Abstract
Aggregate is one of the most extensive existing modes of matters in the world. Besides the research objectives of inanimate systems in physical science, the entities in life science can be regarded as living aggregates, which are far from being thoroughly understood despite the great advances in molecular biology. Molecular biology follows the research philosophy of reductionism that generally reduces the whole into parts to study. Although reductionism benefits the understanding on molecular behaviors, it encounters limitations when extending to aggregate level. Holism is another epistemology that is comparable important to reductionism, which claims a top-down method to explore objectives at aggregate or mesoscale level, emphasizing on the interactions and synergetic/antagonistic effects of a group of composed single entities in determining the characteristics of a whole. As a representative of holism, aggregation-induced emission (AIE) materials have made great achievements in the past two decades in both physical science and life science. In particular, the unique properties of AIE materials endow with in-situ and real-time visual methods to investigate the inconsistence between microscopic molecules and macroscopic substances, offering researchers excellent toolkits to study living aggregates. The applications of AIE materials in life science are still in its infancy and worth expanding. In this perspective, we summarize the research progresses of AIE materials in unveiling some phenomenon and processes of living systems, aiming to provide a general research approach from the viewpoint of holism. At last, insights in what we can do in the near future are also raised and discussed.