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Basic Requirement:

The particle sizer required must be a laboratory grade instrument used for the measurement of size, molecular weight, mobility and zeta potential of dispersed particles and molecules in solution. The instrument must be capable of measuring particles ranging in size from 0.3 nm to 10 microns. It must cover a range of molecular weights spanning 980 Daltons to 2x107 Daltons. It must be able to measure Zeta potentials across a range > +/- 500mV and a mobility range >+/- 20μ.cm/V.s. The systems optical bench must include a Helium Neon laser (633nm, max 4mW) with an APD detector.

Additional Requirements:

Instrument must use 120V/60 Hz US standard power.

Instrument controller and analysis software must come loaded on a desktop computer with color display monitor running Windows 10 operating system also 120v/60Hz. Software must include concentration calculator and provide for linking to standard operating procedures for creating custom automated measurement sequences.

Must have non�invasive back scattering technology.

The position of the sampling volume within the measurement cell must be variable, either by automatic or manual control, to minimize signal interference and measure the sample with minimal or no dilution required.

Must be capable of optimal positioning by brief measurements and analyses of correlation at varying depths of focus.

Zeta potential measurement must be by diffusion barrier technique allowing for measurement of minimal sample quantities (approx. 30 microliters).

Must be equipped with a folded capillary cell which enables size measurement before and after zeta potential determination without transferring the sample between cuvettes or measurement cells.

Must come with components necessary for performing surface potential measurements.

Must be capable of Mixed Mode Measurement Phase Analysis Light Scattering for the measurement of zeta potential and protein mobility. Must be capable of testing low mobility samples by combining fast field and slow field reversal.

Must come equipped an autosampler to accommodate up to 96 sample vials to accurately deliver each sample into the analyzer for automated particle or molecular size measurements.

Must have the ability to measure in a continuous flow mode with a size range from 0.6nm to 6 microns during flow measurement.