Facile synthesis of self-assembled spherical and mesoporous dandelion capsules of ZnO: efficient carrier for DNA and anti-cancer drugs

This work presents a new facile strategy to fabricate self-assembled spherical and mesoporous submicronsized capsules, 'dandelions', of ZnO nanorods and nanoparticles. Self-assembled 'dandelion' capsules have been synthesized from Zn(Ac)(2) and Igepal CO-520, and the mechanistic approach for the growth of selfassembled ZnO capsules has been elucidated. Physical characteristics of the novel capsules responsible for biomedical applications have been studied through XRD, Raman spectroscopy, UV-Vis-NIR spectroscopy, XPS and EPR. The mechanical stability of the capsules has been characterized using high energy ultrasound with time in 10% PBS buffer. The biocompatibility of the capsules has been investigated with a cell-based study using normal lymphocyte and K562 cancer cells through MTT assay. The loading and release efficiency of the fluorescent molecules (Rhodamine 6G), anti-cancer drugs (doxorubicin hydrochloride, DOX), and deoxyribonucleic acid (DNA) have been investigated. All the results indicate the high potential of self-assembled ZnO 'dandelion' capsules in relevant applications, such as for sustained drug delivery with the formation of a {(ZnO)(n)(delta+)-(DOX)(m)} complex and gene delivery with the formation of a {(ZnO)(n)(delta+)-(DNA)(m) complex, in medical biotechnology. The fabrication of such self-assembled idiosyncratic capsules is very simple, feasible, and cost effective; moreover, it demonstrates improved performance in drug and gene delivery applications.