Dear colleagues, 

I think this question is more related to biochemists ans microbiologists. We would like to produce "home-made" artificial urine for investigating pathogen-pathogen relations by simulation. We have produced the artificial urine proposed by Griffith et al. containing calcium chloride - 0.46g/L, magnesium chloride hexahydrate - 0.65 g/L, sodium chloride - 4.60 g/L, sodium sulfate - 2.30 g/L, trisodium citrate dihydrate - 0.65 g/L, disodium oxalate - 0.02 g/L, potassium dihydrogen phosphate - 2.80 g/L, potassium chloride -1.60 g/L, ammonium chloride - 1.0 g/L, urea - 25.0 g/L, We decided to not adding gelatin and have added tryptic soy broth instead. It was very good for UPEC strains and for E.coli UTI89, but Lactobacilli and some other microbiota did not demonstrate a growth in this solution. We would like to perform simulation as close to nature as possible. Reason for not using human urine is attempt to avoid "individual" characteristics such as dietary habits, alcohol abuse, antibiotics etc. As well, we would like to know what may happen exactly in the urine with the exclusion of local defence mechanisms of the bladder uroepithelium. Separate uroepithelilal cell culture studies are planned to be performed later.