Secondary metal doped cuprous-cyanoimidazole frameworks for triple-mode detection of dopamine.

BACKGROUNDS: Metal-organic framework-based nanozymes enable several opportunities for designing novel analysis methods for the detection of pesticides, heavy metal ions, and biomolecules; however, practical applications are still limited by a complicated synthesis route, lower catalytic activity, and single detection mode. Dopamine (DA) is a crucial catecholamine substance in the human body that acts as a neurotransmitter regulating a variety of physiological functions of the central nervous system. Therefore, it is highly significant to explore simple nanozymes synthesis methods for constructing a multiple analysis system to detection DA. RESULTS: Herein, we elaborately selected cobalt ions as the secondary metal doping in cuprous-cyanoimidazole frameworks (CuCo-CIFs) with a mass-production strategy. CuCo-CIFs possess intrinsic peroxidase-like activity that can convert hydrogen peroxide into various reactive oxygen species (i.e., 1O2, OH·, O2·-) and thereby oxidize colorless 3,3',5,5'-tetramethylbenzidine (TMB) and DA to blue oxTMB and orange polydopamine (PDA), respectively. The absorption of the detection system increases at 460 nm while decreases at 652 nm as the concentration of DA increases under near-neutral pH (6.1), resulting in a color transition from blue to orange. Consequently, an unprecedented triple-mode analysis system of DA monitored by naked eyes, ratiometric-absorption, and scanometric was constructed. The limit of detection for the ratiometric-absorption and scanometric mode can reach 20 nM and 28 nM, respectively. CuCo-CIFs were successfully used for the rapid and accurate detection of DA in practical samples. SIGNIFICANCE: As a simple, low-cost, multi-mode colorimetric platform, this kind of nanozyme detection with peroxidase-like activity exhibits significant potential for the detection of DA. Our work not only expands the applications of MOFs in analytical fields but also addresses the general challenges faced by nanozyme-based colorimetric detection systems of DA. This work provides valuable insights for the rational application of nanozyme and the design of new analysis systems.

[Glucocorticoid combined with ulinastatin in treatment of Kawasaki disease in children: a non-randomized controlled clinical trial].

OBJECTIVE: To investigate the clinical efficacy of glucocorticoid combined with ulinastatin in the treatment of Kawasaki disease (KD) in children. METHODS: A total of 104 children who were admitted and diagnosed with typical KD between January 2011 and December 2013 were assigned to ulinastatin group (methylprednisolone+ulinastatin; n=46) and intravenous immunoglobulin (IVIG) group (n=58) according to the severity of KD and the willingness of their parents. Observations for the two groups were performed to compare the changes in coronary artery diameter before and at 1 week, 3 months, and 6 months after treatment, fever clearance time, retreatment condition, changes in white blood cells (WBC), platelets (PLT), hemoglobin (HB), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) at 1 week and 3 weeks after treatment, and total in-hospital cost. RESYLTS: There was no significant difference in the coronary artery diameter between the two groups before or at 1 week, 3 months or 6 months after treatment (P>0.05). All the patients (100%) in the ulinastatin group vs 83% in the IVIG group had a normal body temperature after 48 hours of treatment (P<0.01). Two patients (4%) in the ulinastatin group and 10 patients (17%) in the IVIG group received retreatment. Significant differences were observed in ESR, WBC, and HB between them (P<0.01). The total in-hospital cost in the ulinastatin group was significantly lower than that in the IVIG group (P<0.01). CONCLUSIONS: For children with KD, methylprednisolone combined with ulinastatin does not increase the risk of coronary artery aneurysm, decreases in-hospital costs, is superior in controlling laboratory markers and shortening the duration of fever during the acute phase compared with the IVIG therapy.