What is 1:10 dilution exactly?

10g of sample dissolved in 100ml of diluent or 90ml of diluent? which one is correct as per regulatory guidelines.

1:10 dilution is 10gm -> 90 ml means dissolve 10 ml and make it up to 100 ml.

its not clear. we used to prepare 90ml SCDM or 100ml SCDM only. so supposed to dissolve 10g in 90ml or 100ml of diluent. bt after dissolving how to make up in case of solids?.

in case of liquids whatever u said its right, we can directly 10ml of sample dissolved in 90ml, it is 1:10. but in case of solids how to make up?

You are right in case of strile media it is not possible to make up 100 after addition of solid sample therefore, we add 10gm sample in 90ml SCDM.

Thank you very much sir,