Osteotropic polypeptide nanoparticles with dual hydroxyapatite binding properties and controlled cisplatin delivery

Area of Science:

• Biomaterials Science
• Nanotechnology
• Oncology

Background:

• Nanoparticles with extended bone residence are crucial for effective bone disease therapies.
• Developing targeted drug delivery systems for bone cancers remains a significant challenge.

Purpose of the Study:

• To synthesize a simple nanoparticulate system with both anticancer and hydroxyapatite binding properties.
• To explore the potential of this system for bone cancer treatment applications.

Main Methods:

• Amphiphilic copolymer poly(γ-benzyl-glutamate)-block-poly(glutamic acid) (PBLG-b-PGlu) nanoparticles were synthesized via ring-opening polymerization and nanoprecipitation.
• Characterization included cisplatin interaction, association, release kinetics, hydroxyapatite binding, and cytotoxicity assays in prostate cancer cell lines.

Main Results:

• Successfully prepared ~50 nm PBLG-b-PGlu nanoparticles exhibiting dual hydroxyapatite binding and anticancer properties.
• Nanoparticles complexed cisplatin (6.2% w/w loading) with release triggered by chloride ions over 14 days.
• Demonstrated in vitro hydroxyapatite binding and significant cytotoxic effects on prostate cancer cell lines that metastasize to bone.

Conclusions:

• Cisplatin-loaded PBLG-b-PGlu nanoparticles show potential as effective carrier systems for treating bone metastases.
• The dual functionality of hydroxyapatite binding and targeted drug delivery offers a promising therapeutic strategy.