Medical Design Briefs - May 2021 - 9

healthcare industry. Within the hospital setting, plastics can be
used in consumables like syringes and tubing, medical-grade
gloves, and even trays and cups used by patients. Each product
represents an opportunity to reduce the amount of nondegradable waste produced by the hospital.
Two main types of bioplastics have dominated this infant market - PLA [polylactic acid] and PHA [polyhydroxyalkanoate].
PLA is produced using the sugars found in corn starch, cassava,
or sugarcane. Depending on the specific manufacturing process, the end product can be made to mimic traditional plastics
like polyethylene, polystyrene, and polypropylene. PLA is especially promising due to its biocompatibility - making it a natural candidate for applications in medical implants, orthopedic
devices, and drug-delivery systems. PLA has even played an
important role in the global pandemic, being utilized as 3D
printable polymer for ventilator components and in the form a
filament to manufacture personal protective equipment (PPE).4
PHA is a biopolymer that is actually created by microorganisms that convert organic material into a polymer byproduct.
In its harvested state it can be utilized for many medical consumables, most notably for surgical sutures and meshes.
Taking a broader view of hospital waste, PHAs are ideal candidates to be used for single-use food-grade packaging. These
are just two of the most common bioplastics being produced
today, but research is ongoing to identify alternative materials
that balance performance and degradability. Hospital-wide
initiatives and leadership-backed support will be required to
supplant the use of traditional plastics with bioplastics in a
range of end use applications.
It is worth taking some time to briefly define the terminology related to degradability. One might intuitively assume
that all biopolymers are able to be composted, but this is not
necessarily the case. Most experts place all plastics and bioplastics into three categories of degradation: degradable,
biodegradable, and compostable. Even traditional plastics
can be defined as degradable, which simply means that over
some amount of time and the appropriate environmental
conditions, they will disintegrate into microscopic fragments.
This is the source of the microplastics that have become a
serious issue for most bodies of water.
Most bioplastics fall into the category of biodegradable, but
there are still some gray areas, as the term does not have an
agreed upon set of requirements. Typically, biodegradable
means that microorganisms like bacteria and certain fungi
can convert the material into water, carbon dioxide,
methane, biomass, and inorganic compounds. This process
can usually occur within a few months, but those that take
longer are given the designation of durable bioplastics. The
term compostable refers to bioplastics that are converted completely into nutrient-rich biomass with no toxic byproducts. As
an example, PLA can be composted and will produce 70 percent fewer greenhouse gases as it degrades than petroleumbased plastics.5 Globally, standards are being developed to better define these terms. Both ASTM D6400 and ISO 17088
include definitions for compostability, for example.
Validation and Testing
The biomedical industry is easily one of the most highly
regulated in the world and, as such, significant validation and
testing is required to introduce a new product or even utilize
a new material for an existing product. Standards organizations like ASTM and ISO typically lag behind innovation
Medical Design Briefs, May 2021

MINIATURE Solenoid-Operated
Pinch & PTFE Isolation Valves
1

1 Pinch & Media Isolation Valves
2 Pneumatic Pinch Valves

3 NEW! Electronic Proportional

Pressure & Flow Controls

4 NEW! " Eclipse " Proportional

Isolation Valves

5 " DR-2 " Miniature Precision

Regulators

6 Electronic Valves Ideal for Oxygen

Applications

Medical Design Briefs - May 2021

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