In biological systems, the pH in intracellular organelles or tissues is strictly regulated, and differences of pH are deeply related to key biological events such as protein degradation, intracellular trafficking, renal failure, and cancer. Ratiometric fluorescence imaging is useful for determination of precise pH values, but existing fluorescence probes have substantial limitations, such as inappropriate p K for imaging in the physiological pH range, inadequate photobleaching resistance, and insufficiently long excitation and emission wavelengths. Here we report a versatile scaffold for ratiometric fluorescence pH probes, based on asymmetric rhodamine. To demonstrate its usefulness for biological applications, we employed it to develop two probes. (1) SiRpH5 has suitable p K and water solubility for imaging in acidic intracellular compartments; by using transferrin tagged with SiRpH5, we achieved time-lapse imaging of pH in endocytic compartments during protein trafficking for the first time. (2) Me-pEPPR is a near-infrared (NIR) probe; by using dextrin tagged with Me-pEPPR, we were able to image extracellular pH of renal tubules and tumors in situ. These chemical tools should be useful for studying the influence of intra- and extracellular pH on biological processes, as well as for in vivo imaging.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/jacs.8b00277 | DOI Listing |
Biosens Bioelectron
January 2025
Key Laboratory of Laboratory Medical Diagnostics, Ministry of Education, Department of Laboratory Medicine, Chongqing Medical University, Chongqing, China. Electronic address:
Isothermal amplification-based nucleic acid detection technologies have become rapid and efficient tools for molecular diagnostics. Sequence-specific monitoring methods are crucial for isothermal amplification, as they help identify the occurrence of extended primer dimers, which can lead to false positive results. Fluorescent aptamers are promising tools for real-time monitoring of isothermal amplification but are inherently limited by thermostability.
View Article and Find Full Text PDFBiophys Chem
January 2025
Department of Chemical and Biological Sciences, S. N. Bose National Centre for Basic Sciences, Kolkata 700106, India. Electronic address:
Quantitative characterization of protein conformational landscapes is a computationally challenging task due to their high dimensionality and inherent complexity. In this study, we systematically benchmark several widely used dimensionality reduction and clustering methods to analyze the conformational states of the Trp-Cage mini-protein, a model system with well-documented folding dynamics. Dimensionality reduction techniques, including Principal Component Analysis (PCA), Time-lagged Independent Component Analysis (TICA), and Variational Autoencoders (VAE), were employed to project the high-dimensional free energy landscape onto 2D spaces for visualization.
View Article and Find Full Text PDFBr J Hosp Med (Lond)
January 2025
Cardio-Oncology Centre of Excellence, Royal Brompton Hospital, London, UK.
The burdens of cardiovascular (CV) diseases and cardiotoxic side effects of cancer treatment in oncology patients are increasing in parallel. The European Society of Cardiology (ESC) 2022 Cardio-Oncology guidelines recommend the use of standardized risk stratification tools to determine the risk of cardiotoxicity associated with different anticancer treatment modalities and the severity of their complications. The use of the Heart Failure Association-International Cardio-Oncology Society (HFA-ICOS) is essential for assessing risk prior to starting cancer treatment, and validation of these methods has been performed in patients receiving anthracyclines, human epidermal receptor 2 (HER2)-targeted therapies and breakpoint cluster region-abelson oncogene locus (BCR-ABL) inhibitors.
View Article and Find Full Text PDFPathogens
January 2025
Laboratory of Parasitology, Military Institute of Hygiene and Epidemiology, 01-001 Warsaw, Poland.
Despite the vast amount of water on Earth, only a small percent is suitable for consumption, and these resources are diminishing. Moreover, water resources are unevenly distributed, leading to significant disparities in access to drinking water between countries and populations. Increasing consumption and the expanding human population necessitate the development of novel wastewater treatment technologies and the use of water treatment byproducts in other areas, such as fertilisers.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Department of Food Measurement and Process Control, Institute of Food Science and Technology, Hungarian University of Agriculture and Life Sciences (MATE), Somlói út 14-16., H-1118 Budapest, Hungary.
The processing of beans begins with a particularly time-consuming procedure, the hydration of the seeds. Ultrasonic treatment (US) represents a potential environmentally friendly method for process acceleration, while near-infrared spectroscopy (NIR) is a proposedly suitable non-invasive monitoring tool to assess compositional changes. Our aim was to examine the hydration process of red kidney beans of varying sizes and origins.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!