MICROFIL™ Non-metallic syringe needle for filling micropipettes
WPI's new MicroFil fills micropipettes easily
and reliably. Its long and fine tip allows you to start the filling very close to the pipette tip, eliminating both air bubble formation and clogging due to the wash down of
dust particles.

Patent #5,294,325

PRICE PER PACKAGE
MF34G-5
Microfil, 34 ga.,
67 mm long
1-5 Packages
$49
MF28G-5
Microfil, 28 ga.,
97 mm long
1-5 Packages
$49
MF28G67-5
Microfil, 28 ga.,
67 mm long
1-5 Packages
$49
The transparent amber MicroFil needle is constructed from a combination of plastic and fused silica - no metal components are used. The MicroFil needle can be stored for days with the filling solution inside without clogging. The MicroFil's tip elasticity is sturdy and very flexible though not unbreakable. Since it is more flexible than stainless steel needles, moderate bending will not block or damage the MicroFil needle. The combination of plastic and fused silica in the MicroFil tip is sturdier than plastic tips, allowing easy and repeated insertions into micropipettes. MicroFil's luer fitting allows easy coupling to syringes and syringe filters.

MicroFil 34 gauge

The tip of MF34G is 67 mm long, 0.164 mm OD, 0.1 mm ID (34 gauge, 2.6-in. long). The fine, long tip will fit into most micropipettes intended for use in intracellular and extracellular recording as well as microinjection applications.

MicroFil 28 gauge

The tip of MF28G is 97 mm long, 0.35 mm OD, 0.250 mm ID (28 gauge, 3.8-in. long). The new MF28G67 is 67 mm long (28 gauge, 2.6-in.). 28-gauge is sturdier than 34-gauge but still flexible enough to allow a 360° bend. The longer tip of the MF28G can be effectively used for filling fine and long tubes such as those employed in WPI's Kwik-Tip, or to reach and fill corners that are difficult to reach by other means.

All MicroFil tips are equipped with luer syringe fittings for quick and easy connection to your filling syringe.

Chemical Information

MicroFil is made of fused silica (quartz), polyimide, and polyolefin. These materials are highly resistant to most acids, bases and organic solvents. MicroFil can be chemically sterilized or autoclaved.

Other Applications

Deliver diagnostic and analytical reagent. Since MicroFil is chemically inert, it has been successfully used in delivering highly reactive diagnostic reagent. It can also be used to deliver strong acid and strong organic solvent. Since MicroFil is non-metallic, it is invisible in NMR spectroscopy and other imaging.

Perfusion experiments. MicroFil has been successfully used as a gravity perfusion tube. It has stable dimension and close tolerance. Bending or other mechanical strain will not significantly affect the flow rate. Wall thickness can be as thin as 35 µm because of the material's high tensile strength. The thinner wall allows maximum flow with minimum outer diameter of the tubing. Many tubes can be staged together for patch perfusion experiments. It is also "chemically clean" and will not absorb lipophilic substances.

Microinjection with multi-barrel pipettes: Since MicroFil is heat resistant and flexible, it can be easily bonded to a micropipette with hot melt glue. The luer fitting on the back of the MicroFil allows easy and strong coupling to the pressure source.

Making ion-selective electrodes: MicroFil can be used to make semi-rigid polymer-based ion-selective electrodes with an outer diameter of 0.4 to 0.7 mm. It has the advantages of flexibility, low resistance, and small size.

Collecting fluid from biological system: MicroFil's semi-flexibility and semi-transparency make it a useful tool for collecting fluid from hard-to-reach points of the biological subject.


Custom MicroFil
All MicroFil products, including custom orders, can be shipped immediately. Custom orders for special needs can be made using nine sizes of MicroFil tubing in lengths up to 50 cm - except for CMF90UxxL which has a maximum length of 10 cm because of its high resistance to flow. Quantity discounts available. Specify length when ordering by inserting the length (in centimeter increments) into the catalog number in place of the XX's
CMF20GxxL 700 µm ID, 850 µm OD, 20 Gauge (pkg of 4)
CMF22GxxL 530 µm ID, 700 µm OD, 22 Gauge (pkg of 4)
CMF23GxxL 530 µm ID, 665 µm OD, 23 Gauge (pkg of 4)
CMF26GxxL 320 µm ID, 430 µm OD, 26 Gauge (pkg of 4)
CMF28GxxL 250 µm ID, 350 µm OD, 28 Gauge (pkg of 4)
CMF31GxxL 100 µm ID, 238 µm OD, 31 Gauge (pkg of 4)
CMF34GxxL 100 µm ID, 164 µm OD, 34 Gauge (pkg of 4)
CMF35GxxL 75 µm ID, 144 µm OD, 35 Gauge (pkg of 4)
CMF90UxxL 20 µm ID, 90 µm OD, approx. 36 Gauge (pkg of 4)