Variable-Rate Flask Shakers

Wrist-Action Flask Shaker Photo

St. John Associates' variable-rate flask shakers are solidly built, continuous-duty devices designed for the agitation of solid phase peptide synthesis flasks and other similar glassware. Models are available with 120-, 180- and 360-degrees of arc for use with both sealed and stoppered glassware. All shaker models come with a standard, three jaw laboratory clamp as shown and conversion for use with 230VAC 50Hz (Euro) power is optional.

Available shaker models include:

  • 120-Degree Variable-Speed Flask Shaker - Part #A5-6023
  • 180-Degree Variable-Speed Flask Shaker - Part #A5-6027
  • 360-Degree Continuous- Rotation Flask Shaker - Part #A5-6028

Features | Applications | Specifications | Accessories | Download PDF Flyer

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The shaker rotates the laboratory clamp through 120, 180 or 360 degrees of arc depending on the model selected. The 120- and 180-degree models closely follow the equipment described by Merrifield and by Stewart in their numerous publications on peptide synthesis.

Peptide synthesis glassware ranging in size from small (0.1 to 1.0 gm) to large (5 to 10 gms) capacity is handled with ease. Heavy aluminum construction prevents “walking” of the shaker on the benchtop. Conservative motor rating assures cool operation. Shaft bearing design permits operation in the cold room if desired.

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St. John Associates' shakers are suited to just about any application where thorough, gentle agitation is indicated. The following list highlights the most popular applications for our shakers:

  • Peptide synthesis
  • Dissolution of solids
  • Culture flask agitation
  • Viscous polymer mixing

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  • Power Requirements: 115 VAC, 50/60 Hz (USA) or 230 VAC, 50/60 Hz (Euro)
  • Weight: Approximately 14 lbs
  • Size (clearance): 6" W x 9" H x 11" D
  • Clamp Shaft Size: Up to 13mm dia.

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Accessories and Parts

St. John Associates offers a number of accessories for our line of flask shakers. These accessories include clamps which allow you to shake multiple samples as well as maintenance and replacement parts. Click here for our list of shaker parts and accessories.