This paper investigates the liquid absorbency potential of the vegetal cell-fibers (CF) of Luffa cylindrica (LC) in relation to their microscopic morphology. Absorption after drainage and centrifugation, involving deionized water and saline solutions, is measured on both the raw fibers of the vegetal net and the cell-fibers previously extracted from ligneous fibrous strands (FS) with NaOH-anthraquinone alkali treatment. The microspongy structure of the raw Fs-luffa, observed in the vegetal material by scanning electron microscopy (SEM), is formed by multicellular fibers (from 250 to 500) bonded together with a large lumen (5 to 30 μm) and containing small punctuations along the fibers as interconnections. Liquid absorption results show that this original structure of these promising fibers should contribute to good absorption capacity: 18.4g/g and 22.6g/g are respectively obtained with for broken raw FS and CF-luffa fluff treated by 5 wt % NaOH. Their absorption capacity for liquid improves with an additional formaldehyde treatment.

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Chitosan/hydroxyapatite composite microparticles were prepared by a solid-in-water-in-oil emulsification cross-linking method. The characteristics and activity in presence of simulated body fluid for 14 and 21 days were investigated. The size distribution, surface morphology, and microstructure of these biomaterials were evaluated. The scanning electron microscopy revealed an aggregate of microparticles with a particle size, ranged from 4 to 10 μm. The deposited calcium phosphate was studied using X-ray diffraction analysis, Fourier transform infrared spectroscopy, and inductively coupled plasma/atomic emission spectroscopy analysis of phosphorus. These results show that the mineral, formed on microparticles, was a mixture of carbonated hydroxyapatite and calcite. Scanning electron microscopy revealed that calcium phosphate crystals growth was in form of rods organized as concentric triangular packets interconnected to each other by junctions. Interaction between chitosan and growing carbonated hydroxyapatite and calcite crystals are responsible for a composite growth into triangular and spherical shapes. The results demonstrated that these microparticles were potential materials for bone repair.

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