Fluorescent sensing platform based on polyethyleneimine-protected copper nanoclusters for detection of chromium(VI) in real samples.

A new type of polyethyleneimine-protected copper nanoclusters (PEI-CuNCs) is favorably developed by a one-pot method under mild conditions. The obtained PEI-CuNCs is characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, Fourier-transform infrared (FTIR) spectroscopy and other techniques. It is worth noting that the proposed PEI-CuNCs demonstrate a selective response to chromium(VI) over other competitive species. Fluorescence quenching of PEI-CuNCs is determined to be chromium(VI) concentrations dependence with a low limit of detection of 8.9 nM. What is more, the as-developed PEI-CuNCs is further employed in building a detection platform for portable recognition of chromium(VI) in real samples with good accuracy. These findings may offer a distinctive strategy for the development of methods for analyzing and monitoring chromium(VI) and expand their application in real sample monitoring.

Single nucleotide polymorphisms of the maternal Msx2 gene and their association with fetal neural tube defects in Han ethnic group in Shanxi Province, China.

BACKGROUND: Neural tube defects are the most common human birth defects. The causes are multifactorial with complex genetic and environmental factors, although the exact genetic causes are unknown. This research was conducted to study the frequency of Msx2 gene polymorphisms in 59 women with a history of pregnancy with a neural tube defect and in 73 healthy controls. We aimed to determine the effect of this genetic polymorphism on the incidence of neural tube defects in the Han Chinese population. METHODS: We studied 59 mothers with at least one previous child with a neural tube defect (the case group) and 73 case-control subjects during the same period, from Shanxi Province, China. We analyzed the genotypic distributions and allele frequencies of Msx2 C386T polymorphisms in DNA samples from the case and control groups. A three-dimensional protein model was predicted using Swiss-Pdb Viewer software version 4.0. Disease association was analyzed using chi-square tests. RESULTS: Significant differences were observed in the genotypes and allele frequencies of the Msx2 C386T allele between the case and control groups (CT: 32% vs. 15%, P = 0.0073 and TT 15% vs. 4%, P = 0.013, respectively). Logistic regression analysis showed that the C386T mutation is a potential risk factor for neural tube defects (P < 0.05; OR: 3.466; 95%CI: 1.831 - 6.560). Three-dimensional structure prediction revealed that the Msx2 C386T mutation results in a threonine substitution for methionine at position 129 of exon 2, which might lead to structural mutations or dysfunctions in the protein encoded by Msx2. CONCLUSION: Maternal Msx2 C386T gene polymorphisms were associated with fetal neural tube defects in Han Chinese women in Shanxi Province.