Simultaneous and sensitive detection of multiple small biological molecules by microfluidic paper-based analytical device integrated with zinc oxide nanorods.

In this work, ZnO nanorods (ZnO NRs) with different sizes were hydrothermally grown on the surface of Whatman filter paper for the fabrication of a microfluidic paper-based device (µPAD) for the simultaneous detection of glucose and uric acid. As dual enzymatic reaction was employed for the colorimetric detection in this µPAD, the presence of ZnO NRs promoted the enzyme immobilization thus significantly enhancing the colorimetric signal. The coffee ring effect was effectively conquered by the uniform distribution of ZnO NR as well as a specialized double-layered µPAD design. Meanwhile, two color indicators with distinct colors were used to provide complementary results to better quantify the concentration of the analytes by naked eye. As a result, two linear calibration curves were obtained for the detection of glucose (0.01-10 mmol L-1) and uric acid (0.01-5 mmol L-1), along with a LOD of 3 µmol L-1 for glucose and 4 µmol L-1 for uric acid, respectively. The practical usefulness of the proposed µPAD was further validated by the simultaneous analysis of glucose and uric acid in serum samples and urine samples.

The biogeochemical characteristics of phosphorus in coastal sediments under high salinity and dredging conditions.

The geochemistry of phosphorus (P) can usually be related to prevailing environmental conditions. To investigate sedimentary P cycling mechanism and biogeochemical characteristics under high salinity and dredging conditions in polluted coastal sediments, thirty-three surface sediment samples were collected from the Jiehe River (JH), Jiaolai River (JL) and their estuarine and offshore areas in the Bohai Sea. Analyses included the Standards, Measurements and Testing method (SMT), Ivanoff organic P (OP) fractionation, and nuclear magnetic resonance (31P-NMR) of soluble P and indicated that HCl-P was the dominant fraction in sediments under high salinity stress. However, under dredging conditions in freshwater river sediments, NaOH-P was the dominant fraction. The potential activity of the OP fraction was reactive in freshwater river sediments, while it was unreactive under high salinity conditions. NaOH-P and HCl-P were found to be mainly derived from anthropogenic inputs, whereas both in-situ biological and anthropogenic inputs were important sources of the OP fractions. High salinity had the potential to increase NaOH-P content in acidic river sediments, resulting in the OP being relatively stable with a low risk level. Sediment dredging potentially increased the regeneration of P from HCl-P and OP and increased the potential activity of OP and IP. Seawater was found to induce removal of the NaOH-P and OP from offshore sediments, resulting in the regeneration of the remaining P at a low level.

Effects of lüfukang capsules on coronary artery ligation-induced arrhythmia in dogs.

OBJECTIVE: To observe the effects of Lüfukang Capsules on arrhythmia induced by ligation of coronary artery in dogs. METHODS: Thirty dogs were randomly divided into 5 groups, the model group administrated with equal volume of distilled water, the positive control group administrated with Wenxin Granules, and the small, medium and large dosage LFKC groups, 6 dogs in each group. Thirty minutes after medication, electrocardiogram was conducted and the time of arrhythmia occurrence, times of ventricular premature beat (VP), and incidence rates of ventricular tachycardia (VT) and ventricular fibrillation (VF) were recorded in the model dogs with arrhythmia induced by ligation of coronary artery. RESULTS: Compared with the model group, the occurrence time of arrhythmia induced by the coronary artery ligation in the medium and large LFKC groups was significantly delayed (20.45 +/- 9.10 and 19.92 +/- 3.78, respectively, both P < 0.05). The frequency of VP in the medium and large LFKC groups was also significantly decreased (8.17 +/- 6.62 and 3.83 +/- 2.79, respectively, both P < 0.01). CONCLUSION: LFKC has anti-arrhythmic effects for the experimental arrhythmia induced by the ligation of coronary artery in dogs.