Technical Textiles in Bioprocessing

As in most industries, consumer demand is driving the rapid pace of growth in this field. Also contributing to the expansion in the medical arena is the availability of new material technologies. These include high-performance applications, new textile developments, and new production process and techniques. This means new possibilities for replacing metal and plastic rigid devices with stronger, lighter -- and often cheaper -- flexible alternatives.

By definition, technical textiles are materials and products manufactured primarily for their technical and performance properties rather than their aesthetic or decorative characteristics.  In the medical field, they incorporate current materials and technologies, such as synthetic fibers, with traditional medical devices and applications to create a new category of beneficial products. Today, cell-based therapies are emerging as a promising strategy to treat genetic, degenerative, and immunological diseases. This innovation in medical science relies on next-generation technology to produce them in a safe and cost-effective manner.

What Drives the Technical Textile Market?

All of the innovations listed above lead textile engineers and designers to explore and invent a much wider range of technical products and foresee their potential uses. But while the new developments and insights are coming quickly, the end user ultimately determines the success or failure of a product. In other words, the market decides. 

Factors affecting material selection for design process:

• Physical and chemical properties
• Mechanical properties
• Cost and availability
• Fabrication and processing
• Lifetime and sustainability
• Adaptability with other materials
• Performance and function

According to Tamer F. Khalifa in Textile Science & Engineering, "Technical textile design is a structured engineered creative process where one of the major challenges for technical textile designers is the compromise of all these needs, parameters, and requirements in a design that fulfill the purpose." The article goes on to stress the essential elements in the design phase are establishing a design framework to address all requirements and parameters of the end product.

By clearly setting design goals at the start, every project is then guided by a detailed, well-planned blueprint for a better chance of success.

One of the emerging technologies in medicine is cell therapy. While stem cells have the potential for the production of cells for cell therapy, this bioprocessing is not without significant challenges - namely safety.

Upstream Bioprocessing

In this case, living cells or their components (bacteria, enzymes, chloroplasts) are used and cultured in a controlled laboratory process to obtain desired end products.

The upstream process encompasses the steps from early cell isolation and cultivation, to cell banking and culture expansion. It ends with the final harvest and collection of a live cell batch.

Challenges within the process:

• clear idea and design of the product 
• selection of producing organism
• scalability of culture apparatus
• raw material acquisition and availability
• type of bioreactor
• media development
• monitoring fermentation
• purification of product for desired quality

Examples of technical textiles utilized in upstream bioprocessing are flexible membranes, sensors, filters, and plasticized PVC bags.

Downstream Bioprocessing

This phase involves processing the cell mass from upstream in order to meet quality and purity requirements. After final harvest, the desired product is obtained via centrifugation, filtration, or cell disruption.

Challenges within the process:

• biomass-product separation
• damage to the cells
• product purification
• concentration, crystallization, drying 
• fill-finish
• storage stability/properties
• field trials
• FDA approval and product license
• marketing and sales

Examples of technical textiles found in downstream bioprocessing include textile scaffolds, single-use bag assemblies, personal protective equipment (PPE) for medical professionals, and improved hygiene products.

To assure a successful end result to the bioprocessing endeavor, thorough planning is key. It should be envisioned as an integrated process designed to take all parts into account, from start to finish. Ideally, it will yield the quantity and quality of product desired using the fewest number of steps, done in the most cost-effective manner.

Additional Biomedical Applications of Technical Textiles

• Artificial cornea
• Artificial heart and heart valves
• Artificial kidney, lung, liver
• Artificial joints
• Artificial tendon, ligament
• Artificial skin
• Contact lenses
• Surgical sutures
• Surgical disposables