Nanopore analysis is a powerful technique for single molecule analysis by virtue of its electrochemically confined effects. As a single molecule translocates through the nanopore, the featured ionic current pattern on the time scale contains single molecule characteristics including volume, charge, and conformational properties. Although the characteristics of a single molecule in a nanopore have been written to the featured ionic current, extracting the dynamic information from a complex current trace is still a big challenge. Here, we present an applicable nanopore analysis method employing the Hilbert-Huang Transform (HHT) to study the vibrational features and interactions of a single molecule during the dynamic translocation process through the confined space of a nanopore. The HHT method is specially developed for analyzing nonlinear and non-stationary data that is highly compatible with nanopore data with a high frequency resolution. To provide proof-of-concept, we applied HHT to measure the frequency response for the wild-type (WT) aerolysin and mutant K238E aerolysin nanopores with and without the presence of poly(dA)4, respectively. The energy-frequency-time distribution spectra demonstrate that the biological nanopore contributes greatly to the characteristics of the high frequency component (>2 kHz) in the current recording. Our results suggest that poly(dA)4 undergoes relatively more consistent and confined interactions with K238E than WT, leading to a prolonging of the duration time. Therefore, the characteristics in frequency analysis could be regarded as an "single-molecule ionic spectrum" inside the nanopore, which encodes the detailed behaviours of single-molecule weak interactions.
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http://dx.doi.org/10.1039/c8fd00023a | DOI Listing |
Biomaterials
January 2025
Center for AIE Research, Guangdong Provincial Key Laboratory of New Energy Materials Service Safety, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China; School of Science and Engineering, Shenzhen Institute of Aggregate Science and Technology, The Chinese University of Hong Kong, Shenzhen (CUHK-Shenzhen), Guangdong, 518172, China. Electronic address:
Multimodal phototheranostics on the basis of single molecular species shows inexhaustible and vigorous vitality, particularly those emit fluorescence in the second near-infrared window (NIR-II), the construction of such exceptional molecules nonetheless retains formidably challenging. In view of the undiversified molecular skeletons and insufficient phototheranostic outputs of previously reported NIR-II fluorophores, herein, electron acceptor engineering based on heteroatom-inserted rigid-planar pyrazinoquinoxaline was manipulated to fabricate aggregation-induced emission (AIE)-featured NIR-II counterparts with donor-acceptor-donor (D-A-D) architecture. Systematical investigations substantiated that one of those synthesized AIE molecules, namely 4TPQ, incorporating a fused thiophene acceptor, synchronously exhibited high molar absorptivity (ε), NIR-II emission, typical AIE tendency, significant reactive oxygen species (ROS) generation, and high photothermal conversion efficiency.
View Article and Find Full Text PDFJ Agric Food Chem
January 2025
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Characteristic Plant Extraction Laboratory, Functional Molecules Analysis and Biotransformation Key Laboratory of Universities in Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, People's Republic of China.
One new azaphilone derivative () from in ordinary medium, one new phthalide derivative (), a microbial transformation product of ingredients by , a pair of new austdiol enantiomers (+)- and (-)-, one new epsilon-caprolactone derivative (), and one new ophiobolin-type sesterterpenoid () from the in host medium were reported. The structures were determined by spectroscopic analysis and single-crystal X-ray diffraction. Compounds - could completely inhibit the germination of rice seeds at 50 μg/mL, which is higher than that of the positive control.
View Article and Find Full Text PDFClin Pharmacol Drug Dev
January 2025
Chimerix, Inc., Clinical Pharmacology and Translational Medicine, Durham, NC, USA.
Dordaviprone (ONC201) is a novel, small molecule imipridone with antitumor effects in glioma patients. This study evaluated the pharmacokinetics and safety of dordaviprone following single escalating doses (Part A), as a capsule content mixed with applesauce or Gatorade (sports drink) [Part B1]), and with or without food [Part B2]. The most common treatment-emergent adverse events pooled across study parts (Parts A, B1, and B2) were headache, dizziness, and headache, respectively; all were mild.
View Article and Find Full Text PDFFront Parasitol
April 2024
Institut für Parasitologie, Biomedizinisches Forschungszentrum Seltersberg (BFS), Justus Liebig Universitaet Giessen, Giessen, Germany.
Introduction: Schistosomiasis has for many years relied on a single drug, praziquantel (PZQ) for treatment of the disease. Immense efforts have been invested in the discovery of protein kinase (PK) inhibitors; however, given that the majority of PKs are still not targeted by an inhibitor with a useful level of selectivity, there is a compelling need to expand the chemical space available for synthesizing new, potent, and selective PK inhibitors. Small-molecule inhibitors targeting the ATP pocket of the catalytic domain of PKs have the potential to become drugs devoid of (major) side effects, particularly if they bind selectively.
View Article and Find Full Text PDFTheranostics
January 2025
Division of Cancer Biology, Laboratory Animal Center, Fourth Military Medical University, Xi'an, Shaanxi 710032, China.
Bone metastasis and skeletal-related complications are primary causes of mortality in advanced-stage prostate cancer (PCa). Epigenetic regulation, particularly histone modification, plays a key role in this process; however, the underlying mechanisms remain elusive. In mouse models, JARID1D was an important mediator of both visceral and bone metastases.
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