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Research paper : Development of massive synthesis method of organic nanotube toward practical use (M. Asakawa et al.)−173 Synthesiology - English edition Vol.1 No.3 (2009) disassembled when the amphiphilic molecules that comprised the organic nanotubes were included into the cavities of the cyclodextrin (Figure 8). We suspect that the range of applications of these organic nanotubes as functional materials will increase with the discovery of this simple decomposition method performed under mild conditions.4.4 Safety assessment of organic nanotubesThe safety assessment items for our organic nanotubes were discussed and decided in conference at AIST with departments related to technology transfer, such as the Collaboration Promotion Department, Intellectual Property Department, Technology Licensing Organization, and Technology Information Department.As result, we conducted four safety tests: (i) biodegradation tests using environmental microorganisms according to “Methods of Testing New Chemical Substances,” Chemical Substance Control Law (CSCL), which is required if materials are to be synthesized at scales greater than 1 ton; (ii) oral acute toxicity tests using rats to meet requirements for use in food and drugs; (iii) ecotoxicity tests to assess the impact on aquatic organisms that are most likely to be influenced by exposure to the substance in the environment; and (iv) reverse mutation tests to assess mutagenicityNote 1).In the biodegradation tests using environmental microorganisms, we found that our organic nanotubes had almost no effects on humans, animals, or plants because they were almost completely degraded by environmental microbes within 28 days of release into the environment. In the oral acute toxicity tests, we observed no fatalities in the 2 weeks following oral administration of 5000 mg/kg organic nanotubes to rats. The acute toxicity was extremely low, with a least lethal dose (LDLo) of 5000 mg/kg or higher for both male and female rats. In the ecotoxicity tests using algae, water flea (Daphnia magna), and orange rice fish (Oryzias latipes), we tested a 100 mg/L organic nanotube solution for its 72-hour growth inhibition, 48-hour acute mobility inhibition, and 96-hour acute toxicity; we observed no growth inhibition, no mobility inhibition, and no acute toxicity. The reverse mutation test for mutagenicity was negative.5 Discussion: Comparison of research results and scenarioBy conducting Type 1 Basic Research into the development of a molecular design and synthesis technology for amphiphilic molecules that self-assemble into organic nanotubes, we succeeded in designing and synthesizing low-cost amphiphilic molecules using naturally occurring, recyclable raw materials. Moreover, by integrating Type 1 Basic Research into the development of a self-assembly technology with this molecular design and synthesis technology, we achieved the mass synthesis of organic nanotubes (Type 2 Basic Research). With these results, we enabled R&D into the practical use of these organic nanotubes.To solve the issues relating to utilization development, we are in the process of providing samples to companies, organizing issues that became apparent through communications with companies, and working on R&D to solve problems. To overcome the unique issues that arise in each field of utilization development, we will continue to cooperate with related fields and companies and develop appropriate research systems.For safety assessment, we conducted four tests: biodegradation tests using environmental microorganisms, oral acute toxicity tests using rats, ecotoxicity tests to assess the impact on aquatic organisms, and reverse mutation tests to assess mutagenicity. Safety was confirmed in all tests. The results have been regarded highly by many people when we have provided samples to companies; in addition, consideration of safety concerns from an early stage has proven to be useful in lowering the entry barrier to industry. Also, safe use of amphiphilic molecules synthesized from naturally occurring raw materials, as we had hypothesized in the molecular design phase, was proven in this case.For technological transfer policy, it was difficult for us to set a timeline when creating the schedule and, at present, it remains difficult to provide an optimal solution because so-called people, thing, and money factors are involved, and there are complex time factors that depend on utilization development. In this research subject, as a result of seeking potential applications of our organic nanotubes by transferring the material widely, it became clear that some fields were capable of implementing utilization quickly while others needed considerably more time. Our priority in advancing technological transfer was to optimize supply with demand by extracting R&D elements for fields that could implement utilization most quickly. Moreover, for rapid technological transfer, we decided to establish a joint research system based on a material transfer agreement, developed a system for open-type joint research, and began our own R&D examinations.(19)−Fig. 8 Decomposition of organic nanotubes through the addition of cyclodextrin.OH6-8OHOHOOOHOHOO〔〕CyclodextrinWater

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