Frequently Asked Questions

The Matrix-Driven Delivery (MDD) System

Can the pellets be used in humans?
How does the MDD system work?
What are the pellets made of?
Can I get special shaped pellets?
Is the Matrix the same for all products?
Can you have more than one active product in the same pellet?
Are the pellets immunogenic?
Can I break a large pellet into smaller fragments?
How should the pellets be stored?
How long are the pellets good for?
How do I sterilize the pellets if I have doubt?

Implantation and Removal

How do I implant the pellets?
Should I sterilize the skin with alcohol before implantation?
Are the pellets sterile?
What is a trochar?
Must I sterilize the trochar after every implantation?
How do I sterilize a trochar?
Where should I implant the pellets?
Can the pellets be implanted other than subcutaneously?
Can I implant more than one pellet?
Are the pellets removable?
I have noticed after the experiment is over I can still see the pellet under the skin, do I need to remove it?

Animal Reactions to the Pellet

Why would I observe any edema or swelling around the pellet?

Release Rates and Dosages

When do the pellets start releasing the active product?
Is this zero order or first order kinetics?
How long will a pellet release a given product?
Are the release and blood levels always the same?
How do I check if the release is uniform?
How do I choose the proper dose for the pellet?
What are the smallest and largest dosages available?
What if I don't know exactly what dose to use?
Can I get a pellet that releases beyond 90 days?

Custom Pellets

What constitutes a custom pellet?
Does your time release technology work with other active products not listed on your website?
How do I order custom pellets?
Do I need to supply you with raw material for custom pellets?

The Matrix-Driven Delivery (MDD) System

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Can the pellets be used in humans?No, our pellets are for explicit use in laboratory animals only.
How does the MDD system work?The MDD Pellet System works by the double process of erosion of the pellet and diffusion of the active product.
What are the pellets made of?The pellet is made of a matrix fused with an active product. The ingredients are: cholesterol, cellulose, lactose, phosphates and stearates.
Can I get special shaped pellets?Yes, you can get any shape, in any form.
Is the Matrix the same for all products?No, we use more than 1,700 different types of matrixes.
Can you have more than one active product in the same pellet?Yes, pellets can be made with more than one active product depending on their chemical compatibility.
Are the pellets immunogenic?No, our pellets are biologically inert and do not affect the immune system.
Can I break a large pellet into smaller fragments?No, the pellets can not be broken because the active product is concentrated in the center of the pellet for steady release.
How should the pellets be stored?The pellets vary in storage requirements depending on the active product so be sure to check the bottle for temperature and light requirements and avoid humidity.
How long are the pellets good for?If the products are stored according to the instructions on the bottle they are guaranteed for 3 years from the date you received them.
How do I sterilize the pellets if I have doubt?We suggest two ways:
   1) Nitric Oxide gas sterilization
   2) UV light and blower in a laminar hood

Implantation and Removal

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How do I implant the pellet?For pellets up to 5mg we recommend using one of our precision trochars. Detailed instructions for implantation using the trochar or for pellets larger than 5mg can be found on our website, click here. Also, if you are implanting both placebo pellets and pellets containing the active product concurrently and you are using a trochar, implant the placebos first to avoid any residual active product contaminating the placebo pellets.
Should I sterilize the skin with alcohol before implantation?No, the pellets are designed to activate when they come in contact with fluids inside the body. Any exogenous fluids may alter the release rates of the pellets.
Are the pellets sterile?Yes, even if a pellet falls on the bench it is still sterile.
What is a trochar?It is a reusable, stainless steel needle with an obturator that can be used for easy pellet implantation. click here
Must I sterilize the trochar after every implantation?The trochar does not need to be sterilized after each implantation. If you do decide to sterilize the trochar with alcohol remember not to use it again until it is fully dry. Any exogenous fluids may alter the release rates of the pellets.
How do I sterilize a trochar?We recommend using an autoclave.
Where should I implant the pellets?Our pellets are mainly used subcutaneously between the skin and muscle tissue. The ideal implantation location for mice or rats is the lateral side of the neck between the ear and shoulder. However a location with the most space between the skin and muscle and the animal can not play with the pellet is sufficient.
Can the pellets be implanted other than subcutaneously?Yes, the pellets can be implanted intravenously, intramuscularly, intraperitoneally, in the eye, in the brain, in bone marrow, in the mammary gland, in the cervix or uterus.
Can I implant more than one pellet?Yes you can. Up to 20 pellets can be implanted depending on the physical size of the animal.
Are the pellets removable?Yes, however the pellet cannot be re-implanted after it has been removed.
I have noticed after the experiment is over I can still see the pellet under the skin, do I need to remove it?No, the remaining matrix has no immunogenic effects and will be absorbed by the animal.

Animal Reactions to the Pellet

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Why would I observe any edema or swelling around the pellet?Edema could only occur if the pellet is too large for the animal or the underlying muscle was injured during implantation. The pellets are sterile and will not cause infection.

Release Rates and Dosages

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When do the pellets start releasing the active product?The active product begins releasing immediately after implantation.
Is this zero order or first order kinetics?The pellets are zero order kinetics releasing a steady dose for the pellets designed release time.
How long will a pellet release a given product?The pellets release a constant, even amount of active product for the designed release time of the pellet.
Are the release and blood levels always the same?No, blood levels depend on the clearance of the active product by the host and the half life of the active product it self.
How do I check if the release is uniform?First remove the pellet. Then measure the amount of active product left in the pellet. By conclusion we can establish how much active product was released.
How do I choose the proper dose for the pellet?   1) If you know how much active product you want released daily use the following formula:
daily dose desired x number of days = dose for pellet
(example: 0.01mg x 21 days = 0.21mg pellet)

  2) If you want to know how much active product per day is release by a given pellet use the following formula:
dose of pellet / number of days = daily dose released
(example: 0.21mg pellet / 21 days = 0.01mg per day)
What are the smallest and largest dosages available?The smallest dose is 1µg and the highest dose is 200mg, but we can specially design a smaller or larger dose to fit your needs.
What if I don't know exactly what dose to use to get a desired blood level?We recommend doing a mini-dose response curve.
Can I get a pellet that releases beyond 90 days?Yes you can, but we recommend using multiple pellets instead. For example if you want 180-day release pellets use two 90-day release pellets instead. On day one implant the first pellet and on day 91 implant the second pellet.

Custom Pellets

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What constitutes a custom pellet?We consider custom pellets to be any active product we do not have listed in our catalog or online regardless of dose or release time.
Does your time release technology work with other active products not listed on your website?Yes, Our technical staff can apply our patented techniques to virtually any compound.
How do I order custom pellets?You can print out a copy of our custom pellet form and fax it to us or you can place an order for custom pellets online. Please be as thorough as possible when completing the forms.
Do I need to supply you with raw material for custom pellets?You can if you desire or if possible we can order it for you and charge you fair market price.