The National Institute of Standards and Technology (NIST) plans to negotiate a sole source procurement with Starna Cells for Fluorescent Phosphate Optical Glass Units under the authority of FAR 13.106-1(b)(1). This acquisition supports the NIST Biosystems and Biomaterials Division's need for copper-containing phosphate glass units to create the NIST Standard Reference Material SRM 2943a, critical for fluorescence spectroscopy measurements. Starna Cells is uniquely qualified, having over 40 years of history supplying similar materials, and is the only U.S. small business capable of this specialized glass production. The order will be a Firm-Fixed Price purchase under NAICS code 327212. No competitive solicited quotations will be sought, but interested parties may submit their capabilities by July 28, 2025, for government consideration. The document serves as a presolicitation notice, highlighting the specialized nature of the required products and reinforcing the government’s justification for a sole source procurement.