Multistage-batch bipolar membrane electrodialysis for base production from high-salinity wastewater

Bipolar membrane electrodialysis (BMED) is considered a state-of-the-art technology for the conversion of salts into acids and bases. However, the low concentration of base generated from a traditional BMED process may limit the viability of this technology for a large-scale application. Herein, we report an especially designed multistage-batch (two/three-stage-batch) BMED process to increase the base concentration by adjusting different volume ratios in the acid (V_acid), base (V_base), and salt compartments (V_salt). The findings indicated that performance of the two-stage-batch with a volume ratio of V_acid:V_base:V_salt = 1:1:5 was superior in comparison to the three-stage-batch with a volume ratio of V_acid:V_base:V_salt = 1:1:2. Besides, the base concentration could be further increased by exchanging the acid produced in the acid compartment with fresh water in the second stage-batch process. With the two-stage-batch BMED, the maximum concentration of the base can be obtained up to 3.40 mol∙L^–1, which was higher than the most reported base production by BMED. The low energy consumption and high current efficiency further authenticate that the designed process is reliable, cost-effective, and more productive to convert saline water into valuable industrial commodities.     

Mechanically Robust Shape-Memory Organohydrogels Based on Silk Fibroin with Organogel Microinclusions of Various Sizes

Organohydrogels (OHGs) are soft materials with antagonistic hydrophilic and hydrophobic domains that have great interest for many different applications. This study presents the preparation of mechanically strong OHGs with shape-memory function by incorporating semicrystalline organo-microgels within the pores of silk fibroin (SF) scaffolds. In the first step, SF cryogels with various pore diameters between 26 ± 8 and 17 ± 4 µm are synthesized by cryogelation of aqueous SF solutions at concentrations between 5 and 20 w/v%. In the second step, the pores of SF scaffolds are filled with an organogel precursor solution containing n-octadecyl acrylate (C18A), acrylic acid, N,N'-methylene(bis)acrylamide, and an initiator. Once the free-radical polymerization took place inside the pores, OHGs containing organo-microgels of various sizes are obtained. The incorporation of the organogel component in the cryogels generates crystalline areas due to the side-by-side packed C18 side chains. OHGs' melting temperature and crystallinity level can be varied from 42 to 54 °C and from 2 to 16%, respectively. The stiffness of OHGs increases from 5.9 ± 0.5 to 18 ± 1 MPa with increasing SF concentration from 5 to 20 w/v%, which is attributed to the decreasing pore size of the cryogels and increasing thickness of the pore walls.     

Metal Complexes for Cancer Sonodynamic Therapy

Sonodynamic therapy (SDT) for cancer treatment is gaining attention owing to its non-invasive property and ultrasound‘s (US) deep tissue penetration ability. In SDT, US activates the sonosensitizer at the target deep-seated tumors to generate reactive oxygen species (ROS), which ultimately damage tumors. However, drawbacks such as insufficient ROS production, aggregation of sonosensitizer, off-target side effects, etc., of the current organic/nanomaterial-based sonosensitizers limit the effectiveness of cancer SDT. Very recently, metal complexes with tunable physiochemical properties (such as sonostability, HOMO to LUMO energy gap, ROS generation ability, aqueous solubility, emission, etc.) have been devised as effective sonosensitizers, which could overcome the limitations of organic/nanomaterial-based sonosensitizers. This concept introduces all the reported metal-based sonosensitizers and delineates the prospects of metal complexes in cancer sonodynamic therapy. This new concept of metal-based sonosensitizer can deliver next-generation cancer drugs.