Poloxamer 407, also known as Pluronic F127, is a triblock copolymer that consists of a central hydrophobic polypropylene oxide (PPO) block flanked by two hydrophilic polyethylene oxide (PEO) blocks. It is a commonly used surfactant and emulsifying agent in pharmaceuticals and various other industries. Here are some details about its chemical structure and physical properties:
Chemical Structure of Poloxamer 407:
Poloxamer 407 has a chemical structure that can be represented as follows:
(PEO)99-(PPO)67-(PEO)99
In this representation, “(PEO)” stands for the polyethylene oxide block, and “(PPO)” stands for the polypropylene oxide block. The numbers indicate the average number of repeat units in each block.
Physical Properties of Poloxamer 407:
Molecular Weight: The molecular weight of Poloxamer 407 can vary, but it typically falls within the range of approximately 12,600 to 14,600 g/mol.
Appearance: Poloxamer 407 is a white to off-white, waxy solid at room temperature.
Solubility: It is soluble in both water and many organic solvents. Its solubility in water increases with temperature.
Cloud Point: Poloxamer 407 exhibits a cloud point, which is the temperature at which it undergoes a phase transition from a clear solution to a turbid or cloudy solution. The cloud point of Poloxamer 407 in water is typically around 23-25°C.
Gel Formation: Poloxamer 407 is known for its ability to form gels at relatively low concentrations, especially when dissolved in cold water. These gels are thermally reversible, meaning they can be turned into a liquid upon heating and revert to a gel upon cooling.
Viscosity: Poloxamer 407 solutions can exhibit a substantial increase in viscosity as the concentration of the polymer increases. This property makes it useful in various formulations, including pharmaceuticals and personal care products.
Surfactant Properties: Poloxamer 407 acts as a non-ionic surfactant, making it useful for emulsification and solubilization of hydrophobic compounds in aqueous solutions.
Biocompatibility: Poloxamer 407 is generally considered biocompatible and is used in various pharmaceutical applications, including drug delivery systems and as an excipient in oral and topical formulations.
Toxicity: In general, Poloxamer 407 is considered safe for use in pharmaceuticals and cosmetics. However, like any chemical, it is important to consider the specific formulation and usage, as there may be variations in toxicity based on concentration and other factors.
It’s important to note that the exact properties of Poloxamer 407 can vary depending on factors such as molecular weight and processing conditions. Its versatility and relatively low toxicity make it a widely used polymer in various industries.