The unique feature of the Bubble Paddle Reservoirs is their exclusive design that eliminates "fall out zones" where particulates fall out of solution that are so prevalent with other mixing reservoirs. The Bubble Paddle Reservoirs are the only method that gives uniform suspensions of dense particulates such as Yettrium oxide SPA beads (from Amersham/GE Health Care). 

Endorsement

Here is what one of our customers at a major Pharmaceutical company had to say about our 384 Bubble Paddle Reservoir system (VP 768B & VP 755C-384B) "The reservoir is really the best thing that I have found for YSi SPA beads which immediately fall out of solution when not mixed" ..... The bubble paddle is essential for YSi beads." 

The  newest of the Bubble Paddle Reservoirs does not require a Magnetic Alligator Tumble Stirrer.  They are powered directly by small electric motors through a unique magnetic clutch system that we designed.  This magnetic clutch powers the Bubble Paddle right through the wall of the reservoir.  Just another innovation from the Engineers at V&P to facilitate your robotic or manual dispensing of cells and beads using  4,  8, 96 or 384 channel pipettor. 

We recently received a patent on both the Bubble Paddle Stirrers and the Magnetic Clutch method of powering the system  (US Patent #6,461,034) and European Patent # 1,314,471.

The advantage of the Magnetic Clutch Bubble Paddle Reservoirs over the Magnetic Alligator Tumble Bubble Paddle Reservoirs  is that they  are more economical and the drive system has a smaller footprint.   Both have the unique ability to stir suspensions even as the pipet tips remove the cells or beads from the bottom of the reservoir.  This, coupled with the very small dead volume in the bottom of the reservoir, makes this system uniquely suited to resuspending particulate specimens during the pipetting operation.  The magnetic clutch and motor are very powerful as they will stir honey at 4 degrees C.   To stir 4 or more reservoirs at the same time, we recommend you use the Tumble Bubble Paddle Reservoirs in conjunction with a  Magnetic Alligator Tumble Stirrer.  If you are only stirring 1 to 3 reservoirs, one of the Magnetic Clutch systems is right for you.

The reservoirs come standard in economical Delrin (VP 756C-1) and in autoclaveable Polypropylene (VP 756C-1P).   They can also be provided in  PTFE or coated aluminum, depending on your application.

For chemical resistance properties of Polypropylene and other commonly used plastics follow this link.

The motor in the VP 761-1 has a top RPM of 5700.  The top practical speed is ~2000 RPM.

The photos to the right demonstrate the VP 761-1 with a VP 581A mounted on the bottom which allows it to be located in a standard SBS footprint.

VP 756C-1 series Reservoir Specifications:
103 mm long, 52 mm wide and 42 mm tall
Reservoir height = 32 mm**
Reservoir volume = 50 ml
Dead volume = 1.5 ml
Cover the paddle volume = 10ml

Reservoir and VP 761-1 motor footprint:
200 mm long, 65 mm wide and 54 mm tall
 

The photo to the right illustrates our solution for long pipetting runs requiring large volumes of  suspensions.  The VP 756C-1 reservoir is simply fitted with inlet and outlet nipples connected to a large stirred reservoir via a peristaltic pump (VP 560).  In this system the Bubble Paddle reservoir never runs dry and never overflows.

The inlet and outlet nipple system comes in two types of reservoirs: Economical Delrin (not autoclavable) - VP 756C-1T and autoclaveable Polypropylene - VP 756C-1PT

VP 761M and VP 756CM-P -- Mini Bubble Paddle Stirrer

The Parylene coated mini magnetic clutch Bubble Paddle is included with the reservoir (VP 756ACMFeP).  This Paddle is also available as passivated stainless steel (VP 756ACMFe.

A 230 Volt CE compliant motor/drive version for the European market is also available (VP 761MCE).

YOx bead dispensing on to a glass plate is illustrated in the photo to the right.  The drops were made using the Innovadyne Nanodrop and the VP 761M/VP 756CM-P Bubble Paddle Stirrer to keep the beads suspended while the Nanodrop dispensed them.   Photo courtesy of Innovadyne.  Contact Innovadyne for more information.
 

VP 754CMP

Miniature polypropylene reservoir with ducted bottom for 16 pipettes including stainless steel paddle with 17 bubbles and magnetic clutch with inlet and outlet nipples,
mixes 13mL

The VP 762 incorporates a "smart" servo motor to drive the VP 756C-1 Bubble Paddle Reservoir.  This is very useful for those operations where you want to control the stirring speed and on/off functions from your robotic work station or  computer.

This motor is capable of 3500 RPM and powerful enough to convert honey into "spun honey".   The top practical speed is ~2000 RPM

Another more cost effective way to automate any of our Bubble Paddle Stirrers is to use our new Programmable Smart Switch.  Follow this link for more information.

***NEW***
VP 756CS-PTFE/VP 761S

The VP 756CS-PTFE/VP 761S is the longest Bubble Paddle stirrer (~11" long Bubble Paddle)  we have made to date.  It has 8 pick points or nodes 1.5" apart.  It holds 75 ml of solution and can stir 30 weight motor oil (420 centipoise) with ease.  It can even stir honey (10,000 centipoise) at reduced speeds.   Follow this link to more details on viscosity.

The VP 763/VP 756C-96 has been replaced by the VP 763B and VP 756C-96B which provides an even easier mounting mechanism, cooling/heating and refilling capabilities.

**Custom reservoirs with less height can easily be made to accommodate shorter pipet tips.

VP 756C-96BPTFE is the latest in our line of 96 Bubble Paddle Stirrers.  This version of the Bubble Paddle Reservoir is very useful when used in conjunction with robotic 96 well pipetting systems.  You can rest assured that all the pipet tips will contain the same number of beads or cells from the beginning of the dispensing to the end with a very low dead volume.  This stirrer is designed to be fed continuously with suspensions of beads or cells through an inlet nipple and it has a fail-safe adjustable overflow weir that is connected to an outlet nipple.   In the event that the inflow exceeds the pipeting rate the excess liquid is diverted back into the source vessel or to a waste vessel. The inlet and outlet systems can also be isolated so the system can be operated as a static reservoir.  This reservoir is also available in Delrin as the VP 756C-96B.

The VP 763B and VP 763BCE motor/gear/magnetic clutch units  reservoir/motor/gear system are plumbed to be connected to a source of heated or chilled liquid to control the temperature of the reservoir.   It replaces our VP 756C-96/VP 763 which did not have these added capabilities and features.

Reservoir Specifications:
Length = 155 mm
Width = 105 mm
Height = 40 mm
Reservoir internal height = 27 mm**
Reservoir volume = 200 ml
Dead volume = 6 ml***

Motor/Gear/Reservoir
Overall Specifications:
Length = 198 mm
Width = 158 mm
Height = 68 mm including heat sink and microplate registration feature.

**Custom reservoirs with less height can easily be made to accommodate shorter pipet tips.

*** Dead volume will vary depending on the pipet volume.

 

VP 756C-96BPTFE-FB

VP 756CP-96B / VP 756CP-96BPTFE & VP 765B

This version with 6 Bubble Paddles is similar to the 4 Bubble Paddles version above but turned 90 degrees.  It is very useful when used with both 8 tip pipettors and with robotic 96 well pipetting systems.  You can rest assured that all the pipet tips will contain the same number of beads or cells from the beginning of the dispensing to the end with a very low dead volume.  The reservoirs come standard in economical Delrin (VP 756CP-96B) and also in autoclaveable PTFE (VP 756CP-96BPTFE).


 

This reservoir/motor/gear system VP 765B is plumbed for continuous filling and overflow operation with a convenient adjustable overflow weir to control liquid height in the reservoir.  It is also plumbed to be connected to a source of heated or chilled liquid to control the temperature of the reservoir.  The overall height of the system is shorter at 56 mm.  It replaces our VP 756CP-96/VP 765 which did not have these added capabilites and was taller..

Reservoir Specifications:
145 mm long, 119 mm wide, 40 mm tall
Reservoir height = 27 mm**
Reservoir volume = 210 ml
Dead volume = 30 ml

Motor/Gear/Reservoir overall Specifications:
191 mm long, 163 mm wide, 56 mm tall including heat sink and microplate registration feature.

**Custom reservoirs with less height can easily be made to accommodate shorter pipet tips.

This version of the Bubble Paddle Reservoir is very useful when used in conjunction with robotic 384 well pipetting systems.  You can rest assured that all the pipet tips will contain the same number of beads or cells from the beginning of the dispensing to the end with a very low dead volume.  

The photo on the right illustrates the intricate ducting in the bottom of the reservoir.  This ducting design, in conjunction with the Bubble Paddle shape is key in generating the fluid movement which keeps dense particulates suspended.  A small volume of blue dye was added to the reservoir to highlight the ducting feature.
 

Our latest 384 Bubble Paddle Mixing  Reservoir was inspired by a customer that needed to chill and mix SPA beads while they were being dispensed into 384 well microplates.  They also needed to dispense large volumes so we incorporated inlet and outlet tubes with an overflow weir so SPA beads could be continuously cycled through the system with out fear they would settle out.  As deck space is always a consideration we reduced the size of the motor and overall footprint of the system (Reservoir Motor, drives and heat exchanger).   The total systems dimensions have been reduced in this new model. 

Reservoir Specifications:
147 mm long, 126 mm wide, 41 mm tall
Reservoir height = 30 mm**
Reservoir volume = 230 ml
Dead volume = 35 ml (this will depend on the sample volume withdrawn)

Total system Specifications:
191 mm long, 151 mm wide, 70 mm tall (locating feature mount) 57 mm tall (flush mount)

**Custom reservoirs with less height can easily be made to accommodate shorter pipet tips.
 

VP 768B

The photo to the right is a demonstration VP 768B made from clear polycarbonate to illustrate the internal features.  The VP 768B consists of the Motor, Drive Pulleys, Drive Magnetic Clutches, heat exchanger and a motor control.   The heat exchanger is connected to a chiller/heater bath (sold separately) to effect the desired temperature in the Bubble Paddle Mixing Reservoir.   The model on the right is constructed of a clear material to better illustrate the internal workings of the system.  The is designed to work exclusively with the VP 755C-384B.

The photo on the right illustrates the VP 768B/VP 755C-384B installed on a PerkinElmer MiniTrak using the mounting feature described below to locate the unit within an standard microplate holder on the Mini Trak.

The heat exchanger on the VP 768B can be constructed with a registration feature (same dimensions as a microplate) to facilitate locating on the robot deck or with a flush mount.
 

For robot systems that use an "ALP" to hold the microplates such as the Beckman FX, we have made a mounting system that has a pocket mount with the dimensions of a microplate and 2 thumb screws to tighten the VP 768B (with mounting feature) securely on top of the V&P ALP (FXALP-PM) .  The length of legs of the ALP will be provided per customer request.

Complete VP 768B/ VP 755C-384C Bubble Paddle plus FXALP-PM mounting system.
 

Replacement Magnetic Clutch Bubble Paddles are available in 9, 12, 13 and 25 bubble versions.  Standard material is passivated stainless steel with a conformal coating of parylene. This prevents even the most caustic reagents from attacking the paddles and releasing Fe ions into the reservoir.  We can also supply the Bubble Paddle constructed from parylene coated anodized aluminum.  Contact us about these options.

Table of Reservoir and Bubble Paddle Compatibility

* = Column format
** = Row format

VP 581A Adapter

One of our customers performed an experiment to determine the uniformity of silica bead suspension (3 micron diameter, specific gravity = 1.98) in a VP 756CP-96 Bubble Paddle Reservoir.   200 ml of a bead slurry was placed into the reservoir and stirred for 2 hours.  Five samples were collected from different points in the middle and around the edges of the reservoir.  The results are plotted below.  The % CV values between the 5 sample points were less than 4.95% at each dilution.  Raw data can be found at this link.
 

Samples were taken of the same silica beads from columns 2, 5, 8 and 11 to determine if the samples were uniform throughout the reservoir.  The CV's were less than 5% within the columns and between the columns.

This same customer conducted an experiment to determine if the silica beads would remain uniformly in suspension after many hours of stirring.  A VP 756CP-96 was loaded with 5 bead pools.  Each bead pool varied in the amount of stirring time done during the pooling phase.  Pool 1 is the control pool.  Each additional pool increases the duration of stirring.  The question was whether there is any significant difference in loading performance of the 5 pools.

1 = Starting suspension, 2 = 1 hr, 3 = 4 hr, 4 = 24 hr, 5 = 72 hr