The overall goal of this procedure is to assemble various types of polymer encapsulated metal nanoparticles into long chains of homo and copolymers. This is accomplished by first synthesizing metal nanoparticles with different sizes and morphologies. The second step is to encapsulate the nanoparticles with polystyrene block polyacrylic acid or P-S-P-A-A polymers.
Next, the polymer encapsulated nanoparticles are assembled into chains by incubating them in the acidic condition. Alternatively, a hetero assembly can be obtained by assembling chains of different nanoparticles. Ultimately, transmission electron microscopy is used to monitor the morphologies of the nanoparticles, the encapsulation of the nanoparticles, and the assembled chains.
The main advantage of this technique over the existing method, which usually requires stip moments for linear assembly, is that in it allows not only the formation of homo nanoparticle chains, but also the hetero assembly of different nanoparticles. We have this idea when we first observe the transformation of poly mice cell from spherical to cylindrical upon acid treatment. Begin this procedure with the synthesis of metal nanoparticles, including gold nanoparticles and delirium nanowires as described in the text protocol.
To encapsulate the gold nanoparticles in P-S-P-A-A first, purify the gold nanoparticle solution by adding three milliliters of the as synthesized gold nanoparticle solution to two micro centrifuge tubes. Centrifuge the solution at 16, 000 times G for 15 minutes, and remove the supernatant. Dilute the concentrated solution with 160 microliters of deionized water.
Next, prepare the P-S-P-A-A stock solution by dissolving eight milligrams of P-S-P-A-A in one milliliter of DIMETHYLFORMAMIDE or DMF. Then prepare the P-S-P-A-A solution by mixing 740 microliters of DMF with 80 microliters of the stock solution. In a glass vial, add the gold nanoparticles to 820 microliters of the P-S-P-A-A solution.
The final mixture has a volume of one milliliter with a DMF to water ratio of 4.5 to one. Next, add 40 microliters of two milligrams per milliliter, PSH and ethanol to render the surface of the nanoparticles hydrophobic. Incubate the mixture at 110 degrees Celsius for two hours to allow polymer self-assembly before slowly cooling the solution to room temperature in the oil bath to encapsulate carbon nano tubes with P-S-P-A-A first mix, 730 microliters of DMF with 80 microliters of the P-S-P-A-A stock solution.
Next, weigh about 0.2 milligrams of single wall carbon nanotubes to obtain 0.05 milligrams of carbon nanotubes. Estimate a volume of about one quarter of the measured sample. Then disperse this into the P-S-P-A-A solution sonicate the mixture in an ice water bath until it becomes a transparent, dark solution.
Next, at 180 microliters of deionized water dropwise to the solution, the final mixture has a volume of 990 microliters with a DMF to water ratio of 4.5 to one sonicate the solution at about 50 degrees Celsius for two hours before slowly cooling the solution to room temperature. To prepare spherical mycells of P-S-P-A-A, add 80 microliters of the P-S-P-A-A stock solution to 740 microliters of DMF. Then add 180 microliters of water, giving the solution A DMF to water ratio of 4.5 to one.
Incubate the polymer solution at 110 degrees Celsius for two hours before slowly cooling it to room temperature. To perform homo polymerization. Synthesize single line chains from the gold nanoparticles in P-S-P-A-A through purification of the nanoparticles.
Dilute 800 microliters of the as synthesized gold nanoparticles in P-S-P-A-A with 11.2 milliliters of water. Divide the solution into individual micro centrifuge tubes and centrifuge them at 16, 000 times G for 30 minutes, remove and discard the supernatant and add 1.5 milliliters of sodium hydroxide to each tube. Then centrifuge the tubes again at 16, 000 times G for 30 minutes to remove the supernatant.
Next, disperse the combined and concentrated P-S-P-A-A encapsulated gold nanoparticles in one milliliter of DMF water at a ratio of six to one in a glass vial. Then add five microliters of one molar hydrochloric acid, or HCL incubate the mixture at 60 degrees Celsius for two hours to allow the aggregation, coalescence and morphological transformation of the core shell nanoparticles. At this point, the ENE size go nanoparticle chain solution contains a product, nanoparticle chains, small chain and clusters.
Large agglomerates go nanoparticle. In PSPA mono, empty my cells DMF, and excess acid. To purify the nanoparticle chains.
First, remove the empty P-S-P-A-A my cells d, m, F, and acid by diluting 800 microliters of the as synthesized solution with 11.2 milliliters of sodium hydroxide. Then divide the solution into individual micro centrifuge tubes and centrifuge them at 16, 000 times G for 30 minutes, add 1.5 milliliters of sodium hydroxide to dilute the concentrated solutions before centrifuging the tubes again. As before, repeat this step once more.
The resulting solution contains the product, nanoparticle chains, small chains and clusters, and gold nanoparticles and PSPA. A monomers that are separated by differential centrifugation to enrich the gold nanoparticle chains, centrifuge the tube at 300 times G for 25 minutes to isolate and remove the larger conglomerates. Collect the supernatant before centrifuging it at 2000 times G for 30 minutes.
Now remove the supernatant containing mostly monomers and small chains and clusters. Collect the bottom solution, dilu diluted in 1.5 milliliters of sodium hydroxide and centrifuge at 2000 times G for 20 minutes to remove excess monomers. Repeat the process once more to perform block co polymerization of delirium nanowires with gold nanoparticles.
First, purify the 16 nanometer gold nanoparticle in P-S-P-A-A and TELLIRIUM nanowire in P-S-P-A-A as before. Then disperse the concentrated TELLIRIUM NANOWIRE in P-S-P-A-A in one milliliter of a six to 1D MF water mixture. Add two microliters of one molar hydrochloric acid, or HCL incubate the mixture at 60 degrees Celsius for 20 minutes.
Then at the concentrated 16 nanometer gold nanoparticle and P-S-P-A-A and an additional three microliters of one molar. HCL incubate the mixture at 60 degrees Celsius for two hours before cooling the solution to room temperature. Shown here are TEM images of 16 nanometer gold nanoparticles and P-S-P-A-A monomers, as well as 32 nanometer gold nanoparticles and P-S-P-A-A monomers also shown are monomers of carbon nano tube in P-S-P-A-A and monomers of P-S-P-A-A, my cells, TEM, images of the homo polymers of gold nanoparticles are shown here.
Single line chains of 16 nanometer gold nanoparticles in P-S-P-A-A are shown as well as single line chains of 32 nanometer gold nanoparticles in P-S-P-A-A, these TEM images display copolymers of nanoparticles shown here are random chains of 16 nanometer gold nanoparticles in P-S-P-A-A and 32 nanometer gold nanoparticles. In P-S-P-A-A also shown are block chains of Tellirium NANOWIRE in P-S-P-A-A and 16 nanometer gold nanoparticles in P-S-P-A-A While attempting this procedure, it is important to remember using a precise volume as a poly behavior is very sensitive to a pH and solvent combination.
