Ultrasensitive detection of dopamine via electrochemical route on spindle-like alpha-Fe2O3 Mesocrystals/rGO modified GCE
MATERIALS RESEARCH BULLETIN
Authors: Liu, Jun; Sun, Lingling; Li, Guangli; Hu, Jue; He, Quanguo
In this study, spindle-like alpha-Fe2O3 mesocrystals/reduced-graphene-oxide composites modified glassy carbon electrode (alpha-Fe2O3/rGO/GCE) is developed for ultrasensitive electrochemical detection of DA. Morphologies and crystal structures of this composite are characterized by SEM, TEM, XRD, Raman spectrum, and XPS, respectively. The electrochemical behavior of DA on these electrodes are investigated by CV and EIS. The electrochemical conditions are optimized systematically. As results, the oxidation current of DA on alpha-Fe2O3/rGO/GCE is 38.13-fold increase than that on bare GCE. It is ascribed to the high catalytic activity of alpha-Fe2O3 mesocrystals and large electrochemical active area of rGO. Under the best voltammetric condition, wide linear detection range (from 1.0x10(-8) to 9.0x10(-4) mol/L) and low LOD of 3.26 nM (S/N=3) are obtained on the alpha-Fe2O3/rGO/GCE. Furthermore, this electrode is also used for DA detection in real human serums samples successfully. This alpha-Fe2O3/rGO/GCE provides a good example in design of other mesocrystals-based composite materials for electrochemical detection.
Randomised trial of block and replace vs dose titration thionamide in young people with thyrotoxicosis
EUROPEAN JOURNAL OF ENDOCRINOLOGY
Authors: Wood, Claire L.; Cole, Michael; Donaldson, Malcolm; Dunger, David B.; Wood, Ruth; Morrison, Niamh; Matthews, John N. S.; Pearce, Simon H. S.; Cheetham, Timothy D.
Objective: First-line treatment of thyrotoxicosis in young people is thionamide anti-thyroid drug (ATD) in a blocking dose with levothyroxine replacement (block and replace, BR) or in a smaller dose tailored to render the patient euthyroid (dose titration, DT). Our objective was to determine which regimen provides more stable biochemical control. Design: A multi-centre phase III, open-label randomised trial comparing BR with DT in patients aged 2-17 years with newly diagnosed thyrotoxicosis at 15 UK centres. Methods: Patients were randomised shortly after diagnosis and treated for 3 years. The primary outcome was the percentage of serum thyroid-stimulating hormone (TSH) levels in the reference range between 6 months and 3 years. Secondary outcomes included the proportion of Free thyroxine (FT4) levels in the reference range, adverse event frequency and 4 years outcome (remission/relapse). Results: Eighty-two patients were randomised, with details on clinical course in 81 (62 Female); 40 were allocated to BR (41 DT). Three withdrew with one ineligible. The mean percentage of serum TSH within reference range was 60.2% in BR and 63.8% in DT patients; adjusted difference 4.3%, 95% CI (-7.8 to 16.4); P = 0.48. Proportions for FT4 were 79.2% in BR and 85.7% in DT patients; adjusted difference 6.8%, (-0.2 to 15.6); P = 0.13. Three patients developed neutropenia - all on BR. 6 BR and 10 DT patients were in remission at 4y. Conclusion: This randomised trial has shown no evidence to suggest that BR, when managing the young patient with thyrotoxicosis, is associated with improved biochemical stability when compared to DT.