In the extension part of rainbofilm, we delve into the various and precise regulation of stratification pattern. And this could be considered as the input of rainbofilm system.

As the output of rainbofilm system, we developed three different application: rainbofilm: sugarfilm, sensorfilm, and gluefilm. And we named Xfilm. X stands for all the coding sequences that can be differentially expressed in our stratified system. And each of these applications stands for one larger group of application: Synthesis, Sensing and, well, Others. Stratification as well as the unique properties of Biofilm play different yet crucial roles in these applications.

Sugarfilm is a biofuel producer, converting cellulose to butanol. Stratified expression of different enzymes increase efficiency by specifying reaction to one layer. It also reduces the burden of bacteria while increasing enzyme concentration. It forms spontaneously on the surface of cellulose. Then the product flow out of it.

Sensorfilm senses the concentration of Hg2+. Thanks to the intrinsic resistance to harmful environment of biofilm, the device is able to response to very high concentration of Hg2+. The stratification can also achieve a partial quantification of Hg2+.

Gluefilm uses oxygen level as a condition for adhesive expression. Glue is only expressed in anaerobic conditions. It can be used to attach two surfaces that fit each other with a tunable tolerance for mismatches. If accidentally touched by an object that does not fit, it will not be sticky because in aerobic environment adhesive protein is not expressed.