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Dieckol is a brown algae-derived polyphenol that has broad bioactivity and low toxicity. Therefore, it is a promising lead compound for the development of therapeutic agents to treat various pathological conditions, including viral infections, allergies, diabetes, skin ageing, cancers, and neurodegenerative conditions. To exploit the pharmacological potential of dieckol, its stability, solubility, pharmacokinetics, and drug delivery must be improved. This can be achieved by the controlled modification of the hydroxyl groups, but the presence of eleven nearly equivalent hydroxyl groups makes the task highly challenging. In this study, the regioselectivities in five substitution reactions of the hydroxyl groups of dieckol under various SN2 reaction conditions were investigated. After reaction optimization, five substituents (methyl, benzyl, methoxymethyl, 3-hydroxypropyl, and 3-(ethoxycarbonyl)propyl) could be introduced at the 6-Oposition of dieckol with surprisingly high regioselectivity, as confirmed by 2D-NMR spectroscopic analyses. The prepared dieckol derivatives showed antioxidant and anticancer activities analogous to those of unmodified dieckol, indicating that the mono-O-substitutions did not affect the biochemical and biological characteristics of dieckol. Therefore, the proposed methodology for the mono-O-substitution of a specific oxygen of dieckol is a powerful tool to add various pharmaceutical attributes to dieckol, thus contributing to the development of various dieckol-based drug candidates.

In recent years, the challenge of efficient oil-water separation has become the subject of immense fundamental research, with significant impact in the development of industrial applications. This article reviews the recent progress in the fabrication of porous polydimethylsiloxane (PDMS) materials, which are the most widely investigated materials for oil-water separation. Various strategies for the fabrication of porous PDMS have produced a diversity of bulk and surface structures, where these structures in turn determine the performance of the materials for oil-water separation. Understanding the interrelationship governing the fabrication strategy, structure, and performance is essential for the development of future selective oil absorbents with improved commercial potential. The separation of organic contaminants from industrially produced wastewater is a serious environmental challenge, and the preparation of superior oil absorbents is critical for overcoming this challenge. To address the issues in the development of promising candidates as oil absorbents, the current strategies for the design of low-surface energy coatings of three-dimensionally (3-D) interconnected porous materials are also discussed. The reusability, surface roughness, and superhydrophobic properties are discussed as vital parameters.

This paper uses pragmatic findings and lessons learned from three case studies to deduce that community-based rainwater harvesting (CB-RWH) is an innovative solution to develop sustainable drinking water supply systems in developing countries, especially in Africa and Asia. Taking advantage of traditional community-based activities in African and Asian villages, the water supply system can be significantly improved with the introduction and implementation of CB-RWH systems. Furthermore, sustainable, safe water sources in Africa and Asia can be brought to fruition when transparent self-regulatory management systems are supported through comprehensive design and maintenance guidelines and funded from private and public sources. To this end, the potential for CB-RWH to lead toward greater resilience and sustainability was investigated. Based on case studies of three successful demonstration projects in Africa and Asia, this paper identifies 14 innovative solutions resolving technical, economic, and social problems which have been barriers preventing the wide implementation of CB-RWH in developing countries, especially in Africa and Asia. It also recommends strategies to promote CB-RWH in African and Asian villages, which include the following: implementation of more pilot projects at local levels; promotion of and education in rainwater preservation and harvesting at all levels of the education system; and innovation in micro-funding systems in cooperation with corporate social responsibility activities. These strategies will promote the implementation of CB-RWH as a mainstream and high-priority technique for national, regional, and global water strategies.

Catastrophes can occur without warning and inevitably cause short-term and long-term problems. In disaster zones, having an action plan to alleviate difficulties can reduce or prevent many long-lasting complications. One of the most critical and urgent issues is sanitation. Water, energy, personnel, transportation, and the allocation of resources in disaster areas tend to become very limited during emergencies. Sanitation systems suffer in the process, potentially leading to crises due to unsafe and unhygienic surroundings. This article explores the problems of current sanitation practices in disaster areas and identifies the essential characteristics of sustainable sanitation systems. This study also presents a plan for an innovative and sustainable sanitation system using a waterless, portable, private toilet, in addition to a procedure for collecting and disposing waste. The system is agronomic, is socially acceptable, prevents contact with human waste, and can be used for individuals or families. Environmental pollution and social problems (such as sexual harassment) can be reduced both during and after restoration. (Disaster Med Public Health Preparedness. 2016;10:281–285)

The glucose level is a critical issue for individuals with diabetes, and thus selective and efficient detection of glucose is very important. A variety of optical techniques for the detection of glucose in solution have been reported. However, an effective, reversible, and reusable probe for glucose monitoring still remains a challenge. A new hydrogel sensor based on a copolymer was developed. The copolymer consisted of acrylamide and fluorescent monomers of fluorescein and rhodamine B, in which glucose oxidase (GOx) was immobilized on the resultant hydrogel and showed effective fluorescence-sensing performance toward glucose. GOx was immobilized on the hydrogel either by simple mixing or by covalent bonding to improve enzyme stability. The fluorophores of both fluorescein and rhodamine B moieties were pH-responsive and could change their fluorescence colors with pH changes. The change in the pH of the glucose solution was attributed to the hydrolytic decomposition of glucose, induced by the action of GOx. Upon exposure to glucose, the sensing hydrogel induced visual changes in fluorescence colors that could be identified by the naked-eye. The hydrogel sensor showed a highly reproducible response toward glucose and could be reused even after rinsing with buffer solution because of the robust covalent bond between the hydrogel and GOx. This work provides a facile and promising strategy for constructing a stable, naked-eye-detectable optical protocol that offers sensor reusability for glucose detection.

We present a new composite material composed of pH sensitive fluorescent dyes in a poly(N-isopropylacrylamide)-based hydrogel and incorporating glucose oxidase (GOx), which provides a platform for fluorescence sensing of glucose in the clinically relevant range of 100 μM to 100 mM in aqueous solution. Fluorescein and rhodamine B dyes are well known for their dramatic pH-responsive changes in fluorescence emission color, in which they were introduced to the hydrogel as comonomers. As D-glucose was oxidized to D-glucono-δ-lactone producing hydrogen peroxide and a proton through the enzymatic action of GOx, the generated proton affects the fluorescence of the composite hydrogel. The composite hydrogel exhibited high selectivity to glucose over other sugars and metal ions. The combined role of a soft hydrogel and oxidase highlights the potential of the new composite material design for selective detection of glucose in aqueous solution.

Large DNA molecules have been utilized as a model system to investigate polymer physics. However, DNA visualization via intercalating dyes has generated equivocal results due to dye-induced structural deformation, particularly unwanted unwinding of the double helix. Thus, the contour length increases and the persistence length changes so unpredictably that there has been a controversy. In this paper, we used TAMRA-polypyrrole to stain single DNA molecules. Since this staining did not change the contour length of B-form DNA, we utilized TAMRA-polypyrrole stained DNA as a tool to measure the persistence length by changing the ionic strength. Then, we investigated DNA stretching in nanochannels by varying the ionic strength from 0.06 mM to 47 mM to evaluate several polymer physics theories proposed by Odijk, de Gennes and recent papers to deal with these regimes.