An improved Buffer Concentrate for preparation of FeSSIF-V2

Biorelevant Media

An improved Buffer Concentrate for preparation of FeSSIF-V2 has been developed to overcome the limitations of the previous maleic acid buffer system. It has similar properties but enables easier medium preparation with better chemical stability as well as low variability.

Composition and physico-chemical properties of FeSSIF-V2


 FeSSIF-V2 from Buffer Concentrate


 FeSSIF-V2 from scratch
Buffer Composition  Tri-Sodium citrate
Maleic acid
Citric acid
Sodium hydroxide
Sodium chloride
 Sodium chloride
Water
 Water
FeSSIF-V2 Powder Sodium taurocholate
Sodium taurocholate
Lecithin
 Lecithin
Glyceryl monooleate
 Glyceryl monooleate
Sodium oleate
 Sodium oleate

Properties
Appearance  Colourless, slightly opalescent
 Colourless, slightly opalescent
pH (at 37°C)
 5.80 ± 0.05
 5.80 ± 0.05
Surface tension (mN/m)
 34
 34
Buffer capacity (mM/L/ΔpH)
 21
 25
Osmolarity (Osm/L)
 0.387
 0.388

Media preparation

FeSSIF-V2 has been prepared in two ways using FeSSIF-V2 Powder (V2FES) with

1) diluted Biorelevant FeSSIF-V2 Buffer Concentrate (VFESBUF), and

2) original buffer prepared from scratch.

The physico-chemical properties of both media have been tested for 48h and are presented in the Table below.

Comparison Table


 FeSSIF-V2 from Buffer Concentrate  FeSSIF-V2 from scratch
Easy to prepare ✓
 X
Quick preparation ✓
 X
pH adjustment not needed ✓
 X
Number of required components 3 5
Inter and intra lab reproducibility  ✓
 X

Physical parameters after preparation

FeSSIF-V2 prepared using FeSSIF-V2 Powder with corresponding diluted Buffer Concentrate and FeSSIF-V2 prepared using FeSSIF-V2 Powder with buffer from scratch have very similar physico-chemical properties (pH, surface tension and buffer capacity). These properties remain stable for at least 48h. FeSSIF-V2 made using FeSSIF-V2 Powder and diluted FeSSIF-V2 Buffer Concentrate is an easy, efficient and reliable preparation method.