering laser scatter, separating fluorescence lifetimes, and resolving overlapping fluorescent stains.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Multidisciplinary Sciences
Bishnubrata Patra, Manvendra Sharma, William Hale, Marcel Utz
Summary: The study utilized a micro-NMR platform to observe metabolic changes in a single spheroid culture of human cancer cells, revealing interesting findings such as linear monitoring of cell numbers and differences in metabolic rates between spheroids and monolayer cultures.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Multidisciplinary
Junyao Wang, Xingyu Chen, Huan Liu, Yunpeng Li, Tianhong Lang, Rui Wang, Bowen Cui, Weihua Zhu
Summary: This paper presents a helical three-dimensional passive micromixer fabricated through 3D printing and polymer dissolution technology, which effectively improves the mixing efficiency according to experimental results.
Review
Chemistry, Multidisciplinary
Danya Lyu, Jinchang Xu, Zhenyou Wang
Summary: Understanding the structure-activity relationship of catalysts and the dynamic of electrocatalytic reactions is essential for designing efficient systems. In situ vibrational spectroscopy provides a unique tool for decoding molecular-level factors involved in electrocatalysis. This review summarizes time-resolved in situ infrared and Raman techniques and their applications in electrocatalytic research, highlighting the importance of capturing dynamic processes and transient information.
FRONTIERS IN CHEMISTRY
(2023)
Article
Optics
Alberto Ghezzi, Armin J. M. Lenz, Fernando Soldevila, Enrique Tajahuerce, Vito Vurro, Andrea Bassi, Gianluca Valentini, Andrea Farina, Cosimo D'Andrea
Summary: In this work, we propose a time-resolved multispectral fluorescence microscopy system based on the Single-Pixel Camera (SPC) scheme, which achieves high resolution and short measurement time using Compressive Sensing (CS) technology. Data Fusion (DF) with a high-resolution camera is used to address the low spatial resolution issue typical of SPC. By integrating hardware and algorithms, this system reduces the number of measurements while preserving the information content, allowing for a zoom feature without moving the optical system. The system is characterized in terms of spatial, spectral, and temporal properties, and is validated on a cellular sample.
Review
Chemistry, Multidisciplinary
Jiani Ma, Tina Jingyan Miao, Junwang Tang
Summary: The article explores the application of transient absorption spectroscopy (TAS) and time-resolved infrared (TRIR) spectroscopy in a wide range of heterogeneous photocatalytic systems, demonstrating the various ways in which these techniques can be used to understand the correlation between materials design, charge carrier behavior, and photocatalytic activity.
CHEMICAL SOCIETY REVIEWS
(2022)
Article
Chemistry, Multidisciplinary
Inseong Choi, Guk-Young Ahn, Eun Seo Kim, Se Hee Hwang, Hyo-Jung Park, Subin Yoon, Jisun Lee, Youngran Cho, Jae-Hwan Nam, Sung-Wook Choi
Summary: A new microfluidic bioreactor was developed with fibrous micromixers for ingredient mixing and a long macrochannel for in vitro transcription reaction, enabling continuous production of mRNA. The diameter of the fibrous microchannels in the micromixers was controlled by using an electrospun microfibrous disc with different microfiber diameters. The micromixer with larger diameter fibrous microchannels showed superior mixing performance. The continuous reaction in the microfluidic bioreactor with efficient mixing performance can serve as a powerful platform for various microfluidic reactions.
Article
Multidisciplinary Sciences
Te Ma, Tetsuya Inagaki, Satoru Tsuchikawa
Summary: This study developed a time-resolved transmittance spectroscopic method to validate the light scattering changing characteristics in kiwifruit during shelf-life and in cold storage conditions, and successfully formulated a mathematical model to classify the stages of kiwifruit softening.
SCIENTIFIC REPORTS
(2023)
Article
Instruments & Instrumentation
Kacper Grodecki, Krzysztof Murawski
Summary: This article presents a new data treatment method based on time-resolved photoluminescence, acting as a streak camera for infrared. An experiment and analysis of the time-resolved photoluminescence spectrum for the HgCd0.33Te0.67 sample at 120K were conducted, along with typical measurements to compare the results with literature. An interpretation of the behavior for three different time constants found in the signal is proposed.
APPLIED SPECTROSCOPY
(2021)
Article
Nanoscience & Nanotechnology
Yu Chen, Xiang Chen, Wentian Lai, Qihao Zhu
Summary: This study presents an oscillatory-flow-based microfluidic mixer (OFBMM) that utilizes a gas bubble and periodically changed pressure to achieve oscillatory motion of fluids. The results show that increasing the pressure and gas bubble volume can promote fluid mixing. Additionally, the OFBMM demonstrates potential applications in the field of biochemical analysis.
Article
Physics, Multidisciplinary
Andrew H. Proppe, Kin Long Kelvin Lee, Alexander E. K. Kaplan, Matthias Ginterseder, Chantalle J. Krajewska, Moungi G. Bawendi
Summary: Solid-state single-photon emitters (SPEs) are limited by spectral diffusion. We develop a framework to simulate PCFS correlation functions from diffusing spectra and train a machine learning model to accurately reconstruct noisy correlations. This enables PCFS to extract optical coherence times on previously inaccessible timescales.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Analytical
Dongbin Su, Kaikai Li
Summary: This study explores the feasibility of ink diffusion based on Raman spectra monitoring and identifies ink types using OPLS-DA multivariate modeling. The kinetics of ink diffusion can be elucidated by the interplay of chromatographic effects and diffusion equilibrium. The OPLS-DA model demonstrated 100% accuracy in differentiating between all types of stamp inks, affirming the significant potential of Raman spectroscopy for forensic science applications.
MICROCHEMICAL JOURNAL
(2023)
Article
Optics
Dongqiao Zheng, Wei Li, Benyang Zhao, Zhao Yang, Li Xia
Summary: This study demonstrates a SERS detection system with all-fiber connection, combined with a microfluidic chip and micro-lenses, to improve system stability and detected signal intensity. It lays the foundation for the development of a rapid and portable SERS system and real-time recognition in future optical fiber system design.
Article
Neurosciences
Alexander Avian, Christian Mattersberger, Lukas Schober, Johann Martensen, Martin Wolf, Wataru Kamo, Gerhard Pichler, Bernhard Schwaberger, Berndt Urlesberger
Summary: This study aimed to analyze the precision of time-resolved near-infrared spectroscopy (t-NIRS) measurements of cerebral oxygenation in preterm infants. The results showed low within-patient variation, indicating high precision of the measurement.
Article
Chemistry, Analytical
Mojtaba Zeraatkar, Marco D. de Tullio, Gianluca Percoco
Summary: The demand for accessible and affordable microfluidic devices has led to the development of new manufacturing methods like 3D printing to replace traditional techniques. Through fused filament fabrication (FFF) 3D printing, microfluidic micromixers were created to address the challenge of enhancing the mixing process in microfluidic devices. A design of experiment demonstrated the impact of different parameters on mixing performance in printed devices, showing the inherent property of ridges formed on microchannels due to the FFF process.
Article
Engineering, Biomedical
Vedran Nedelkovski, Orestis G. Andriotis, Karin Wieland, Christoph Gasser, Andreas Steiger-Thirsfeld, Johannes Bernardi, Bernhard Lendl, Michael L. Pretterklieber, Philipp J. Thurner
Summary: Bone tissue has unique mechanical properties due to its complex hierarchical structure. Testing of bone structures at the microscale using techniques like FIB and AFM has shown the importance of water for bone mechanics and the potential increase in bone fragility with age, linked to decreased energy dissipation.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2022)
Article
Instruments & Instrumentation
Christopher K. Akhgar, Vanessa Nuernberger, Marlene Nadvornik, Victoria Ramos-Garcia, Isabel Ten-Domenech, Julia Kuligowski, Andreas Schwaighofer, Erwin Rosenberg, Bernhard Lendl
Summary: This study presents a novel method for determining the fatty acid composition of human milk using mid-infrared spectroscopy. By analyzing the absorbance spectra of pure milk fat recorded via attenuated total reflection Fourier transform infrared spectroscopy and combining the results with gas chromatography-mass spectrometry measurements, multivariate regression equations were established to predict fatty acid concentrations. The method achieved good predictions for various important fatty acid parameters, demonstrating its high accuracy.
APPLIED SPECTROSCOPY
(2022)
Article
Instruments & Instrumentation
Dominik Wacht, Mauro David, Borislav Hinkov, Hermann Detz, Andreas Schwaighofer, Bettina Baumgartner, Bernhard Lendl
Summary: The study presents the development of a mesoporous zirconia coating on ATR crystals to address the chemical stability issues of mesoporous silica in alkaline aqueous solutions, enabling in situ monitoring of organic pollutants. The coating exhibits strong chemical stability and high enrichment performance, with low detection limits for benzonitrile and valeronitrile.
APPLIED SPECTROSCOPY
(2022)
Article
Chemistry, Analytical
Alicja Dabrowska, Mauro David, Stephan Freitag, Aaron Maxwell Andrews, Gottfried Strasser, Borislav Hinkov, Andreas Schwaighofer, Bernhard Lendl
Summary: Mid-infrared chemical sensors based on quantum cascade technology were developed for broadband detection of aqueous samples targeting bovine milk proteins. The setup combined a tunable quantum cascade laser with a spectrally tailored in-house fabricated quantum cascade detector, showing similar performance to a high-end FTIR spectrometer. The study highlights the potential of quantum cascade detectors in next-generation MIR liquid-phase chemical sensors with low noise and high dynamic range.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Chemistry, Analytical
Christopher K. Akhgar, Julian Ebner, Oliver Spadiut, Andreas Schwaighofer, Bernhard Lendl
Summary: In this study, an external cavity-quantum cascade laser-based mid-infrared spectrometer was used for in-line monitoring of proteins from preparative ion-exchange chromatography. Advanced background compensation strategies were implemented to obtain high-quality protein spectra, showing the potential to replace laborious off-line methods for protein monitoring.
ANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Analytical
Daniel R. Hermann, Georg Ramer, Markus Kitzler-Zeiler, Bernhard Lendl
Summary: Vibrational circular dichroism (VCD) is a powerful technique for determining the absolute configuration of molecules. This study presents an improved setup for VCD measurement using an external cavity quantum cascade laser as a light source, which allows for faster measurements with competitive noise levels. The setup offers higher temporal resolution and shorter measurement times compared to traditional methods.
ANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Analytical
Shilpa Vijayakumar, Jeremy Rowlette, Andreas Schwaighofer, Bernhard Lendl
Summary: The stability of high-concentration protein formulations is a significant challenge in biopharmaceutical development. This study used laser-based mid-infrared spectroscopy to investigate the effect of protein concentration and the presence of sugars on the thermal denaturation of bovine serum albumin (BSA). The results showed that high BSA concentrations led to lower denaturation temperatures, while different sugars had both stabilizing and destabilizing effects.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
A. Catarina V. D. dos Santos, Nikolaus Hondl, Victoria Ramos-Garcia, Julia Kuligowski, Bernhard Lendl, Georg Ramer
Summary: Researchers have found that the application of conventional IR microscopy in the life sciences is limited due to the restrictions on spatial resolution. The use of AFM-IR technology allows for chemical analysis of biomolecules at the nanoscale, which can contribute to the investigation of nano and microscale biological processes.
ACS MEASUREMENT SCIENCE AU
(2023)
Article
Instruments & Instrumentation
Daniel-Ralph Hermann, Georg Ramer, Lisa Riedlsperger, Bernhard Lendl
Summary: Recently, high-throughput quantum cascade laser-based vibrational circular dichroism (QCL-VCD) technology has significantly reduced the measurement time for high-quality vibrational circular dichroism spectra. This study evaluated the feasibility of using QCL-VCD for chiral monitoring in a circulating system. The results showed that QCL-VCD demonstrated good sensitivity to both molar and enantiomeric excess (EE), making it suitable for high-resolution chiral monitoring in chemical processes.
APPLIED SPECTROSCOPY
(2023)
Article
Physics, Applied
E. V. Bergmann, G. V. B. Lukasievicz, B. Lendl, A. R. Sampaio, V. S. Zanuto, M. L. Baesso, L. C. Malacarne, N. G. C. Astrath
Summary: An all-optical photoinduced lensing method for exciting and monitoring acoustic waves in liquids is introduced in this article. The method utilizes a laser pulse to generate a localized temperature gradient, which launches pressure waves in the liquid at a nanosecond timescale. The refractive index change caused by acoustic and thermal effects can be sensed by a probe laser beam. The physical properties of the liquids can be quantitatively described based on the theoretical description of the intensity signal.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Plant Sciences
Jessica C. Huss, Sebastian J. Antreich, Martin Felhofer, Konrad Mayer, Michaela Eder, Ana Catarina Vieira Dias dos Santos, Georg Ramer, Bernhard Lendl, Notburga Gierlinger
Summary: The water caltrop develops unique woody fruits with unusually large seeds among aquatic plants. Hydrolyzable tannins flood the endocarp tissue during fruit development and lignin is integrated into the cell walls during maturation. The presence of ester linkages in the mature tissue suggests that gallotannins and their derivatives are cross-linked to other wall components, leading to unique cell-wall properties.
Article
Chemistry, Analytical
Ivan Rienda, Erika Moro, Alvaro Perez-Rubio, Ramon Trullenque-Juan, David Perez-Guaita, Bernhard Lendl, Julia Kuligowski, Jose V. Castell, Judith Perez-Rojas, Eugenia Pareja, Guillermo Quintas
Summary: Near-infrared and attenuated total reflectance-Fourier transform mid-infrared spectroscopy can be used for real-time quantitative assessment of liver steatosis, playing a crucial role in the success of liver transplantation surgery.
Article
Chemistry, Analytical
Ivan Rienda, Isabel Ten-Domenech, Erika Moro, Marta Moreno-Torres, Judith Perez-Rojas, Eugenia Pareja, Alvaro Perez-Rubio, Ramon Trullenque, Ramiro Jover, Bernhard Lendl, David Perez-Guaita, Julia Kuligowski, Jose V. Castell, Guillermo Quintas
Summary: The assessment of liver steatosis is crucial in hepatology and liver transplantation surgery. Current methods for evaluating steatosis are time-consuming, subjective, and lack reproducibility. Recent research has shown that infrared spectroscopy could be used for real-time quantification of steatosis during abdominal surgery. This study developed and validated digital image analysis methods that provide accurate and reproducible reference values for steatosis quantification, enhancing the performance of infrared spectroscopic models. A PLS model in the 1810-1052 cm(-1) region using first derivative ATR-FTIR spectra provided RMSECV = 0.99%.
Article
Biochemical Research Methods
Florian Pilat, Benedikt Schwarz, Bettina Baumgartner, Daniela Ristanic, Hermann Detz, Aaron M. M. Andrews, Bernhard Lendl, Gottfried Strasser, Borislav Hinkov
Summary: Quality control of liquids plays a crucial role in analytical chemistry, and the gold standard for measuring residual water in organic solvents and pharmaceutical applications is Karl Fischer titration. A high-performance lab-on-a-chip sensor based on mid-IR spectroscopy is proposed for real-time analysis of residual water concentration in isopropyl alcohol. Two experiments demonstrate its ability to detect water content with high sensitivity and rapid response time. The sensor achieves a limit of detection between 120 ppm and 150 ppm for the flow cell configuration and 1.5 x 10(-2)%(vol) to 19%(vol) in the in situ configuration.
Article
Chemistry, Analytical
A. Catarina V. D. dos Santos, Davide Tranchida, Bernhard Lendl, Georg Ramer
Summary: The routine analysis of polymer blends at the nanoscale usually requires electron microscopy techniques. The tapping mode AFM-IR, a recent technique that combines AFM's resolution with chemical information, is useful for analyzing highly heterogeneous samples.
