Protedyne Corporation

Versatility

As the trend towards assay miniaturization continues with increasing demands to make nanoliter transfers, here is a simple way to convert a High Resolution Engineering Robot into a 96,  384 or 1,536 pin tool.

The Protedyne Corporation Robot  delivers an entirely new screening platform to address assays.    These features enable users to save time and money, while addressing their preferred screening targets.

Cleaning The Pins

Procedures for transferring liquids, robot speed, wash solutions, blotting protocols and pin cleaning can found at this hyperlink.  Cleaning the pins between mother plates is easy and effective.  In an experiment to determine the amount of carry over after 100 transfers of concentrated FITC (mother to daughter plate) we were only able to detect  0.000,001,8% of the residual FITC on the pin using only two static 100 ml wash baths.  To put this into perspective, it is equivalent to removing all but 18 molecules out of a possible 1,000,000,000 molecules. This experiment was repeated using DMSO as the first wash solution and virtually identical results were obtained, indicating the thoroughness of the wash.

For comprehensive data on nanoliter dispensing with pin tools see the following pages.
 

• DMSO and Aqueous delivery with hydrophobic coated and uncoated solid and slot pins
   

• DMSO and Aqueous delivery with solid and slot pins
   

• Pin tool data page

  Factors Affecting Pin Delivery Volumes

The list on the right summarizes the factors that contribute to the volume delivered.  With each application these factors can be controlled and standardized so that the delivery volumes are very reproducible.  With most applications the CV's are less than 5%.

V&P pins transfer liquid by carrying the liquid on the sides, tips and in slots we cut into the tips. The amount delivered is determined by the diameter and surface tension of the pin, the surface tension of the liquid, how far the pin is submerged into the liquid and the speed with which the pin is removed from the liquid.  When all of these variables are fixed, the accuracy of the liquid transfer is very consistent, with CV averages better than 5%.

Increasing the speed of withdrawal from the source plate by 7- fold will increase the volume delivered by as much as 3 fold in a linear relationship.  This phenomenon can be exploited to expand the range of delivery volume for a single pin. The table and the chart below illustrates the effects of increasing the speed 7- fold.  The speed range is from 0.78 cm/sec to 5.7 cm/sec.  Use this chart to select the pin that will deliver in your desired range.

  Select The Volume You Need To Transfer For Your Application

 DMSO Liquid To Liquid Transfers With Uncoated Pins

*# delivery volume range is determined by speed of withdrawal from source liquid.
slow speed  = 0.78 cm/sec = low volume delivery range
fast speed  =  5.70 cm/sec = high volume delivery range
Follow this link to assay methods

The links below are to delivery volume range tables for uncoated and hydrophobic coated delivering either DMSO or Aqueous solutions.
 

DMSO TRANSFERS WITH HYDROPHOBIC COATED PINS

DMSO TRANSFERS WITH UNCOATED (STAINLESS STEEL) PINS

AQUEOUS TRANSFERS WITH HYDROPHOBIC COATED PINS

AQUEOUS TRANSFERS WITH UNCOATED (STAINLESS STEEL) PINS

  A Guide For Selecting The Right Pin For Your Application

1. What volume do you need to  transfer?   DMSO? Aqueous? See these hyperlinked tables to determine your options.  Also consider custom slot pins.

2. Will the source plate have wells with significantly different levels of liquid?  (Cherry picked source plate or edge drying effect?).  If yes and if the absolute volume transferred is critical, then select the largest slot pin that is in your transfer range.  This will minimize the effect of liquid height on the volume of liquid carried on the sides of the pin.  Also consider custom slot pins.

3. Does the material transferred bind non-specifically to stainless steel?  If yes then select the Hydrophobic/lipophobic coated pins.  If no, select the uncoated pins.

4.  What is the Z clearance on the robot deck from the highest impediment (top of the source plate/recipient plate/wash reservoirs, etc.) to the top of the robot mounting plate?  If it is greater than 77 mm you can use our our 30 mm exposed length FP(#T) or the 17 mm exposed length FP(#) series pins.  If it is less than 77 mm, you can only use the shorter FP(#)C series pins (12 mm exposed pin length pins and the E-clip series pins (23 mm exposed pin length..  If it is less than 60 mm, we recommend you contact us.  There are a few tricks we can do to shave off 5 to 10 mm in height. 

Links to the specifications of all the robot mounting plates/pin tool/pin combinations can be found on the height ("Z") restriction page. 

5.  Is the source plate a deep well plate?  If so you may need to use a 30 mm long exposed length pin ("T" pin) to reach down to the lower levels of the well. 

6.  Should you choose the solid pin versus the slot pin? Although the there appears to be a slight advantage for slot pin, CV's between the two pins are very good.  Both are easy to clean between specimens.  Biggest factor is cost.  If you don't need to deal with varying liquid heights and you can obtain the volume necessary with a solid pin, choose the economical solid pin.

7.    If you are still uncertain about which pin to select for your application, you can perform a simple "Proof of Principle" test with several different pins using our inexpensive VP 450FP3 Replicator Strip coupled via a VP 452MP to one of our robot mounting plates.   An even simpler solution is to use a work station with a 1, 4 or 8 probe dispense head with the new V&P Mono Pin Tool to test the various pins.

Defining A Pin Tool

Originally we sold our pin tools with unique part numbers.  As we have added more pins to our selection and more robot systems to mount the pin tools to, the number of unique part numbers grew exponentially to an un-manageable size.  Our solution has been to specify a pin tool by the 3 component parts that compromise the Pin Tool.  The Pins, the Floating Fixture and the Robot Mounting Plate.  If you have previously ordered a pin tool by unique part number, we will be able to provide the same pin tool to you.

Ordering Your Pin Tool As Simple As 1, 2, 3

A Protedyne Corporation pin tool consists of two separate parts.

1.  The pins, (#FP___)
2.  The Floating Frame Fixture (384 or 1536) (#AFIX___FP_)

For example the part numbers for pin tool in the photo to the right would be FP1, AFIX1536FP1

To order, just tell us those 2 part numbers and we will assemble your Pin Tool.

  1. Choose The Pin

1. Choose the pin to match your application, pin length, delivery volume requirements and/or the non-specific binding nature of the sample.

Solid Pins

Solid pins are the most economical and control volume transferred by pin diameter.

Solid pins for Protedyne Corporation are available in 2 exposed pin lengths; 12 and17mm.  The 12 mm ("C") pins are used with a 1536 and the 17 mm ("N") pins are used when transferring from a 384 or 1536.

Slot Pins

Slot pins have several advantages over solid pins:

1. Slot pins carry a larger volume than solid pins in liquid to liquid transfers.
    

2. Slot pins are not as sensitive to the depth of the mother liquid as solid pens.
    

3. Slot pins deliver a larger volume than solid pins in liquid to dry plate transfers.
    

4. Slot pins deliver a larger volume than solid pins in liquid to membrane transfers.
    

5. Slot volume is customizable.
    

6. Slot pins can deliver to dry plates by pre-wetting the plate.

**NEW** Hydrophobic/Lipophobic Coated Pins

Hydrophobic/lipophobic coated pins are very useful in handling solutions with proteins or lipids that may stick to naked stainless steel.  Both solid and slot pins can be coated.  Click here for more details on the nature of our hydrophobic/ lipophobic coating and the coating process.

The tables below contain hyperlinks to the various types/lengths/diameters/coatings of the pins we offer.

  Tube Style Pins

Please visit this hyperlink for Pin Tool Data And Charts on hydrophobic pins.

  2. Choose The Floating Fixture

2. Choose the Floating Fixture to match your application.  Standard are 384 and 1,536 formats.

These floating fixtures consist of an upper float plate that will all accommodate a 1.58 mm diameter tube, a lower float plate that will accommodate either a .457 mm  or .787 mm  diameter pin and 6 standoffs that keep the two plates separate.  The length of the standoffs is determined by the length of the pin used.  Your application will determine if you select the 384 or 1,536 formats and your previously made pin selection will determine the diameter of holes in the lower float plate.  Click here for a complete selection of these floating fixtures..

If you have more specific needs call us for help at (800) 455-0644.

Call Protedyne Corporation for pricing information and tell them the part numbers you need for
the pin tool - Pin # (FP___)
Floating Frame Fixture # (AFIX__FP__ )

Replacement Pin Link for the Tube style Molcular Devices Pin Tools.

The Double Float Plate Molecular Devices Tube Style Pin Tools have several advantages over the E-Clip Style Pin Tools:

1. The Tube Style Pin Tools are smaller in diameter and deliver very small volumes (down to 2 nl and as much as 500 nl depending on diameter and slot size).
    

2. Smaller pin diameters also result in more precise delivery volumes (CV's ~4%).
    

3. Because the pin is registered between 2 float plates over a greater height, the pin angle will be truer (closer to 90^°) when they touch the surface. 
    

4. The smaller hole on the lower float plate allows us to make very tight tolerances on the fit between the pin and the hole.  This results in very precise placement of the pins on the surface so that very high density arrays can be made without overlapping the spots.

 
  Custom Floating Slot Pin Replicators

Custom Floating Slot Pin Replicators can also be made using the 0.457 mm and 0.787 mm diameter pins and placing them into the Floating Pin Replicators described above.  The slot volumes between these two pins can cover a range of volumes from 5 nl to 1000 nl by changing the width and depth of the slot.  Inquire by phone or e-mail for more information.

  Cleaning Pins On A Molecular Devices Mounted Pin Tool

The most important aspect of using pin tools is to start with clean pins and then keep them clean so they will consistently deliver the same volume.  We recommend our Pin Cleaning Solution (VP 110) to clean the pin of protein and other residue buildup before you start an assay.  To quickly and efficiently remove the previous transfer from the pin we have several different wash reservoirs, flowing reservoirs and fountains to clean 384 and 1536 floating pin tools.  These wash stations also are adapted so the blotting station is part of the washing station thus reducing the cleaning cycle time and the number of robot stations required for the cleaning process.  We also have other independent blotting stations (VP 540D).

Integral to the cleaning process of all pins is the blotting step between baths.  Lint particles in the slots or on pin tips, from standard paper towels, will interfere with the loading and unloading of liquid.  We have solved this problem.  The VP 540DB blotting system is a tray with the standard microplate foot print that contains a super absorbent polypropylene pad covered by a Lint Free Blotting Paper.  We strongly recommend that you use this or our other lint free blotting systems.

  Pin Tool Accessory Kit

We highly recommend that you order the Pin Tool Accessory kit at the time you order the pin tool.  This "essentials" accessory kit contains the Docking Station for the Pin Tool on the robot deck giving you the capability for "Hot Swapping" the pin tool for other accessories, The VP 540DB Lint Free Blotting System is used to clean the pins efficiently between samples, two VP 540 Wash Reservoirs to wash the pins between source plates, the VP 110 Pin Cleaning Solution is used the clean the pins daily, the VP 425 Pin Cleaning Brush is used if a build up occurs.   Although we have several other wash and blot accessories available these are the most cost effective for the majority of applications.  If you elect to use the fountain and flowing reservoirs we still strongly recommend the other items in this kit.