Macroduct Sweat Collection Testing Method:

After cleaning the selected area of skin on the patient, the electrodes with Pilogel discs installed are attached to the patient's arm with the provided straps. Pressing RUN on the Webster Sweat Inducer activates Iontophoresis. If everything is normal the current flow reaches its peak at about 20 seconds as pilocarpine iontophoresis begins.

Sweat stimulation occurs under the positive electrode while the disc under the negative electrode completes the electrical circuit. Reliable, uniform, gel-to-skin contact ensures delivery of pilocarpine over the whole skin area, thus providing total gland stimulation and maximal sweat yield.

After iontophoresis, the electrodes are removed, and a Macroduct Sweat collector is firmly attached to the stimulated skin site. The base of the sweat gland is 2 to 3 mm beneath the surface of the skin. Fluid secreted by the gland creates hydraulic pressure that moves the fluid upward through the sweat duct to emerge from the skin as sweat. When sweat surfaces beneath a Macroduct collector, the secreted sweat is directed to the orifice and into the plastic "macroduct" tubing.

After attachment, sweat becomes visible in the spiral tube of Macroduct within one to four minutes, depending on the relative elasticity of the skin and the subjects sweating rate. The emergent sweat is turned blue by contact with a small amount of blue water soluble dye applied to the Macroduct collection surface This allows easy assessment of the sweat volume at any time during collection.

When collection is completed, the spiral tubing is severed from the Macroduct base and the sweat specimen is introduced into the Sweat-Chek analyzer or expressed into a storage cup for chloride analysis at a later time. A typical Macroduct sweat collection produces many times the sweat volume needed for analysis.

The Sweat-Chek Sweat Conductivity Analyzer with its temperature controlled measurement cell, flow through operation and wide range digital readout, is a modern adaptation of a proven analytical method. Dr. Lewis Gibson, one of the worlds leading authorities on sweat testing, commented on Sweat Chek: "If this machine is kept clean, it gives results that are every bit as reliable as an analysis for sodium or chloride.

Discovery Diagnostics
Canadian Customers
if you wish to speak to a Discovery Diagnostics sales representative or customer service, for information about Macroduct Sweat Collection System Model 3700 , please call Toll Free within Canada: 1-888-883-9101.Outside Canada, click here for ordering information.