Sterility

All our products are supplied as "non sterile". However, most of them are sterile "de facto". Our standard methods include dissolution in organic solvents, lethal to microorganisms, and filtration thru 0.45 µm or 0.22 µm filter, prior to the final crystallization. We store the finished materials at -18^oC, a temperature unfavorable for most organisms.

Melting point

Melting point of pure organic compounds depends on many factors.

1. Generally, the purer the material, the higher the melting point. Therefore a sample exhibiting melting point lower than promised, is suspected to contain impurities.

2. Organic crystals grown in a solvent, usually capture some molecules of that solvent in their structure. The nature of the solvent alters the physical characteristics of the crystals, such as its melting point. The same compound may produce very different crystals when crystallized from Methanol of from Diethyl Ether. The melting point may differ in as much as 100^oC.

3. Such factors as the concentration of the compound, the temperature at which the crystallization has occurred, the speed of the crystallization may also lead to crystals containing 1 or two or more molecules of solvent per molecule of the compound, also leading to noticeable differences in melting point.

Solubility

All our products are subject to solubility test at room temperature, as one of the release specifications. The data published in our Certificates of Analysis are the actual test conditions. For example, if we write "Clear colorless solution at 10 mg in 1 ml of methanol", it does NOT mean that higher concentrations could not be achieved, or that the said methanol is the only solvent for that compound. What  we Do mean is that we have actually tested the said solubility and the we guarantee the compliance on the product with the specification.

The primary aim of the Solubility test is:

1. To detect impurities, insoluble at the test conditions,  that could not be detected before.

2. To detect foreign bodies, such as silica gel particles, paper fibers, charcoal particles and unspecified dust particles that might find their way into the finished product.