Can I pre-coat the culture plate to increase hydrogel attachment?

Although, for most cases, pre-coating the culture plate is not necessary, coating the plate with 1X PBS, Poly-D-Lysine solution, or 10-100 mM CaCl₂ can improve the hydrogel attachment. Please check the following protocols for coating the culture plate:

1. Add the PBS, Poly-D-Lysine solution, or CaCl₂ solution to the culture plate for 30 min.
2. Remove the PBS, Poly-D-Lysine solution, or CaCl₂ solution, and open the lid under the biosafety hood for 10-20 min before adding the hydrogel. The recommended volumes of PBS or CaCl₂ for different sizes of well plates are listed in Table 1 below.
   Table 1: Recommend volume of PBS, Poly-D-Lysine solution, CaCl₂ solution for pre-coating well plate