# Mg-Hydroxyapatite Nanorods for Dual Intracellular Doxorubicin Delivery and Osteogenic-Associated BM-MSC Responses

## TL;DR

This paper explores Mg-doped hydroxyapatite nanorods for delivering doxorubicin to cancer cells and improving interactions with stem cells.

## Contribution

The study introduces Mg2+ doping in hydroxyapatite nanorods to enhance drug delivery and cell compatibility.

## Key findings

- Mg2+ doping increases cell compatibility and interaction with bone marrow-derived stem cells.
- Mg-doped nanorods improve doxorubicin binding and release in osteosarcoma cells.
- Mg2+ induces structural disorder, increasing reactive surface sites for better functionality.

## Abstract

Intracellular drug
therapies are based on the use of nanocarriers
that can successfully penetrate cell barriers and release therapeutic
payloads directly inside the cell environment. In this context, hydroxyapatite
(HA) nanoparticles provide a particularly promising platform owing
to their inherent biocompatibility, bioactivity, and drug-binding
capability. This work hence examines anisotropic HA nanorods (NRs),
synthesized using hydrothermal methods, with a particular focus on
Mg-to-Ca ion substitution, aiming to increase the bioactivity and
improve the interaction with therapeutics, specifically targeting
intracellular sustained release. Our findings indicate that increasing
the extent of Mg doping in apatite NRs induces enhanced cell compatibility
and interaction with primary human bone marrow-derived mesenchymal
stem cells. Moreover, the doping with Mg2+ enhances the
NRs capacity to link and release doxorubicin, a widely used antitumor
drug, in human osteosarcoma cells. The enhanced functionality is attributed
to the Mg2+-induced structural disorder at the NR surface,
which reduces the crystallinity and increases the number of reactive
surface sites. As a result, Mg2+ doping has emerged as
a promising strategy for optimizing the functional performance of
apatite-based nanocarriers, highlighting their potential applications
in nanomedicine and precision medicine.