The overall goal of the following experiment is to demonstrate a relatively simple and cost-effective method to provide a sustained drug delivery system to treat chronic conditions of the eye. This is achieved by first preparing the co-polymer resin pellets, creating a vehicle for the drug of choice. As a second step, the drug solution and D are combined to create the drug resin complex.
Next, the drug resin complex is inserted into the eye in order to ensure direct drug delivery to the retina. Results are obtained that show the successful delivery of the drug based on electro retinoscopy. So the implication of this technique is extending towards therapy of chronic retina conditions because it can offer slow release delivery to the target tissue directly.
So the main advantage of this technique over other existing methods, such as nanoparticles, hydrogels, and microfilms, is that it is relatively easy to follow and inexpensive, and therefore is achievable in a science laboratory environment. The first step is to prepare the copolymer resin pellets. To do this, place 20 LVA X 40 W pellets into a small glass beaker.
Fill the beaker with enough 100%ethanol to cover all the pellets. Cover the beaker with perfil and soak at room temperature for seven to 10 days. When ready, transfer the 20 washed pallets to a separate glass beaker in the fume hood.
Add four milliliters of di chloro methane cover and allow them to dissolve for approximately 45 minutes while the pellets are dissolving. Prepare a 40 microliter solution of your drug of choice at three times the concentration needed for a single dose. Next, prepare 40 microliters of fast green FCF.
Prepare a container of dry ice for flash, freezing the resin in a later step. When ready, load a pipette with 40 microliters of drug drug solution. Load a second pipette with 40 microliters of fast green solution.
Once loaded, add the two solutions simultaneously into the beaker. Mix rapidly using a glass stirring rod until the green dye is uniformly distributed Throughout the mixture, promptly transfer the beaker onto dry ice for 10 minutes to fast freeze the resin. Next, set up an evaporative chamber to evaporate the solvent, fill a larger container up to one third.
With calcium sulfate pebbles, create a well in the pebbles and carefully place the beaker in the well so that the pebbles reach up to half of the beaker. Cover the larger outside container with parfum and transfer the evaporative chamber to the freezer Store at negative 20 degrees Celsius for two to three weeks. To prepare the drug resin complex for implantation, remove the evaporative chamber from the freezer and transfer the solid drug resin block to a glass dish that is kept on ice.
With the eight of a microscope, cut a piece from the block that is approximately 0.05 millimeters in diameter and 0.1 millimeter in length using a TR refine or punch tool. Once all samples are obtained, wrap the remainder of the block in freeze proof material and keep at negative 20 degrees Celsius for later use. To begin confirm proper sedation in an anesthetized animal by toe pinch.
Next, transfer the animal to the surgery table. Disposable needles and sterile instruments are used throughout the surgery and should be prepared ahead of time. Apply drops to dilate the eye intended for surgery and administer a local anesthetic to keep the cornea moist.
Apply artificial tears throughout surgery after the pupil is fully dilated. Stabilize the eye using a pair of blunt curved forceps with the aid of an operating microscope. And a 25 gauge needle.
Make a full depth puncture wound to reach the vitreous approximately two millimeters from the limbus. Insert the prepared piece of the drug resin complex into the puncture wound using a pair of fine forceps after insertion. Apply antibiotic ointment to the eye as a prophylaxis for bacterial infection.
Observe the animal until fully recovered. Please note that analgesic may need to be used depending on the drug you deliver to the eye. This should be based on the adverse effects of the drug of choice, and if necessary, analgesia should be used according to the approved ethics protocol and by following the recommendation of the PI's veterinarian to assess the efficacy of drug delivery.
We used A PBA glutamate analog one day after implantation with the PB drug resin complex. There was no significant difference in the B wave amplitude between the eyes at all, flash intensities, except at 10 to the sixth fee where the implanted eye has a lower amplitude. However, one week after receiving the A PB drug resin complex, the amplitudes recorded from both eyes are significantly different with the implanted eye, showing no measurable amplitude at all.
Flash intensities therefore indicating that a PB has been delivered to the retina While attempting this procedure, it's important to remember that only glass equipment must be in contact with the solution after dark chloro methane has been added, and also all steps should be performed in a fume hood. After watching this video, you should have a good understanding of how to prepare and implant a drug raising complex to offer a direct delivery of the drug and slow release to the tissue.