G-quadruplexes (G4s) are of vital biological significance and G4-specific ligands with conformational selectivity show great application potential in disease treatment and biosensing. RHAU, a RNA ...helicase associated with AU-rich element, exerts biological functions through the mediation of G4s and has been identified to be a G4 binder. Here, we investigated the interactions between the RHAU peptide and G4s with different secondary structures using size exclusion chromatography (SEC) in association with circular dichroism (CD), ultraviolet-visible (UV-Vis) absorption, and native polyacrylamide gel electrophoresis (Native-PAGE). Spectral results demonstrated that the RHAU peptide did not break the main structure of G4s, making it more reliable for G4 structural analysis. The RHAU peptide was found to display a structural selectivity for a preferential binding to parallel G4s as reflected by the distinct chromatographic retention behaviors. In addition, the RHAU peptide exhibited different interactions with intermolecular parallel G4s and intramolecular parallel G4s, providing a novel recognition approach to G4 structures. The findings of this study enriched the insight into the binding of RHAU to G4s with various conformations. It is noteworthy that SEC technology can be easy and reliable for elucidating G4-peptide interactions, especially for a multiple G4 coexisting system, which supplied an alternative strategy to screen novel specific ligands for G4s.
Drug combination therapies employing dual-drug delivery systems offer an effective approach to reduce disadvantages of single-drug therapy, such as high dose and easy generation of drug resistance. ...Herein, a dual-drug delivery system based on nanogel-incorporated injectable hydrogel (NHG) was designed for sequential local delivery of combretastatin-A4 phosphate (CA4P) and doxorubicin (DOX) for antiangiogenesis and anticancer combination therapy. The injectable hydrogel was prepared for loading and quick release of hydrophilic drug CA4P, while the pH and redox stimuli-responsive nanohydrogels were incorporated into the injectable hydrogel by pH-responsive boronate ester bond for sustained long-term DOX delivery. The dual-drug-loaded NHG system released CA4P and DOX sequentially and exhibited high inhibitory activities on the cancer cell proliferation in vitro. It displayed superior therapeutic efficacy in vivo with only one single injection. Immunohistochemistry analyses suggested a synergistic therapeutic effect through tumor vascular collapse caused by CA4P and tumor cell apoptosis induced by DOX. The combination therapy of antiangiogenic and cytotoxic drugs using NHG delivery system offers a promising approach for improved cancer therapeutic efficacy. The nanogel-embedded injectable hydrogel can be employed as a universal drug carrier for local dual-drug delivery with sequential release behaviors by simple injection.
Degradation of the kinetically trapped bulk heterojunction film morphology in organic solar cells (OSCs) remains a grand challenge for their practical application. Herein, we demonstrate highly ...thermally stable OSCs using multicomponent photoactive layer synthesized via a facile one-pot polymerization, which show the advantages of low synthetic cost and simplified device fabrication. The OSCs based on multicomponent photoactive layer deliver a high power conversion efficiency of 11.8% and exhibit excellent device stability for over 1000 h (>80% of their initial efficiency retention), realizing a balance between device efficiency and operational lifetime for OSCs. In-depth opto-electrical and morphological properties characterizations revealed that the dominant PM6-b-L15 block polymers with backbone entanglement and the small fraction of PM6 and L15 polymers synergistically contribute to the frozen fine-tuned film morphology and maintain well-balanced charge transport under long-time operation. These findings pave the way towards the development of low-cost and long-term stable OSCs.
ObjectiveTo improve the prediction and early warning ability of the customs supervision department on the safety risk of imported alcohol， ensure food safety in China， and accelerate the efficiency ...of customs clearance， a fuzzy comprehensive evaluation model of imported alcohol safety risk based on analytic hierarchy process and risk matrix was constructed.MethodsBased on the expert investigation results， the weight of each index was determined using the analytic hierarchy process， and the fuzzy membership matrices were obtained using the risk matrix. Subsequently， the risk value of each index was obtained using a fuzzy comprehensive algorithm. Simultaneously， a dynamic adjustment factor was introduced to finally realize the risk grade evaluation of specific batches of imported alcohol.ResultsThe safety risk level of imported alcohol for China was medium. Among the analyzed items， methanol had the highest risk value （82.917）， while natamycin had the lowest risk value （52.083）.ConclusionThe recommended detecti
It is widely acknowledged that casein is an important allergenic protein in milk which may cause danger to customers. The identification and confirmation of caseins through mass spectrometry requires ...the selection of suitable characteristic peptides. In this study, by means of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), the three most representative specific peptides of caseins in cow milk were screened out with mass-to-charge ratios (
/
) of 830, 1195, and 1759, respectively. By comparing 2,5-dihydroxybenzoic acid (DHB) and
-cyano-4-hydroxycinnamic acid (CHCA) MALDI matrices, it was found that DHB was more suitable for peptide detection with the limits of detection (LODs) of 0.1 mg/L for
,
-casein. Furthermore, on the basis of verifying the characteristic peptides of casein from cow milk, this protocol was applied to goat milk authentication. Cow milk addition in goat milk was investigated by using the screened specific peptides. The results showed that the adulteration could be identified when the proportion of cow milk was 1% or more. When applied to inspect adulteration in five brands of commercial goat milk, specific peptides of bovine casein were detected in four of them. The method has the advantages of strong reliability, high throughput, simple preprocessing, and fast speed, which can provide powerful help for prewarning dairy allergen.
► We model PD and HPD courses for comparatively disclosing the photodegradation mechanism of MG. ► In PD course, less ROS mainly transformed MG into MGCB, which was further decomposed into DLBP. ► In ...HPD course, more ROS enhanced the transformation of MG into MGCB and decomposition of MGCB into DLBP. ► After 0.5min irradiation, different routes to the discoloration of MG was evaluated and compared during PD and HPD courses. ► The degradation mechanism was also enlightened for AOP-based degradation of MG.
In this research, we choose photolysis degradation (PD) course and H2O2-enhanced PD (HPD) course using UV–vis light from two microwave-powered electrodeless discharge lamps (MPEDL-2) as simplified models. The results verified that (1) ∼70% and 99.7% of MG were removed in PD and HPD courses within 5min irradiation, and PD course was proved to be dependent on OH and O2-, (2) major routes were related to transformation of MG into malachite green carbinol base (MGCB), which could be further decomposed into 4-dimethylaminobenzophenone (DLBP), and (3) after 0.5min irradiation, PD course verified that ∼30% and 1% of MG was converted into MGCB and DLBP; for comparison, HPD course demonstrated that ∼12.9% and 28.5% of MG was transformed into MGCB and DLBP. Accordingly, we draw conclusions that degradation mechanism of MG could be revised as seven steps with MGCB as a key product and pH variation of aqueous dyes solution played minor role. Additionally, these conclusions were also enlightened for degradation of MG by advanced oxidation process.
A competitive colloidal gold lateral flow strip was developed, evaluated, and used as a quick, sensitive, low-cost and convenient tool to identify the authenticity of goat milk on the market. By ...mixing cow milk with goat milk and testing, the detection range and sensitivity of the strip method were obtained. The effect of boiling and hydrolysis to strip were evaluated. The detection of α-casein and β-casein from cow and their hydrolysate by strip were also finished. Based on UPLC-Q-Exactive Orbitrap MS and the casein antibody affinity column, the purified peptides was identified by Peaks software. The identified peptides were artificially synthesized and tested by strips. The results showed that the limit of detection for qualitative judgment of goat milk adulteration was, by the naked eye, 1.2 mg/100 g and the cut-off value was 6 mg/100 g. The boiling and hydrolysis process had no effect to detection. At the same time, α-casein and β-casein could be detected, indicating this method could not distinguish and
