The overall goal of this procedure is to prepare nano fibers decorated with functional groups. First, synthesize a block copolymer of two methoxy styrene and ethylene oxide via onic polymerization, and characterize it by proton NMR spectroscopy. Next electro spin the functional polymer and single wall nano tube solution into a composite nanofiber.
Then determine the current voltage behavior of the nano fibers after they have been exposed to the protein IgE E.Ultimately combining the ANI and a living polymerization with electro spinning can produce nano fibers decorated with functional groups that are capable of binding to specific proteins. In this approach to fabricating bio functional nano fibers, ano living polymerization permits the facile synthesis of bio functional polymers with controlled molecular weights. Further electro spinning technique permits the preparation of nano fibers decorated with functional groups, which can specifically interact with proteins.
This method can provide valuable insight into medical diagnostics. It can also be applied to other systems such as the monitoring of any single molecule desired in the environment by incorporating functional nano fibers into clothing, automobiles, et cetera, Can I Poly requires extremely stringent conditions. This video should help you master the manipulations necessary for the synthesis of a polymer and subsequent processing into a nanofiber Using benzophenone as indicator dehydrate, 200 milliliters of tetra hydron over sodium metal under dry nitrogen gas.
Also dry 10 milliliters of two methoxy styrene over calcium hydride for 24 hours. For the polymerization reactor. For this reaction, prepare a cold temperature bath maintained at minus 78 degrees Celsius using a slurry of isopropanol and liquid nitrogen.
Assemble a 100 milliliter round bottom single neck flask with a standard taper outer joint. Two flow control adapters with stopcocks and one Teflon stirring rod throughout the reaction flow. Ultrahigh purity nitrogen, so the system is inert.
Add 25 microliters of THF into the polymerization reaction flask. Then add two milliliters of the initiator solution. Next, inject four milliliters of the first monomer and allow reaction to proceed for 40 minutes.
Now add one milliliter of the second monomer for polymerization at room temperature for two days, terminate the polymer with six molar hydrochloric acid and methanol. Then to purify the polymer precipitate into hexanes and dry in a vacuum oven, proceed to characterize the polymer using NMR. Place the coupling reagents into a three neck flask and dry on a vacuum line for four hours.
Then inject dry 10 milliliter di chloro methane into the flask under nitrogen. Allow mixture to stir the reaction for 12 hours. At room temperature.
Filter the reaction mixture to recover the polymer precipitate twice into hexanes and methanol, dry precipitated polymer, and a vacuum oven at 40 degrees Celsius. Finally, determine the polymer structure and functionality by FTIR and HNMR. Dissolve 20%of the functional polymer in chloro benzene.
Now prepare two solutions of polystyrene in chloro benzene. The higher molecular weight polystyrene is used to improve the polymer changing entanglement and to obtain the optimum viscosity required for electro spinning. Mix the polymer solutions to form one-to-one and one to two ratios of the polymers.
Then add 1%single walled carbon nanotubes to the mixture and stir overnight. Assemble the electro spinning apparatus with a Glassman high voltage source, a silicon wafer, a syringe or chemic syringe pump, and a lamp for visualizing the procedure. As it progresses, withdraw a small quantity of the polymer swc NT solution into a hypodermic syringe mount the hypodermic syringe.
Now attach the clip bearing the high voltage to be applied to the needle on the syringe. To begin electro spinning power on the high voltage source and adjust voltage meter to 10 kilovolts. Then begin to push the plunger of the syringe.
Depending on the nature of the polymers in the composite, higher voltages may be required, especially if nano fibers under a hundred nanometers are desired. Unmount the silicon wafer and dry completely in a desiccate overnight. To observe the overall perspective of the nano fibers, first, obtain an image with an optical microscope.
Then utilize a scanning electron microscope to observe finer detail such as morphology, diameter, and average pore size. Further imaging within atomic force microscope allows you to observe the 3D topography of the nano fibers. Place a small piece of silicon wafer on which there are nano fibers on a mat tech.
Well cover slip. Add 10 microliters of fluorescently labeled antibody and incubate for an hour wash three times with P-B-S-B-S-A solution by gently dispensing solution on the wall of the mat tech dish, swirling the dish gently by hand, and then removing the buffer with a pipette to observe binding with IgE. The fibers are visualized by confocal microscopy.
A typical probe station used to determine the initial current voltage characteristics of the nano fibers consists of ABOs and lo micro zoomo microscope, a vacuum chuck stage for micro positioners, a multimeter for voltage measurements, and a source meter for low current input into the fibers. First, connect two micro positioners to a very low current source mount the probe arms of the micro positioners over the fiber mat on opposite sides with the tips touching the fibers. Then connect another two micro positioners to a digital multimeter.
Mount the probe arms in between the other two and land the tips on the fiber mat. Ensure that the four tips are as coline as possible. Input varying amounts of current typically in the nano amps range.
Now, measure the voltage drop across the outer tips for every magnitude of current sourced. Proceed to create current voltage plots and determine the type of device characterized by the fiber mat. In this method, the functional polymer of DNP is prepared by onic living polymerization.
The D functional initiator utilized in the polymerization is prepared by electron transfer reaction. In the process, a two methoxy styrene monomer is added to the initiator, followed by the second monomer ethylene oxide. And finally, the living polymer is terminated by methanol.
The structure of the functional polymer is confirmed by FTIR and NMR spectroscopy. The FTIR shows the complete disappearance of the oh broad absorption indicating quantitative functionalization with the CDNP group. The integration of the peaks in the NMR spectrum determine that the polymers are quantitatively functionalized.
The polymers are then functionalized by DCC coupling to incorporate functional DNP moieties in this mat of conductive nano fibers, the specificity of binding of electros spun DNP polymers towards IgE antibody is demonstrated fluorescently. Typically a nanofiber image under an atomic force microscope can measure nanofiber dimensions. SEM images indicate the morphologies of these fibers are linear and beaded.
The overall goal is to prepare fibers that are mostly linear. A current voltage plot of mats of nano fibers displays omic behavior of a resistor when the antigen is bound to the nano fibers. A change in resistance suggests that the functional fibers have potential application as the active component in sensors for single molecule detection.
Working with solvents such as tetra hydro, furin, di chloro, methane, chloro, benzene, and dimethyl sulfoxide can be extremely hazardous, so take the appropriate precautions Once master third. This approach can be done in five days. This includes polymer synthesis and characterization and non fiber fabrication and characterization.
While attempting this procedure, it's important to remember that anon polymerization is sensitive to product impurities. I hope you enjoyed The video and good luck with the experiments.