Comparison to existing technologies

As illustrated above, silver is selectively transferred into the microorganism until a toxic accumulation occurs. The silver accumulated in the microorganism is not toxic to other neighboring cells (or skin) because it is complexed by the proteins of the dead microorganism. The silver halide reservoir within the polymeric network replenishes the surface with silver, allowing the coating to maintain high surface toxicity to microorganisms that contact it.

Silver is not released from the coating until a germ makes contact with the surface. To the best of the Company's knowledge there are no products that offer field-applied sustained disinfectant with broad-spectrum biocidal activity. There are products such as Lysol in the liquid disinfectant category, but they lack the sustained disinfection advantages of Surfacine. Likewise, there are several controlled release technologies capable of sustained disinfection, but they lack the economics and logistical advantages of being field applied like Surfacine based products.

As illustrated above, liquid disinfectants are applied to the surface and attempt to compromise the microorganisms they contact. If they are available in sufficient quantity they kill the microorganism and might be available to damage another organism (hence their potential toxicity to humans). Depending on the type of liquid biocide, it may not kill all types of microorganisms. Likewise, microorganisms that form biofilms (such as PSA) can shield themselves from typical topical biocide applications and remain adherent to the surface. After the initial application, the biocides diffuse away or become ineffective. Thus, subsequent microorganisms that land on the surface are not affected by the previous cleaning application of the liquid disinfectant.
Typical compounds used in liquid disinfectants are Nitrogen compounds such as the benzalkonium chlorides and quaternary ammonium compounds (quats), phenols, aldehydes, iodophors, and chloroisocyanurates. Many of these compounds are corrosive and are considered toxic to humans.
In 1990, the Government Accounting Office (GAO) reported that the EPA had acknowledged that "as many as 20 percent of marketed disinfectants may be ineffective." These problems may result from incorrect formulation, incorrect or infrequent application, lack of sufficient contact time, or compound ineffectiveness against a particular pathogen.

Surfacine has the following advantages compared to liquid disinfectants:

• It continues to be highly biocidal long after its application to the surface;
• It has a broad-spectrum biocidal activity;
• It is not toxic, caustic or corrosive;
• It is cost competitive with several classes of existing antimicrobial compounds; and
• It does not foster the development of resistant organisms.
  

As illustrated above, these biocides are compounded during the manufacturing process into the substrate (red spheres). They diffuse out and if present in sufficient concentration may compromise some of the microorganisms in their vicinity. The material slowly exhausts its biocide reservoir and the eluted biocide concentration slowly decays to nothing. As it begins to diminish, it becomes ineffective. In order to replenish the system, the entire product must be replaced.
None of the controlled biocide release systems are currently marketed as a field applicable, sustained disinfectant. Many of these technologies would not be applicable or cost-effective for such application. In instances where the Company tested the bio-efficacy of these treated surfaces against Surfacine (e.g., MicroBan), the competing surfaces appear to be bacteriastatic (no growth) rather than bactericidal (kills the microorganisms). Most of these companies apply their technology to medical products.

Surfacine has the following advantages compared to controlled biocide release surfaces:

• It creates a broad-spectrum biocidal surface;
• It is very cost effective;
• It doesn't elute hazardous biocides;
• It doesn't just "run out" but is consumed depending upon the level of biological contamination;
• It isn't "just another silver technology" but uses silver as part of an intelligent field-applied biocide delivery system that preferentially and actively transfers silver into microorganisms;
• It can be applied to all surfaces and does not require retrofits with biocide impregnated surfaces;
• It fits into the existing familiar cleaning paradigm of applying a liquid to a surface; and
• It does not foster the development of resistant organisms.