Non-enzymatic electrochemical glucose sensor based on monodispersed stone-like PtNi alloy nanoparticles.

Monodisperse stone-like PtNi alloy nanoparticles (NPs) were synthesized at room temperature using an inverse microemulsion method. The results of XRD, HRTEM, and EDS demonstrate that these NPs consist of a disordered alloy that has (a) a face-centered cubic structure, (b) Pt/Ni atomic ratios of ∼5:1, and (c) a large number of atoms exposed on the NP surface and enclosed by low index facets. The material was placed on a glassy electrode which then displayed superior response to glucose. Best operated at a potential of 0.43 V (vs. SCE), the electrode has the following features: (a) a wide linear range (from 0.5 mM to 40 mM), (b) rapid response (<1 s), (c) a low detection limit (0.35 µM) and (d) a sensitivity of 40.17 µA mM-1cm-2). The NP sensor also is fairly selective over ascorbic acid, uric acid and fructose. The sensor has repeatability and durability for up to 30 days after manufacture. Graphical abstract Non-enzymatic glucose sensor based on a glassy carbon electrode modified with PtNi-NPS enclosed by low index facets. The sensor exhibits excellent features towards detecting glucose.

[Analysis of ß -thalassemia mutations in Guizhou Province].

OBJECTIVE: To investigate the spectrum of ß -thalassemia mutations in Guizhou Province. METHODS: For 542 individuals suspected to have ß -thalassemia by decreased mean corpuscular volume (MCV) and corpuscle hemoglobin (MCH) by routine blood test and hemoglobin electrophoresis, reverse dot blot hybridization (RDB) was performed to detect 17 known ß -thalassemia mutations, including 8 common and 9 rare mutations. For cases where no mutation was identified, the entire human ß -globin gene was screened to find other rare mutations. The distribution and frequencies of detected ß -thalassemia mutations were then analyzed. RESULTS: A total of 460 individuals were diagnosed as ß -thalassemia by DNA analysis, which included 352 heterozygotes, 67 compound heterozygotes and 41 mutant homozygotes. A total of 12 ß -thalassemia mutations were detected in these individuals. The mutations have ranked from high to low frequency as: CD17 (40.74%), CD41-42 (33.69%), IVS-II-654 (13.76%), -28 (3.70%), ß E (3.35%), CD71-72(1.94%), CD43 (1.06%), IVS-I-1 (0.71%), CD27-28 (0.35%), -29(0.35%), CAP (0.18%), and CD121 (0.18%). The former six mutations have accounted for 97.18% of all. CD121 (GAA> TAA) detected from a heterozygote, as a dominant mutation, has been firstly found in the Chinese population. CONCLUSION: The spectrum of ß -thalassemia in Guizhou Province showed certain distinct characteristics, with CD17 being the most common mutation. The newly discovered mutation of CD121 has expanded the spectrum of ß -thalassemia in Chinese population. Our result may provide valuable information for the prevention and control of ß -thalassemia in Guizhou.

Spectrum of ß-thalassemia mutations in Guizhou Province, PR China, including first observation of codon 121 (GAA>TAA) in Chinese population.

OBJECTIVES: Although the population prevalence and mutation spectrum of ß-thalassemia in most areas of south China have been characterized, the mutations have not been elucidated in Guizhou Province. The aim of this study was to investigate the spectrum of ß-thalassemia in this province. DESIGN AND METHODS: We detected and analyzed ß-globin gene mutations in 407 ß-thalassemia patients and carriers by PCR-based reverse dot blot (RBD) and direct sequencing methods. RESULTS: Twelve types of ß-globin gene mutations were detected. Among the 12 different mutations, six mutations are common, accounting for 97% of mutated alleles. The most prevalent mutation is codon 17 (A→T) with an allele frequency of 40.7%. In addition, codon 121 (GAA>TAA), a rare dominant mutation, was detected in a patient with ß-thalassemia intermedia for the first time in China. CONCLUSIONS: The results of this study will be useful in genetic counseling and prenatal diagnostic service of ß-thalassemia in Guizhou Province.