Opt 1ma 3000dv

Degradation rate is considered as the important factor for evaluation of bone graft and it was analyzed by monitoring for the weight loss of these samples by soaking in Dulbecco’s modified Eagle’s medium (DMEM, Caisson, North Logan, UT, USA) at 37 °C. These CS/CH-coated PLA mats were dried at 60 °C and a balance was used to measure their weight before and after the soaking. Each group had six samples at every time point. The Ca, Si, Mg, and P ions concentration released from composites on SBF were analyzed using an inductively coupled plasma-atomic emission spectrometer (ICP-AES; Perkin-Elmer OPT 1MA 3000DV, Shelton, CT, USA).

The design and size of the scaffolds are the same as that of the cell culture scaffolds that were immersed in cultured medium (#7501, ScienCell Research Laboratories, Carlsbad, CA, USA) at 37 °C. At 1, 3, 7 and 14 days, the medium collected and replaced with fresh medium. The Cu concentrations in the extracts were analyzed using inductively coupled plasma atomic emission spectrometry (ICP-AES; Perkin-Elmer OPT 1MA 3000DV, Shelton, CT, USA) and quantified the concentration of copper ions released by the scaffolds. Three independent studies were conducted and the averages were recorded.

The scaffolds were placed into tubes containing DMEM to assess for levels of hydroxyapatite formation in order to assess for bioactivity of the SrCS scaffolds. The tubes were placed into 37 °C incubators for various durations. The scaffolds were then removed from the tubes, rinsed with de-ionized water and pure alcohol and dried in an oven. The hydroxyapatite formation was then observed using SEM with methods as described above. In addition, ions released into the medium, such as Ca, Si, P and and Sr ions, were measured using an inductive coupled plasma-atomic emission spectrometer (ICP-AES; Perkin-Elmer OPT 1MA 3000DV, Shelton, CT, USA).

For this study, the various Si-containing FGelMa composited were immersed in simulated body fluid (SBF) to evaluate the weight loss and Si release profiles of the scaffolds over 14 days. The composition of SBF used in this study is similar to that of human plasma, and its formulated compounds include 7.9949 g NaCl, 0.2235 g KCl, 0.147 g K₂HPO₄, 0.3528 g NaHCO₃, 0.071 g Na₂SO₄, 0.2775 g CaCl₂, and 0.305 g MgCl₂·6H₂O. These compounds were dissolved in 1000 mL of distilled water in order, and tris buffer and HCl were added at the end to adjust the pH to 7.4. The scaffolds from each group were soaked in 37°C SBF for a fixed period of time, and the degradation rate was calculated using the following formula:

In addition, inductively coupled plasma atomic emission spectroscopy (ICP-AES, Perkin-Elmer OPT 1MA 3000DV, Shelton, CT, USA) was used to measure for the amount of Si ions released after periods of immersion.

CS were prepared as according to our previous published methods [27 (link)]. Commercially proven, analytically graded reagents were purchased from Sigma-Aldrich (Sigma-Aldrich, St. Louis, MO, USA). First, 70% calcium oxide (CaO) was mixed with 25% silicon dioxide (SiO₂) and 5% alumina oxide (Al₂O₃) and subsequently sintered at 1400 °C for 2 h and cooled to room temperature. The mixtures were placed into 99.5% ethanol and further ground with agate milling balls in a planetary ball mill machine (Retsch PM-100, Retsch GmbH, Germany) for 12 h. Then, the mixture was dried at 100 °C in an oven for 12 h. In addition, extracts of the CS powders were obtained following the revised version of the International Standard Organization (ISO/EN 10993-5). Briefly, a steam sterilization method was utilized to sterilize the CS powders before soaking in a tris-buffer (25 mM, pH = 8.5). After stirring for 24 h, the mixtures were filtered, and the supernatants were sterilized using a 0.2 μm filter. The Si concentration in the extracts were analyzed using inductively coupled plasma atomic emission spectrometry (ICP-AES; Perkin-Elmer OPT 1MA 3000DV, Shelton, CT, USA).

The Ca, Si, and P ion concentrations released from the CS on the different DMEMs were determined using an inductively coupled plasma-atomic emission spectrometer (ICP-AES; Perkin-Elmer OPT 1MA 3000DV, Shelton, CT, USA) after the samples had been immersed for specific periods of time. Three samples were then measured for each data point, allowing the results to be obtained in triplicate from three separate samples for each test.

The bioactivities of the Mg–CS/PCL scaffolds were considered by examining the formation of bone-like apatite on the specimens in simulated body fluid (SBF) solution. The scaffolds with a thickness of 10 mm and a diameter of 8 mm were immersed in SBF at 37 °C in a humidified atmosphere containing 5% CO₂ for various time-points with a surface-area-to-volume ratio of 0.1 cm²/mL without refreshing SBF. After various immersion time-points, the specimens were gently rinsed with ddH₂O to remove SBF and dried in vacuum at 50 °C. The surfaces of the immersed samples were observed by SEM. The Ca, Si, Mg, and P ion concentrations released from composites on SBF were analyzed using an inductively coupled plasma-atomic emission spectrometer (ICP-AES; Perkin-Elmer OPT 1MA 3000DV, Shelton, CT, USA).