In the present manuscript, a brief overview on barium, its possible utilization, and the aftermath of its behavior in organisms has been presented. A number of studies have exhibited both the unwanted outcome barium displayed and the advantages of barium laden compounds, tested in in vitro and in vivo settings. The plethora of prospective manipulations covered the area of hydrogels and calcium phosphates, with an end goal of examining barium’s future in the tissue engineering. Can barium be used as a substitute for other biologically relevant divalent cations? Will the incorporation of barium ions hamper the execution of the essential processes in the organism? Most importantly, can the benefits outweigh the harm?
|Characteristics||Barium||Barium Acetate||Barium Carbonate||Barium Chloride||Barium Hydroxide||Barium Oxide||Barium Sulfate|
|Melting point, °C||725||41||1740 (α form, at 90 atm)||963||78||1923||1580|
|Boiling point, °C||1640||No data||Decomposes||1560||550||2000||1149|
|Water solubility||Forms barium hydroxide||No data||0.02 at 20 °C,
0.06 at 100 °C
|375 at 20 °C||56 at 20 °C,
947 at 78 °C
|38 at 20 °C,
908 at 100 °C
|0.00222 at 0 °C,
0.00413 at 100 °C
|Specific gravity||3.5 at 20 °C||No data||4.43||3.856 at 24 °C||2.18 at 16 °C||5.72||4.5 at 15 °C|
|Swelling and Thermal Stability||Mechanical Stability|
|Alginate barium beads (600 kD) ||No data||Stability of alginate beads increased by replacing calcium for barium.
With low concentrations and intensive rinsing of barium beads, no barium leakage was observed
|Sodium-Alginate-based hydrogels ||Swelling degree (ϕ) (13–19% in deionized water and 12–17% in NaCl 0.15 mol/L) lower than with Ca2+ and Sr2+
Crosslinking agent and the effective crosslinking degree have not significantly influenced the thermal behavior of sodium-alginate hydrogels
|Compressive modulus (G) substantially higher than with Ca2+ and Sr2+ (53.8–121 kPa in deionized water and in NaCl 17.9–85.4 kPa)
Effective crosslinking degree considerably higher than with Ca2+ and Sr2+ (outer, fast crosslinking obstructed ion diffusion and presented a step to a homogenous structure)
|Alginate-based films containing natamycin ||Significant decrease in the water uptake for barium crosslinked films was observed.
Ca-Ba films were more hydrophobic than Ba-Ca films
|Ba2+ ion crosslinked films were brittle and revealed a wrinkly, whitish appearance, rougher to the touch|
|Alginate/polyacrylamide ||Swelling ratio was reduced||Stronger gel network was formed.
BaFe-1/8-w (original weight ratio of sodium alginate to acrylamide of 1/8 equilibrated with water solution) showed a slight decrease in the tensile strength and the stiffness compared with BaFe-1/8-s (equilibrated with salt solution)
Semi-crosslinked Ba-Alg network, due to weak interaction between Ba2+ and COO− on the M blocks and unpaired G blocks, contributing to the weaker strength and tensile stress
|Alginate-Based Microcapsules ||No data||Microcapsules (crosslinked with 0.5% BaCl2) were imperfectly spherical, mainly elliptical, moderately broken, with an irregular surface, demonstrating many exposed cells in the outer part of the structure
1% or 1.5% BaCl2 gelling solutions displayed significantly better morphological characteristics