USP <660> Glass Containers

The United States Pharmacopeia (USP) enforces rigorous testing requirements for containers and their closure system as they must not interact physically or chemically with the drug product in any way that would alter its quality or efficacy. General Chapter <660> outlines specific qualification tests based on the type of glass used for containers that come into direct contact with the pharmaceutical formulation. At a macro level, the physicochemical quality of the glass container is defined by measuring their hydrolytic resistance, or resistance to chemical attacks. To define a test program that meets regulatory standards, you must understand and determine the type of class being used.

  • Type I Glass: Borosilicate glass that contains significant amounts of boric oxide, aluminum oxide, and alkali and/or alkaline earth oxides, it has a high hydrolytic resistance and a high thermal shock resistance due to the chemical composition of the glass itself.
  • Type II Glass: soda lime glass that that has a suitable treatment of the inner surface such that it will raise the hydrolytic resistance from a moderate to a high level.
  • Type III Glass: soda lime silica glass contains alkaline metal oxides, mainly sodium oxide, and alkaline earth oxides. It has a moderate hydrolytic resistance due to the chemical composition of the glass itself.

Other critical factors in determining an ideal test plan include the volume of the glass container and the use of a colorant. Glass that is colored (amber) and intended to offer protection from light, will be subject to USP Spectral / Light Transmission testing referenced in USP <671>. Once the critical factors are determined, a test plan can be developed that can include the following test methods:

  • Glass Grains Test
  • Surface Glass Test
  • Surface Etching Test
  • Hydrolytic Resistance Determination
  • Determination of Type I / Type II
  • Light Transmission if Applicable

CS Analytical has the knowledge, experience and laboratory instrumentation to assist with all your USP <660> Glass Testing requirements in a cGMP, FDA regulated setting.