Novel polysaccharide hybrid scaffold loaded with hydroxyapatite: Fabrication, bioactivity, and in vivo study

© 2018 Elsevier B.V. The main goal of this study was to produce a novel porous scaffold for rapid in vivo bone healing behavior. Lyophilization technique was used to produce this highly porous hybrid scaffold from Na-alginate (S) and hydroxyethylcellulose (HEC) impregnated with different concentration of hydroxyapatite (HA). After cross-linking the scaffolds, their incubation was carried out in simulated body fluid (SBF) for 4 weeks at 37 °C to investigate their bioactivity. A number of techniques were employed (e.g., XRD, FTIR, SEM, EDX, and texture analyzer) to characterize the designed scaffolds. It was observed that the mechanical properties of the scaffolds increase deformation energy (182 ± 16 J/m3) and rigidity gradient (19.44 ± 0.85 Pa) after loading with HA. Furthermore, the scaffolds were implanted in femur critical size defects (2 mm) of adult male Wistar rats for 6 weeks. In vitro and in vivo analyses demonstrated impressive bioactivity and biocompatibility for the prepared scaffolds, especially those containing HA. Based on the obtained results we conclude that the designed scaffolds are promising solutions for bone regeneration applications

Pharmaceutical particulates and membranes for the delivery of drugs and bioactive molecules [Editorial]

The delivery of drugs and bioactive molecules using pharmaceutical particulates and membranes are of great significance for various applications such as the treatment of secondary infections, cancer treatment, skin regeneration, orthopedic applications and others [...]

Novel zinc-silver nanocages for drug delivery and wound healing: Preparation, characterization and antimicrobial activities

Metal organic framework (MOF)-nanocages (MOF-NCs) in the form of zinc-based nanoparticles (NPs) were synthesized as drug carriers for the purpose of wound healing. The prepared NCs (single and bi-metallic with silver-MOF) were based on zinc and they were loaded with ascorbic acid (vitamin C) as a model drug which accelerates wound healing. The NCs were then investigated by several characterization techniques such as XRD, TEM, FTIR and BET surface area. Furthermore, the release behavior of the loaded ascorbic acid from the developed NCs was measured in phosphate buffer solution (PBS). NCs antibacterial activity was tested against strain of gram-positive bacteria (Staphylococcus aureus ATCC- 29213, Streptococcus pyogenes ATCC-19615 and Bacillus subtilis ATCC-6633), gram-negative bacteria strain (Pseudomonas aeruginosaATCC-27853and Escherichia coli ATCC-25922) and fungi (Candida albicans ATCC-10231).The physicochemical features of the NCs were confirmed by the results obtained from XRD and FTIR measurements. The particle size of the NCs was confirmed to be in the range of 30–50 nm. Prolonged drug release that was combined with impressive antibacterial activities, and good wound healing rates were also recognized for the zinc based NCs in comparison to commonly used Ag NPs. It is concluded that the current NCs are potentially suitable for wound healing and drug delivery applications

Influence of Niobium Pentoxide particulates on the properties of Brushite/Gelatin/Alginate membranes

Novel non-porous membranes were prepared by impregnating of nano-brushite and niobium pentoxide (Nb2O5) into a gelatin/alginate matrix. The physicochemical properties, morphology and mechanical properties of the prepared membranes were characterized using XRD, FTIR, SEM, TEM and universal testing machine, respectively. Swelling ability of the prepared membranes was determined in distilled water. The surfaces of the membranes were characterized by means of FTIR and SEM coupled with EDX after submersion in simulated body fluid (SBF) up to 15 days. Moreover, the calcium and phosphorus ion concentrations in the SBF were measured by UV-spectrophotometer. The in vitro drug release and the release mechanism of a model antibiotic, namely, ciprofloxacin (CFX), were tested in phosphate buffer saline (PBS) for 15 days. The antibacterial activities of the CFX-loaded membranes were tested against known microorganisms. The physicochemical properties, morphology, mechanical properties and swelling ability of the prepared membranes were found to be dependent on the presence of Nb2O5 allowing control of their properties. For example, the Nb2O5-loaded membranes exhibited a higher in vitro bioactivity and slower drug release compared to those of Nb2O5-free membranes. The CFX-loaded membranes also exhibited an excellent inhibition zones against the selected microorganisms. Overall, the prepared membranes have been found to be very promising for use in bone substitute’s applications

Nanoparticle- and nanoporous-membrane-mediated delivery of therapeutics

Pharmaceutical particulates and membranes possess promising prospects for delivering drugs and bioactive molecules with the potential to improve drug delivery strategies like sustained and controlled release. For example, inorganic-based nanoparticles such as silica-, titanium-, zirconia-, calcium-, and carbon-based nanomaterials with dimensions smaller than 100 nm have been extensively developed for biomedical applications. Furthermore, inorganic nanoparticles possess magnetic, optical, and electrical properties, which make them suitable for various therapeutic applications including targeting, diagnosis, and drug delivery. Their properties may also be tuned by controlling different parameters, e.g., particle size, shape, surface functionalization, and interactions among them. In a similar fashion, membranes have several functions which are useful in sensing, sorting, imaging, separating, and releasing bioactive or drug molecules. Engineered membranes have been developed for their usage in controlled drug delivery devices. The latest advancement in the technology is therefore made possible to regulate the physico-chemical properties of the membrane pores, which enables the control of drug delivery. The current review aims to highlight the role of both pharmaceutical particulates and membranes over the last fifteen years based on their preparation method, size, shape, surface functionalization, and drug delivery potential