Protection of Photosynthetic Algae against Ultraviolet Radiation by One-Step CeO₂ Shellization

Abstract

Photosynthetic microalgae play an important role in solar-to-chemical energy conversion on Earth, but the increasing solar ultraviolet (UV) radiation seriously reduces the biological photosynthesis. Here, we developed a one-step approach to construct cell-in-shell hybrid structure by using direct adsorption of CeO nanoparticles onto cells. The engineered CeO nanoshell can efficiently protect the enclosed Chlorella cell due to its excellent UV filter property, which can also eliminate UV-induced oxidative stress. The experiments demonstrate that the resulted algae-CeO composites can guarantee their biological photosynthetic process and efficiency even under UV. This study follows a feasible strategy to protect living organisms by using functional nanomaterials to improve their biological functions.

Highly transparent cerium doped glasses with full‐band UV‐shielding capacity

“…While for Ce 4+ , UV light will be absorbed efficiently by charge transfer transition of Ce 4+ with ligand anion (Ce 4+ ‐O 2− → Ce 4+(−) ‐O − ) . Besides, CeO 2 is a very promising UV‐absorbing material because of its wide band gap (3.37 eV), and it shows higher transparency in the visible light range compared to TiO 2 and ZnO . Although the absorption of Ce 4+ occured at a longer wavelength region than that of Ce 3+ in previous research, it is hard to distinguish the absorption of Ce 3+ and Ce 4+ in the UV region …”

“…22,[28][29][30] Besides, CeO 2 is a very promising UV-absorbing material because of its wide band gap (3.37 eV), and it shows higher transparency in the visible light range compared to TiO 2 and ZnO. 11,28,[31][32][33][34][35][36] Although the absorption of Ce 4+ occured at a longer wavelength region than that of Ce 3+ in previous research, it is hard to distinguish the absorption of Ce 3+ and Ce 4+ in the UV region. 29 What we are interested in is that the combined absorption band that originated from Ce 3+ and Ce 4+ makes it possible to extend the region of UV-blocking.…”

Organism–Materials Integration: A Promising Strategy for Biomedical Applications

“…For example, CeO 2 shells upon algae C. pyrenoidosa was fabricated by a one‐step self‐assembly method to protect it from increasing ultraviolet (UV) irradiations. [ 54 ] Under strong UV light, the photosynthesis of algae could be suppressed, and the concurrent of reactive oxygen species (ROS) may together be fatal to the organism. In such alga–CeO 2 hybrid, most UV light can be filtered by the CeO 2 shell, and a small amount of ROS was also eliminated through redox reaction with the shell, leading to the protection of organism from UV light damage.…”

Single‐Cell Nanometric Coating Towards Whole‐Cell‐Based Biodevices and Biosensors

“…In addition to CaP and silica, some other oxides can also act as the protective shell inspired by diatom via direct coating or bio‐interface induced mineralization, such as MnO 2 , CeO 2 , and TiO 2 . MnO 2 ‐nanoenzyme shells were fabricated on both yeast and E. coli surfaces, with a simple solution mixing method.…”