Enzyme-Free and Amplified Fluorescence DNA Detection Using Bimolecular Beacons

In this work, we propose a simple and enzyme-free strategy for sensitive and selective DNA detection by using two different types of molecular beacons (MBs), MB1 and MB2. In this method, the target DNA binds with and restores the fluorescence of MB1 first. Then, MB2 hybridizes with MB1 and free the target, which is used to trigger another reaction cycle. The cycling use of the target and the employment of bi-MBs amplify the fluorescence intensity for sensitive DNA detection. The detection limit of this method was obtained as 10 pM, which is about 2 orders of magnitude sensitive than the conventional MB-based approaches

DataSheet1_Bio-inspired aptamers decorated gold nanoparticles enable visualized detection of malathion.docx

Biosensors always respond to the targets of interest in a specific manner, employing biological or bio-mimic recognition elements such as antibodies and aptamers. Inspired by target recognition in nature, an aptamer-mediated, gold nanoparticle-based sensing approach is developed in this work for effective determination of malathion. The sensing system consists of negatively charged aptamer probes, and polycationic proteins, protamine, as well as exceptional colorimetric nanoprobes, barely gold nanoparticles (AuNPs). Protamine molecules bound to aptamer probes hinder the aggregation of AuNPs, while no such inhibition is maintained when aptamer-specific malathion is introduced into the solution, thus leading to the solution colour change from red to blue observable by the naked eye. The assay is accomplished via a mix-and-measure step within 40 min with a detection limit as low as 1.48 μg/L (3σ/s rule). The assay method also exhibits high selectivity and good applicability for the quantification of malathion in tap water with recovery rates of 98.9%–109.4%. Additionally, the good detection accuracy is also confirmed by the high-performance liquid chromatography method. Therefore, the non-enzymatic, label- and device-free characteristics make it a robust tool for malathion assay in agricultural, environmental, and medical fields.</p

DataSheet1_Tuftsin: A Natural Molecule Against SARS-CoV-2 Infection.docx

Coronavirus disease 2019 (COVID-19) continuously progresses despite the application of a variety of vaccines. Therefore, it is still imperative to find effective ways for treating COVID-19. Recent studies indicate that NRP1, an important receptor of the natural peptide tuftsin (released from IgG), facilitates SARS-CoV-2 infection. Here, we found 91 overlapping genes between tuftsin targets and COVID-19-associated genes. We have demonstrated that tuftsin could also target ACE2 and exert some immune-related functions. Molecular docking results revealed that tustin could combine with ACE2 and NRP1 in stable structures, and their interacted regions cover the binding surfaces of S1-protein with the two receptors. Using surface plasmon resonance (SPR) analysis, we confirmed that tuftsin can bind ACE2 and NRP1 directly. Importantly, using SPR-based competition assay we have shown here that tuftsin effectively prevented the binding of SARS-CoV-2 S1-protein to ACE2. Collectively, these data suggest that tuftsin is an attractive therapeutic candidate against COVID-19 and can be considered for translational as well as clinical studies.</p

Adaptive Bayesian algorithm for achieving desired quantum transition

Bayesian methods which utilize Bayes' theorem to update the knowledge of desired parameters after each measurement, are used in a wide range of quantum science. For various applications in quantum science, efficiently and accurately determining a quantum transition frequency is essential. However, the exact relation between a desired transition frequency and the controllable experimental parameters is usually absent. Here, we propose an efficient scheme to search the suitable conditions for a desired quantum transition via an adaptive Bayesian algorithm, and experimentally demonstrate it by using coherent population trapping in an ensemble of laser-cooled $^{87}$Rb atoms. The transition frequency is controlled by an external magnetic field, which can be tuned in realtime by applying a d.c. voltage. Through an adaptive Bayesian algorithm, the voltage can automatically converge to the desired one from a random initial value only after few iterations. In particular, when the relation between the target frequency and the applied voltage is nonlinear, our algorithm shows significant advantages over traditional methods. This work provides a simple and efficient way to determine a transition frequency, which can be widely applied in the fields of precision spectroscopy, such as atomic clocks, magnetometers, and nuclear magnetic resonance

Calibration plots, LOD and LOQ for the 5 compounds.

<p>^a<i>y</i> and <i>x</i> were, respectively, the peak areas and masses (μg) of the analytes.</p><p>^b LOD was defined as the mass for which signal-to-noise ratio was 3 and the LOQ was defined as the mass for which the signal-to-noise ratio was 10.</p><p>Calibration plots, LOD and LOQ for the 5 compounds.</p

Typical chromatograms and ratio chromatograms of 27 batches of CBAT samples at 5 wavelengths, as well as the chromatograms of marker compound standards.

<p>The chromatograms: (A) 250 nm (B) 360 nm (C) standards, the ratio chromatograms: (D) 250 nm (E) 360 nm.</p

The TCM/HM quality grades classified by SQRFM.

<p>The TCM/HM quality grades classified by SQRFM.</p

Monitoring and Evaluating the Quality Consistency of Compound Bismuth Aluminate Tablets by a Simple Quantified Ratio Fingerprint Method Combined with Simultaneous Determination of Five Compounds and Correlated with Antioxidant Activities

<div><p>A combination method of multi-wavelength fingerprinting and multi-component quantification by high performance liquid chromatography (HPLC) coupled with diode array detector (DAD) was developed and validated to monitor and evaluate the quality consistency of herbal medicines (HM) in the classical preparation Compound Bismuth Aluminate tablets (CBAT). The validation results demonstrated that our method met the requirements of fingerprint analysis and quantification analysis with suitable linearity, precision, accuracy, limits of detection (LOD) and limits of quantification (LOQ). In the fingerprint assessments, rather than using conventional qualitative “Similarity” as a criterion, the simple quantified ratio fingerprint method (SQRFM) was recommended, which has an important quantified fingerprint advantage over the “Similarity” approach. SQRFM qualitatively and quantitatively offers the scientific criteria for traditional Chinese medicines (TCM)/HM quality pyramid and warning gate in terms of three parameters. In order to combine the comprehensive characterization of multi-wavelength fingerprints, an integrated fingerprint assessment strategy based on information entropy was set up involving a super-information characteristic digitized parameter of fingerprints, which reveals the total entropy value and absolute information amount about the fingerprints and, thus, offers an excellent method for fingerprint integration. The correlation results between quantified fingerprints and quantitative determination of 5 marker compounds, including glycyrrhizic acid (GLY), liquiritin (LQ), isoliquiritigenin (ILG), isoliquiritin (ILQ) and isoliquiritin apioside (ILA), indicated that multi-component quantification could be replaced by quantified fingerprints. The Fenton reaction was employed to determine the antioxidant activities of CBAT samples <i>in vitro</i>, and they were correlated with HPLC fingerprint components using the partial least squares regression (PLSR) method. In summary, the method of multi-wavelength fingerprints combined with antioxidant activities has been proved to be a feasible and scientific procedure for monitoring and evaluating the quality consistency of CBAT.</p></div

PCA score plot (A) and loading plot (B) of 27 batches of CBAT samples on the basis of the contents of the 5 marker compounds.

<p>PCA score plot (A) and loading plot (B) of 27 batches of CBAT samples on the basis of the contents of the 5 marker compounds.</p