Medical Device Link.

Spotlight on Dispensers

Solvent dispensers are designed to bond polyvinyl chloride and ABS components used in medical devices. Three standard configurations are available with one, two, or four dispensing bushes. The user simply inserts the tubing or component into the appropriate bush and it is instantaneously ready for bonding. There is no need to rotate the tubing or component after it has been introduced into the device. The shape of the bush allows the solvent to be dispensed on external or internal tubing surfaces, conical surfaces, soft and rigid drip chambers, needles, and various types of connectors and components. The dispensers can be supplied with a vapour conveyor system to minimize environmental contamination. Medica S.r.l., Medolla (MO), Italy.

Digital dispensers that distribute up to 2, 5, or 10 ml of liquid feature a cam with precalibrated steps. Designed for single-handed operation, the Calibrex 520 is fitted with a volume-adjustment ring that has a click-stop mechanism to prevent volume alteration. Ergonomic features include a delivery jet that rotates 360° and an adjustable display window. The glass plunger, which is coated with scratchproof PVD, can be removed in seconds for cleaning. All dispensers bear a serial number and are individually tested. Adapters fit all commonly used reagent bottles. Socorex ISBA S.A., Ecublens, Switzerland.

A dispenser suited for medical solvent bonding is pneumatically driven to minimize explosion hazards. In addition, the SD7200 incorporates tight tolerances, PTFE seals, integral fluid paths, and solvent-impervious gaskets to reduce operator exposure to solvent vapour. The dispenser can be used on a wide range of external and internal diameters; it can also apply solvent simultaneously to the inside and outside of a part without requiring part rotation. The unit's volume-control mechanism combined with the use of porous materials in the application area prevent unwanted capillary filling even on very small inside diameters. The reservoir holds 1 L of solvent. Ventrex Inc., Ventura, CA, USA.

Precise, repeatable amounts of cyanoacrylate can be applied to catheter-marking bonds thanks to a dispenser's timed air-pulse mechanism. Fitted with a 0­15-psi regulator, the Model 1500XL-15 dispenser is able to accurately control air pressure at the lower settings required to dispense thin fluids. Repeatable dispensing times as brief as 0.001 second can be achieved. The adhesive is contained in a handheld barrel, minimizing fumes and spills, and crimped Teflon-lined tips ensure clog-free operation. EFD International Inc., Luton, Beds, UK.

A solvent dispenser consists of an HDPE bottle, a dispensing wick customized to the client's exact OD specifications, and a stainless-steel frame that can be adjusted to three different positions. The EZ-Bond dispenser applies a uniform coating of solvent to the outer diameter of the tubing or fitting. Because no dipping or blotting is required, throughput is increased, according to the company, and fumes and solvent usage are reduced. The bottle, which is designed to contain such solvents as cyclohexanone, is easy to clean and refill. The frame is equipped with rubber suction cups so that it can be firmly attached to the work surface. Lakeview Equipment Inc., Glenview, IL, USA.

Designed to meet the needs of immunodiagnostics manufacturers, a low-volume multireagent dispenser can accommodate up to 24 biological reagents. The Immunoblotter simultaneously dispenses reagents in dots or lines on a variety of substrates. Applications include dot blots, gene probes, EIA sticks, and related rapid diagnostic test formats. The company can also supply customized systems that dispense more than 24 reagents at a time. Biodot Ltd., Diddington, Cambs, UK.

A spray valve with a low-volume, low-pressure (LVLP) design deposits accurate and repeatable amounts of fluids for precision coating applications. Two microprocessor-controlled air inputs permit individual adjustment of the actuating and atomizing air, enabling the user to control dispensing in pattern diameters of 4­75 mm. Actuating air at 4.6 bar opens the valve, while LVLP air at 0.7 bar or less atomizes the fluid. Atomizing air continues for a few milliseconds at the end of the cycle to ensure a clean cutoff. Self-adjusting Teflon needle packings minimize maintenance; several nozzle and air cap options are available. Dosage 2000, Rueil-Malmaison, France.

A bottle-top dispenser with an eight-port disposable manifold is designed for smaller laboratories that cannot afford the time or expense involved in setting up a dedicated mechanized washing or dispensing system. Unlike multichannel pipettes that must be refilled after each single-row dispensing maneuver, the Stat-Matic can be attached to a large-capacity reservoir for continuous operation. Selectable volumes of 100, 200, or 250 µl are easily modified. The manifold delivers fluids with a row-to-row accuracy of 5%. Tri-Continent Scientific Inc., Sudbury, Suffolk, UK.