GB2258618A

GB2258618A - Fluid medicament applicator

Info

Publication number: GB2258618A
Application number: GB9216661A
Authority: GB
Inventors: Bruce Gibbins; Anthony Robinson
Original assignee: Zenith Technology Corp Ltd
Current assignee: Zenith Technology Corp Ltd
Priority date: 1991-08-05
Filing date: 1992-08-05
Publication date: 1993-02-17
Anticipated expiration: 2012-08-05
Also published as: NZ239274A; IE922564A1; IE67002B1; GB2258618B; GB9216661D0

Abstract

The applicator, which may be for animal vaccine, has a body to be held between a user's fingers and thumb and a hollow interior in which is held a squeezable cartridge (3) holding sufficient fluid for repeated dosing. A conduit (5) leads from the hollow interior to a delivery end of the applicator and is of dimensions such that fluid is inhibited from gravity flow therefrom, means (7, 7a) being provided in a side wall of the body to enable expression of a drop or droplets of fluid from the conduit, and a scratcher (8) being provided for scratching the skin of the animal before or after applying a drop of the fluid. <IMAGE>

Description

A FLUID DROP APPLICATOR The invention comprises an applicator for administering droplets of a fluid medicament such as a fluid vaccine for example, particularly to animals.

Some medicaments such as vaccines must be delivered in fluid form percutaneously i.e. onto the cells of the cutaneous layer of the skin. In the case of fluid vaccines to vaccinate animals against disease or treat them for a pre-existing condition for example, this can be easily done by applying a drop of the vaccine fluid to the skin of the animal, and then scratching the skin through the drop of vaccine. An example of a disease against which animals are vaccinated in thi#s way is the sheep and goat disease variously referred to as scabby mouth, orf, sore mouth, contagious ecthyma, or contagious pustular dermatitis.

Animals are vaccinated as described, the vaccine comprising a carrier fluid comprising the live orf virus. It may similarly be necessary to apply other medicaments percutaneously, to animals or humans.

One known form of vaccine applicator for percutaneous application to animals is described in New Zealand patent specification 131723 and comprises a small container of a size to be hand held, with a stopper closing one end of the container, and two wire ends protruding through the stopper. In the patent specification it is described that vaccine is applied by inverting the tool onto the skin of the animal to be vaccinated and "drawing" a line with the scratcher. However, in practice the applicator must be shaken to deliver a drop of the vaccine on to the skin of the animal and the line then scratched through the drop. A disadvantage with this form of vaccine applicator is that, particularly because of the shaking often required in practice, little precision in the dosage delivered can be achieved.Also, the outlet orifice of the applicator tends to plug up with animal hair and oils from animal skin and the applicator leaks during transit when not in use.

Another technique . which is employed to percutaneously deliver a vaccine is simply a darning needle which has been cut through the eye of the needle and which in use is inverted with the two prongs of the open eye being used to scratch the skin of the animal. Before scratching, the cut-through eye end of the needle is dipped into a jar of the liquid vaccine and the vaccine is then scratched onto the animal's skin. A major disadvantage of this technique is the requirement to use two hands during vaccination and also the possibility of spillage of all the vaccine from the open container. ~ Also, again, the system cannot reliably deliver a measured dose of the vaccine.

The present invention provides a new or at least improved form of applicator which can repeatedly and reliably deliver a measured dose of fluid such as a vaccine, and in a one-handed operation.

In broad terms the invention may be said to comprise an applicator for a fluid medicament, comprising a body of a size to be hand held between a users fingers and thumb, having a hollow interior for holding a volume of fluid sufficient for repeated dosing, a conduit from the hollow interior to a delivery end of the applicator of dimensions such that fluid is inhibited from gravity flow from the delivery end of the conduit, means in a side wall of the body of the applicator enabling expressing of a drop or droplets of fluid from the delivery end of the conduit, and a scratcher for scratching the skin before or after applying a drop of the fluid.

Preferably the hollow interior of the applicator is adapted to receive and retain the fluid in a separate small fluid container or cartridge such as a vial or ampoule or the like, inserted into the hollow interior of the applicator. Such a container or cartridge may be a thin walled plastics container one end of which is sealed with a piercable plug, such than when the container is inserted into the applicator it will be pierced by the inner end of the conduit to 'connect the conduit to the supply of medicament in the container or cartridge. When emptied the medicament cartridge may be removed and disposed of and replaced with a fresh cartridge and the applicator itself may be reused.

Instead of the inner end of the conduit spiking into the medicament cartridge the cartridge may have a connection end having a small plastic valve system or a diaphragm arranged to be punctured on screwing of the fluid cartridge onto a threaded part fitting within the interior of the applicator, for example.

In another form of applicator of the invention instead of utilising separate disposable fluid containers or cartridges the applicator itself is disposable and comprises an integral volume or chamber for holding a supply of the fluid. The applicator is thrown away when the medicament has been used up and a new applicator filled with fluid used.

Preferred forms of applicator of the invention are ' further described with reference to the accompanying drawings by way of example and without intending to be limiting. In the drawings: Fig. 1 is a side view of the preferred form applicator without a medicament cartridge inserted; Fig. 2 is a cross-section view of the preferred form applicator without a cartridge inserted, along line I-I of Fig. 1; Fig. 3 is a side view of a preferred form of disposable cartridge for fluid medicament such as vaccine; Fig. 4 is a view of the disposable cartridge similar to Fig. 3 except that the cartridge has been rotated 90 degrees; Fig. 5 is a cross-sectional view of the cartridge along line Il-Il of Fig. 4; Fig. 6 is a cross-sectional view similar to Fig.

2 showing the cartridge inserted; Fig. 7 is a view similar to Fig. 1 but of an alternative form of applicator of the invention; and Figs 8 and 9 show in cross-section the delivery ends of further forms of applicator of the invention.

The preferred form application shown in Figs 1 to 6 comprises a tubular body 1 having a hollow interior 2 open at one end la (see Fig. 2), to receive a cartridge such as shown in Figs 3 to 5. The cartridge 3 is in use inserted into the hollow interior 2 of the applicator; Fig. 6 shows the preferred form applicator with cartridge inserted in cross-section. The applicator is of a size that it may be hand held by a user in a pen-like fashion.

The applicator has a delivery end 4. A conduit 5, in this form formed by a tube for example a fine bore stainless steel tube, extends through the delivery end 4 of the applicator to communicate with the interior of the fluid cartridge (see Fig. 2). At both ends the conduit 5 is open.

The dimensions of the conduit should be such that the fluid medicament is inhibited from flowing under gravity from the conduit, but can be expressed from the end of the conduit when using the applicator as will be described. The internal diameter of the conduit 5 may be of the order of 0.3mm, for example. Alternatively it is possible that the bore forming the conduit 5 may be formed directly into the applicator body, or by any other suitable arrangement.

The preferred form applicator shown is injection moulded from a plastics material such as polycarbonate which is preferred, but it is possible that the applicator could be formed from a lightweight metal such as aluminium for example. The applicator is generally tubular in shape, but it is also possible that the body of the applicator could be of other shapes such as hexagonal for example and in any other general form still providing the essential features as described herein.

A window 6 is formed in a side wall of the body of the applicator. In the preferred form applicator a resiliently flexible member 7 for example injection moulded with the body of the applicator, extends across the window 6.

The member 7 has a finger or thumb grip portion 7a. On the underside of the end of the member 7 is preferably provided a button pressure point 7b as shown. The member can flex in the direction of arrow A in Fig. 2, portion Ic of the body of the applicator acting as a hinge portion between the flexible member 7 and the major part of the body of the applicator.

The applicator also comprises a scratcher 8 with small prongs 8a extending from the delivery end of the applicator. In the applicator shown in the drawings the scratcher 8 is integrally moulded from the plastic material of the applicator body but alternatively the scratcher could be a fork shaped metal scratcher with small metal scratching prongs for example.

Figs 3 to 5 show the preferred form fluid medicament container or cartridge 3 in a side view. Fig. 4 shows the cartridge in side view but rotated around its long axis by 900. Fig. 5 shows the cartridge 3 in cross section.

The preferred form cartridge is of a thin-walled construction preferably formed from a suitable plastics material having a stopper 9 which is fitted into the open end to close the cartridge after filling with fluid vaccine or medicament.

In use, the cartridge 3 is inserted stopper end first into the hollow interior 2 of the applicator.

Referring to Fig. 6 the cartridge is pushed home so that the end of the conduit 5 which is preferably pointed as shown will pierce through the stopper 9 to communicate with the fluid medicament within. The stopper 9 is suitably formed from rubber or a suitable synthetic material that can be pierced and which will also seal around the conduit 5 to prevent leakage. Other than the stopper 9 the cartridge 3 should be made of a material such as thin walled plastic as referred to, that will return to its original shape after being depressed. While in the form of cartridge shown in Figs 3 to 5 the stopper and cartridge body are separate parts, they could be moulded as one. At the other end from the stopper 9 the cartridge 3 has a tab 10 to aid the removal of the cartridge from the applicator when empty, when another cartridge of vaccine may be inserted into the applicator.

The applicator may be used in a one handed operation to deliver a measured dose of fluid medicament. As stated the applicator is held by the user in a pen-like fashion. The member 7 can then be depressed by the users thumb or a finger to in turn apply pressure to the side of the cartridge 3 and by gentle squeezing push vaccine down the conduit 4. Further depression of the member 7 against the side of the cartridge will cause the droplet to fall away from the delivery end of the conduit 5, on to the skin of the animal. Finger pressure is then removed and the drop on the skin is scratched with the scratcher 8 to complete application of the vaccine or medicament.On releasing of pressure from the users thumb or finger, the member 7 will return to its normal position and the fluid cartridge side wall to its normal shape, in so doing drawing a small amount of air back into the fluid cartridge through the conduit 5 to equilibriate the pressure. The applicator may be used repeatedly, until the fluid in the cartridge is exhausted.

Typically the fluid container 7 may be of a size containing, for example, sufficient vaccine for 150-300 doses.

Fig. 7 shows another form of applicator of the invention. This form is similar to that of Figs 1 to 6 except that the means in the side wall of the applicator for expressing a drop or droplets of the medicament is slightly different. In this form the applicator has a window 11 in its side wall and no member equivalent to the member 7. In use a users finger or thumb can apply pressure directly to the side wall of the fluid cartridge in the applicator by pressing through the window 10.

Figs 8 and 9 show the delivery ends of alternative forms of applicator. In both of these forms the applicator has a drop-forming chamber 12 at the delivery end of the conduit 5. In the form of Fig. 8 the tube forming the conduit 5 is flared as shown, rather than being a simple open-ended tube. In the form of Fig. 9 the drop-forming chamber 12 is integrally formed in the body of the applicator by a small counter bore formed in the delivery end of the applicator of a suitable volume, as shown. Such drop forming chambers are useful where the applicator is to deliver larger drops of medicament while still having a conduit from the fluid supply sufficiently small to inhibit leakage from gravity flow of fluid from the applicator.

In the foregoing description the applicator has been described with reference to the vaccination of animals but it is possible that the applicator could also be used for applying medicaments or the like to humans and the words "fluid" and "animals" in this specification are to be understood accordingly.

The foregoing describes the invention including preferred forms thereof. Alterations and modifications as will be obvious to those skilled in the art are intended to be incorporated within the scope hereof as defined in the following claims.

Claims

CLAIMS:

1. An applicator for a fluid medicament, comprising a body of a size to be hand held a users fingers and thumb having a hollow interior for holding a volume of fluid sufficient for repeated dosing, a conduit from the hollow interior to a delivery end of the applicator of dimensions such that fluid is inhibited from gravity flow from the delivery end of the conduit, means in a side wall of the body of the applicator enabling expressing of a drop or droplets of fluid from the delivery end of the conduit, and a scratcher for scratching the skin before or after applying a drop of the fluid.

2. An applicator as claimed in claim 1, wherein the hollow interior of the applicator is accessible to receive and retain said volume of fluid in a container or cartridge inserted into said hollow interior.

3. An applicator as claimed in claim 2, wherein the hollow interior of the applicator is open at one end for inspection of a said container or cartridge of fluid medicament into the applicator.

4. An applicator as claimed in either one of claims 2 and 3, wherein the means in a side wall of the body of the applicator comprises a window in the side wall through which by a users finger or thumb the side of a said container or cartridge inserted in the hollow interior of the applicator may be depressed to express a drop or droplets of fluid from the delivery end of the conduit.

5. An applicator as claimed in claim 4, wherein a resiliently flexible member extends across the window in the side wall of the applicator, depressable by a users said finger or thumb against the side of a said container or cartridge in the applicator to express a drop or droplets of fluid from the applicator.

6. An applicator as claimed in any one of claims 2 to 5, wherein the other end of said conduit extends into the hollow interior of the body of the applicator, to puncture and enter through the wall of a said container or cartridge to communicate with the fluid medicament therein on insertion into the interior of the applicator.

7. An applicator as claimed in any one of the preceding claims, formed by injection moulding from a plastics material.

8. An applicator as claimed in any one of claims 2 to 7, together with a said container or cartridge for fluid medicament of a size for insertion into the hollow interior of the applicator.

9. An applicator for a fluid medicament substantially as illustrated in Figs 1 to 6, or as illustrated in Fig. 7, of the accompanying drawings and described with reference thereto.