The present invention generally relates to a unique technique for maintaining sterility and integrity of a lancet tip. More specifically, but not exclusively, the present invention concerns a manufacturing technique for quickly and easily producing a plurality of protective caps. Moreover, a plurality of lancet tips with protective caps can be stored in a cartridge or cassette.
Body fluid sampling devices have been developed to draw body fluid, such as blood or interstitial fluid, from a person and analyze the drawn fluid for any number of characteristics, such as blood glucose levels for diabetics. To monitor a patient's condition, a medical practitioner or the individual first creates an incision in the skin by lancing the subject's skin with a lancet. To avoid infection of the incision site and/or contamination of the fluid collected, the lancet is sterilized and packaged in a sterile manner prior to use. One form of packaging the lancet in a sterile environment is to place an entire lancet between two walls of a layered material and heat seal a portion of the layered material around the entire lancet.
The inner layers of the walls are usually formed from a protective sterilized padding and the outer layers of the walls are usually formed of a foil material. Between the inner walls and the outer walls is an intermediate layer formed of adhesive. Heat and pressure of a heat-sealing die or other mechanism are applied to the layered material around the perimeter of the entire lancet to form a heat seal line. As the heat and pressure are applied to the layered material, the adhesive in the intermediate layer seeps through the inner and outer walls along the heat seal line to secure the walls together. To use the lancet, a user must peel apart the two walls along the heat seal line to expose the lancet. One issue often associated with such packaging is that the user must separate the walls while at the same time maintain the lancet in the sterile package until the lancet is ready to be used. Another difficulty that can be associated with such packaging is an excess amount of adhesive may seep through the inner and outer walls making it more difficult for a user to separate the walls.
Another form of packaging the lancet in a sterile environment involves covering the tip of the lancet with a protective cap. One form of applying a protective cap onto the tip of the lancet is by injection molding. A material, usually plastic, is heated until it can flow and then the material is injected into a mold that contains a lancet. The mold is shaped to form a protective cap to cover the lancet. The material usually remains in the mold until it has cooled and solidified. The protective cap and lancet are removed from the mold.
A potential drawback for either sealing an entire lancet between two walls of material or injection molding is a long cycle time in which to seal the lancet or form the cap. An example cycle time to seal an entire lancet between two walls of a material would include placing the entire lancet between two walls of a layered material and heat sealing a portion of the layered material around the entire lancet. An example cycle time for injection molding would include heating the material, injecting the heated material into a mold, cooling the material in the mold to form a protective cap, and removing the cap and lancet from the mold. Another potential difficulty with sealing an entire lancet between two walls of material or injection molding is that both forms tend to be more costly to manufacture to protect the sterility of the lancet when compared to other forms of maintaining the sterility of the lancet. Another obstacle often associated with a lancet is the safe disposal of the lancet upon use of the lancet. For example, the user or medical practitioner using the lancet would not want to accidentally prick another person or themselves with a contaminated lancet thereby potentially exposing this person or themselves to disease. Frequently, the two walls of the sealed packaged lancet are separated to expose the lancet however; the two walls usually cannot be resealed together by the medical practitioner or the patient for safe disposal of a used lancet. Similarly, the replacement of the injection molded cap onto the lancet tip may be difficult for persons with limited hand dexterity.
Maintaining the sterility of the lancet while at the same time providing for ease in removal of the protective cap can be difficult, especially when the test is self-administered. Usually, the subject is either elderly or otherwise has some infirmity that reduces their hand dexterity, which in turn makes removal of the cap difficult. One solution has been to weaken the connection between the cap and the lancet, but by weakening this connection, the protective caps are more prone to be dislodged during shipping.
Thus, there remains the need for further improvement in this field.