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Using N-vinylimidazole as the reactant and introducing different ether-based side chains pH/salt dual-sensitive poly(imidazole ionic liquid) gel (P[CnOC2vim]Cl, n=1, 2, 3) was designed and synthesized. The structure characteristic of the gel was determined by IR spectra and SEM. The swelling ratio of gel under different conditions was investigated, including releasing property for ciprofloxacin (CIP) and berberine (Ber). The results showed that P[CnOC2vim]Cl(n=1, 2, 3) gel exhibits typical pH-sensitivity and salt-sensitivity. Its swelling ratio increased first and then decreased, and reached the maximum when the value of pH was 7.4; the swelling rate is smaller under the higher concentration of the NaCl. Furthermore, P[COC2vim]Cl gel with the short ether chain has the highest release rate of CIP and Ber at pH=7.4, the release behavior is in accord with the first-order kinetic equation. With the increase of the side chain of ether group, the cumulative release rate of P[CnOC2vim]Cl(n=2, 3) gel to CIP and Ber decreased obviously, and the behavior comforts to Higuchi kinetic equation. The results suggest that P[CnOC2vim]Cl(n=1, 2, 3) gel is the pH/salt dual-sensitive potential carrier for controlled drug release.