Abstract: A medical device provided with a subsurface bacteriostatic/bactericidal stratum to a predetermined depth is disclosed. The bacteriostatic/bactericidal stratum is introduced into the medical device by ion implantation of sufficient concentration to impart thereto the desired bacteriostatic/bactericidal property. The acquired bacteriostatic/bactericidal property has a useful life coterminal with the device. The treated medical device remains biocompatible, is non-leaching and, depending on the specific device, also is thromboresistant.

Abstract: A dry break coupling for joining together opposing passageways includes a male member and a female member, each of which includes a resiliently deformable rubber flap with cross-hair slits positioned to engage each other as the male and female members are moved axially toward their coupled position. Each of the male and female members also is provided with a normally closed but resiliently openable rubber septum position on the opposite side of its rubber flap from the engagement end of the respective members. The male member is provided with a blunt cannula which is fixed and a moveable carrier supporting the rubber septum. The female member is provided with an axially moveable support for the rubber flap and a fixed support for the rubber septum.

Abstract: A stomach lavage apparatus for the introduction of a highly absorbent antidote solution, such as activated charcoal, into the gastric cavity for the purpose of absorbing or otherwise counteracting a digested poison present therein, is described. The lavage apparatus is a completely closed system so that the antidote solution is never exposed to the atmosphere and there is no risk of spilling the antidote solution. The present invention thus comprises a flexible container for the antidote solution, the container being connectable to a lavage conduit leading into the gastric cavity by threading the container into a fitting provided with an internal spike. This causes the spike to puncture a rupturable seal provided in an exit port of the container, and the container is then squeezed to express the antidote solution therefrom and into the lavage conduit for introduction into the gastric cavity.

Abstract: A container closure having syringe tip connector is provided which comprises a coupling for securing the closure to the container, a dispensing port for releasably connecting the tip of a syringe and a cap for sealing the dispensing port. The closure has dual child-resistant capability in a "push and turn" mechanism for securing the coupling to the container and a latching flap type lid on the cap. The closure is especially useful for aspirating medication into a syringe for oral administration to children, adults or animals.

Abstract: This invention provides medical devices commonly accessed by syringes, said devices being characterized by comprising a cleanable, leakless built-in friction-fitting inlet-outlet port, said port being in the shape of the frustum of a cone, said frustum having a base and a top, said base being broader than said top, said frustum comprising a generally annular centrally disposed passageway extending therethrough and connecting with and in operative communication with a generally tubular neck at said base.

Abstract: A walker cart for an ambulatory patient includes a telescoping rod with a holder at the top end of the rod for holding one or more intravenous solution bags to which the patient is connected, and frame members to which infusion pump elements may be connected for the patient. The cart includes caster wheels for maneuvering the cart and handle elements which may be grasped by the ambulatory patient in several different ways, according to the desiderata or capability of the ambulatory patient.

Abstract: An adaptor for coupling rapid exchange-type catheters to a catheter re-sterilizing system. Specifically, the adaptor fluidly couples the guidewire lumen of a rapid exchange-type catheter to a source of sterilant so that the sterilant may be positively directed to and through the guidewire lumen, thereby allowing the catheter to be properly "reprocessed" or sterilized for reuse.

Abstract: A device for use in securing a venting pin or infusion spike to a delivery container such as a vial or bottle particularly when instilling a medicinal fluid to a patient through an intravenous set, catheter or similar fluid delivery set.

Abstract: Surface metallized polymeric implants, such as cannula, needles, catheters, connectors and the like, a dry coating method therefor and apparatus to accomplish the same are disclosed. The metallization of the implants is intended to improve their biocompatibility and to reduce infusion-associated phlebitis and infection. The method essentially includes the dry coating of the outside surfaces of the polymeric implants with a metallic thin film. The apparatus to effect the dry coating method essentially includes a vacuum chamber, an evaporator and an ion source mounted in operative association within the chamber, and means for rotatably mounting a plurality of polymeric implants for exposure to the evaporator and the ion source.

Abstract: A blood aspiration assembly and method has proximal, intermediate and distal tubing, an adjustable volume reservoir and an aspirator receiver. The receiver has a housing with a rigid casing and a resilient plug, and a liquid flow chamber. The resilient plug has a slit or perforation to allow passage of a blunt needle therethrough. The plug can have two parts of different compliance, which aligned slits or perforations. The blunt needle tip can be rounded or flat, with a side opening for the needle bore. The contour of the needle tip and the design of the plug are correlated such that the working force required to penetrate the needle tip into the plug perforation is considerably less than the force required for said needle tip to penetrate normal intact human skin of the hands or arms.

Abstract: An epidural connector has a housing in two parts, one of which contains a resilient, compressible slug with an axial bore into which an epidural cannula is inserted. The slug has a hexagonal external shape with flats separated from one another by rounded corners. The inside of the first part of the housing is of circular shape so that gaps are formed between the slug and the inside of the housing. The second part of the housing is screwed into the rear of the first part and has a female bore for receiving a male coupling. The forward end of the second part of the housing engages the rear end of the slug so that the slug can be compressed about the cannula and deformed into the gaps to accommodate cannulae of different diameters.

Abstract: Universal connectors suitable for use during the operation of vacuum or aspiration systems are disclosed.

Abstract: A fluid administration set with an infusion pump tube having indentations near its ends within its inner cylindrical wall. The indentations are preferably V-shaped annular grooves. Each groove engages an annular barb on a hollow fitting. The hollow fittings have base members for engaging retaining walls in the pump set apart from one another at a precise predetermined distance. The outer circumference of the infusion pump tube is enlarged in the area of the indentation. Tabs are provided on the hollow fitting assembly for securing the administration set against the infusion pump. The set may include a pressure dome for occlusion sensing on one of the hollow fitting assemblies.

Abstract: A connector for connecting two catheters and permitting the catheters to rotate relatively, the connector having a collar, a hub and a rotator, the hub and the rotator having an O-Ring therebetween. The rotator overlays the hub and has an internal surface that has a shape that is contoured to the shape of the O-Ring to make a seal therebetween. The hub has a surface at an end thereof with a projection thereon that biases the O-Ring into a sealing contact with the internal contoured surface of the rotator. The collar prohibits the hub from withdrawing from its overlaid position within the rotator by overhanging a surface extending radially from the hub. The hub receives a catheter, at the end opposite its contact with the O-Ring, the catheter wedging within the hub. The rotator received a catheter by an end having a luer lock with a common longitudinal axis about which they are all preferably symmetrical. Each component, including the O-Ring is preferably concentrically aligned.

Abstract: A hollow spike has a pointed distal end, a proximal end, and a luer fitting positioned in the proximal end of the spike to engage a complementary fitting associated with another IV component, e.g., an IV line. A reflex valve is disposed in the luer fitting to permit fluid flow through the spike when a complementary fitting is connected to the luer fitting of the spike, and to prevent fluid flow through the spike when no fitting is engaged with the fitting of the spike.

Abstract: A system and method for connecting a first fluid carrying tube and a second fluid carrying tube or tube fitting includes a first tube having a lumen therethrough and an open end, and a second tube or tube fitting having a lumen therethrough and an open end. The first tube and second tube (or tube fitting) are connected by connecting means, including a bubble elimination chamber, in a first position, wherein the lumen of the tube, the lumen of the connecting means and the lumen of the tube fitting form a fluid-tight circuit and the bubble elimination chamber is open to the circuit, to permit elimination of any bubbles in the fluid circuit to the bubble elimination chamber. The first tube, connecting means and second tube (or tube fitting) then are connected in a second position, wherein a continuous, fluid-tight, bubble-free fluid circuit is formed, and the bubble elimination chamber is closed to the fluid circuit. The connecting means may include a soft connector alone or in combination with a connector tube.

Abstract: A securing collar is used in combination with two tubular flow connectors to prevent the inadvertent disconnection of I.V. tubing sets. The securing collar includes a housing supported by one of the connectors, a radial flange extending from the housing, a tubular collar having a outwardly splayed end, at least two notches that separates the splayed collar into at least two elongated segments, a transition portion on the exterior of the collar, and a sliding annular locking ring. The locking ring slides on the collar from the proximal end over the transition portion to the distal segments so that the annular locking ring forces the splayed and segmented distal portions radially inward to grip the second connector.

Abstract: A plug-type connection is used for connecting at least one sterile electrical, optical and/or fluid-carrying line to at least one non-sterile apparatus with one line-side and one equipment-side plug unit respectively. The equipment-side plug unit is surrounded by at least one sterile foil which is clamped tightly between respective corresponding sealing and clamping edges of the line-side and the equipment-side plug units which surround the line to be plugged in. The line-side and/or equipment-side plug unit has a cutting device to cut the foil in the area of the lines to be contacted.

Abstract: This invention relates to endoscopic surgical instruments. In particular, the present invention relates to an apparatus for sealing the opening of an endoscopic suction/irrigation valve assembly and probe through which auxiliary endoscopic surgical instruments are inserted. The apparatus provides at least one shaft sealing surface which slidably yet also frictionally grips the shaft of an instrument inserted therethrough to hold the instrument tool at a desired position relative to the tip of the suction/irrigation probe. The invention also provides a means for attaching the sealing member to the valve assembly and a flexible seal radially extending within the lumen of the flexible sealing member for receiving of the instrument therethrough. The flexible seal can be comprised of a plurality of valve leaflets, each of which is independently secured to the luminal surface of the body portion of the sealing member.

Abstract: A calibrated disconnect joint for use with indwelling urethral balloon catheters is included between main portions of a catheter-drainage tube (10) and a bag-drainage tube (16). The calibrated disconnect joint includes male and female portions (or tubularly-shaped wall members) (54, 60; 70, 72; 90, 92; 110, 112) with one of these being a ribbed portion and the other being a grooved portion. If a tension of between 1/2 pound and 4 pounds, preferably between 21/2 and 3 pounds, is applied to the calibrated disconnect joint, the ribbed and grooved portions separate from one another to allow the main portions of the catheter-drainage and bag-drainage tubes to separate. Valves (86, 88) which automatically close their respective lumens upon separation are included on each of the ribbed and grooved portions so that upon separation little or no fluid escapes and there is a barrier to bacteria invasion.

Abstract: A connector is provided for mounting on an anesthetic vaporizer to connect the inlet of the vaporizer with a discharge port of a container of liquid anesthetic. The connector includes a first coupling attachable to the vaporizer and defining a first passage communicating at one end with the vaporizer inlet. A second coupling is attachable to the container and defines a second passage communicating at one end with the container discharge port. A third passage defined by one of the couplings and communicates with one of the first and second passages. A combination valve and mounting structure is cooperatively defined by the couplings to accommodate pivoting of the second coupling to a closed position occluding the first and second passages, to a raised fill position establishing communication between the first and second passages, and to a lowered drain position in which the first and second passages communicate through the third passage.

Abstract: A fluid dispensing apparatus is provided which comprises a flexible, collapsible fluid container in fluid communication with an adjustable volume multi-dose dispensing means.

Abstract: Coupling for connecting an implantable port catheter to flexible catheter tubes of varying size and diameter. A rigid tapered tube extends from a port opening in the catheter system housing and the catheter tube slides onto the end of the rigid tube. A clamping sleeve having a bore larger than the outer diameter of the tube has a circular gripping shoulder which bites into the flexible tube as the tube and sleeve are pushed onto the tapered surface of the rigid tube extending from the port opening to clamp the flexible catheter tube firmly between the shoulder and the tapered surface. The distance between the gripping shoulder and the tapered tube is variable to accommodate the size of the flexible catheter tube.

Abstract: A locking connector assembly is provided for use with Y-sites and/or other infusion line fittings. The connector assembly includes a shrouded connector including a cannula. A retention clip having a pair of prongs is provided. When the shrouded connector is installed on a Y-site or other fitting, and the retention clip is in the locking configuration, the prongs of the retention clip extend through a pair of opposing through-slots in the shroud to cooperatively engage a surface irregularity on the Y-site or other fitting thereby preventing disengagement of the shrouded connector from the Y-site or other fitting.

Abstract: Apparatus for administering dialysis, including a separable tubing coupling (32). The tubing coupling (32) consists of a hollow cylindrical element (42, 44) insertable into the lumens of the distal and proximal regions of the fluid delivery tube (16), and has a scored circumference at which the coupling can be broken-off by application of an adequate bending force. The device allows rapid and reliable disconnecting of the patient from the dialysis apparatus, without the need for scissors or a knife to be employed.

Abstract: A method and apparatus for simultaneously sterilizing and lubricating a medical coupling site prior to insertion of a male luer into the site. A fiber pad is provided containing a liquid composition including a sterilizing agent and a lubricating agent. The sterilizing and lubricating agents are preferably isopropyl alcohol and silicone oil, respectively, such that application of the lubricating agent to the medical coupling site results in the alcohol evaporating to leave behind a coating of silicone oil. The silicone oil lubricates an area on the coupling site contacted by the end of a male luer.

Abstract: A solution administration apparatus for patient care, for use with an associated solution administration system, which apparatus includes a laser drilled orifice flow control device to provide a controlled, predetermined flow rate of solution to the patient. The apparatus includes a tubing set and a laser drilled orifice flow restrictor, formed in a body, and in fluid communication therewith, for use with an associated fluid supply container. The system provides a controlled, predetermined flow rate of solution to the patient which is independent of, and relatively constant over minor variations in solution supply pressure and viscosity.

Abstract: A medical connector and method of using the connector to connect separate sections of medical tubing, especially tubing which is to be implanted in the human body. The connector includes generally cylindrical first and second end portions, the diameter of which are smaller than an enlarged middle portion. The end portions are sized to fit within the lumens of the tubing sections. The connection is made by grasping the enlarged middle portion and slipping each end portion into a respective tubing section until the tubing sections abut tubing stop surfaces located at each end of the enlarged middle portion. The enlarged middle portion makes the connector easy to handle and the tubing stop sections provide for accurate alignment of the connector between the tubing sections.

Abstract: The present invention provides a medical coupling site which is adapted to be attached directly to a standard male luer lock fitting. The coupling site includes a valve element contained within a tubular retainer. The retainer is provided with outwardly extending lugs for engaging the threaded locking collar of a male luer lock whereby the male luer lock will be held in positive mechanical locking engagement with the coupling site. The valve element is provided with rib members extending inwardly from an inner wall of the valve element toward a slit formed in a diaphragm such that the rib members act to bias the slit to a closed position. In addition, the valve element is formed with biasing means for engaging an inner wall of the retainer whereby the slit is further biased to a closed position.

Abstract: A gastric adapter comprising a three-way stopcock. The stopcock includes connectors having tapered surfaces for sealing tightly with the ends of nasogastric, gastrostomy and feeding tubing and includes fluid passageways of sufficient diameter so as to be capable of conveying viscous fluids such as emulsion, suspensions and slurrys to provide effective operation and use in the particular environment of administering critical fluids and medications through nasogastric and gastrostomy tubing.

Abstract: A connector having an occluder which transposes between a first position and a second position is provided for maintaining a sterile environment during connection and disconnection of fluid communication between a container and a fluid line. The occluder is in the form of a spherical ball integrally formed with a length of tubing. The occluder has a diameter slightly larger than an end of the connector such that the occluder rolls into the end upon disconnecting from the system. An interface may be provided to receive a single connector or a pair of connectors to assist in fluid control between the container and the fluid line.

Abstract: A hermetically sealed package is provided for the administration of a solution or other liquid to a patient. The package includes a blow molded container, cap, and releasable cover. The cap accommodates piercing of the cap and container with a draining spike. The cap has one or more self-closing seals or liners and can be disposed on the container so as to permit penetration of the cap and container by a piercing spike without contacting the parting line of the molded container. The cap includes a special structure for guiding the spike at the initiation of the piercing process, and the cap has an improved structure for sealingly engaging the spike upon insertion. As the container is drained, one of the container walls collapses toward the other to facilitate the draining process and provide a convenient shape for subsequent handling and storage.

Abstract: A connector assembly includes first and second fittings and first and second membrane assemblies. Each fitting defines a respective aperture. Each membrane assembly has a layer sealing the aperture and a removable contamination containment layer overlying a respective sealing layer. The first and second fittings may be resiliently coupled in biased opposition to urge positive contact between the first and second removable contamination containment layers and/or the first and second sealing layers. In one application, a connector assembly according to the invention may define a fluid communication path for handling a fluid without allowing the level of contaminants in the fluid to increase. A connector assembly according to the invention may be used to handle a biological fluid while maintaining the fluid free of viable contaminating microorganisms or preserving its sterility, for example.

Abstract: A dual direction check valve which facilitates the connection of an IV fluid line to the proximal end of a hypodermic needle that is used to make a veni puncture so that a patient may be infused with fluid from an IV medication bag, or the like. What is more, the check valve is adapted to reliably block the backflow of blood through the needle during the interconnection and start-up of the IV system. A resilient valve core formed from an elastomeric material has a peripheral sealing surface extending therearound. The check valve is closed to fluid flow in both directions when the sealing surface of the valve core mates against a complementary peripheral sealing surface which surrounds the valve core. The check valve is opened to fluid flow in both directions when an axial pushing force (e.g. generated by a Luer lock fitting) is applied to the valve core, whereby the valve core is compressed and the sealing surface thereof is separated from its complementary sealing surface to establish a gap therebetween.

Abstract: A coupling system for transferring fluids from a medicament-containing cartridge to an injection site comprises a fluid flow channel, a blunt cannula defining the distal end of the fluid flow channel, a needle cannula defining the proximal end of the fluid flow channel, and means for fixedly connecting the needle cannula to the blunt cannula.

Abstract: A female luer connector comprises a tube having an open, outer end in a luer-tapered bore communicating with the outer end. The tube carries a side arm that from a positioned spaced longitudinally from the open, outer end, with the side arm extending both radially outwardly from the tube and in generally longitudinal relationship with the axis of the bore toward the open, outer end, to define a space between the tube and the side arm for receiving an outer, threaded sleeve of a male luer lock connector. A cap is connected to the side arm through a plastic hinge in a position permitting the cap to pivot between a closed position in which the cap closes the open, outer end, and an open position in which the cap is spaced from the open, outer end. The side arm defines an effectively rigid, fixed configuration to position the hinge and cap to naturally and spontaneously permit pivoting to the closed position to the open position, typically upon pressing with a single finger.

Abstract: A capping device for covering the access port of a conduit connector includes a first cap having a downwardly extending skirt and an access opening through which a bronchoscope, catheter or other small diameter medical device may be inserted. The skirt includes an inwardly extending rim around its internal surface which detachably snaps over a lip around the access port. The access opening is selectively sealable by a second cap that is tethered to the first cap by a flexible tether strap. The second cap also incudes a downwardly extending skirt including an inwardly extending rim around its internal surface which detachably snaps over a lip around the first cap. The capping device further includes a flexible anchor strap extending from the first cap which snaps onto a knob on the connector, thereby retaining the capping device on the connector when not in use.

Abstract: A hollow needle fixed in a chamber establishes a connection between an upstream coupling and a downstream coupling when it passes through a plug. The plug is made of a material such that it regains its closure properties when the needle is no longer passing through it, and it is pushed away from the needle by a spring to a closure position in which it fills the outlet opening of the downstream coupling. The connector is particularly suitable for use in medical applications.

Abstract: A manifold has a plurality of stopcocks wrapped in a flexible cellular material saturated with an antiseptic liquid and contained in a housing. Each control element of the stopcocks is removable and can be rotationally integrated with a head portion of a stopcock via a shaped male part. The shaped male part engages a female cavity of a matching shape through openings provided in the housing and in the cellular material opposite the stopcocks. Markings showing the position of the stopcocks are visible from the exterior of the housing when the element is withdrawn.

Abstract: Means and apparatus for aseptically transferring material between enclosures. Apparatus for transferring the material includes a fluid receiver assembly (12) comprising an adapter (24), and a fitting (93) mounted in the adapter (24). The fitting has a plurality of needle guide channels (86) leading from the outside of the fluid receiver assembly (12) toward the interior of the enclosure (10), and seal means (26) at the ends of the channels (86). Pierceable, self-closing seal means (26) is between ends of each of the channels (86) and the interior of the enclosure. Projected extensions of the channels pass through corresponding holes (40) in the adapter, so that needles (101) inserted into the channels (86) can penetrate the seal means (26) and enter the interior of the enclosure (10). A plurality of needles (101) in a novel needle bundle (95) may be used in making the transfer.

Abstract: In a plug-type connector having two plug parts for producing and interrupting a flow connection, in order to enable sealing of the flow branches of the respective parts when separated from one another when the flow connection is interrupted, each plug part is terminated with a perforable septum with a cannula held so as to be longitudinally displaceable in one septum. The cannula and the septa are fashioned with reference to one another such that the septum holding the cannula offers lower resistance to the cannula upon penetration than does the other septum. This results in the cannula first penetrating the septum that holds it when the plug parts are joined and subsequently penetrating the other septum. When releasing the plug parts from one another, the cannula is first withdrawn from the septum that holds it and is then withdrawn from the other septum.

Abstract: The method of mounting a disc-shaped septum within a connector includes a step of deforming a thin annular wall at the end of the connector into a curled over shape so as to secure the septum in place. Curling over of these wall occurs under heat energy which is applied only to the end of the connector without heating of the main body of the connector. Deformation of the thin end wall of the connector causes an outward bulging of a peripheral edge of the connector as well as bulging of the opposite ends of the connector into a domed shape.

Abstract: A fluid coupling for connecting a plurality of fluid sources to a single-bore outlet member, said coupling comprising a plurality of tubes (44, 46, 48) mutually conjoined within a connector (42) for attachment of said outlet member, each said tube extending through said connector to terminate at a point (43) which is substantially contiguous with said outlet member when attached to said connector, the lumens of each said tube being mutually isolated by the tube walls until the termination of the tubes at said point, whereby in use of said fluid coupling with said single-bore outlet member connected thereto, fluid passing down any of said tubes discharges from the end of the respective tube substantially directly into the bore of said outlet member.

Abstract: A set for conveying blood between a patient and blood treatment apparatus such as a dialyzer. The set comprises a blood flow conduit, connecting with a patient's vascular system, and means for connecting the conduit with the dialyzer. A portion of the conduit comprises an enlarged-diameter, tubular pump segment connected at each pump segment end with a connector. The connectors also are each connected in substantially straight-line relation to other portions of the blood flow conduit. Typically, both connectors also each connect to a branch line in a relation substantially parallel to the connection of the other blood flow conduit portion and the connected tubular pump segment. Thus, the set is more capable of being rolled up and packaged in an automated manner, since it can be free of branching connections which connect at a substantial angle to the overall axis of the set.

Abstract: A family of variously configured, new, improved and universally compatible infusion sites and medical connectors that employ a recessed cannula and which function to interconnect uniquely configured T sites, Y sites, heparin locks and the like with a liquid source, such as an I.V. source.

Abstract: A drug delivery device is provided comprising a cartridge body including an upper portion defining a vial receiving area and terminating in a wall, the cartridge body including a cannula extending from the wall. A vial including a beneficial agent is coupled by a retaining member to the cartridge body in an inactivated position. The retaining member allows the vial to move to an activated position. The retaining member including an outer member and an inner member, the inner member separating from portions of the outer member as the vial moves from the inactivated position to the activated position.

Abstract: A normally-closed valve that can be easily connected and disconnected. Disposed in the fluid passageway through the valve is a cylindrical member that may be moved between an open position and a closed position. A spring holds the member in the closed position, and a leur-type cannula may be inserted into the valve to push the member into the open position. Two sealing rings are mounted around the cylindrical member. These rings prevent flow through the valve when the member is in its closed position. Two sets of channels are placed in the walls of the passageway to permit flow around the sealing rings when the member is in its open position.

Abstract: This invention provides apparatus and methods for aseptically transferring fluid into or out of a closed aseptic processing system. The apparatus comprises a novel fluid transfer station, including a needle bundle driver, a mounting base mounting the driver to a tank, and a fluid receiver assembly. The needle bundle driver includes a needle bundle holder which holds a needle bundle while the ends of the needles are driven into the tank through the fluid receiver assembly. The cooperation between the needle holder and the needle bundle includes a pair of clamp arms which extend outwardly from the needle bundle, and terminate in top and bottom pods. The top and bottom pods cooperate with the top surface of a support block and a bottom surface with an overhead clamping block, for locking the needle bundle into the needle holder, immobilizing the needle bundle between the clamping block and the support block.

Abstract: Disclosed is a connector for introducing medication into a patient in a safe, convenient way. It comprises a pair of plastic tubular members adapted to be manually pushed together to engage in a male-female relationship, and a locking mechanism that detachably secures the members together. The male member has a sealed entry port at its end, and the female member safely houses within it a needle which centrally pierces the seal of the port upon engagement of the members. Preferably, the locking mechanism provides a "click" sound when it locks the members together.

Abstract: The invention relates to a resealable port (2), or an injection site (24), for use with a syringe cone (16), the port being formed with a housing including a conduit (1) sealed by a resealable diaphragm (7) wherein a sealing annulus (6) is juxtaposed to, and interacts with, the diaphragm (7) to form an annulus and diaphragm assembly whereby the arrangement of the housing and the assembly is such that action of the syringe cone (16) as it passes through the diaphragm generates a cantilever action about a point (12) which serves to seal the diaphragm and the annulus in the housing.