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Team:Korea U Seoul/Project
From 2010.igem.org
Contents |
abstract
Toxic heavy metals such as arsenic, zinc, and cadmium in water are very harmful. Detecting these heavy metals is an important task. So we designed a heavy-metal-detecting E. coli. In order to design the system, we employed two fluorescence proteins (GFP, RFP) and aryl acylamidase as signal reporters. The aryl acylamidase converts a colorless acetaminophen(Tylenol TM) to a brown color substrate. Since the detecting E. coli has three heavy metal promoters, if more than two heavy metals coexist in a solution, the E. coli emit mixed fluorescence, so we simultaneously detect metals. Our goal is to synthetic modules put these three genes for different heavy metals in a row in E. coli and then utilized in the form of a lyophilized powder, which can be stored in a drug capsule to make it portable so that analysis of water is easily processed. We call it a "Capsule Cop".
Introduction
design
measurement
Result
Discussion
Freeze dry
The process of freeze-drying(lyophilization) involves the removal of water vapour by vacuum sublimation from the frozen state.
Freeze-drying has been widely used for many years as one of the preferred method for long-term preservation. Freeze-drying is particularly suitable for collections which supply cultures on demand because of its broad applicability, economy of storage space and ease of distribution. Freeze-drying is the most technologically complex of the preservation methods in use. It is labour intensive and requires the highest level of technical skill. The method is suitable for many types of microorganisms including most bacteria, yeast, sporing-fungi and some viruses, algae and protozoa.
One of the major advantages of freeze-drying is that the ampoules are particularly suitable as a means of distributing cultures because the viability and intengrity of the ampoules the airmail services. A disadvantage of freeze-drying is the relativelt high capital cost of commercial equipment. However, the principle of freeze-drying is quite simple and for small scale operations a laboratory freeze-dryer can be manufactures readily by any competent workshop. All that is a vacuum pump, a moisture trap, an evacuation chamber and a drying manifold.
