Microcarriers are small, solid support particles that play a vital role in cell culture, allowing for the growth of adherent cells in suspension-based bioreactor systems. Generally composed of materials such as dextran, collagen, polystyrene, gelatin, or glass, microcarriers offer a significant surface area for cell attachment while facilitating efficient nutrient and oxygen transfer. They are essential in modern bioprocessing, particularly for the large-scale production of biologics, vaccines, viral vectors, and advanced cell-based therapies.