Comparison of the sensitivity of 11 crosslinked hyaluronic acid gels to bovine testis hyaluronidase

Crosslinked hyaluronan gels are used in various applications where their stability is a prerequisite. The sensitivity of such gels to hyaluronidase can be determined as an index of stability by several approaches: chromatography, electrophoresis, and viscometry. We describe here a test based on the colorimetric determination of the N-acetyl-D-glucosamine released by hyaluronidase in standardized conditions. The sensitivities to bovine testicular hyaluronidase of 11 different gels used to fill skin wrinkles (Restylane; Perlane; Juvederm 18, 24, 24HV, 30, and 30HV; Surgiderm 18, 24XP, 30, and 30XP) were compared. The method was reproducible, easy to perform, not time-consuming and allowed us to demonstrate that the sensitivity to testicular hyaluronidase was dependent on the degree of crosslinking of the gels and also on their monophasic[biphasic nature. Under our conditions, Surgiderm 30, 24XP and 30XP were the most resistant gels. We propose to retain the hyaluronidase test to predict the in situ stability of a crosslinked gel used to fill skin wrinkles. (C) 2007 Elsevier Ltd. All rights reserved.