What's New

CatalogueNew Instrument, MicroBrook 2000LD
New instrument for broad range particle size.

New Particle Solutions version 3.0!

New protein and polymer calculator.

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New NanoBrook Series!

Brookhaven is proud to announce its newest addition: the NanoBrook series, featuring the NanoBrook Omni. Now with backscattering for proteins, peptides, mAb, RNA and other biological samples.

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New gold nanoparticles app note!

How Many Au Nanoparticles Does It Take to Circle the Earth?

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New BSA app note!

Absolute Size Exclusion Chromatography of BSA

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New services available from Brookhaven Instruments!

Learn how Brookhaven can assist in material characterization and training courses.

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PEGSMeasure size and surface charge of exosomes, microvesicles and liposomes
App note (pdf)

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Broad Spectral and Dynamic Range

  • Overview
  • Typical Applications
  • Specifications
  • Options & Accessories

Features at a glance

  • Powerful in red, green and blue wavelengths
  • Perfect for 10 nm to 6 µm particles
  • Colloids

Measure Sub-Micron Particles with a Brookhaven PMT Detector

A Photomultiplier Tube (PMT) is the detector-of-choice for weak light detection. It has a virtually noise-free internal photoelectric gain in excess of 106 with a bandwidth greater than 1 GHz. This renders a PMT with a very wide detection dynamic range. It can be operated at light level as low as a few photons per second or as high as a billion photons per second. By properly choosing the photocathode materials, its radiant sensitivity can be tuned for any visible light.

Brookhaven’s standard light scattering detector, BI-PMT, operates in photo-counting mode and features a multialkali photocathode with detection sensitivity optimized for all wavelengths commonly used in light scattering instruments, namely 633nm, 514nm and 488nm (see the inserted spectral response). Its broad detection dynamic range (~ 105) guarantees the excellent performance for particles with sizes from a few nanometers to microns, in terms of both particle sizing and zeta potential measurements. This versatility can be demonstrated with the measurements of liposome.

broad spectrum BI-PMT

Measurements with Liposome

Liposome is a lipid bilayer vesicle composed of natural phospholipids. It serves as deliver vehicles of nutrients, drugs and DNA in biological systems. For optimized loading of viable contents and specifically targeted delivery, its size, surface charge and other characteristics are usually engineered over a wide range via novel formulations and deliberated manufacture processes. Therefore, it is important to monitor the size and ζ potential of liposomes in a rapid and non-invasive way. Brookhaven DLS and ELS/PALS instruments equipped with a BI-PMT detector offer a valid solution for the purpose. In the measurement below, DLS measurement reveals a relatively broad size distribution,with an effective diameter of 200.07 nm, in this particular liposome formulation and sample preparation process.



Summary Report of Measurement of Liposomal Formulation

Utilizing Brookhaven PMT Detector (click to enlarge)


Brookhaven also offers two advanced detector options dedicated for small weak scatters with size typically below 10nm. One is the BI-CrossCOR, a dual-PMT detector, which improve the correlation data quality at short delay time by eliminating the afterpulsing peak. Another option is the BI-APD with 10 times higher detection sensitivity due to the high quantum efficiency of an avalanche photodiode.


Typical Applications

Measurements of sub-micron particles between 10 nm and 6 µm.

Strong sensitivity in red, green and blue laser wavelengths


Detector: Broad sensitivity, photomultiplier tube

The BI-PMT is also available for use with the BI-200SM. The BI-200SM is capable of interchangeable detectors. Please contact factory for details.

A policy of continual improvement may lead to specification changes.

Options and Accessories

BI-SCP: Box of 50 plastic cells/tops.