One-pot hydrothermal synthesis of Si-doped carbon quantum dots with up-conversion fluorescence as fluorescent probes for dual-readout detection of berberine hydrochloride.

Here, the high fluorescent silicon-doped carbon quantum dots (Si-CQDs) were prepared by a facile and one-pot hydrothermal assay using 3-aminopropyltrimethoxysilane as the carbon and silicon source. The prepared Si-CQDs exhibit favorable water-soluble, high-temperature resistance, acid resistance, alkali resistance, high ionic strength resistance, high photostability, film-forming ability and solid-state fluorescence. Compared to other Si-CQDs that have been reported, the prepared Si-CQDs show unique up-conversion fluorescence. Furthermore, it is found that berberine hydrochloride (BH) can effectively quench the down- and up-conversion fluorescence of the Si-CQDs, making it can be used as a highly sensitive and specific probe for BH dual-mode sensing. Meanwhile, the linear range of down-conversion fluorescence detection for BH is 0.5-30.0 µmol/L with a limit of detection (LOD) of 50 nmol/L, and the linear range of up-conversion fluorescence assay for BH is 0-25.0 µmol/L. The mechanism of down-conversion fluorescence quenching by BH was investigated through a series of studies. The results show the quenching mechanism is the inner filter effect (IFE). Moreover, this proposed strategy has been well used to analyze BH in urine samples with satisfactory results.

[Therapeutic effect of the combined treatment with acupuncture and venlafaxine hydrochloride on depression based on diffusion tensor imaging technology].

OBJECTIVE: To explore the effectiveness and safety of the combined treatment with acupuncture and venlafaxine hydrochloride on depression in terms of the microstructure change of white matter fiber tracts of brain based on diffusion tensor imaging technology (DTI). METHODS: The prospective study design was adopted. All of 60 patients with depression were randomized into an acupuncture-medication group and a medication group, 30 cases in each one. In the medication group, venlafaxine hydrochloride was used, 75 mg per day in the 1st week, 150 mg per day in the 2nd week and 225 mg per day from the 3rd to 6th week. In the acupuncture-medication group, on the base of the treatment in the medication group, acupuncture was combined. Baihui (GV 20) and Yintang (GV 29) were the main acupoints. The supplementary acupoints were selected according to the clinical symptoms of individuals. The needles were retained for 30 min. Acupuncture was provided once every 2 days, 3 times a week. The consecutive 12 weeks of treatment were required in the two groups. Additionally, a normal group was prepared with 30 healthy volunteers. Separately, before treatment, in 2, 8 and 12 weeks of treatment, Hamilton's depression scale (HAMD-17), Beck depression inventory scale (BDI) and the antidepressant side effect scale (SERS) were adopted to evaluate the effectiveness and safety of the two groups. Moreover, before and after 12 weeks of treatment, DTI was adopted to detect the fractional anisotropy score (FA) of each brain region in the patients. RESULTS: After treatment, the scores of HAMD-17 and BDI were all reduced in the two groups (P<0.05). In 8 and 12 weeks of treatment, the scores of HAMD-17 and BDI in the acupuncture-medication group were less than those in the medication group (P<0.05). The difference in SERS score was not significant statistically between the two groups (P>0.05). Compared with the healthy volunteers, FA scores in 6 brain regions changed obviously in the patients with depression, including the white matter of bilateral frontal lobes, splenium of corpus callosum, left cingulated gyrus, white matter of bilateral inferior temporal gyrus, white matter of bilateral inferior parietal lobe and white matter of bilateral deep temporal occipital region separately. Before treatment, the differences in FA scores of these 6 brain regions were not significant statistically between the two groups (P>0.05). After treatment, FA scores in the white matter of bilateral frontal lobes, white matter of bilateral inferior temporal gyrus and white matter of bilateral deep temporal occipital region in the acupuncture-medication group were all higher than those in the medication group (P<0.05). CONCLUSION: Acupuncture repairs the brain white matter fiber tracts in some brain regions to certain extent and the therapeutic effects are enhanced with the adjuvant medication of venlafaxine hydrochloride.

One-Pot Hydrothermal Synthesis of Carbon Dots with Efficient Up- and Down-Converted Photoluminescence for the Sensitive Detection of Morin in a Dual-Readout Assay.

Blue luminescent carbon dots (CDs) with a high photoluminescence (PL) quantum yield (48.3 ± 5.3%) were prepared by the one-pot hydrothermal reaction of citric acid with poly(ethylenimine) (PEI). The CDs display bright PL, narrow emission spectra, pH-dependent PL intensity, high photostability, and up-converted luminescence. The CDs exhibit a quenching of both down- and up-conversion PL in the presence of morin and thus serve as useful probes for morin detection. Both down- and up-conversion measurements allow the quantification of concentrations from 0 to 300 µmol/L with a detection limit of 0.6 µmol/L, and this dual-mode detection increases the reliability of the measurement. The proposed method of determination is simple, sensitive, and cost-effective, with potential applications in clinical and biochemical assays.

High Sensitive and Selective Detection of PFOS with Resonance Light Scattering Technology Based on the Interaction with Victoria Blue B.

This report presents a simple, sensitive and selective victoria blue B (VBB)-based resonance light scattering (RLS) assay of perfluorooctane sulfonate (PFOS). In pH 6.0 KH2PO4-NaOH buffer solution, VBB can be protonated and reacts with PFOS through electrostatic interactions to produce ionic-association complexes. Simultaneously, the interaction leads to enhanced resonance light scattering intensities greatly, which are characterized with a peak at 277 nm. It is found that the enhanced RLS intensity is proportional to the concentration of PFOS in a range of 0.05 to 4.0 µmol·L-1. The limit of detection is 5.0 nmol·L-1. While, under the optimal experimental conditions, almost no change of the resonance light scattering intensity was observed between VBB and perfluorooctane acid (PFOA) which is one kind of representative perfluorinated compounds (PFCs). The excellent selectivity of PFOS could be due to the hydrophobicity of PFOS higher than PFOA. It is worth noting that the proposed method is capable of differentiating PFOS and some other PFCs. UV/Vis absorption spectrum and scanning electron microscope (SEM) image both were investigated to further validate the reaction mechanism. The interference of coexisting foreign substances and the optimum tests of reaction conditions, including pH value, reaction time, experimental temperature and ionic strength, were also investigated. This method has been successfully applied to the determination of PFOS in environmental water samples with RSD ≤1.74%. The experimental process as followed: In 2 mL colorimetric tube, 200 µL pH 6.0 KH2PO4-NaOH buffer solution, followed by adding 600 µL 20 µmol·L-1 VBB solution, swirl evenly, then add the right amount of PFOS solution. After vortex mixing with ultrapure water volume to 2 mL, swirl to mix, stand for 10 min at room temperature. Then the mixture was transferred for RLS measurements and absorption measurement.