The Neutral Self-Assembling Peptide Hydrogel SPG-178 as a Topical Hemostatic Agent

Abstract

Conventional self-assembling peptide hydrogels are effective as topical hemostatic agents. However, there is a possibility to harm living tissues due to their low pH. The aim of the present study was to demonstrate the efficacy of SPG-178, a neutral self-assembling peptide hydrogel, as a topical hemostatic agent. First, we measured the bleeding duration of incisions made on rat livers after application of SPG-178 (1.0% w/v), SPG-178 (1.5% w/v), RADA16 (1.0% w/v), and saline (n = 12/group). Second, we observed the bleeding surfaces by transmission electron microscopy immediately after hemostasis. Third, we measured the elastic and viscous responses (G′ and G″, respectively) of the hydrogels using a rheometer. Our results showed that bleeding duration was significantly shorter in the SPG-178 group than in the RADA16 group and that there were no significant differences in transmission electron microscopy findings between the groups. The greater the G′ value of a hydrogel, the shorter was the bleeding duration. We concluded that SPG-178 is more effective and has several advantages: it is non-biological, transparent, nonadherent, and neutral and can be sterilized by autoclaving.

Structure–mechanical property correlations of hydrogel forming β-sheet peptides

“…Interestingly, after heating (30 min at 75 1C) DAR16-IV turns into a stable a-helix structure that fails to give hydrogels and slowly returns to a b-sheet assembly. 139 A closely related peptide Ac-RLDLRLALRLDLR-NH 2 (SPG-178), with an isoelectric point of 11.5, is more soluble and its hydrogel is stable at physiological pH. 65 2.3.5 The peptide charge.…”

“…In this case, a-helix formation could be attributed to the presence of negatively charged residues (Asp) close to the N-terminus and positively charged (Arg) residues near the C-terminus as discussed earlier. 139 SPG-178 forms stiffer hydrogels than RADA16-1 ( Table 2). One can infer that the overall peptide charge will also have an important effect on the properties of a peptide hydrogel.…”

Nanofibrous Snake Venom Hemostat

“…Importantly, under intermittent high shear rates, peptide hydrogels recover to preshear G′ values within 60 s. Together these results suggest the ability to use a material, which is easily injectable, and that can reself-assemble to form a strong conformal gel, presenting a physical barrier to bleeding. 6–8,51 …”

Hierarchical Structure of the Fibrillar Hydrogel Network of a Self‐Assembled Synthetic Peptide Revealed by X‐ray Scattering and Atmospheric Scanning Electron Microscopy

“…The use of synthetic peptide hydrogels may minimize the risk of biological contamination. Previous studies examined synthetic self-assembling peptide-based gels [5,[6][7][8][9] and their applications, such as 3D cell culture scaffolds, [10][11][12][13] hemostats, [14,15] lubricants for osteoarthritis, [16] regenerative medicine, [17] wound healing, [18] and drug delivery systems. [19,20] The efficacy of these self-assembled materials may be affected by various factors, including pH, temperature, and the concentrations of salt and peptides.…”