Aerosol Particle Collector

What it does:

The Spot Sampler captures fine and ultrafine particles in a concentrated manner for easy, off-line analysis.  Its moderated condensational technology enlarges particles without temperature extremes, making it ideal for volatile or biological applications.  


  • Centerline saturation ratios reach 1.4 while maintaining temperatures below 25°C.

  • Dry sample deposits measure just over 1 mm in diameter.

  • High collection efficiency down to <8nm, with no particle bounce

How It Works:

Aerosol is sampled through a wet walled tube, the middle section of which is warm

  1. In the first, Conditioner section, the flow is cooled and humidified.

  2. In the warm-walled Initiator section, water evaporates from the wet walls faster than the flow warms. The flow becomes supersaturated, initiating the condensational growth of particles >5nm.

  3. In the final, Moderator section, heat and water vapor are removed from the flow while maintaining supersaturated conditions that allow continued growth to form ~3µm droplets.

  4. The droplets are collected by impaction, and warmed to make a concentrated, dry spot. Collection into liquid is also possible.

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Extraction by the autosampler

Extraction by the autosampler

Samples are collected as a sequence of ~1-mm diameter dry spots on a multiwall plate. Upon return to the laboratory, the plate is placed on an auto-sampler which handles all the sample extraction and HPLC or IC injection. Concentrated spots are also amenable to many analytical approaches, such as nano-DESI and LIBS, etc.

Dotted lines are for high particle concentration.

Dotted lines are for high particle concentration.

Collection efficiency

Collection efficiency

Twice-daily nitrate, sulfate and PAHs in Stockton, CA

Twice-daily nitrate, sulfate and PAHs in Stockton, CA


The Spot Sampler is sold through Aerosol Devices Inc.