Surface-functionalized cockle shell–based calcium carbonate aragonite polymorph as a drug nanocarrier

Abstract

Calcium carbonate aragonite polymorph nanoparticles derived from cockle shells were prepared using surface functionalization method followed by purification steps. Size, morphology, and surface properties of the nanoparticles were characterized using transmission electron microscopy, field emission scanning electron microscopy, dynamic light scattering, zetasizer, X-ray powder diffraction, and Fourier transform infrared spectrometry techniques. The potential of surface-functionalized calcium carbonate aragonite polymorph nanoparticle as a drug-delivery agent were assessed through in vitro drug-loading test and drug-release test. Transmission electron microscopy, field emission scanning electron microscopy, and particle size distribution analyses revealed that size, morphology, and surface characterization had been improved after surface functionalization process. Zeta potential of the nanoparticles was found to be increased, thereby demonstrating better dispersion among the nanoparticles. Purification techniques showed a further improvement in the overall distribution of nanoparticles toward more refined size ranges <100 nm, which specifically favored drug-delivery applications. The purity of the aragonite phase and their chemical analyses were verified by X-ray powder diffraction and Fourier transform infrared spectrometry studies. In vitro biological response of hFOB 1.19 osteoblast cells showed that surface functionalization could improve the cytotoxicity of cockle shell-based calcium carbonate aragonite nanocarrier. The sample was also sensitive to pH changes and demonstrated good abilities to load and sustain in vitro drug. This study thus indicates that calcium carbonate aragonite polymorph nanoparticles derived from cockle shells, a natural biomaterial, with modified surface characteristics are promising and can be applied as efficient carriers for drug delivery.

Cockle Shell-Derived Calcium Carbonate (Aragonite) Nanoparticles: A Dynamite to Nanomedicine

“…The remaining 1.3% of the total mineral composition consists of other useful elements such as; oxygen (O), sodium (Na), phosphorus (P), potassium (K), zinc (Zn) etc. [4]. This clearly explains why water corals and sea shells are liable and applicable in nanotechnology.…”

“…CaCO 3 exists in three different kinds of crystalline polymorphs which are anhydrous in nature, they are; aragonite (needle-like), calcite (rhomboidal) and vaterite (spherical) as shown in Figure 1 [4,93]. The three different polymorphs vary in stability ranging from the most stable form which is calcite to the metastable forms which are vaterite and aragonite, these two readily metamorphosise into the stable polymorph [9].…”

“…In the quest to overcome some limitations associated with these therapeutic agents, the fast-growing field of nanotechnology focuses on diverse exploratory ways for researchers in the field of biomedical and pharmaceutical sciences. Advanced nanotechnology has paved ways for the use of convenient, affordable and noncomplex methods for synthesizing different nanoparticles from a range of abundant natural biomaterials and complex organic materials for industrial and medicinal purposes [4].…”

“…These important sea species mostly dwells in coastal area and it is a common important source of calcium carbonate (CaCO 3 ) with abundant biomaterials for biomedical purposes [12]. It has tremendous striking properties, also it is cheap and readily available with abundant high quality and pure CaCO 3 in aragonite polymorphic form, which is used in drug delivery [4].…”

“…It also possess a peculiar property of low thermodynamic stability thus, its size and shape are in concordance with the method and conditions of laboratory preparations [11]. In addition, numerous studies in recent years, were carried out on its toxicity to prove its wide safety margin both in vivo and in vitro [10,[16][17][18][19][20] A significant number of publications have appeared in recent years documenting the application of CSCaCO 3 NP of aragonite polymorph nanoparticles on different models of animals and cell lines for various therapeutic purposes with regard to their synthesis, functionalization, and both in vitro and in vivo toxicity studies [4,15,16,19,21,22]. Among all available documented literature on CSCaCO 3 NP with unique features so far, no review has been documented on the overview of this very nanoparticle of cockle shell biogenic origin.…”