Facile green synthetic approach of bio inspired polydopamine coated diatoms as a drug vehicle for controlled drug release and active catalyst for dye degradation

• Published in: Microporous and mesoporous materials 2019-11, Vol.288, p.109572, Article 109572
• Main Authors: Uthappa, U.T., Kigga, Madhuprasad, Sriram, G., Ajeya, Kanalli V., Jung, Ho-Young, Neelgund, Gururaj M., Kurkuri, Mahaveer D.
• Format: Article
• Language: English
• Subjects: Bioinspired materials; Diatoms; Drug delivery; Nanocatalysis and dye degradation; Polydopamine
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2019.109572

Researchers are extensively working on the development of a single material that could be used in multiple applications. In this study, the surfaces of natural diatoms (DE) were modified with bio-inspired polydopamine (PDA). The curcumin (CUR) has been used as a model drug and loaded to pristine DE followed by a coating of PDA which acts as a barrier/gatekeeper. Target ligand folic acid (FA) was tagged with DE-CUR-PDA for targeted drug delivery applications. In vitro drug release studies demonstrated at pH 1.2 for pristine DE-CUR 87.67% and 74.82% of drug was released for DE- CUR-PDA-FA. Also, at pH 7.4 for pristine DE-CUR 67.53% and 51.90% of drug release was realised for DE-CUR-PDA-FA. The decrease in drug release was due to the thin PDA layer coated on DE which acts as a barrier/gatekeeper by controlling the drug release rate. The obtained results suggested that the DE-CUR-PDA-FA could be used as one of the potential anticancer drug delivery system for targeted drug release in tumour therapy. Further, DE-PDA in the absence of drug was decorated with silver nanoparticles (AgNPs) in-situ to get DE-PDA-AgNPs and used as nanocatalyst for the catalytic application. The designed nanocatalyst was used for the degradation of cationic and anionic dyes. Both, the cationic methylene blue (MB) and anionic congo red (CR) dyes showed rapid degradation within 8 min and with better recyclability. [Display omitted] •Bio-inspired polydopamine (PDA) coated on naturally available diatoms (DE).•Polydopamine served as a barrier/gatekeeper by controlling the drug release rate.•PDA facilitated to tag target ligand for targeted drug delivery applications.•In-situ growth and uniform distribution of AgNPs on DE-PDA was achieved.•DE-PDA-AgNPs showed rapid degradation within 8 min for both anionic and cationic dyes and with better recyclability.