A process for preparing parenteral iron-saccharidic complexes, and the complexes produced, comprising: (1) providing an aqueous solution or dispersion including (i) Fe(III) and (OH)&minus； ions and (ii) at least one saccharide, to form a reaction mixture, where the molar ratio of (i): (ii) is about 30:1 to about 1:30； and the mixture temperature and pH are at or above the complex assembly point (CAP)； and (2) maintaining temperature and pH at or above the CAP for a time sufficient to form an iron-saccharidic complex having a molecular weight of about 25,000 Daltons or more. Control of the temperature and pH efficiently produces a high molecular weight complex. The complex can be separated by precipitation, dialysis and/or column fractionation and, if desired, dried, e.g., lyophilized or spray dried. The process can controllably synthesize complexes of varying molecular weight and/or chemical composition, particularly sodium ferric gluconate and ferric hydroxide-sucrose.
