Hydroxyapatite nanowhiskers embedded in chondroitin sulfate microspheres as colon targeted drug delivery systems

Abstract

An inorganic/organic hybrid material with triggering mechanism for specific drug delivery at colon is demonstrated. First, hydroxyapatite nanowhiskers (n-HA) with high aspect ratio, narrow particle size distribution and high surface area, ca. 67 m 2 /g, are prepared. As a proof-of-concept, terbinafine, a fungicidal agent, is loaded onto the n-HA, obtaining a drug loading of 40.63 mg of terbinafine per gram of n-HA. Hydroxyapatite nanowhiskers loaded with terbinafine are encapsulated with chondroitin sulfate (CS) microspheres, using chemically modified glycidyl methacrylate by performing ultrasonic microemulsion polymerization. The obtained hybrid materials were characterized by TEM, SEM, FTIR, and NMR. Dispersed n-HA in CS microspheres are obtained for different n-HA contents, from 1 to 10% (%w/w). Terbinafine release from hybrid microspheres is caried out by in vitro studies in simulated gastric fluid and simulated intestinal fluid. The studies demonstrated that sustained drug release can be obtained using the developed hybrid material.

A Review of Biodegradable Natural Polymer-Based Nanoparticles for Drug Delivery Applications

“…HAp prevents any toxicity effect during implantation, and its porous structure gives excellent diffusion properties. HAp is used in tissue engineering as a scaffold, in dental enamel repair, in medicine, for cancer cell treatment and as a bone cement [ 104 , 105 ]. A recent study investigated that HAp shows strong bonding due to its porous structure [ 106 ].…”

A brief review on hydroxyapatite production and use in biomedicine

“…Pores must be interconnected and have dimensions between 100 and 500 mm [48][49][50]. HAp may also be used as solid scaffolds for tissue reconstitution in tissue engineering to model compounds for biomineralization of human body [9,10], growth inhibition of many types of cancer cells [51], medicine supply [52], dental enamel repair [53], and injectable bone cement [54]. The mixture of HAp with other phosphates, such as β-tricalcium phosphate (β-TCP) and calcium pyrophosphate, provides greater applicability of this material, since it allows greater cell adhesion and osteogenic characteristics [55].…”

Preparation of Hydroxyapatite/Tannic Acid Coating to Enhance the Corrosion Resistance and Cytocompatibility of AZ31 Magnesium Alloys

“…However, the surface of the HA/TA/AZ31 is a brush-like array and porous ( Figure 1d). Compared with the direct formation of HA, tannic acid can induce a more uniform HA coating, which may be attributed to the increase in the number of the centers of HA growth [19,20]. The pores in the HA/TA coating may be caused by hydrogen evolution [23,31].…”

“…Furthermore, the mechanical properties and chemical stability of the directly-prepared coating are deficient [18]. To solve these problems, organic additives can be applied to induce and accelerate the growth of HA [19,20].…”