[0009] An antibacterial agent palladium-doped nano titanium dioxide, characterized in that the palladium doping amount is 1 to 5 mol%, and the average particle size of the palladium-doped nano titanium dioxide particles is 6-12 nm; it is made of PdCl 2 The solution was added dropwise to the isopropanol solution of tetrabutyl titanate at 30°C.
[0010] Preferably, the doping amount of palladium is 3 mol%.
[0011] A preparation method of nano titanium dioxide doped with antibacterial agent palladium, which is characterized in that the steps are as follows:
[0012] (1) PdCl 2 Dissolve in double distilled water to obtain solution A;
[0013] (2) Add tetrabutyl titanate dropwise to isopropanol, stir at room temperature for 30 minutes, adjust the pH value to 3-4 with acid to obtain solution B;
[0014] (3) At 30° C., use a constant pressure funnel to drop the solution A prepared in step (1) into the solution B prepared in step (2), stir at room temperature, and then age to obtain a sol;
[0015] (4) Wash the sol prepared in step (3) with distilled water until AgNO 3 The solution does not detect chloride ions, and it dries to get a gel;
[0016] (5) After grinding the gel prepared in step (4), it is calcined to obtain palladium-doped nano titanium dioxide powder, which is the antibacterial agent palladium-doped nano titanium dioxide.
[0017] Preferably, the acid in the step (1) is concentrated nitric acid with a concentration of 6M.
[0018] Preferably, the stirring time in the step (3) is 2h, and the aging time is 2h.
[0019] Preferably, the drying conditions in the step (4) are 80° C. and drying for 24 hours.
[0020] Preferably, the calcination condition in the step (5) is calcination at 450° C. for 2 h.
[0021] Application of the antibacterial agent palladium-doped nano titanium dioxide in antibacterial and antibacterial aspects.
[0022] The application of the antibacterial agent palladium-doped nano titanium dioxide in the aseptic palladium catalytic reaction.
[0023] The antibacterial effect test of the prepared antibacterial agent palladium-doped nano titanium dioxide by microcalorimetry:
[0024] The basic principle of microcalorimetry:
[0025] Establish an exponential growth model based on the restrictive growth conditions of microbial culture and derive the Logistic equation:
[0026] P t =P m /(1+αe -μt )
[0027] Where μ is the growth rate constant, α is the integral constant, P m And P t They are the maximum output power of bacteria and the output power of bacteria at time t. P obtained from the experimental test curve of thermal power-time m And P t etc Numerical value, the value of the growth rate constant μ is obtained by linear regression analysis, and the relationship between the growth rate constant μ and the concentration of antibacterial agent C is established through computer simulation. When the growth rate constant μ=0, the minimum inhibitory concentration (MIC) value of the antibacterial agent is obtained. The smaller the value, the better the antibacterial effect.
[0028] The experimental procedure for determining the effect of palladium-doped nano-titanium dioxide on the growth and metabolism of E. coli by microcalorimetry is as follows:
[0029] (1) Before the experiment, sterilize the instruments used under UV light for 30 minutes.
[0030] (2) Measure an appropriate amount of Escherichia coli bacteria from the liquid culture medium and add it to a certain amount of salt water to form a solution with the required concentration for the experiment.
[0031] (3) Weigh an appropriate amount of palladium-doped nano-titanium dioxide powder, add 10 mL of DMF (dimethylformamide), and ultrasonically disperse for 10 min, for use.
[0032] (4) Pipette 8 mL of the bacterial solution in (2) above and place them in 8 ampoules. No palladium-doped nano-titanium dioxide solution was added to the first ampoule, and a certain concentration of palladium-doped nano-titanium dioxide solution was sequentially added to the other 7 ampoules, the volumes were 50, 100, 150, 200, 250, 300, 350uL. After sealing, put it into the thermal activity detector and start recording data. When the thermal power-time curve of bacterial metabolism returns to the baseline, the experiment is considered to be over.
[0033] The palladium-doped nano titanium dioxide prepared by the method of the present invention has the following advantages:
[0034] 1. The prepared palladium-doped nano titanium dioxide powder has high purity, which can reach 98.5 mol%.
[0035] 2. The solution prepared by adding tetrabutyl titanate to isopropanol solvent and PdCl 2 The solution is mixed to prepare palladium-doped nano titanium dioxide powder, the particle size is small and uniform, and the average particle size can reach 6-12nm.
[0036] 3. The prepared palladium-doped nano titanium dioxide antibacterial agent has stable performance and strong antibacterial properties.
[0037] 4. The process is simple, the equipment requirements are low, the raw materials are easily available, and mass production is possible.
[0038] 5. When the doping amount of palladium is 1 to 3 mol%, the prepared nano titanium dioxide is anatase type; when the doping amount of palladium is 4 to 5 mol%, the prepared nano titanium dioxide is a mixture of anatase type and rutile type .
[0039] 6. In addition to being used as an antibacterial agent, palladium-doped nano titanium dioxide also has catalytic properties and can be used as a catalyst for partial palladium catalytic reactions.