AquaSolve™ hypromellose acetate succinate (hydroxypropylmethylcellulose acetate succinate or HPMCAS)

AquaSolve HPMCAS for pharmaceutical applications is a cellulosic polymer with four substituents randomly substituted on the available hydroxyl groups with the following mass content: methoxyl, 12–18 wt%; hydroxypropoxy, 4–23 wt%; acetyl, 2–16 wt% and succinoyl, 4–28 wt%. It is white to off-white in color and has a faint acetic acid-like odor and a barely detectable taste. 

AquaSolve HPMCAS is available in several grades for pharmaceutical applications varying in extent of substitution of acetyl and succinoyl groups, and in two particle sizes (fine or granular). AquaSolve HPMCAS is used as a polymeric carrier in solid dispersions for solubility enhancement of poorly soluble drugs. The amphiphilic nature, high glass transition temperature (Tg) and low viscosity in various solvents of this polymer are some of the unique properties that make it ideal for use in spray-dried dispersion formulations.

In oral pharmaceutical formulations, AquaSolve HPMCAS is commonly used as an enteric film coating for tablets, capsules or granules. For aqueous film-coating purposes, a dispersion of HPMCAS fine powder and a plasticizer (such as triethyl citrate) in water is commonly used. Organic solvents are also vehicles for applying this polymer as a film coating. HPMCAS can form films without the addition of water or solvents.

Other pharmaceutical applications include its use alone or in combination with other soluble or insoluble binders in the preparation of granules with sustained drug-release properties, where the release rate is pH-dependent.

Explore other products:  Excipients, Specialty Ingredients

Application Information




Controlled-release Formulations

Enteric coatings made from hypromellose acetate succinate (HPMCAS) for delayed-release applications.

  • Enteric coatings are used for controlled-release applications.
Drug Solublization

Versatile cellulose ester used as a solid-dispersion polymer.

  • Molecules can be tailored to meet specific needs
  • Scope for API-dependent formulation flexibility
  • Economical and controllable spray-dried dispersion processes
  • Reduced risk in excipient sourcing and ease of interchangeability
  • Insoluble drug molecules interact with the hydrophobic regions; hydrophilic regions allow the formation of colloids in aqueous solution
  • Charge on the polymer minimizes the formation of large agglomerates, stabilizing drug-polymer colloids


Tablet Film Coating

Enteric film coating for tablets, capsules or granules.

  • Dissolution of HPMCAS is pH-dependent
  • Insoluble in gastric fluid but dissolves rapidly in small intestine


Document Library

Additional Information

Parameter    AquaSolve HPMCAS

LF and LG


MF and MG


HF and HG

Acetyl Content







Succinoyl Content







Methoxyl Content







Hydroxypropoxy Content







Market Information



Product Types or Functions

Controlled-release Formulations, Drug Solublization, Tablet Film Coating
Coating Polymer, Immediate-release Binder, Rheology Modifier