The phrase "a certain concentration of" is correct and usable in written English.
It can be used when discussing the amount or level of a substance in a solution or mixture, often in scientific or technical contexts.
Example: "The experiment required a certain concentration of salt in the solution to achieve accurate results."
Alternatives: "a specific level of" or "a particular amount of".
Ni foam is only reacted in a certain concentration of P containing H2O2 aqueous solution.
SmartCells' alternative is to chemically modify insulin in such a way that the active hormone is released only in the presence of a certain concentration of glucose.
Chromi": E. coli that is programmable to turn one of five colors when it detects a certain concentration of an environmental toxin.
Once a certain concentration of surfactant 4 has been reached micellar aggregates form and increase mixing between the phases, increasing the rate of reaction to form their own components.
The students added three biological parts to the Nissle bacterium: a gene that produces the lactase enzyme, a receptor that recognizes lactose, and a sensor that causes the cell to break open at a certain concentration of lactose.
Above a certain concentration, of the order of 1 wt%, the absolute value of the ζ-potential reaches a saturation plateau.
It was found that the MPOF probe only have a response to nitrites in a certain concentration of sulfuric acid solution.
When hydrogen bonds can be formed between cyclodextrins, the filling ratio drastically increases at a certain concentration of the cyclodextrins, and inclusion complexes are formed.
Moreover, Zn doped CaSiO3 prepared by adding a certain concentration of zinc nitrate into the soaking system exhibited higher chemical stability and enhanced antibacterial activity.
Anisotropic two-dimensional scattering pattern due to shish-like structure formation was observed above a certain concentration of the high molecular weight PE.
However, when put a certain concentration of GSH into this system, the fluorescence sensor was turned to the "on" state, which was related to a competitive affinity of Hg2+ to GSH and the N atoms of porphyrin ring.
