AbstractIt is well known that metal objects perturb electromagnetic fields. Therefore, a conventional metal microdialysis probe cannot be used to determine the bioeffects of electromagnetic radiation. Using fused‐silica tubing, we developed an inexpensive nonmetallic, rigid microdialysis probe for use in electromagnetic radiation research or during magnetic resonance imaging. This probe has a concentric tube design, with the membrane length adjustable to the size of the area to be dialyzed. The probes tested had regenerated‐cellulose membranes that were 3 mm in length. This report describes how to make this probe. Average relative recovery rates at flow rates of 2.0, 1.0, and 0.5 μl/min were 21%, 27%, and 42%, respectively. These rates were slightly lower than the 30%, 42%, and 68% obtained with the commercially available metallic CMA10 microdialysis probe with a 3 mm membrane. This may be due to the fused‐silica probe and CMA10 probe being made with different types of dialysis membranes. © 1995 Wiley‐Liss, Inc.