Micro blood collector

The blood collector of the present invention is a one-piece molded container consisting of three basic components - a) a base, b) a top, and c) a cap, with connecting straps. The top of the device is lockable to the base by male and female interlocking snap-fit rings, to prevent the top of the collector from "popping" off the base when squeezing the collector to produce suction for the withdrawal of blood from an animal. The tethered cap produces a self-contained unit for transporting blood collected in the field to a laboratory for centrifuging and testing. After centrifuging, by removing the top from the base there is easy accessibility to the plasma or serum.

The present invention relates to the container art, and is concerned with 
the provision of an improved blood collector which in combination with a 
standard hypodermic needle constitutes a complete blood-drawing (or, 
"bleeding") device. 
Blood collectors comprising a container and a cooperating closure -- 
whether or not of the "captive" sort -- are broadly "old" in this art, 
having been described in a plurality of disclosures including U.S. Pat. 
No. 2,958,439, Yochem and U.S. Pat. No. 3,419,179, Deuschle et al, as 
illustrative examples. Such articles were not adapted for use in drawing a 
sample of fluid (e.g. blood) from an animal but rather were adapted merely 
to receive and store a sample after the latter had been drawn by a 
separate device. 
A blood collector which was adapted for use in drawing a sample and for 
receiving and storing such sample when drawn had been proposed in U.S. 
Pat. No. 3,288,318, Corbin et al. Such a collector was not of a unitary 
nature, being assembled from two or more separate elements or members. 
The collector of the invention is for a one-piece article consisting of 
three strap-connected basic components -- (a) an open-mouthed base or 
vial, (b) a top and (c) a cap -- the top being connected to the base by a 
first strap and the cap being connected to the top by a second strap. 
The top component is either tapered or formed in the shape of a funnel in 
order that one end thereof shall fit the open mouth of the base whilst the 
opposite end thereof shall fit the hub end of a standard hypodermic 
needle. 
The top component has a tight fit in the mouth of the base. Preferably, the 
top component may be "locked" in the mouth of the base by virtue of 
male-female interlocking snap-fit rings on their mating surfaces. 
The cap has a press fit over the funnel end of the top component. When in 
place it yields a self-contained unit for transporting a blood sample from 
a collection locus to a laboratory for centrifuging and testing. 
While the aforesaid unitary article may be formed of any one of a variety 
of resilient organic materials, e.g., plastics broadly that are inert to 
body fluids, it preferably is formed of high density polypropylene. This 
latter material is inert to body fluids; does not interfere with routine 
diagnostic tests; is substantially transparent; is unbreakable; can be 
sterilized by autoclaving; and a base or vial component made from this 
material has a flexion characteristic suitable for being squeezed to 
develop therein a subatmospheric pressure conductive to drawing a blood 
sample from the vein in an animal. By reason of the aforesaid locking of 
the top component to the base component when in use, "popping off" of the 
top from the base, when the device is squeezed to create suction in the 
act of drawing a sample, is prevented. The top component can, of course, 
be separated from the base, as when the sample has been centrifuged and 
the technician is given easy access to the plasma (or serum) overlying the 
deposited solids. 
The three-component unitary device is relatively inexpensive to produce and 
hence is disposable if so desired. It is useful in collecting, 
transporting and testing body fluids, including blood, from animals 
broadly (not excluding human beings). The device is designed to conduct 
the bleeding of say 3.0 to 3.5 ml of blood, which amount is sufficient to 
perform complement fixation tests and other veterinary diagnostic tests. 
The base component may be, and preferably is, slightly tapered in the 
direction of the lower end thereof so as to accommodate the device in the 
centrifuge.

In the several figures, the one-piece device consists of a base component 
1, a top component 2, a cap component 3 and connecting straps 4 and 5, 
respectively. When the device is in "open " state, strap 4 connects the 
uppermost part of base 1 to the upper part of top component 2, and strap 5 
connects the upper part of top component 2 to the base of the 
frustoconical cap 3, said straps constituting convenient tethers, as well 
as flexible hinges, between the basic components. The device just 
described is in itself, a container for blood or other fluid. It is 
formed, by conventional molding technique, from high-density 
polypropylene. When the so-described device is associated with a 
conventional hypodermic needle the resulting article is a collector or 
bleeding device, as well as container, for blood or the like. 
Base component 1 is enlarged, at its upper end, in the form of a sleeve 6 
having an inner diameter substantially the same as is the outside diameter 
of the remainder of the base. On its inner surface sleeve 6 has an annular 
groove 7. 
Top component 3 has the general form of a funnel, constituted by (1) a 
first cylindrical part 8 having an outer diameter similar to the inner 
diameter of sleeve 6 of base component 1, (2) an intermediate part 9 which 
tapers to (3) a spout-like part 10. The outer diameter of part 10 is such 
that said part has a tight fit in the hub of a standard hypodermic needle. 
An annular ridge 11 is disposed on the outer surface of cylindrical part 8 
which ridge is so dimensioned and so disposed as to mate with aforesaid 
groove 7 when top component 2 is inserted in the mouth of base component 
1. 
Cap component 3 has such an inner diameter as to provide a tight fit with 
spout part 10 of top 2. 
In FIG 6 there is shown a standard hypodermic needle consisting of a 
pointed hollow needle part 12 and a hub part 1 the inner diameter of which 
hub is dimensioned to yield a tight fit on the spout-like part 10 of top 
2. 
In using the above-described article the technician seats top part 2 
securely in the sleeve 6 of base part 1, and fixes a hypodermic needle 
onto spout 10 of top 2; the technician squeezes base part 1 to expel some 
of the air present therein while inserting the needle in a vein of an 
animal whose blood is to be tested, and draws a small (3.0-3.5 ml) sample 
of blood into base 1. Then, the needle is withdrawn from the animal's vein 
and is separated from top part 2 of the device of the present invention. 
Cap component 3 is then fixed over the end of spout part 10, securely 
sealing the interior of the device. 
The resulting sample-containing device usually is transported to a 
laboratory where it is set in a centrifuge and the contents subjected to 
centrifugal force adapted to separate the solids content of the sample to 
the bottom of base 1 with the liquid content of the sample (i.e., the 
plasma, or serum) overlying the solids. The technician removes top 2 from 
base component 1 and, by means of a pipette or equivalent tool, withdraws 
the supernatant liquid for whatever diagnostic test is desired. 
While the device may be sterilized for re-use, it is customary to discard 
the device after a single use.