•A novel fluorescence probe with simple structure for relay recognition of Fe3+ and PO43− was synthesized.•The proposed method exhibited high selectivity and sensitivity, short respond time, low detection limit.•The fluorescence probe can also be used for biological cell imaging.A novel fluorescent probe XDS based on 4-methylumbelliferone and 2-picolylamine platforms has been designed and synthesized, which behaves fast relay recognition of Fe3+ and PO43− via a fluorescence “on−off−on” response signal. Probe XDS exhibited very high sensitivity and unique selectivity for Fe3+ over other common metal ions, and the detection limit of was 3.2 × 10−7 M. Moreover, the addition of the PO43− ions could cause the recovery of fluorescence. This relay recognition feature of probe XDS has potential applications in the determination of trace amount of Fe3+ and PO43− in environmental systems. Interestingly, fluorescence imaging experiments demonstrated that the probe XDS can also be used to monitoring the intracellular Fe3+ in RAMOS cells.Download high-res image (137KB)Download full-size image

The cloud points (CP) of aqueous solutions of two triblock copolymers, poly(ethylene glycol)–block-poly(propylene glycol)–block-poly(ethylene glycol), L31 (Mn = 1100 g·mol−1) and L61 (Mn = 2100 g·mol−1) were determined in the absence and presence of five salting out salts (K2SO4, K2CO3, KCl, KNO3, KBr) at different concentrations, and the liquid–liquid equilibrium (LLE) data for L31/L61–K2SO4/K2CO3/KCl/KNO3/KBr ATPSs were measured at 283.15 K. The results show that the addition of these salts decreases the CP of aqueous copolymer solutions and the copolymer with the higher molecular weight has a lower CP. The order in which salts depress the CP is as follows: \( {\text{K}}_{2} {\text{SO}}_{4} > {\text{K}}_{2} {\text{CO}}_{3} > {\text{KCl}} > {\text{KNO}}_{3} > {\text{KBr}} \). When the concentration of salt is the same, the anion order to depress the CP is as follows: \( {\text{SO}}_{4}^{2 - } > {\text{CO}}_{3}^{2 - } \), \( {\text{Cl}}^{ - } > {\text{NO}}_{3}^{ - } > {\text{Br}}^{ - } \). The abilities of the salt and anion to induce phase separations are in accord with their ability to reduce the CP. The results also show that the copolymer with the higher molecular weight phase separates more easily.

•Ethanol/NaH2PO4 ATPS was used for extraction and preliminary purification of GA.•The feasibility and efficiency of the ATPE of GA were proved.•Effects of ATPS compositions on the stability of GA were investigated.Aqueous two-phase extraction (ATPE) was employed for the extraction and preliminary purification of anthocyanins in grape juice (GA). The influences of such factors as the type and concentration of salt, the concentration of alcohol and the quantity of grape juice, extraction time, system pH and temperature were investigated to obtain the optimal extraction conditions. They were listed as follow: sodium dihydrogen phosphate (NaH2PO4) concentration 28% (w/w), ethanol concentration 25% (w/w), the quantity of grape juice 1 mL, temperature 298.15 K, time 1 h and no pH adjustment. Under the optimal conditions, the relative and absolute recovery of GA in the top phase reached 99.35% and 99.26% in one step, respectively, while the sugar-removing rate reached 75.08%. The results of Multistage and scale-up extractions showed that it could remain over 90% GA in the top phase and remove more than 90% sugars after continuous extraction for two times. Scale-up extractions and the GA stability results showed the effectiveness and great potential of this method in processing mass grape juice.Graphical abstract

In common sense, the chemical reaction between Cu2+ and S2− ions produces black precipitation of CuS. However, if they are separated by an eggshell, they produce copper with trace amount of CuS on the surface of the eggshell at the side of copper chloride solution within one week. Such an unexpected phenomenon strongly indicated that Cu2+ is able to be reduced into metal copper when S2− diffuses throughout the porous eggshell. The produced copper was verified by reacting with nitric acid to generate red-brown nitrogen dioxide at ambient temperature, as well as by the powder X-ray diffraction (XRD) and energy dispersive analysis of X-rays (EDS).