blunt or beveled tips. The blunt tip is used for injection into soft tissue and
when a uniform solution distribution is needed. The beveled style is used
for applications that involve the penetration of a tough tissue.
diffusion in the large tip ID. When the tip ID is equal or larger than 100
micron, the error caused by tip diffusion is in the nanoliter range level
((100 micron)^3 = 1 nanoliter). With a 36 gauge needle installed on the
NanoFil, the error caused by diffusion will be reduced to the sub nanoliter
level, making accurate injection of a nanoliter possible.
penetrates better than one with a 25 degree angle, however the distance
between the upper opening to the tip (see section "F" in Fig. 2) is longer.
As a result, it requires a deeper penetration of the tip to achieve the same
level of liquid delivery. Deeper penetration means more tissue damage.
WPI's unique 25 degree beveled tip solves this problem with two extra
beveled surfaces. The tip of a single surface beveled tip is actually a
blade instead of a point. It dulls very quickly. In contrast, the tri-surfaced
tip has a real point. It not only penetrates much better but is also much
more durable. Our tests show that our 33 gauge, 25 degree beveled tip
economical way to inject. Any of our tips can be inserted directly
into the NanoFil syringe. Even the SilFlex tubing can be inserted to
switch from hand injection to the other methods listed below. The
limitation of this method is the difficulty achieving sub microliter
resolution.
the user to achieve nanoliter resolution and reproducibility. For
neural system injection, mount the UMPII on a stereotaxic frame.
plastic holder that is connected to the NanoFil by a 35 cm length
of flexible tubing. The NanoFil is mounted on the UMP II pump.
This configuration allows the user to hold the animal in one hand
and insert the needle with the other. When the needle reaches
the desired location, activate the pump using the footswitch and
the pre-programmed injection volume will be delivered. This
configuration gives a nanoliter level of accuracy and reproducibility.
It is best suited for applications such as the RPE and IO injection.
syringe developed in response to customer
requests for improved microinjection in mice
and other small animals. It makes quantitative
nanoliter injection much easier and more
accurate than any other method currently in use.
contamination of the injected sample.Injection
is now simpler, and less messy, and there is
no possibility of oil contamination in critical
applications such as ophthalmology research
(see the Retinal Pigment Epithelial (RPE) and Intra
Ocular (IO) injection kits listed below).
it is very difficult to backfill the solution at a
reasonable speed. NanoFil solves this problem
by using a tip coupling mechanism that makes
it possible to change the syringe tip during the
experiment. Simply load the sample using a
larger tip, such as the 26 gauge needle provided
with the syringe, and then replace it with a micro
microliter syringe, a solid ring or bushing is
permanently bonded to the tubing. Replacing the
tip in middle of the experiment is not practical.
With the NanoFil, tips can be exchanged by a
simple twist of the brass lock, gently pulling out
the tip, and replacing with the desired new tip.
To secure the tip, NanoFil uses an olive shaped
silicon gasket that is similar to, but much sturdier
than, some of the microelectrode holders used
for electro physiology recording. The silicone
gasket makes it possible to hold not only metal
tips but also glass and quartz tubing. Many
types of tubing can be easily connected to the
syringe as long as the outer diameter (OD) is
(ID) of the inside barrel. Flexible quartz capillaries
used in Gas Chromotography (GC) and Capillary
Electrophoresis (CE) can also be easily coupled to
the syringe.
beveled styles. Our studies have shown that
these tips will cause less trauma to the tissue
than any other form of micro syringe currently in
use. NanoFil has a unique coupling mechanism
that allows many different forms of small tubing
and tips to be coupled with the syringe barrel.
NF26BV-2