Bio-inLine® Biofilm Reactor
A Modified Robbins Device Built for Lab and Light Industrial Research
The Bio-inLine® Biofilm Reactor (IBR) is a Modified Robbins Device (mRD) designed for in-line biofilm growth, sampling, and monitoring from within a working fluid system. Rather than culturing biofilm in a separate bench-top reactor, the IBR installs directly in-line so that biofilm develops on removable coupons under the actual flow conditions of the system being studied. Individual coupon holder plugs can be removed one at a time for sampling without shutting down flow, making time-course biofilm studies and ongoing monitoring practical at the lab or pilot scale. The IBR is rated to 100 psi and is available in PET or 316 stainless steel construction.
The IBR 500 holds 12 standard 12.7mm disc coupons (the same format used in the CDC Biofilm Reactor® and Rotating Disk Biofilm Reactor), giving researchers access to the full range of 40+ BST disc coupon materials without needing a separate coupon format. The half-inch internal channel matches standard half-inch fluid pipe geometry so that flow conditions inside the reactor reflect those of the connected system. The reactor body is sealed with silicone rubber O-rings and is fully autoclavable and reusable.
IBR 500-PET
The standard IBR is machined from black PET and includes twelve nylon coupon holder plugs, PET coupons, and a coupon removal tool. Alternate coupon materials are available from the same 40+ material selection used across all BST disc coupon formats.
Reactor Components
The IBR consists of twelve nylon coupon holder plugs threaded into a PET or stainless steel lid. Each plug holds a standard 12.7mm diameter disc coupon and can be removed individually for sampling during an experiment. The lid and coupon assembly mounts to a body containing a half-inch internal channel, matching standard half-inch fluid pipe geometry to ensure flow conditions reflect the system being studied. The entire chamber is sealed with silicone rubber O-rings and rated to 80 psi of fluid pressure.
Applications
The IBR is suited for any research or quality control application where biofilm needs to be grown, sampled, or monitored from within a flowing system rather than a standalone reactor. Primary applications include drinking water distribution system research, food and beverage processing line biofilm monitoring, pharmaceutical purified water and WFI system qualification, and light industrial process water studies. The in-line format makes it straightforward to study how changes in flow rate, temperature, disinfectant concentration, or pipe material affect biofilm development under real operating conditions rather than approximated bench conditions.
The IBR is also well suited for microbiologically influenced corrosion (MIC) research in laboratory and pilot-scale piping systems. MIC studies require tracking biofilm development and corrosion progression on specific materials over defined time intervals, a task that depends on being able to sample individual coupons without interrupting flow. The 316 stainless steel version (IBR 500-316) is the appropriate choice for harsher chemistries, elevated temperatures, and industrial environments where PET construction is not suitable, and supports coupon materials relevant to MIC research, including carbon steel, stainless steel, and copper.
Because the IBR uses the same 12.7mm disc coupon format as the CDC Biofilm Reactor® and Rotating Disk Biofilm Reactor, it integrates naturally into multi-reactor study designs. Biofilm grown in the IBR under in-line conditions can be compared directly against biofilm grown under high shear batch conditions in a CDC reactor or medium shear continuous flow conditions in the RDR, using identical coupon materials across all three systems.
IBR 500-10
These nylon Coupon Holder Plugs hold a half-inch standard disc coupon. Twelve are included with each IBR.
IBR 500-316
The 316 stainless steel version is designed for industrial environments, harsher chemistries, and elevated temperature applications where PET construction is not suitable.
IBR 250
The IBR 250 is a compact variant of the IBR 500 for labs and installations where space is limited. At 13.75 inches overall length with 9 coupon positions, it fits tighter bench setups and existing fluid systems where the full-size reactor may not be practical. It shares the same half-inch in-line design, 100 psi rating, and coupon format as the IBR 500, and all IBR 500 accessories are fully compatible. Available in PET (IBR 250-PET) and 316 stainless steel (IBR 250-316).
Modified Robbins Device Design
The Modified Robbins Device is one of the oldest and most well-established formats for in-line biofilm sampling, originally described by McCoy, Bryers, Robbins, and Costerton in 1981 and widely used since in drinking water, industrial, and clinical biofilm research. The mRD format allows coupon surfaces to be positioned flush with the inner pipe wall so that biofilm grows under the same hydrodynamic conditions as the surrounding pipe material, with minimal flow disruption. BST’s implementation refines the original design with improved coupon holder geometry and a dedicated removal tool, making individual coupon extraction reproducible and aseptic. The IBR is designed for lab bench and pilot-scale installations rather than high-pressure field deployments, with a 100 psi working pressure appropriate for most laboratory fluid systems, water distribution research setups, and light industrial process lines.
