Product number: NCM####

GC Agar is used with lysed blood and other supplements for the isolation and cultivation of Neisseria gonorrhoeae and other fastidious organisms. GC Agar is not intended for use in the diagnosis of disease or other conditions in humans.

A nutritious agar base described by Thayer and Martin for the isolation of Neisseria gonorrhoeae. The rich peptone mixture is enhanced by the use of corn starch to absorb toxic metabolites and a buffering system is used to maintain neutral pH. The medium is made selective by the use of various antibiotic cocktails. Thayer and Martin originally recommended the use of vancomycin, colistin and nystatin and the addition of trimethoprim which is useful in preventing the swarming of proteus. More recently the emergence of vancomycin sensitive gonococci has made the selective agents (lincomycin, colistin, amphotericin, trimethoprim (X070 LCAT) the combination of choice. Enrichment of the base is usually by the addition of lysed blood. Alternatively, chocolated blood or hemoglobin powder and Thayer and Martin’s mixture of vitamins, amino acids and coenzymes can be used. GC Growth Supplement (X271) can be added to this medium to aid in the isolation of Neisseria spp.


Formula Liter
Peptone 15.0 g/L
Corn Starch 1.0 g/L
Sodium Chloride 5.0 g/L
Dipotassium Hydrogen Phosphate 4.0 g/L
Potassium Dihydrogen Phosphate 1.0 g/L
Agar 10.0 g/L

pH: 7.2 ± 0.2 at 25°C
Formula may be adjusted and/or supplemented as required to meet performance specifications.


  1. Suspend 36 grams of the medium in 1 liter of purified water.
  2. Heat with frequent agitation and boil for one minute to completely dissolve the medium.
  3. Autoclave at 121°C for 15 minutes.
  4. Cool to 45-50°C and aseptically add 5-7% of lysed blood and 2 vials of X070 supplement plus optional GC Growth Supplement X271.
  5. Mix well and dispense.

Product was previously known as Acumedia Product: 7104 GC Agar; and LabM Product: LAB067 GC Agar Base

Order Details

Product # Product Description
NCM0045A GC Agar, 500 g
NCM0045B GC Agar, 5 kg
NCM0045C GC Agar, 10 kg
NCM0045D GC Agar, 25 kg (European only size)
NCM0045E GC Agar, 50 kg (US only size)

Reference Material

NCM0045 - GC Agar, Safety Data Sheet [Danish] [Dutch] [English] [EU English] [Finnish] [French] [German] [Italian] [Spanish, Mexico] [Swedish]
NCM0045 - GC Agar, Technical Specifications Sheet [English]
7104 - GC Agar, Product Information Sheet [English] [Portuguese]

For additional information or questions about product SDS documents, please contact Neogen at

Please check with your local representative for availability of these products within your region.