New insight in algal cell adhesion and cake layer evolution in algal-related membrane processes: Size-fractioned particles, initial foulant seeds and EDEM simulation

Applications of microalga-powered microrobots in targeted drug delivery

Over the past decade, researchers have proposed a new class of drug delivery systems, bio-hybrid micro-robots, designed with a variety of living cell-driven micro-robots that utilize the unique mobility of natural organisms (bacteria, cells, exosomes, etc.) to transport effective drugs. Microalgae are considered potential drug delivery carriers. Recent studies have shown that microalga-based drug delivery systems exhibit excellent biocompatibility. In addition, microalgae have a large surfactant area, phototaxis, oxygen production, and other characteristics, so they are used as a carrier for the treatment of bacterial infections, cancer, etc. This review summarizes the modification of microalgae including click chemistry and electrostatic adsorption, and can improve the drug loading efficiency through dehydration and hydration strategies. The prepared microalgal drug delivery system can be targeted to different organs by different dosing methods or using external forces. Finally, it summarizes its antibacterial (gastritis, periodontitis, skin wound inflammation, etc.) and antitumor applications.

Microalgae cell adhesions on hydrophobic membrane substrates using quartz crystal microbalance with dissipation

Microalgal cell adhesion and biofilm formation are affected by interactions between microalgae strains and membrane materials. Variations of surface properties of microalgae and membrane materials are expected to affect cell-membranes and cell-cell interactions and thus initial microalgal cell adhesion and biofilm formation rates. Hence, it should be possible to identify the dominant mechanisms controlling microalgal cell adhesion and biofilm formation. The effects of surface properties of three different microalgal strains and three different types of membrane materials on microalgal cell adhesion and biofilm formation were systematically investigated in real time by monitoring changes in the oscillation frequency and dissipation of the quartz crystal resonator (QCM-D). The results revealed that in general a higher surface free energy, more negative zeta potential, and higher surface roughness of membrane materials positively correlated with a larger quantity of microalgae cell deposition, while a more hydrophilic microalgae with a larger negative zeta potential preferred to attach to a more hydrophobic membrane material. The adhered microalgal layers exhibited viscoelastic properties. The relative importance of these mechanisms in controlling microalgae cell attachment and biofilm formation might vary, depending on the properties of specific microalgae species and hydrophobic membrane materials used.

Effect of a Permanganate-Bearing Reactive Oxidant on Flocs in Electrocoagulation: Transformations and Interfacial Interactions

The electrocoagulation/ultrafiltration (ECUF) process is expected to address the issues of current wastewater increments and complex water reuse. However, the underlying mechanism associated with flocs remains unclear in the ECUF system, especially in the upgraded permanganate-bearing ECUF (PECUF) system. Herein, flocs and their formation, response to organic matter (OM), and interfacial features in the PECUF process were systematically explored. Results demonstrated that permanganate contributed to the rapid start-up of the coagulation process by forming MnO₂ and blocking the ligand-metal charge transfer process between adsorbed Fe(II) and solid-phase Fe(III). The response of flocs to natural OM (NOM) exhibited obvious time- and particle size-dependent characteristics. Based on this, the optimal NOM adsorption window was found to be in the interval of 5-20 min, whereas the optimal NOM removal window was located at the 20-30 min interval. Furthermore, the extended Derjaguin-Landau-Verwey-Overbeek theory revealed the underlying principle of the PECUF module for optimizing UF performance. On the one hand, it reduced the inherent resistance of the cake layer by modifying the colloidal solution, which guaranteed a small drop (15%) in initial flux. On the other hand, it enhanced the repulsive force among suspended particles to achieve a long-term antifouling effect. This study may provide insights into the selection and performance control of on-demand assembly modules in decentralized water treatment systems.

Wastewater treatment with algal based membrane bioreactor for the future: Removing emerging containments

The difficulty of developing pollutants in aquatic ecosystems and their potential effects on animals and plants have been raised. Sewage effluent can seriously harm a river's plant and animal life by reducing the water's oxygen content. Due to their increasing use and poor elimination in traditional municipal wastewater treatment plants (WWTPs), pharmaceuticals are one of the developing pollutants that have the potential to penetrate aquatic ecosystems. Due to undigested pharmaceuticals and their metabolites, which constitute a significant class of potentially hazardous aquatic pollutants. Using an algae-based membrane bioreactor (AMBR), the primary objective of this research was to eliminate emerging contaminants (ECs) identified in municipal wastewater. The first part of this research covers the basics of growing algae, an explanation of how they work, and how they remove ECs. Second, it develops the membrane in the wastewater, explains its workings, and uses the membrane to remove ECs. Finally, an algae-based membrane bioreactor for removing ECs is examined. As a result, daily algal production using AMBR technology might range from 50 to 100 mg/Liter. These kinds of machines are capable of nitrogen and phosphorus removal efficiencies of 30-97% and 46-93%, respectively.