Physicochemical and biological profiles of a human donor plasma fractioning by-product

Background. By-products of human donor plasma fractionation often possess untapped potential for regenerative medicine. However, they are frequently excluded from further technological processing, and a comprehensive physicochemical and biological characterization remains lacking – a gap that hinders the development of novel, effective biomaterials. Objective. To perform an integrated physicochemical and biological analysis of fibrinogen-containing precipitate No. 1 (FР No. 1) – a by-product of donor plasma fractionation – and to evaluate its potential as a raw material for biomedical applications. Materials and Methods. A multi-method approach was employed, including Fourier-transform infrared (FTIR) spectroscopy, UV spectrophotometry, scanning electron microscopy (SEM), SDS‑PAGE electrophoresis, quantitative determination of protein mass fraction, assessment of fibrinogen extraction yield in citrate buffer and phosphate-buffered saline (37 °C, 5 hours), as well as in vitro biological testing on human dermal fibroblast cultures. Results. FP No. 1 was found to preserve the structural integrity of fibrinogen with low levels of impurities. The lyophilizate formed porous fibrin matrices with pore sizes ranging from 100 to 180 μm. Cell viability upon contact with the material reached 96.5 % (p 0.05), confirming the absence of cytotoxicity. The protein mass fraction in the dry substance was 77 %. Under optimal extraction conditions, the fibrinogen yield reached 21.9 % (citrate buffer) and 21.5 % (phosphate-buffered saline). Conclusion. FP No. 1 represents a highly promising secondary protein raw material for the development of bioinks for 3D bioprinting, wound dressings, and tissue-engineered constructs. These findings strongly advocate for the rational reintegration of plasma fractionation by‑products into high‑technology biomedical applications.