The time required for hybrid nanocomposite to gel must be consistent with the intended use. If it occurs too rapidly, it can impair efficient mixing of the constituents, or lead to needle clogging. Conversely, if gelation is too slow, the components may separate easily and flow away from the site of injection, nullifying any potential benefit of their combination. For example, in the case of a liposome-containing hydrogel designed for intramyocardial injection, the gelation time had to be compatible with the formation of a stable hydrogel within a beating heart. By mixing PAMB-Gel-TK and 4-arm-PEG-SG at 3 and 1.5% w/v, respectively, a satisfactory gelation within 30-50 s was achieved (Figure ). Figure . Gelation time of PAMB-Gel-TK/4-arm-PEG-SG hydrogels at different mixing ratio.