Molecular weight determination of hypromellose phthalate (HPMCP) using size exclusion chromatography with a multi-angle laser light scattering detector.
The molecular weight of hypromellose phthalate (HPMCP), a polymer used for enteric coating, was determined using size exclusion chromatography with a multi-angle laser light scattering detector. The values of weight-average molecular weight (Mw) of commercially available grades (HP-55, HP-55S, and HP-50) were 45600, 60200, and 37900, respectively. Their inter-day precisions expressed in terms of the coefficient of variation were less than 3%. A correlation curve between Mw and solution viscosity was prepared so that Mw could be easily estimated from the solution viscosity measured by the compendial method.
Shin-Etsu Chemical Co. Ltd., Specialty Chemicals Research Center, Kibiki-mura, Nakakubiki-gun, Niigata, Japan.
Miyuki
M
Fukasawa
Sakaé
S
Obara
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002850:Chromatography, Gel; D005079:Excipients / Q000737:chemistry; D007834:Lasers; D008747:Methylcellulose / Q000031:analogs & derivatives* / Q000737:chemistry*; D008970:Molecular Weight; D012542:Scattering, Radiation; D014783:Viscosity
D005079:Excipients; D008747:Methylcellulose; C053309:hydroxypropyl methylcellulose phthalate