How can the cell attach to cell culture plate? I know there are two reasons. First, electrostatic reaction second, extracellular matrix but need more explanation.
Tissue culture plastic is plasma treated to oxidize the surface. This promotes adsorption of extracellular matrix proteins, principally from the serum, but also cell-derived ECM proteins at later times of culture. Cells do not have receptors for polymers such as plastic, so cannot interact directly with a synthetic substrate unless it is coated with an adhesive protein or peptide.
Tissue culture plastic is typically treated with a polymeric protein or polypeptide. Flasks and well plates are usually ready to use and have most often been coated by the manufacturer with α-poly-L-lysine, a homopolypeptide. Some researchers prefer to use products untreated well plates, petri dishes, etc. and treat them themselves using an extracellular matrix protein such as collagen Type I, fibronectin or vitronectin. The cells are able to attach to this via integrins and other cell surface receptors.