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08:49
Models of Bone Metastasis
Published on: September 4, 2012
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Potentiating bisphosphonate-based coordination complexes to treat osteolytic metastases
Gabriel Quiñones Vélez1, Lesly Carmona-Sarabia1, Waldemar A Rodríguez-Silva2
1Department of Chemistry, University of Puerto Rico, Río Piedras, San Juan, Puerto Rico 00931, USA. vilmali.lopez@upr.edu and Crystallization Design Institute, Molecular Sciences Research Center, University of Puerto Rico, San Juan, Puerto Rico 00926, USA.
Journal of Materials Chemistry. B
|February 26, 2020
Summary
Researchers developed novel bisphosphonate-based coordination complexes (BPCCs) using alendronate (ALEN) and bioactive metals. These new nano-sized BPCCs show enhanced cytotoxicity, offering improved drug delivery for bone disease treatment.
Area of Science:
- Materials Science
- Medicinal Chemistry
- Nanotechnology
Background:
- Alendronate (ALEN) is a clinically used bisphosphonate for bone diseases.
- Current formulations may have limitations in drug delivery and efficacy.
- Bisphosphonate-based coordination complexes (BPCCs) offer a novel approach to drug formulation.
Purpose of the Study:
- To synthesize and characterize novel bisphosphonate-based coordination complexes (BPCCs) using alendronate (ALEN) and bioactive metals (Ca2+, Zn2+, Mg2+).
- To investigate the structural, solid-state, dissolution, and cytotoxicity properties of these BPCCs.
- To explore nano-formulation strategies for enhanced drug delivery and therapeutic efficacy.
Main Methods:
- Hydrothermal synthesis of BPCCs with varying metal-to-alendronate ratios, temperatures, and pH.
- Single crystal X-ray diffraction for structural elucidation of five crystal forms.
- Dissolution studies in simulated gastric fluid and PBS, and cytotoxicity assays against MDA-MB-231 cells.
Main Results:
- Five distinct BPCC crystal structures were determined (ALEN-Ca forms I and II, ALEN-Zn forms I and II, ALEN-Mg).
- BPCCs exhibited pH-dependent degradation, with nano-emulsion synthesis yielding particle sizes down to 438 nm.
- Nano-sized ALEN-Ca BPCCs (nano-Ca@ALEN) demonstrated significantly higher cytotoxicity than bulk ALEN and ALEN-Ca crystals.
Conclusions:
- Novel BPCCs with tunable properties were successfully synthesized and characterized.
- Nano-sized BPCCs show promise for improved alendronate delivery and enhanced therapeutic effects.
- These findings support the development of advanced nano-formulations for treating bone-related diseases.
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