Polyethylene terephthalate (PET) tubes commonly recognized as “red top tubes” are standard tubes used for the collection of blood samples for serum analysis. These tubes have internal coating and are not suitable for the preparation of platelet-rich plasma (PRP) or platelet-rich fibrin (PRF) which is then introduced back into the body. This internal coating negatively affects cellular components contained in PRP and PRF.
Silica microparticles coat the inner surface of these red top tubes. The silica promotes blood clotting. However, these silica particles are not designed for or suitable where preserving platelets and fibrin is crucial to tissue regeneration.
The cytotoxicity of silica coatings is due to the propensity of this compound to disrupt cell membranes and reduce cell proliferation.
Medical and dental fields have increasingly used platelet concentrates due to their regenerative potential. Choukroun invented and first used Platelet Rich Fibrin in the field of dentistry in France. The PRF required a simple glass tube to activate coagulation and the formation of a fibrin clot. However, the major manufacturers of plain glass tubes have discontinued their production. This caused a transition to the use of silica coated blood collection tubes as they are readily available.
In the laboratory, the silica microparticles used for the glass coating acts as an activator of the coagulation cascade. Thus, they are routinely used for blood collection in all labs across the world.
Silica dust is a known carcinogen causing lung silicosis and lung cancer. People generally consider amorphous silica to be less toxic. Manufacturers use it in various industrial products, such as additives in paints, varnishes, and glues. Silica is also used in production of powders, food stuffs and cosmetics. However, increasing studies have demonstrated that silica induces toxic effects on cells. The mechanism of its cytotoxicity is injury to the plasma membrane by silica dependent production of reactive oxygen species.
Judging from the accumulated studies and data, there is conclusive evidence that silica microparticles are hazardous in the human body.
This study examined the health hazards caused by silica microparticles derived from the platelet-rich fibrin matrix when using red top tubes.
Acute Cytotoxic Effects of Silica Microparticles on Human Periosteal Cells
Odontology 2020;108(4):545-552 PMID 31997225
The purpose of this study was to provide absolutely convincing evidence of the public health hazard caused by silica microparticles derived from platelet rich fibrin matrix.
Previous Study Findings
In a previous study, the same authors demonstrated using spectrophotometric and microscopic methods that silica microparticles detached from the inner wall of the glass and immediately incorporated into the PRF. (PMID 31248187)
Impact on Human Periosteal Cells
Researchers tested silica particles on the proliferation and viability of human periosteal cells. The silica microparticles significantly reduced cell viability at low dilutions. However, even when not diluted, the silica substantially inhibited growth. The periosteal cells absorbed the silica and incorporated some into the cytoplasm. This caused cytotoxic effects of membrane disruption and subsequent cell death. See the effects of silica microparticles on the migration and density of human periosteal cells form Figure 5 to the right.
Commercially available silica coated blood collection tubes contain cytotoxic silica microparticles. Silica microparticles incorporate into the resulting PRF matrix, and clinicians implant them to regenerate and repair injured tissues. This incorporation could plausibly hamper or disrupt tissue regeneration. Although clinicians have not reported any severe complications, we provide this data to alert them not to use this type of blood collection tube for Platelet Rich Fibrin preparation.
Striking Differences in Platelet Distribution Between PRF and Concentrated Growth Factors
Quote from this study:
“Silica nanoparticles were recently reported to induce cytotoxicity and inflammatory responses. The proposed mechanisms involve interactions between silica nanoparticles and the cell surface and the generation of reactive oxygen species. A recent report described that specific types of amorphous silic
a nanoparticles can act as tumor promoting substances. It is difficult to predict how silica nanoparticles ,that detach from tubes ,will influence the surrounding tissue and implantation sites. We found that silica microparticles obtained from silica coated tubes have substantial cytotoxic effects, we recommend that clinicians observe the manufactures caution of “in vitro use only” and not use silica coated tubes for PRF preparation.
Platelet Distribution Analysis
Figure 2. Summary of platelet distribution under various conditions. Asterisks mark wide-open spaces where platelets distribute sparsely. Double asterisks represent wider spaces than single asterisks. Bar scales are 200 µm.
Evidence for Contamination of Silica Microparticles
- Evidence for Contamination of Silica Microparticles in Advanced Platelet Rich Fibrin Matrices Prepared Using Silica Coated Plastic Tubes
Biomedicine 2019 Jun 19;7(2):45 PMID 31248187
Conclusion: Moreover, regardless of tube brands and individual donors, researchers found significant, though not accidental, levels of silica incorporated into the PRF matrix, and researchers will subsequently incorporate these into the implantation site. From increasing data for cytotoxicity of silica, we cannot exclude the possibility that such negatively influences tissue regeneration through induction of inflammation.
Figure 1: Macroscopic appearance of the silica-coated plastic tube (Neotube) pre- (a) and post-centrifugation (b).
Author note
Clinicians should never use these tubes in the production of Platelet Rich Plasma or Platelet Rich Fibrin. The FDA has not approved them; they cause cell death and are toxic to tissues. These tubes slow or prevent regeneration. If a malpractice case arises for any reason, clinicians cannot defend the use of non-approved and potentially toxic, non-FDA approved tubes
Juventix Regenerative Medical is an industry leader in the regenerative medical field. Our FDA-cleared Platelet Rich Plasma kits are manufactured for safety, sterility, and effectiveness. We scientifically manufacture our kits to provide a platelet concentrate, devoid of red blood cells, with a minimum number of leukocytes that are critical to the regenerative process.
Experience the Juventix difference and grab one PRP kit for just $24.99 using code PRPSample at checkout!
Juventix Regenerative Medical offers a LED Activator to activate the platelets and begin the regenerative process. Notably, LED light activates the platelets, triggering the release of cytokines, growth factors, and bioactive proteins from the alpha granules. As a result, this eliminates the need for chemical additives such as Calcium Chloride, Thrombin, or Collagen. Moreover, this method of LED light activation provides sustained growth factor release compared to older activation techniques, while also adhering to the FDA’s minimum manipulation standards.
Juventix Regenerative Medical supplies a patented Bio-Incubator to transform the Platelet Rich plasma into and Injectable Platelet Rich Fibrin. The Platelet Rich Fibrin, commonly called the ‘second generation of platelet products,’ has different cytokines and growth factors than the original PRP. As a result, these cytokines create an anti-inflammatory microenvironment, which is essential for stimulating regeneration in implant and restorative dentistry.
RESTORE, REVIVE, REGENERATE- JUVENTIX REGENERATIVE MEDICAL
Regenerative Regards,
Dr. Robert McGrath
