Low Pressure Biofilm Devices

Low Pressure Biofilm Device (LPMR-series)

The standard for small-scale laboratory analysis, this Modified Robbins Device can be machined from virtually any material, although the norm is acrylic or PVC. The LPMR-12 and the LPMR-25 contain, respectively, 12 or 25 individual ports in a linear array along a channel of rectangular cross-section. Each port accepts a press-fit plug holding a sample coupon with a surface area of 50 mm˛ (typically stainless steel, although coupons may be made from almost any material). The design of the plug is such that the surface of the coupon essentially becomes part of the channel wall. Bacteria introduced into the fluid stream adhere to the coupon and ultimately establish a biofilm, which may then be removed for analysis. These devices are intended for low-flow applications with a maximum pressure rating of 15 psi (100 kPa).

Electrical Low Pressure Biofilm Device (LPMR-12E)

Machined from non-conductive plastics (typically acrylic or PVC) to the same basic design as the LPMR-12 and contains 12 individual ports. Depending on the conductivity of the sample coupon, one or two platinum electrodes run through the primary bore, and each coupon holder is designed for electrical contact, so that a weak alternating electric field may be established to influence biofilm growth.

The LPMR-series is essentially a modification of the original Robbins device, with press-fit plugs sealed by a radial O-ring. The mid- and high-pressure Tyler systems (of which there are many different types) have screw-in plugs sealed by an axial O-ring. This type is capable not only of higher pressures and flow rates, but provides superior positioning of the coupon in the laminar flow region of the manifold.