Non-destructive measurement technique for water content in organic solvents based on a thermal approach

The water content of organic solvents is one of the crucial properties that affect the quality of the products and the efficiency of the manufacturing processes. The established water determination methods such as Karl Fischer titration and gas chromatography require skilled operators, specific reagents, and prolonged measurement time. Thus, they are not suitable for both on-line and in-line applications. In this study, we aim to develop a real-time and low-cost device with reliable accuracy. The proposed device based on a newly developed thermal approach could non-destructively detect the water content in multiple organic solvents at low concentrations with high accuracy and without the use of any specific reagent. Experiments were performed for the determination of water content in organic solvents such as methanol, ethanol, and isopropanol. The results show that the proposed device is feasible for the water content determination in methanol, ethanol, and isopropanol at 0–1% w/w. A Bland–Altman plot to illustrate the differences in measurements between the proposed device and coulometric Karl Fischer titration shows that most of the measurements lie within the limits of agreement where 95% of the differences between the two methods are expected to fall in the range of −0.13% and 0.09%.

The proposed device could non-destructively detect the water content in organic solvents at low concentrations with high accuracy and without any specific reagent. It could determine the water content in methanol, ethanol, and isopropanol at 0–1% w/w.     

Cytotoxic Activity of Piper cubeba Extract in Breast Cancer Cell Lines

This study aimed to evaluate the cytotoxicity of a crude extract of Piper cubeba against normal and breast cancer cell lines. To prepare the extract, P. cubeba seeds were ground, soaked in methanol and dichloromethane and isolated by column chromatography. Fractions were tested for cytotoxicity effects on normal fibroblast (L929), normal breast (MCF-12A) and breast cancer cell lines (MCF-7, MDA-MB-468 and MDA-MB-231). The most effective fraction was selected for DNA fragmentation assay to detect apoptotic activity. The results showed that the methanolic crude extract had a higher cytotoxic activity against MDA-MB-468 and MCF-7 than a dichloromethane crude extract. Then, the methanolic crude extract was separated into six fractions, designated A to F. Fraction C was highly active against breast cancer cell lines with an IC₅₀ value less than 4 μg/mL. Therefore, Fraction C was further separated into seven fractions, CA to CG. The ¹H-NMR profile showed that Fraction CE was long chain hydrocarbons. Moreover, Fraction CE demonstrated the highest activity against MCF-7 cells with an IC₅₀ value of 2.69 ± 0.09 μg/mL and lower cytotoxicity against normal fibroblast L929 cells with an IC₅₀ value of 4.17 ± 0.77 μg/mL. Finally, DNA fragmentation with a ladder pattern characteristic of apoptosis was observed in MCF-7, MDA-MB-468, MDA-MB-231 and L929 cells, but not in MCF-12A cells.