Design of Miniature Ultrawideband Active Magnetic Field Probe Using Integrated Design Idea.

This article presents a miniature ultrawideband active magnetic probe which is composed of a passive structure and an active amplification circuit structure. The active circuit mainly contains two chips, specifically an amplification chip (HMC797APM5E) and a power management chip (HMC980LP4E). The maximum size of the probe is no more than 64 × 41.5 mm2. Compared with the passive probe with the same-sized loop, the sensitivity of the proposed probe is enhanced by 25 dB through the active circuit design. The working frequency bandwidth of the proposed probe can cover 9 kHz to 18 GHz. Additionally, the flatness is about ±4 dB in terms of |S21| in the stable working bandwidth. It is efficient for high-frequency near-field scanning.

Endoplasmic Reticulum-Targeting Two-Photon Fluorescent Probe for CYP1A Activity and Its Imaging Application in Endoplasmic Reticulum Stress.

Cytochrome P450 1A is one of the vital subfamilies of heme-containing cytochrome P450 enzymes belonging to an important exogenous metabolizing CYP in human. The abnormal of endoplasmic reticulum (ER) may directly affect the functional activity of ER-located CYP1A and be associated with the occurrence and development of various diseases. In the present study, we constructed a selective two-photon fluorescent probe ERNM for rapid and visual detection of endogenous CYP1A that was localized in the ER. ERNM could target the ER and detect the enzymatically active CYP1A in living cells and tissues. The monitoring ability of ERNM for the fluctuations in functionality level of CYP1A was confirmed using ER stressed A549 cell. Based on the ER-targeting two-photon probe for CYP1A, the close association of ER state and the functional activity of ER-locating CYP1A was confirmed, which would promote the deep understanding of the biofunction of CYP1A in various ER-related diseases.

High-speed multiparametric imaging through off-resonance tapping AFM with active probe.

Off-resonance tapping (ORT) mode of atomic force microscopy (AFM), based on force-distance curve, is widely concerned due to its advantages of weak tip-sample interaction and concurrent quantitative property mapping. However, the ORT-AFM still has the disadvantage of slow scan speed caused by low modulation frequency. In this paper, we overcome this disadvantage by introducing active probe method. With active probe, the cantilever was directly actuated with the induced strain after applying voltage in the piezoceramic film. In this way, the modulation frequency could be increased to more than an order of magnitude faster than that of traditional ORT, thus improving the scan rate. We demonstrated high-speed multiparametric imaging with the active probe method in ORT-AFM.

Research progress of active probes targeting specific aminoacids / 药学学报

Activity-based protein (proteomic) profiling (ABPP) has emerged as a key component of the broad field of chemical techniques capable of directly analyzing enzyme activity in living systems. With the deepening of research on electrophilic warheads and nucleophilic amino acids, and the continuous proposal and improvement of effective development strategies, the application of amino acid-targeting active probes in various biological systems has facilitated the identification, development of new targets in various disease contexts and discovery of inhibitors. The purpose of this review is to summarize the latest progress in the design and application of active probes targeting specific amino acids, in order to provide support for the further development of amino acid-targeted covalent inhibitordrugs.