On Biomimetics 322 study of crystallization processes, especially in biomineralization. The properties of the bioinspired synthetic polymers can be predesigned by determine the monomers sequence, resulting in the polymeric secondary structure. The feasibility to tailor polymeric properties motivated scientists to control other polymeric characteristics such as stereochemistry and chirality, mainly in order to achieve chiral recognition, and as a result, chiral separation upon crystallization.

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... Copolymers, mainly double hydrophilic block copolymers (DHBCs), are defiantly playing an important role in mimicking natural polymers. [35] [36] [37] [38] [39] [40] [41] [42] [43] [44] [45] [46] [47] [48] Copolymers or hetropolymers are polymers composed of two different monomers. The polymeric chain can have alternate ordered monomers known as alternated polymers, or two different polymeric blocks attached together, namely, a block copolymer. Block copolymers with amphyphilic properties are similar to some extent to low molecular weight surfactants. 49-50 These copolymers consist of hydrophobic and hydrophilic blocks. On the other hand, double hydrophilic block copolymers (DHBCs) have two polymeric blocks which are hydrophilic. One block is synthetically designed to have a strong specific interaction with a crystalline phase. The second block, mainly PEI (polyethyleneimine) or PEG (polyethyleneglycol), is largely responsible for the solubility and stabilization of the entire polymer in the aqueous medium. DHBCs are bio-inspired, and thus consist of blocks composed of natural building blocks such as amino acids (basic or acidic).The sequence and the number of amino acids can be controlled, and thus DHBCs have proven to be excellent model systems for the biomineralization process. DHBCs were also used for other applications such as the stabilization of nano-particles on metal species, semi-conductive materials, and as morphological modifiers. 47,51-56 The amino-acid moieties allow a fine tuning of other polymer properties, such as charge, and as a result, relative solubility by changing the pH of the solution. 57 Another important property is the possibility to control the chirality of the amino-acid moiety. The chirality of the DHBC moiety can be controlled at two different levels, the intrinsic chirality of monomers and the chirality of a secondary structure of the polymer namely, the transformation -helix and random coil by change of pH 58 and temperature. This review will mainly focus on bio-inspired chiral polymers for application of chiral recognition and chiral separation. Therefore, we will first present a short introduction to chirality with the emphasis on chirality at the solid state. We will then review the latest advances in chiral recognition and chiral separation by biomimetic soluble and insoluble chiral polymers. The chapter will also describe the use of short peptides and polysaccharides for the inhibition of water crystallization for antifreeze applications.