The oldest needle we know of dates back around 60, years ago: a human-constructed, animal most likely bird bone needle found in South Africa. Other needles made of bone and ivory have been discovered in Slovenia, Liaoning, China, and Russia, dating back to between 45, and 30, years ago.
The first needle with an eyelet dates to around 25, years ago. Although these artifacts originated in varying climates and cultures, they point to a time when modern humans were evolving away from their evolutionary ancestors. Armenian copper needles, for example, which date to around 7, BCE, mark the development of metal harnessing, a major development in human technology.
Early sewing needles, on the other hand, were crucial in the survival of the human species, helping early humans construct more fitted clothing made of animal furs and skins to protect themselves from the elements during the most recent ice age. The use of needles in the arts, which evolved from the more practical need to sew, has a more contested beginning. The earliest known example of embroidery was found in Russia, dating to around 30, years ago.
At the base of the barrel away from the needle attachment, two arms flare out. These pieces allow the needle user to press on the plunger with the thumb while holding the tube in place with two fingers. The other end of the barrel is tapered. The plunger, which is responsible for creating the vacuum to draw up materials and then discharge them, is made of a long, straight piece with a handle at one end and a rubber plunger head on the other.
The rubber head fits snugly against the walls of the barrel, making an airtight seal. In addition to ensuring an accurate amount of material is drawn in, the squeegee action of the plunger head keeps materials off the inner walls of the tube. The needle is the part of the device that actually pierces the layers of the skin. Depending on how deep the injection or fluid extraction will be, the needle orifice can be thinner or wider, and its length varies. It can also be permanently affixed to the body of the syringe or interchangeable.
For the latter type of system, a variety of needles would be available to use for different applications.
To prevent accidental needle stick injuries, a protective cap is placed over the top of the needle when it is not in use. Since hypodermic syringes come in direct contact with the interior of the body, government regulations require that they be made from biocompatible materials which are pharmacologically inert.
Additionally, they must be sterilizable and nontoxic. Many different types of materials are used to construct the wide variety of hypodermic needles available. The needles are generally made of a heat-treatable stainless steel or carbon steel.
To prevent corrosion, many are nickel plated. Depending on the style of device used, the main body of the tube can be made of plastic, glass, or both. Plastics are also used to make the plunger handle and flexible synthetic rubber for the plunger head. There are many manufacturers of hypodermic needles, and while each one uses a slightly different process for production, the basic steps remain the same, including needle formation, plastic component molding, piece assembly, packaging, labeling, and shipping.
The quality of the components of these devices are checked during each phase of manufacture. Since thousands of parts are made daily, complete inspection is impossible. Consequently, line inspectors randomly check components at fixed time intervals to ensure they meet size, shape, and consistency specifications. These random samples give a good indication of the quality of the hypodermic syringe produced.
Visual inspection is the primary test method. However, more rigorous measurements are also performed. Measuring equipment is used to check the length, width, and thickness of the component pieces. Typically, devices such as a vernier caliper, a micrometer, or a microscope are used. Each of these differ in accuracy and application. In addition to specific tests, line inspectors are stationed at various points of the production process and visually inspect the components as they are made.
They check for things such as deformed needles or tubes, pieces that fit together incorrectly, or inappropriate packaging. They have compiled a list of specifications to which every manufacturer must comply.
They perform inspections of each of these companies to ensure that they are following good manufacturing practices, handling complaints appropriately, and keeping adequate records related to design and production.
Additionally, individual manufacturers have their own product requirements. Since Alexander Wood introduced the first device, hypodermic syringe technology has greatly improved. Future research will focus on designing better devices that will be safer, more durable, more reliable, and less expensive to produce.
Also, improvements in device manufacture will also continue. One example of this is the trend toward utilizing materials such as metals and plastics that have undergone a minimum of processing from their normal state.
This should minimize waste, increase production speed, and reduce costs. Chicka, C. Diabetic's Jet Ejectors. Diabetic Gun for Personal Insulin Injection. Parker, Trissel, Lawrence. American Society of Health-System Pharmacists, Toggle navigation.
Made How Volume 3 Syringe Syringe. Diagram of a hypodermic syringe. Retraction of the plunger creates the vacuum to draw up materials, which can then be discharged by pushing on the plunger. Its rubber head makes an airtight seal against the walls of the barrel. Other articles you might like:. Also read article about Syringe from Wikipedia. User Contributions: 1. Comment about this article, ask questions, or add new information about this topic: Name:. E-mail: Show my email publicly.
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