Hydrogel hollow capsules were produced by chemical cross-linking of hydrogen-bonded poly(methacrylic acid) (PMAA)/polyvinylpyrrolidone layers deposited onto silica core followed by core dissolution. Chemical crosslinks of ethylenediamine (EDA) or adipic acid dihydrazide (AADH) within the capsule wall were introduced using carbodiimide (EDC) chemistry. Reversible capsule swelling can be controlled through variation of cross-linking agent. Unlike EDA- crosslinked capsules which are highly swellable at acidic and basic pH due to excess positive and negative charge in the capsule wall and have minimum size at pH 5.5, AADH-crosslinked capsules did not show swelling at low pH. Zeta-potential measurements of PMAA capsules crosslinked with AADH indicate existence of negative or no surface charge. Swelling degree of PMAA capsules crosslinked with the AADH crosslinker for the same time was higher than that for EDA-stabilized PMAA capsules. We found that pH-dependent swelling of PMAA hydrogel capsules crosslinked with AADH is significantly prolonged in time which can be used for sustained release applications.