Poloxamer 407

[9003-11-06]

This product is an α-hydro-ω-hydroxypoly(oxyethylene)a-poly(oxypropylene)b-poly(oxyethylene)a block copolymer. It is formed by the reaction of propylene oxide and propylene glycol to produce polyoxypropylene glycol, followed by the addition of ethylene oxide to form the block copolymer. In the copolymer, the number of oxyethylene units (a) is 101, the number of oxypropylene units (b) is 56, the oxyethylene (EO) content is 71.5% to 74.9%, and the average molecular weight ranges from 9840 to 14600.

【Description】 This product is a white to slightly yellow translucent waxy solid with a slight peculiar odor. It is easily soluble in water and ethanol, soluble in anhydrous ethanol or ethyl acetate, and almost insoluble in petroleum ether.

【Identification】 The infrared absorption spectrum of this product should be consistent with the reference spectrum (Spectrum Set 618).

【Tests】 Acidity or alkalinity Dissolve 1.0g of the product in 10ml of water, and determine as required (General Rule 0631). The pH should be between 5.0 and 7.5. Water content Determine as per the water determination method (General Rule 0832, Method 1). The water content should not exceed 1.0%. Residue on ignition Should not exceed 0.4% (General Rule 0841). Heavy metals Dissolve 1.0g of the product in 23ml of water, add 2ml of acetate buffer (pH 3.5), and examine as required (General Rule 0821, Method 2). The heavy metal content should not exceed 20 parts per million. Arsenic salt Dissolve 1.0g of the product in 5ml and 23ml of water with shaking, and examine as required (General Rule 0822, Method 1). It should comply with the regulation (0.0002%). 

【Category】 Pharmaceutical excipient, solubilizer, and emulsifier, etc. 

【Storage】 Store protected from light in a tightly closed container. Appendix: Preparation of solution Dissolve 50g in 900ml of methanol containing 0.5ml of glacial acetic acid, dilute to 1000ml with methanol, and mix well. If it appears yellow, it should not be used; if cloudy, it should be filtered. If it remains cloudy or yellow after filtration, it should not be used. This solution should be prepared freshly before use and stored in a brown bottle in a dark place. Preparation and standardization of phthalic anhydride-pyridine solution Add 72g of phthalic anhydride to 500ml of pyridine (the water content of pyridine should be less than 0.1%; or take 500ml of pyridine, add 30g of phthalic anhydride, dissolve, and then distill, using the middle fraction). Shake vigorously until completely dissolved or heat in a water bath at 40°C to complete dissolution. Protect from light and let stand overnight. Pipette 10ml of the above solution accurately, add 25ml of pyridine and 50ml of water, mix well, and let stand for 15 minutes. Add 0.5ml of phenolphthalein-pyridine solution (1→100), and titrate with sodium hydroxide (0.5mol/L). The consumption of titrant should be between 37.6ml and 40.0ml.