Gelatin for Hemostatic Pad and Sponge

Selecting the Ideal Gelatin for Hemostatic Pad and Sponge Production

In the manufacture of absorbable hemostatic pads, gelatin acts as a mechanical matrix that promotes platelet aggregation and provides a physical framework for clot formation. Given its role in surgical and trauma care, the selection criteria for gelatin shift from functional rheology to biomedical safety and microstructure-forming capabilities.

1. Medical and Pharmaceutical Grade Compliance

Hemostatic pads are often intended for internal use or deep wound care. Therefore, the gelatin must meet the highest purity standards.

·         Standards: It must comply with USP (U.S. Pharmacopeia) or EP (European Pharmacopoeia) monographs for "Gelatin, Absorbable."

·         Safety: The gelatin must be BSE/TSE-free and sourced from animals raised under strictly controlled conditions with full traceability.

2. High Bloom Strength for Structural Integrity

To create a "sponge" or "foam" structure through lyophilization (freeze-drying), the gelatin must have a robust molecular network.

·         Range: Typically, a High Bloom (250–300) is preferred.

·         Reasoning: High-bloom gelatin provides the mechanical strength required for the pad to stay intact when saturated with blood. It prevents the sponge from dissolving too quickly or collapsing upon contact with fluids.

3. Low Endotoxin Levels

For any product that comes into contact with the bloodstream or internal tissues, endotoxin control is critical.

·         Threshold: High-quality medical gelatin should have endotoxin levels below 10 EU/g (some premium grades are < 2 EU/g).

·         Impact: Low endotoxin levels minimize the risk of pyrogenic (fever-inducing) reactions and post-operative inflammation.

4. Solubility and Setting Temperature

The preparation of the gelatin "foam" before freeze-drying requires precise temperature control.

·         Setting Speed: The gelatin must have a consistent setting point to ensure a uniform pore size during the freezing process.

·         Porosity: The pore size determines the capillary action of the pad. A gelatin that forms a stable, homogenous gel allows for the creation of an interconnected porous structure, which is essential for rapid blood absorption.

5. Biodegradability and Cross-linking Potential

Hemostatic pads must be absorbed by the body without causing a foreign-body reaction.

·         Control: Manufacturers often use cross-linking agents (like Glutaraldehyde or Heat Treatment) to adjust the degradation time.

·         Selection Tip: The gelatin must have a consistent concentration of amino groups (specifically Lysine) to allow for predictable cross-linking, ensuring the pad stays in the body for the required duration (usually 2–4 weeks) before being fully resorbed.

6. Neutral pH and Biocompatibility

The gelatin must maintain a neutral pH (5.5–7.0) to avoid tissue irritation and ensure compatibility with added active ingredients, such as Thrombin or Calcium, which are often impregnated into the pad to accelerate clotting.

Conclusion

The selection of gelatin for hemostatic pads is driven by clinical safety and structural performance. By prioritizing high-bloom, low-endotoxin pharmaceutical grades with consistent cross-linking characteristics, manufacturers can produce hemostatic sponges that are both highly effective in hemorrhage control and safe for patient internal use.