Journal: ACS Applied Nano Materials, 12 December 2019, 3, 2, 1263-1271
Authors: Abhishek Panchal, Naureen Rahman, Svetlana Konnova, Rawil Fakhrullin, Donghui Zhang, Diane Blake, Vijay John, Evgenii Ivanov, Yuri Lvov
The authors of the article created new spherical structures stabilized by the hydrophobic halloysite nanotubes. These spherical structures (d = 0.5 mm) after encapsulation of microorganisms become capsules for storage of bacterial cultures. Halloysite nanotubes represent a natural, biocompatible and widespread aluminosilicate material. Hydrophilic halloysite by means of silane crosslinking of long alkane groups on the outer surface of the mineral becomes hydrophobic (wetting angle > 90°). Spherical structures are formed due to the water-repellent properties of the modified nanotubes and their ability to form a stable interface between the internal liquid and air. Modified halloysite promotes the growth of individual bacteria within spherical structures, for example, Alcanivorax borkumensis. The biofilm formed by the bacteria A. borkumensis on the inner walls of the capsules strengthens the structure and reduces evaporation, while maintaining the viability of the bacteria for 4 days. The ratio of the halloysite of the outer shell and bacteria forms the stable structures necessary for the encapsulation and storage of bacteria at room temperature.