▎ 摘　　要

NOVELTY - Preparing composite bacteriostat, comprises (i) dissolving starch in water, adjusting pH of system to 5.3-6.1 to obtain a starch solution, adding sodium phytate to starch solution, and stirring for 2-5 hours to obtain starch-sodium phytate nanoparticles, (ii) uniformly mixing calcined diatomaceous earth, silane coupling agent and starch-sodium phytate nanoparticles in water and stirring at 60-80 degrees C for 0.5-3 hours to obtain modified starch-sodium phytate nanoparticles, (iii) ultrasonically dispersing graphene oxide in ethanol for 15-30 minutes to obtain a graphene suspension, adjusting pH of system to 7.6-8.5, then adding 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide, N-hydroxysuccinimide and amoxicillin, stirring and reacting for 24-48 hours to obtain graphene oxide modified amoxicillin and (iv) ultrasonically dispersing the modified starch-sodium phytate nanoparticles and graphene oxide modified amoxicillin in ethanol solution for 3-8 minutes and microwave reacting for 1-5 minutes. USE - The composite bacteriostat is useful in an automobile interior (claimed). ADVANTAGE - The composite bacteriostat has long-lasting bacteriostatic and antibacterial effects, can effectively inhibit the growth of indoor bacteria, has no toxic side effects on human body, and is environmentally friendly. DETAILED DESCRIPTION - Preparing composite bacteriostat, comprises (i) dissolving starch in water, then adjusting pH of the system to 5.3-6.1 to obtain a starch solution, adding sodium phytate to the starch solution, and stirring for 2-5 hours to obtain starch-sodium phytate nanoparticles, (ii) uniformly mixing calcined diatomaceous earth, silane coupling agent and the starch-sodium phytate nanoparticles in water and stirring at 60-80 degrees C for 0.5-3 hours to obtain modified starch-sodium phytate nanoparticles, (iii) ultrasonically dispersing graphene oxide in ethanol for 15-30 minutes to obtain a graphene suspension, adjusting the pH of the system to 7.6-8.5, then adding 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide, N-hydroxysuccinimide and amoxicillin, stirring and reacting for 24-48 hours to obtain graphene oxide modified amoxicillin and (iv) ultrasonically dispersing the modified starch-sodium phytate nanoparticles and graphene oxide modified amoxicillin in ethanol solution for 3-8 minutes and microwave reacting for 1-5 minutes. An INDEPENDENT CLAIM is also included for composite bacteriostat prepared by the above mentioned method.