What Is PluroGel®

Why PluroGel® Is Beneficial In All Phases Of The Would Healing Cycle

PluroGel® is utilized in burn and wound care and was developed in the plastic surgery department at the University of Virginia. PluroGel® properties are beneficial for and can be used in all stages of wound care. PluroGel® based Products have been used on over 14,000 patients to date. PluroGel® is approved for sale outside the USA as PluroGel® PSSD (single antibiotic) and PluroGel® Burn and Wound Dressing (no antibiotic). The Company is currently in Phase II Clinical Trials for PluroGel® PN (double antibiotic) to treat infection in diabetic ulcers, with support from the DoD Wounded Warrior Program.

PluroGel® is comprised of FDA approved ‘Generally Recognized As Safe’ (GRAS) substances. Its surfactant-based poly-mer component (a polymer is a molecule with repeating sections) has been in routine use for many years in products for medical devices and drugs. PluroGel’s surfactant-based polymer biomaterial is built with two polymer chains, one being hydrophilic or ‘water-loving’ and one being hydrophobic or ‘oil-loving’. When conditions are appropriate, this polymer forms sphere-like micelles (Diagram 1) named PluroGel® Micelles (PluroGen’s exclusive and patented know-how) which have hydrophilic and hydrophobic components that give the PluroGel® Micelles specific steric effect (a steric effect is a spatial arrangement; For PluroGel®, the shape is spherical). This results in surfactant (detergent/cleaner) properties that, uniquely for detergents and for PluroGel®, are cell-friendly and biocompatible.1 The hydrophilic component is external on the surface of the PluroGel® Micelle sphere and the hydrophobic component is contained in the center of the PluroGel® Micelle sphere.

Through PluroGen’s exclusive and patented know-how, the PluroGel® Micelles become cross linked to form the PluroGel® MGM. To help in understanding the PluroGel® MGM, visualize a bucket of ping-pong balls (Diagram 2). These ping-pong balls represent the PluroGel® Micelles. Next, visualize the spaces between the ping-pong balls as being filled with water. This combination of the PluroGel® Micelles and water represents the PluroGel® MGM. The spaces between the PluroGel® Micelles can carry any water-soluble components; (examples can be antibiotics, antiseptics or any other material that is water soluble). The hydrophobic center of the PluroGel® Micelles can carry any oil-soluble materials; (examples can be antibiotics, antisep-tics or any other oil soluble material).

PluroGel® Products are Multi-Function with the Functions grouped into 3 categories:

  1. Core Functions: 100% water soluble for easier, faster, less painful removal; Thickens as it warms to remain on the wound; Unique biocompatible and cell friendly surfactant to support wound cleaning.
  2. Bio-Physical Functions: Maintains blood flow in the micro-vessels of the wound; Increases tissue oxygenation in the wound; Breaks up and prevents biofilm.
  3. Performance Functions: Biocompatible, cell friendly cleaner; acts as a delivery system; acts as a barrier to create the ideal wound environment for healing.

homeThe Core Functions of PluroGel® result from the PluroGel® MGM being a water-based emulsion (an emulsion is a mixture of two substances that normally cannot mix together) of the spherical PluroGel® Micelle structure with its hydrophilic (water-loving) and hydrophobic (oil loving) components. This allows wound exudate and debris to solubilize and easily rinsed off with water during dressing change, leaving a cleaner wound site13. This results in less tissue damage from the cleaning process, which aids the body’s own repair process. This attribute is significant as it allows PluroGel® dressing changes to be faster and easier with significantly reduced pain14, 15, 16 as compared to the dressing changes experienced with cream/ointment/oil based treatments, or, dressing based treatments. These other products, when mixed with the wound exudate, dry out and can require physical scraping or scrubbing and in some cases surgical intervention to remove.

PluroGel® thickens as it warms, enabling it to remain on and better protect the wound. The change from room temperature to body temperature causes the PluroGel® Micelles to be attracted more to each other than they are attracted to the water in the PluroGel® MGM. This increasing attraction between the PluroGel® Micelles results in PluroGel® thickening to stay on the wound. At a dressing change, as the temperature decreases from body temperature to room temperature, the PluroGel® Micelles are more attracted to the water in the PluroGel® MGM, resulting in PluroGel® becoming softer for easier, less painful and less damaging removal.

What-is-PluroGel

The Bio-Physical Functions of PluroGel® result in a moist, oxygenated, environment that facilitates wound healing2. Research indicates that the PluroGel® MGM may fill the breaks or “holes” created in damaged cell membranes which reduces or stops intracellular material leaking through the holes into the wound tissue3, 4, 5, 12. This filling of the holes in damaged cell membranes can aid the body in cell repair and consequently cell survival (Diagram 3).

Research further indicates that PluroGel® MGM is “squeezed out” of the cell membrane as the cell repairs the breaks in its membrane and unmetabolized PluroGel® MGM is excreted in the urine of the patient6.

PluroGel® appears to decrease inflammation associated with a wound7. One reason for reduced inflammation, in addition to the plugging of the damaged cell membrane, may be that the bradykinins released by the damaged cells become bound in the PluroGel® MGM, thus limiting the severity of the inflammatory response8. The PluroGel® surfactant action has been shown to facilitate microvascular blood flow in both arterioles and venules which otherwise in wounds can be diminished or completely blocked due to clogging from blood clotting or wound debris9,10, 11.

This apparent ability of PluroGel® to maintain blood flow10, 11 has been shown to lead to improved tissue oxygenation in wounds12, 13. Publications demonstrate that the PluroGel® MGM may have the ability to restore denatured proteins17, 18 and to enhance the delivery of selected agents into target cells by affecting the micro-viscosity of the cell membrane.19, 20, 21, 22, 23

A multitude of agents can be placed into the PluroGel® MGM. The first agents to be placed into the PluroGel® MGM have been antimicrobials and antiseptics. In PluroGen’s first product, PluroGel® PSSD, the PluroGel® MGM forms a barrier while the antimicrobial prevents microbes from growing.

A key characteristic of PluroGel® is its Bio-Physical Function of breaking up biofilm or preventing biofilm formation, which aids in wound healing. Biofilm is an oily, polysaccharide matrix that is excreted by and encapsulates the bacteria, preventing penetration by antimicrobial agents24. Biofilm is thought to physically block a wound from closing. The PluroGel® MGM surfactant (detergent) structure and properties allow PluroGel® to penetrate the biofilm capsule and disperse the biofilm25, 26. When an antimicrobial or antiseptic is present, this effect on the biofilm allows an antibiotic or antiseptic to kill the bacteria at the antimicrobial’s or antiseptic’s approved standard dose,25, 26 as opposed to published reports that antimicrobials or antiseptics must be at 4x to 1,000x stronger than their approved standard dose to kill bacteria in a biofilm27. When the biofilm encapsulation is gone and the bacteria eradicated, the wound healing process can start.

PluroGel® without antibiotic or antiseptic (PluroGel® Burn and Wound) has been found to be effective against biofilm by penetrating and dispersing the biofilm. With biofilm gone, bacteria are exposed to the body’s defenses such as antibodies and white cells, allowing the body to attempt eradication of the bacteria and begin the natural healing process.25, 26

The Performance Function begins when PluroGel® is applied to the wound. The PluroGel® MGM acts as a physical barrier to cover and protect wounds and acts as a cell friendly, biocompatible1 surfactant cleaner that facilitates wound cleaning and debridement.

PluroGel® is a Multi-Function product that is Simple to use, Flexible in its application of use, provides Cost Savings, and improves clinicians Control of patients’ compliance to follow doctors’ orders leading to improved healing.

1-27 References on file with Plurogen Theraputics, Inc. and available on request