Penicillin G Benzathine

Benzathine Benzylpenicillin1.0 % lec., 0.2 % Tween, microfine, sterile

Molecular formula:
2(C16H18N2O4S).C16H20N2.4H2O
Molecular weight:
981.2
CAS registry no.:
41372-02-5
 Benzathine

Application

Mainly used in the manufacture of ready-for-use aqueous suspensions for injection. It must be suspended in water for injection using an agitator. The result is a homogeneous, agglomerate-free suspension, which shows an excellent physical stability due to the optimized particle size of the material. In order to improve the wettability and suspendibility the material is coated with 1.0 % of lecithin and 0.2 % of Tween.

Antibiotic category

Depot penicillin for long-acting blood levels

Packaging

Storage

Store below 25°C,
Protect from light and moisture

Shelf life

60 months

Specification

Appearancewhite to whitish, crystalline powder
Particle sizex(50,3): 4 - 10 µm
80 %: 2 - 20 µm
exceeding 50 µm:
informative
exceeding 125 µm:
informative
Acidity or alkalinitycorresponding to BP/Ph.Eur.
Water content
(Karl Fischer)		5.0 – 8.0 %
pH-value4.0 – 6.5
Sterility
(USP/Ph.Eur.)		sterile
Bacterial endotoxins
(LAL-test/USP)		not more than 0.010 EU/100 IU
Largest impurity
(Ph.Eur./HPLC)		not more than 1.0 %
Benzylpenicilloic acid benzathide
(Ph.Eur./HPLC)		not more than 2.0 %
Assay/Content
  • Penicillin G Benzathine (HPLC):
    96.0 - 102.0 % 1)
  • Penicillin G (HPLC):
    61.4 - 71.6 %
    65.0 - 76.0 % 1)
  • Benzathine (HPLC):
    24.0 - 27.0 % 1)
  • Lecithin (HPTLC):
    0.5 - 1.5 %
  • Polysorbate (HPTLC):
    0.1 - 0.3 %
1) Based on the anhydrous and non-coated substance

Pharmacopoeial quality

The active substance corresponds to USP, BP, Ph.Eur.