Targeting and Dissolution Characteristics of Bone Forming and Antibacterial Drugs by Harnessing the Structure of Microspherical Shells from Coral Beach Sand

Abstract

Pharmaceutical drugs for the treatment of metabolic bone diseases lead to a number of side effects due to the their uncontrollable dispersion throughout the body.1 Therefore, many groups directed their research to develop devices that are targeted to specific organs or tissues and release the encapsulated drug in a highly regulated way.2–7 The development of completely resorbable bone‐filling biomaterials delivering drugs would offer a therapeutic approach of drug release and bone augmentation in a simple one‐step process.8–11 The biomaterials selected needs custom designs, to control the quantity and the duration of drug release and at the same time inducing desirable host cell responses and preventing bacterial infection.12–15 Current synthetic biomaterials produced as drug delivery microspheres due to production difficulties contain not very well designed interconnected pores and fail to fill these pertinent requirements. Turning directly to nature such as marine structures for inventive solutions can help to solve these problems due to their structure, chemistry and architecture and their unique designs.16–20 We demonstrate ‐for the first time‐ the potential of unique coral shells with specific microspherical structure and highly organised interconnected intra‐pore designs to offer a number of desired functions for targeted delivery of Bisphosphonate (BP) (paminodrate) and an antibiotic (Gentamicin) for bone regeneration, repair and preventive antibacterial slow drug delivery.

The effectiveness of the controlled release of simvastatin from β-TCP macrosphere in the treatment of OVX mice

“…The focus of this research was to develop a simvastatin drug delivery system utilizing Foraminifera exoskeletons hydrothermally converted to β‐TCP as the carrier material. This design is motivated by the unique structural properties of Foraminifera, which posses a uniformly distributed and interconnected porous network (Chou et al ., ) within the material that will allow more consistent drug loading and steady drug release rates. In addition, an apatite coating was made to ‘slow’ the release of simvastatin.…”

Development and dissolution studies of bisphosphonate (clodronate)-containing hydroxyapatite-polylactic acid biocomposites for slow drug delivery

“…Briefly, coral powder was mixed with the required amount of diammonium hydrogen phosphate [(NH 4 ) 2 HPO 4 ] to obtain HAp and then converted in a Parr reactor at 250°C and 8.0 MPa pressure. Coral has been characterized previously (Ben‐Nissan et al ., ; Cegla et al ., ; Chou et al ., ; McCutcheon et al ., ). Hydrothermally converted coralline hydroxyapatite was loaded with 25% w/w clodronate by dissolving the required amount of clodronate in purified 18 MilliQ water (Millipore), mixed with HAp, sonicated and then allowed to dry in a Rotavapor R‐210 coupled with a vacuum controller (V‐850, BUCHI, In Vitro Technologies, Australia) at 60°C.…”

Trace elemental imaging of coralline hydroxyapatite by laser-ablation inductively coupled plasma-mass spectroscopy

“…The coral ( Porites ) samples were collected from the Great Barrier Reef, Australia, and was cleaned in bleach and sonicated in ultra‐pure water for 20 min to remove any organic residues. The coral samples were cut into 1 × 1 cm slices, converted to 100% coralline hydroxyapatite by the hydrothermal method and characterized as described in previously published methods (Chou et al ., ).…”