Sodium Hydroxypropyl Starch Phosphate is a chemical compound, a pre-gelatinised starch that enables stable emulsions to be prepared.

The name defines the structure of the molecule

• "Sodium". It's an alkali metal, symbol Na, with atomic number 11. It's an essential element for life and plays a key role in regulating blood pressure and plasma volume.
• "Hydroxypropyl". Indicates the presence of a hydroxypropyl group, which is a derivative of propylene alcohol.
• "Starch". It is a polysaccharide of plant origin used as an energy reserve by plants. It is composed of numerous glucose units linked together.
• "Phosphate". Indicates the presence of a phosphate group, which is an ester of phosphoric acid.

Description of the raw materials used in its production:

• Starch - A natural polysaccharide, commonly obtained from corn or potatoes.
• Hydroxypropyl Chloride - A reagent used to chemically modify the starch.
• Sodium Phosphate - A sodium salt that is used to introduce phosphate groups into the modified starch.

Industrial chemical synthesis of Sodium Hydroxypropyl Starch Phosphate, step by step:

• Starch Modification - The starch is treated with hydroxypropyl chloride in the presence of a base (usually sodium hydroxide), causing substitution of some of the hydroxyl groups of the starch with hydroxypropyl groups.
• Phosphorylation - The hydroxypropylated starch is then treated with sodium phosphate, which introduces phosphate groups into the polymer.
• Neutralization - If necessary, the reaction is neutralized by adding an acid or a base.
• Purification - The product is purified to remove impurities; this might include filtration, washing, and separation.
• Drying - The purified product is dried to remove residual water.

What it is used for and where

Food

It is a chemical component that controls viscosity in food products.

Cosmetics

Viscosity control agent. It controls and adapts viscosity to the required level for optimal chemical and physical stability of the product and dosage in gels, suspensions, emulsions, solutions. 

Bulking agent. It regulates the water content, dilutes other solids, can increase the volume of a product for better flow, acts as a buffer against organic acids, helps to keep the pH of the mixture within a certain level.

Abrasive agent. It contains abrasive particles to remove stains or biofilm that accumulate on the stratum corneum or teeth. Baking soda, kieselguhr, silica and many others have abrasive properties. Peeling or exfoliating products used in dermatology or cosmetic applications contain abrasive agents in the form of synthetic microspheres, however these microspheres or abrasive particles are not biodegradable and create pollution in aquatic ecosystems.

Commercial applications 

Thickening Agent in Cosmetic Products. Sodium Hydroxypropyl Starch Phosphate is used to increase the viscosity of cosmetic products, such as lotions and creams.

Emulsion Stabilizer. It helps to stabilize emulsions in skin and hair care products, preventing the separation of components.

Hair Conditioning Agent. Used in shampoos and conditioners to improve the manageability and softness of hair.

Rheology Modifier. Alters the viscosity of cosmetic products, allowing for better application and feel on the skin.

Suspending Agent. Used in skin and hair care products to keep solid particles, such as pigments or exfoliating agents, suspended.

The most relevant studies on this ingredient have been selected with a summary of their contents:

The aim of the present study was to investigate the effects of hydroxypropyl-distarch phosphate (HDP) supplementation on postprandial energy metabolism and glucose-dependent insulinotropic polypeptide (GIP) in human subjects. A total of ten healthy male subjects, with a mean BMI of 23·6 (SEM 1·3) kg/m(2), age 35·2 (SEM 1·9) years and body weight 71·1 (SEM 4·0) kg, participated in a randomised, cross-over, intervention study with two different test meals (1673·6 kJ) containing either waxy maize starch or HDP from waxy maize starch (degree of substitution 0·154, P content 0·004 %). Resting energy expenditure (REE) and blood concentrations of various biomarkers were measured at fasting and up to 180 min postprandially. Indirect calorimetry showed that the HDP meal caused higher REE (P < 0·05) and fat utilisation (P < 0·001) than the waxy maize starch meal. The HDP meal led to significantly lower postprandial glucose (P < 0·05), insulin (P < 0·05) and GIP (P < 0·05) responses than the waxy maize starch meal. Both postprandial REE (R - 0·576, P < 0·01) and fat utilisation (R - 0·514, P < 0·05) were negatively correlated with the postprandial GIP response, but not with the glucose and insulin responses. In conclusion, dietary supplementation with HDP lowers postprandial GIP and increases postprandial REE and fat utilisation in healthy humans. An HDP-rich diet may therefore have beneficial implications in weight management. Further studies are required to confirm the efficacy in overweight or obese subjects, and to determine the precise mechanisms (1).

In this study male rats were fed a fiber-free, purified diet containing either gelatinized tapioca starch that was not modified chemically (TS, 50 g/kg diet) or gelatinized chemically modified tapioca starch (CMS, 50 g/kg) for 21 d. TS was used as the control. The six kinds of gelatinized hydroxypropyl distarch phosphate (HDP) from tapioca with two different degrees of substitution (DS) and three different degrees of cross-linking (DC) were used as CMS sources. The wet weight and moisture of fecal output of the rats fed HDP with higher DS were 100 and 20% greater than that in the control rats, respectively. The weights of cecal wall and cecal contents were also 30 and 50% higher in the rats fed HDP with higher DS than those in the control rats. The pH of the cecal contents was more acidic in the rats fed HDP with higher DS than that in the control rats. Fecal excretion of bile acids was 40% higher in the rats fed HDP with higher DS than in the control rats. These effects of HDP were only slightly affected by the DC. The plasma cholesterol concentration was 16% lower in the rats fed HDP with higher DS and highest DC than in the control rats. The concentrations of liver lipids and plasma triglycerides and the cecal pool of organic acids were not affected by diet. The apparent absorptions of Ca and Mg were not affected by diet, but those of Zn and Fe were 75 and 70% lower in the rats fed HDP with higher DS than in the control rats. These results suggest that the physiological effects of HDP depend on the DS but not on the DC (2).

The aqueous two-phase system (ATPS) with polyethylene glycol (PEG) and hydroxypropyl starch (HPS) was evaluated for the extraction of human immunoglobulin G (IgG) from human serum albumin (HSA). The partitions of IgG in PEG/sulphate, PEG/phosphate, PEG/Dextran and PEG/HPS ATPSs were compared, and the results indicated that PEG/HPS system was most suitable for IgG extraction. The effects of the concentrations of PEG, HPS and NaCl addition and pH on the partition of IgG and HSA in PEG/HPS ATPS were investigated. It was found that with 15% NaCl addition at pH 8.0 IgG could be largely recovered in the top PEG-rich phase and most of HSA kept in the bottom phase. In addition, the response surface methodology (RSM) was used to optimize the extraction of IgG from the protein mixture of IgG and HSA. The optimal conditions were obtained as 12% (w/w) PEG 4000, 18% (w/w) HPS and 10% (w/w) NaCl at pH 8.0. The extraction yield of IgG in the top phase was 99.2% and the purification factor could reach 5.28. The back extractions of IgG into a phosphate-rich bottom phase were also studied. The total purification factor was 5.73 with the yield of 84.0%. The results indicated that PEG/HPS ATPS might be a promising alternative for the primary recovery of IgG from the complicated feedstock (3).

CAS    221355-22-2

DTXSID901021985

Synonyms :

• Starch, phosphate, 2-hydroxypropyl ether, sodium salt

References_________________________________________________________________________

(1) Dietary supplementation with hydroxypropyl-distarch phosphate from waxy maize starch increases resting energy expenditure by lowering the postprandial glucose-dependent insulinotropic polypeptide response in human subjects.

Shimotoyodome A, Suzuki J, Kameo Y, Hase T.

Br J Nutr. 2011 Jul;106(1):96-104. doi: 10.1017/S0007114510005854. 

(2) Hydroxypropyl-distarch phosphate from Tapioca starch reduces zinc and iron absorption, but not calcium and magnesium absorption, in rats.

Kishida T, Nakai Y, Ebihara K.

J Nutr. 2001 Feb;131(2):294-300.

(3) Evaluation of poly(ethylene glycol)/hydroxypropyl starch aqueous two-phase system for immunoglobulin G extraction.

Wu Q, Lin DQ, Yao SJ.

J Chromatogr B Analyt Technol Biomed Life Sci. 2013 Jun 1;928:106-12. doi: 10.1016/j.jchromb.2013.03.020.