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Numerous publications focus on the pH values and the function of the pH in the environment and in different organs of the human body. However, it is equally important that each biological system possesses a widely unrecognized buffer system to maintain that specific pH. By definition, a buffer system is a solution that resists a change in pH when acids or bases are added. In many ways, our lives are dependent on the functioning of buffer systems.

Buffer capacity means the amount of H⁺/oxonium or hydroxid ions that is needed until the pH value of a solution changes by the unit 1. Buffers are solutions containing a weak or medium strong acid (base) and the salt of the corresponding base (acid) in about similar concentrations. Both parts of the buffer mixed equally (in the ratio 1:1) results in an optimal buffering capacity. Variations of this relationship are possible. However, the buffering effect will be reduced, if the pK_a ±1 value will be left. According to Henderson-Hasselbalch-Equation: pH = pKs + lg (c[A−]/c[HA]), the relation should be not less than 10:1 or 1:10, due to dramatically reduced buffer capacity.