Diffusion of fibroblast growth factor from a plaster of paris carrier

Abstract

Fibroblast growth factor (FGF) is a polypeptide that has been shown to have a stimulatory effect on osseous tissues in vitro. This study characterized the release of FGF from plaster of Paris (PLP) and measured the dissolution of PLP in various solutions with the aim of developing a reliable carrier system for the release of FGF in vivo. The study consisted of five experiments: (I) FGF diffusion from PLP pellets, (II) FGF diffusion from PLP discs, (III) PLP dissolution in saline, (IV) PLP dissolution in serum, and (V) FGF adsorption by commercially pure titanium. FGF was observed to be released at a rate directly proportional to the rate of dissolution of the PLP carrier, suggesting that either the FGF binds to the PLP; or, alternatively, the FGF may be entrapped by the PLP. Dissolution rate, and thus release rate, could be varied by varying the mass of the carrier. Greater diffusion of FGF was observed in larger, more slowly dissolving PLP carriers. Dissolution of PLP was observed to be slower in serum than in saline, apparently due to stabilization by factors in the serum but not due to a concentration gradient effect. Titanium coupons did not adsorb significant amounts of FGF. These results indicate that PLP, which has been shown in the past neither to aggravate inflammatory response nor to interfere with bone ingrowth, may serve as delivery vehicle for FGF to osseous tissues in vivo.

Antimicrobial Formulations of Absorbable Bone Substitute Materials as Drug Carriers Based on Calcium Sulfate

“…Several authors describe CaSO 4 as a carrier of bone morphogenetic protein (BMP) (29)(30)(31) as well as antibiotics (32)(33)(34)(35). Bai et al have tested BMP-loaded calcium sulfate in a clinical trial with 16 patients and successfully induced bone healing after prior nonunion of fractures (29).…”

Calcium sulfate

“…This proved the effectiveness of calcium sulfate as an antibiotic delivery vehicle. Rosenblum et al (1993) showed that fi broblast growth factor (FGF) was released at controlled rates from set CS cement disks, and that the FGF release was directly related to the dissolution rate of the CS cement. In a recent publication, Intini et al (2007) showed that a combination of CS and platelet-rich plasma was not only an effective bone repair material, but that it had osseoinductive properties similar to bone morphogenetic proteins.…”

Modulation of the resorption and osteoconductivity of α-calcium sulfate by histone deacetylase inhibitors

“…CS is completely resorbed following implantation and does not evoke a significant host response [1,2]. It can also be used as a delivery vehicle for growth factors and pharmacological drugs, including antibiotics [3,4]. Recently, CS was reported to modulate the expression of genes associated with osteoblastic phenotypes [5].…”

“…Because HDIs tend to be toxic at high doses, it is vital that therapeutic doses of HDIs be released in a sustained, but localized, manner. It is possible that HDI-containing aCS would consistently release HDIs during CS resorption, particularly as CS has excellent release characteristics [3,4]. Thus, the addition of HDIs to aCS could have a synergistic effect on bone regeneration, with few undesirable side effects.…”