RESUMEN
Spirograph is a geometric drawing that produces mathematical roulette curves of the variety technically known as hypotrochoids and epitrochoids. This paper presents a research on a novel Spirograph Based Mechanical System (SBMS) meant for the production of electrospun mat with near uniform characteristics for wound dressing applications. A combination of natural (Chitosan) and artificial (Polyethylene oxide) polymer, along with Aloe vera plant extract has been evaluated as a material for wound dressing application. The improvement in the mechanical property, in vitro and in vivo studies indicate developed SBMS compared to the typical collectors has been found suitable for producing electrospun mat for wound dressing applications.
Asunto(s)
Aloe/química , Materiales Biocompatibles/química , Quitosano/química , Polietilenglicoles/química , Animales , Antiinfecciosos/química , Antiinfecciosos/farmacología , Línea Celular , Colágeno , Femenino , Ratones , Pruebas de Sensibilidad Microbiana , Análisis Espectral , Resistencia a la Tracción , Cicatrización de HeridasRESUMEN
Nanocrystalline apatites with different Ca/P ratios were synthesized using eggshell as a calcium source by microwave processing. The apatites were found to have a minor amount of Mg, Sr, Si and Na ions inherited from the eggshells. The presence of several foreign ions results in a perturbed lattice structure indicated by an increase in lattice constants and shift in vibrational frequencies of the functional groups. The apatites were heat treated to investigate the influence of foreign ions on thermal stability. The minor amounts of ions do not affect the thermal stability. The differences in thermal behaviour of these apatites were due to the presence of HPO(2-)(4) ions only and not due to other ions because of their low content.
Asunto(s)
Apatitas/química , Calcio/química , Animales , Pollos , Calor , IonesRESUMEN
The eggshell waste has been value engineered to a nanocrystalline hydroxyapatite (HA) by microwave processing. To highlight the advantages of eggshell as calcium precursor in the synthesis of HA (OHA), synthetic calcium hydroxide was also used to form HA (SHA) following similar procedure and were compared with a commercially available pure HA (CHA). All the HAs were characterized by X-ray powder diffraction (XRD) method, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and specific surface area measurements. Nanocrystalline nature of OHA is revealed through characteristic broad peaks in XRD patterns, platelets of length 33-50 nm and width 8-14 nm in TEM micrograph and size calculations from specific surface area measurements. FT-IR spectra showed characteristic bands of HA and additionally peaks of carbonate ions. The cell parameter calculations suggest the formation of carbonated HA of B-type. The OHA exhibits superior sinterability in terms of hardness and density than both SHA and CHA may be due to larger surface area of its spherulite structure. The in vitro dissolution study shows longer stability in phosphate buffer and cell culture test using osteoblast cells establishes biocompatibility of OHA.
Asunto(s)
Materiales Biocompatibles/síntesis química , Durapatita/síntesis química , Nanopartículas/química , Animales , Línea Celular , Cáscara de Huevo/química , Cáscara de Huevo/ultraestructura , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanopartículas/ultraestructura , Osteoblastos/citología , Difracción de Polvo , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de SuperficieRESUMEN
Rapid synthesis of calcium deficient hydroxyapatite (CDHA, Ca(10-x)(HPO4)x(PO4)(6-x)(OH)(2-x)) with Ca/P ratio 1.5 was done by precipitation using calcium nitrate tetra-hydrate and phosphoric acid and subsequently subjecting to microwave irradiation in a domestic microwave oven for 15 min. Transmission electron microscopy analysis shows needle like morphology of CDHA having length 16-39 nm and width 7-16 nm. The synthesized CDHA has the characteristic HPO4(2-) vibration band at 875 cm(-1) in Fourier transform infrared (FT-IR) spectra. The X-ray powder diffraction (XRD) analysis shows a pattern corresponding to stoichiometric hydroxyapatite (HA) with broad peaks suggesting that CDHA particles were nanosized. Fourier transform Raman spectroscopy (FT-Raman) do not indicate any fluorescence band that is characteristic of non-stoichiometric HA. The thermal decomposition of CDHA to beta tricalcium phosphate (beta-TCP) was also studied for the additional confirmation. The nanosized CDHA was found to be stable up to 600 degrees C.