Development of New Hplc Method and Identification and Quantification of Nalidixic Acid, Ciprofloxacin in Fish Tissue.

Nalidixic acid is the first of the synthetic quinolone antibiotics. In the technical sense, it is a naphthyridone, not a quinolone: its ring
structure is a 1,8-naphthyridines nucleus that contains two nitrogen atoms, unlike quinoline, which has a single nitrogen
atom.[1]Synthetic quinolone antibiotics were discovered by George Lesher and coworkers as a byproduct of chloroquine manufacture
in the 1960s.[1] Nalidixic acid is effective against both gram-positive and gram-negative bacteria. In lower concentrations, it acts in
a bacteriostatic manner; that is, it inhibits growth and reproduction. In higher concentrations, it is bactericidal, meaning that it kills
bacteria instead of merely inhibiting their growth.