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Hiện nay, phương pháp von-ampe hòa tan anot xung vi phân (DP-ASV) sử dụng điện cực biến tính được cho là có độ chọn lọc, độ nhạy cao và giá thành rẻ. Trong nghiên cứu này, điện cực glassy carbon được biến tính bằng graphene oxide dạng khử kết hợp với màng bismuth in situ (BiFE/ErGO-GCE) để xác định đồng thời Cd(II) và Pb(II) trong môi trường nước. Một số thông số đã được nghiên cứu: lượng vật liệu graphene oxide, nồng độ của Bi(III) và thông số của phương pháp DP-ASV. Giới hạn phát hiện của Cd(II) và Pb(II) được xác định là 1,50 ppb và 1,39 ppb. Thêm vào đó, điện cực biến tính BiFE/ErGO-GCE cũng được áp dụng xác định đồng thời Cd(II) và Pb(II) trong hai mẫu nước sông Hương và An Cựu. Kết quả được so sánh với phương pháp khối phổ plasma cảm ứng cho kết quả có ý nghĩa.

Curculigo orchioides Gaertn. is used in traditional medicine in Vietnam. Its antioxidant potential was evaluated through DPPH radical scavenging and the total antioxidant capacity method. The data resulted from DPPH radical scavenging activity indicate that Curculigo orchioides display high activity with a low IC50 value (22.78μg/mL), approximately 1.5 times less than that of curcumin (34.34 μg/mL). The total antioxidant capacity of the extract is equivalent to 132.48 ± 1.48 mg GA/g or 264.45 ± 2.34 μmol AS/g. The composition of Curculigo orchioides, including the total phenolic, total flavonoid, polysaccharides, and triterpenoid saponins, was examined by using the colorimetric method with reagents, and their quantity is equivalent to 196.24 ± 1.45 mg GAE/g, 78.49 ± 1.78 mg QE/g, 4.34 ± 0.08 %, 47.60 ± 0.24 mg Rb1/g (Rb1: Gypenoside III), respectively. Specifically, the total triterpenoid saponins content of Curculigo orchioides has been reported for the first time.

The objective of this paper is to evaluate the effects of extraction temperatures on in vitro antioxidant potential of polysaccharides from the Ophiocordyceps sobolifera. The antioxidant capacity of Ophiocordyceps sobolifera polysaccharides was evaluated using 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) as a radical scavenger and the total antioxidant capacity methods. The results show that the highest antioxidant activity of the polysaccharides could be attained at the extraction temperature of 80°C. The total antioxidant capacity of olysaccharides from Ophiocordyceps sobolifera is from 0.1183 ± 0.0011 to 0.1454 ± 0.0021 mg GA/g or from 0.1105 ± 0.0004 to 0.1215 ± 0.0006 μmol AS/g. The polysaccharides have the most potent antioxidant activity with the lowest half‐maximal inhibitory concentration (IC50) value ranging from 0.97 mg/mL to 1.06 mg/mL.

High-performance liquid chromatography coupled with a photodiode array detector (HPLC- DAD) has been reported to quantify isolated compounds. This work was designed, therefore, to develop an HPLC-DAD system to determine luteolin in the extract solutions from Helicteres hirsuta. Luteolin was analyzed on an RP-C18 column using a mobile phase including acetonitrile – 0.1% phosphoric acid (v/v) = 1:1 (v/v) with a detecting wavelength of 347 nm, a flow rate of 0.5 mL/min, and a volume of an injected sample of 10 μL. The HPLC system was carried out at ambient temperature. The method shows linearity for luteolin in the range 0.02–1 mg/mL, and the recovery of luteolin is 94.07 ± 0.64 %. This is the first time, the contents of luteolin in methanol extracts from the plant parts of H. hirsuta (including branch, fruit, and aerial parts) were determined with a value of 49.06 ± 0.46, 56.61 ± 0.62 and 91.15 ± .42 µg/g, respectively.

We aim to estimate and compare the costs of operative and transcatheter closure for patients with secundum atrial septal defect (ASD) in Vietnam. This was a retrospective cross-sectional study based on medical records of congenital heart diseases (CHD) patients in Da Nang Hospital, Vietnam from 2010 through 2015. All costs in this study were calculated according to a provider's perspective. All pricing data were converted into USD at the 2015 exchange rate. A total of 258 patients with secundum ASD were recruited in the study, including 35 patients treated by operative closure and 223 patients treated by transcatheter closure. The total treatment costs of the transcatheter closure group (US $3,107.9) were higher than those of the operative closure group (US $2,080.5). The cost of the procedure and medical supplies accounted for 67.3% of the total treatment cost in the operative closure group, while the cost of occlusion devices accounted for 62.2% of the total cost in the transcatheter closure group. Given the advantages of the transcatheter closure procedure, reducing occlusion device costs may increase the proportion of patients treated with this technique.