NANOFLEX AND STABINO

The United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), Wildlife Services, Fort Collins, CO, intends to issue a sole source purchase order with Microtrac for one Microtrac NanoFlex with external probe and one Stabino particle charge titration analyzer. The Nano-Plex particle size analyzer is the only instrument which provides the following features in a single unit: 1. Heterodyne dynamic light scattering (DLS) technology to permit analysis of sub-nanometer particles with no matrix interference. 2. Small volume sample analysis using an external probe, not a cuvette, resulting in no destruction/loss of sample 3. Analysis of sample concentrations up to 40 percent by volume without dilution allows little or no sample preparation prior to analysis to reduce dilution errors and speed sample throughput. The Particle Charge Titration Analyzer is the only instrument that provides the following in a single unit: 1. mechanically-driven titration measurement system rather than electrophoretic or DLS systems for zeta potential/streaming potential determination for faster, more accurate and stable measurements 2. Two titration pumps to permit fast (<5 min) titrations, and allowing both pH and electrolyte titrations. Unit also permits forward/backward titration for greater accuracy. 3. Analysis of high sample concentrations, up to 40 percent, by volume with no sample dilution requirement which reduces sample preparation time and eliminates dilution errors. 4. Analysis of sample particle sizes up to 300 um without the necessity for dynamic light scattering. 5. Small, 5 ml - 10 ml, sample requirement, allowing analysis of small research-scale solutions. The proposed contract action is for supplies for which the Government intends to solicit and negotiate with only one source under the authority of FAR 6.302. This notice of intent is not a request for competitive proposals. A determination by the Government not to compete with this proposed contract based upon responses to this notice is solely within the discretion of the Government.