Hydrogel capsules show attractive prospects in drug delivery recently because of high drug loading and sustained release behavior. In this study we reported a simple and convenient route to fabricate poly(acrylic acid)-poly(N-isopropylacrylamide)(PAA-PNIPAm) hydrogel capsules by using hydroxypropylcellulose-poly(acrylic acid)(HPC-PAA) complexes as the templates. The capsules showed a high drug loading(～280% to the weight of capsules) for Doxorubicin hydrochloride. The release of drug from the capsules was responsive to the temperature and p H of the surroundings, showing a low-rate but sustained release behavior favorable for low-toxic and long-term therapy. Together with the convenient preparation, high drug loading, dual responsivity as well as the sustained release feature, it is implied that this polymeric hydrogel capsule might be a promising candidate for new drug carriers.
