|
Dressing Studies  Better technology. Better outcomes.™ |
Advanced Antimicrobial Wound,Burn, and Surgical Care Products |
| View: | Wound Dressings | Burn Dressings | Surgical Dressings | Silverlon Home Page |
|
Dressing Studies Better technology. Better outcomes.™ |
Advanced Antimicrobial Wound, Burn, and Surgical Care Products |
Silverlon® Biocompatibility Studies
The Silverlon® fabric was
tested by the ISO Sensitization Study in the Guinea Pig (Maximization
Method of Magnusson and Kligman, 1970) to evaluate the potential for delayed
dermal contact sensitization. Studies
were performed by North American Science Association Inc.
Method
The Silverlon® material was extracted in 0.9% sodium chloride and cottonseed oil and intradermally injected and occlusively patched
to ten test guinea pigs (per extract) in an attempt to induce sensitization.
Silverlon® was similarly injected
and occlusively patched to five control guinea pigs.
Following a recovery period, the test and control animals received
a challenge patch of the appropriate Silverlon® extract and the reagent
control. In addition the
test article was applied to the same animal.
All sites were scored at 24, 48, and 72 hours after patch removal.
Results
Silverlon® showed no evidence of causing delayed dermal
contact sensitization in the guinea pig.
Interpretation
Specific
cells (antigen-specific T cells) of the immune system react (the
reaction is called delayed type hypersensitivity) to certain materials
and substances that are foreign to the body.
Such a reaction results in what is commonly called an “allergic
reaction”. In order to determine
if a material will react and cause an allergic reaction, this study was
performed. Since there
was no evidence of delayed type hypersensitivity (delayed dermal contact
sensitization), Silverlon® can be labeled hypoallergenic.
2. Acute Intracutaneous
Reactivity Study of Silverlon®
The Silverlon® fabric was
tested by the Acute Intracutaneous Reactivity Study in the Rabbit to evaluate
the local dermal irritant effects of leachables extracted from the Silverlon®
following intracutaneous injection in rabbits.
Studies were performed by North American Science Association Inc.
Results
The objective of this study was to evaluate the cytotoxicity of
Silverlon® using an ISO elution method in L-929 mouse fibroblast cell
line in vitro based on the International Organization for Standardization
(ISO) methodology. Studies
were performed by North American Science Association Inc.
Method
The cytotoxicity was evaluated in a single strength minimum essential
medium with Earle’s Salts (MEM) supplement with 5% serum supreme and 2%
antibiotics. Based on the
USP ratio of 120 cm2 per 20 ml, a 54 cm2 portion
of Silverlon® was covered with 9 ml of MEM. Triplicate preparations were
prepared and extracted at 37oC for 24 hours. A single culture well with a confluent
L-929 mouse fibroblast monolayer was selected for each replicate and of
each extracted preparation (test, negative control, reagent control, and
positive control). Twelve
wells use used in this study. The
growth medium contained in the culture wells was discarded and the cells
washed. The medium was replaced with 2 ml of
test extract, negative control, reagent control, or positive control preparation.
All test and control wells were incubated at 37oC in
5% CO2. The cell cultures were examined microscopically
at approximately 100X magnification and evaluated using the United States
Pharmacopeia (USP) scoring guidelines. Observations were conducted for the test extract, negative,
positive, and reagent controls at 48 hours of incubation.
Results
Under the conditions of this study, the MEM test extracts showed
no evidence of causing cell lysis or toxicity.
The MEM extracts were not cytotoxic, and met the requirements of
the test. The negative controls,
reagent controls and the positive controls preformed as anticipated.
Interpretation
Silverlon® was not toxic to a line of cells called fibroblasts. One can draw conclusions from this that
Silverlon® is not toxic to cells in open wounds.
The objective of this study
was to evaluate the presence of any leachable chemicals from Silverlon®
that would cause in vitro red blood cell hemolysis. Studies were performed
by North American Science Association Inc.
Method
Silverlon® was prepared in duplicate and extracted in 0.9% sodium
chloride USP solution at 700C for 24 hours. Blood was obtained from 3 rabbits, pooled
diluted and added to duplicate tubes of the test article extract. A negative control article extract and
USP Purified Water positive control were similarly prepared. Each tube was inverted gently to uniformly
mix the extract with the blood.
After 4 hours of incubation at 370C, the suspensions
were centrifuged and the resulting supernatant was added to Drabkin’s
reagent. The percent transmission of the
extract was spectrophotometrically measured at a wavelength of 540 nm.
Results
The negative and positive controls performed as anticipated. Under the conditions of this study,
the mean hemolytic index for the test article was 4%. The test article was slightly hemolytic.
Interpretation
Hemolysis testing of medical device materials has historically
been used to measure blood compatibility in vitro. The extract from Silverlon® caused slight hemolysis (red blood
cell death). This was not
considered significant. If
Silverlon® comes in direct contract with blood, no adverse effects are
anticipated.
The objective of this study
was to evaluate the effect of implanting Silverlon® in muscle tissue of
the rabbit. The muscle tissue
was evaluated for evidence of irritation or toxicity in accordance with
the requirements of the International Organization for Standardization
Part 6: Test for Local Effects after Implantation.
Studies were performed by
North American Science Association Inc.
Method
Rabbits were anesthetized by subcutaneous injection of butorphanol
(1mg/kg) and then sedated with acepromazine maleate (0.2 ml/kg dose). After the muscle area was wiped clean
with 70% alcohol, each paravertebral muscle was infiltrated with 1% lidocaine
to achieve local anesthesia on both sides of the vertebral column. A stylet was placed in the hub of a loaded needle. The needle was inserted into the muscle
at a 450 angle. The
needle was withdrawn over the stylet, leaving the sample in the paravertebral
muscle. Four pieces of Silverlon®
were implanted in the right paravertebral muscle of each rabbit. In the opposite muscle, four USP negative control strips
were similarly implanted. Rabbits
were observed daily for general health.
At two weeks the rabbits were euthanatized by an intravenous injection
of sodium pentobarbital based drug.
The paraveterbral muscles were dissected free and fixed in 10%
neutral buffered formalin to facilitate cutting.
After fixation, the muscles were methodically cut to locate test
and control article sites. Capsul
formation or other signs of irritation were scored and recorded.
Results
All animals
appeared clinically normal throughout the duration of the study. Body weight data for individual rabbits
were considered acceptable.
Macroscopically, there were no differences between the reactions
of the test and control materials.
This resulted in a macroscpoic reaction of “Not significant” tissue
contact irritation. Under the condition of this study, the macroscopic
reaction was not significant as compared to the USP negative control implant
material. Microscopically, the reaction was a slight irritant as compared
to the USP negative control implant material.
Interpretation
Silverlon® fabric, when implanted into a muscle, is safe with
very little tissue reactivity.
The objective of this study
was to evaluate the acute systemic toxicity following injection of an
extract of Silverlon® fabric extracted in an aqueous and an oil solvent. These extracts were evaluated for systemic
toxicity in accordance with the requirements of the International Organization:
Biological Evaluation of Medical Devices, Part 11: Test for Systemic Toxicity.
Studies were preformed by North American Science Association Inc.
Method
The aqueous vehicle was 0.9% sodium chloride and the oil vehicle
was cottonseed oil. A ratio
of 120cm2:20 ml (surface area of test article to volume of
vehicle) was used for each preparation.
The test article was extracted in the aqueous and oil solvents
at 700C for 24 hours. The extraction vehicles without test
articles were similarly prepared to serve as reagent controls. Five mice (per extract) were weighed
and than each were injected with the test extract at a dose of 50ml/kg. The corresponding extraction vehicles
were similarly injected into five mice per control group. The aqueous saline was injected by the intravenous route while
the cottonseed oil was injected by the intraperitoneal route. The animals
were observed immediately and at 4, 24, 48, and 72 hours after systemic
injection.
Results
Under the conditions of this study, there was no mortality or evidence
of systemic toxicity from the aqueous or the oil extracts of Silverlon®.
Interpretation
This study revealed that aqueous and oil extracts of Silverlon® did not result in acute systemic toxic reactions.
|
For a printer friendly version of this Silverlon® Wound Dressing Biocompatibility Study Page Page, please click here |
|
|
(Toll Free) Phone: 1-888-551-0188 |
info@silverlon.com |
FAX #: 501-679-3378 |
||
|
Argentum Medical, LLC. 240 81st Street Willowbrook, Illinois 60527 |
||||
|
All of the Silverlon® Wound Care, Burn Care, and Surgical Products listed on this website are FDA Cleared. |
Silverlon® is Manufactured in the USA |
