Hawkeye-Jensen, Inc.  
4408-B Pottsville Pike  
Reading, Pennsylvania 19605  
(610) 921-5955
1ppm Silver Water® solution
3ppm Silver Water® solution
20ppm Silver Water® solution
1.0% Germaben II solution

24-hour reduction test

Esherichia Coli                             ATCC 13047
Pseudomonas Aeruginose        ATCC 27853
Staphylococcus Aurous           ATCC 6538
Candida Albicans                      ATCC 14053
Aspergillus niger                       ATCC 16404

To determine if any of the above test samples has the ability to be substantially detrimental to a significant population of known organisms.

Twenty milliliters (ml) of sample were transferred to each of five sterile, capped sample cups. Each cup was inoculated with a calculated inoculum of approximately 1 x 10 of each of the given microbial suspensions and mixed. Samples were taken and plated at 24 hours after inoculation.


3ppm 10ppm   20ppm 1.0% Germaben II
E.Coli  130  <10 50 <10
Aeruginosa 50 <10 10 <10
Staph.Aureus 4,000 750 370 2,000
C.Albicans 50  80  70 <10



The results show and compare how much each test organism was reduced in each product (3,10, 20 and 1.0%) in a 24-hour period.

Starting with approximately a 750,000 population of each organism, the 3ppm reduced the E.Coli 130 times, the l0ppm less than ten times, the 20ppm 50 times and the 1.0% Germaben II less than 10.

                               Test Organisms:

Group Organisms Used
Ferm. Gram-neg  Enterbacter Cloacae
Eacherichia Coli
ATCC 13047
Non-form.Gram-negs Pseudomonas Aeruginosa
Burkholderia Cepacia
ATCC 27853
Gram Pos. Cocci Staphylococcus Aureus  ATCC 6538
Yeasts  Candida Albicans  ATCC 14053
Molds Aspergillus Niger ATCC 18404


                               Culture Maintenance:

Culture Maintenance Agar Storage  Transfer Options 
Bacteria Trypticase Soy Refrigeration Monthly
Yeasts Bactrol Disks Refrigeration As needed 
Molds Sabouraud Dextrose Refrigeration Monthly



Diluents Agars
Lotheen broth Lotheen agar (bacteria, yeasts)
Sabouraud Dextrose (molds)


                             Inoculum Preps:

Culture  Incubation
 Bactaris 30-35 C/24-48 hrs.
 Yeasts same
Molds 20-25 C/7-14 days


1. At least 20 g of product is inoculated with microbial suspension, so as to give 10 bacteria or 10 yeasts or molds per gram of product.

2. Using minimum sample size of 1 g. prepare decimal dilutions, and determine plate count/g of sample, by pour or surface plating methods.

3. Read plates after 2-3 days @ 30-35 C (bacteria/yeasts), and 3-7 days @ 20-25 C (molds).

4. Resample @ 1,2,3,7,14,28 days at ambient temp.

5. Rechallenge if specified.


At least 99.9% reduction (veg. Bacteria)/90.0% reduction (molds) within 7 days. Ref: CTFA 1993 Sect. 13 pp 1-2

Challenge testing for the Burn Cream with Colloidal silver was begun on 10/22/97 for the yeast and bacteria groups (excluding Gram positive, which has not been started). And 10/30/97 for the mold group.

The yeast on bacteria groups were reduced 99.99% by day 1 and continued through day 7. The mold had a lesser percent reduction on day one however further testing must be done to make substantial claim.