Paper Title
METHODOLOGY FOR EVALUATING THE BIOCOMPATIBILITY OF THIN LAYERS AND COLORED MATERIALS

Abstract
Biocompatibility is a critical factor in the development of materials for medical devices, particularly next-generation biomaterials such as graphene-based biosensors, semiconductors, and modified PEDOT (poly(3,4-ethylenedioxythiophene)) films. These materials exhibit unique electrical, mechanical, and chemical properties, making them highly attractive for biomedical applications. However, ensuring their compatibility with biological systems is essential to prevent adverse effects such as cytotoxicity, inflammation, or poor tissue integration. Traditional cell viability tests, such as MTT or Alamar Blue, are unsuitable for these materials due to issues like opacity or color interference. This work presents a comprehensive approach for biocompatibility assessment of thin films and other advanced materials using flow cytometry as a reliable and high-throughput analytical tool, in accordance with ISO 10993-5 guidelines for cytotoxicity testing. Flow cytometry enables precise measurement of cell viability[1], apoptosis, and immune response markers after exposure to advanced materials. Both short-term (24 hours) and long-term (up to 15 days) exposure periods were evaluated to capture immediate and delayed cellular responses. We outline an approach that integrates in vitro cytotoxicity testing and cell-surface interaction studies to evaluate the biological responses of cells exposed to these materials. Our method was applied to graphene-based films, semiconductor pigments, and modified PEDOT materials to demonstrate its effectiveness in quantifying biocompatibility across a range of novel substrates. Results from this methodology provide insights into the safe implementation of these advanced materials in medical devices, ensuring they meet the necessary standards for human health and regulatory approval. This approach offers a valuable framework for the systematic assessment of biocompatibility in the development of new materials for biomedical applications. Keywords - Viability, Biocompatibility, ISO 10993-5, Semi Conductors, Thin Films, Graphene