The "single-use" concept came loaded with huge expectations of finding new solutions to address the needs of the changing
biopharmaceutical industry. Suppliers of single-use equipment have had difficulty living up to these expectations thus far,
partly because the expectations were not properly defined and partly due to intellectual property (IP) and supply-chain issues.
In a hard-piped manufacturing process, the bioprocessing flow path is only qualified once. With single-use technology, a new
flow path might be supplied various times, especially in multipurpose scenarios, and the qualification of the new flow's components
is often in the hands of the supplier. The supplier is urged to provide disposable flow paths using the same components and
properties for years to come.
Figure 3: Water-consumption percentage differences: Stainless steel versus single-use equipment (Data from Ref. 9).
To meet this request, however, the supplier must own all of the critical pieces of a particular assembly. For this reason,
many suppliers are aligning with, or acquiring, component suppliers and IP owners. Unfortunately, a lack of standards and
competition in this arena has promoted a vast array of equipment items, assemblies, and validation-procedure differences.
These varieties, marketing-driven product and validation claims cause more insecurities and questions, than solid standardized
Promising new development, in the form of single-use unit operations, is moving away from isolated technical solutions and
toward new, highly-integrated concepts. End-users of disposable bags for media initiated this trend in an effort to move from
a fixed process to a single-use process that includes mixing, filtration, temperature, recipe, and level control.
The integration of disposable sensors helped develop fully-disposable, cell-culture systems and opened the door for single-use
applications for most of the unit operations within a manufacturing process. New approaches are supplying single-use technology
platforms along the typical manufacturing process.
The application know-how determines the design of those platforms, but standardization of components such as tubing and connectors,
ensures interconnectivity at the same time. These concepts allow a clean and streamlined process with a unified automation,
control, and validation concept and, finally, a high level of operational excellence and security.
The single-use approach demands the highest level of technology integration possible. However, the economic and operational
advantages of the disposable option apply mostly to Green Field Facilities (i.e., facilities planned from scratch) with high-value,
low-volume products and might not be an option for existing manufacturing processes. This restriction to new facility design
is a purely economical one as most of the capital investments within existing processes are made and the equipment is written
off. Nevertheless, the flexibility of single-use manufacturing philosophy is attractive for expansion projects within existing
facilities. In addition, so-called "hybrid" systems merge the best out of both worlds by integrating single-use unit operations
such as buffer and media-hold steps, into existing production facilities.