*PCR (polymerase chain reaction) is covered by patents held by Hoffman-LaRouche
Products
CleanSpot PCR Workstation

The CleanSpot is designed to fulfill a very important need today... control of PCR* contamination.

Just 25 - 30 minutes of UV irradiation in the Coy Clean Spot can prevent unwanted PCR contamination. The Clean Spot is the easiest and most economical method for DNA (RNA) purification.

The combination of a special light reflector and two powerful overhead UV bulbs generate Pyrimidine Dimers (T,C) and other photo defects in contaminating target sequences, thus eliminating falsely primed products that result in countless lost time and expense.

The CleanSpot is designed to prevent unwanted contaminant DNA in amplification mixtures, thereby saving many lost hours and expensive samples.

The UV resistant acrylic enclosure provides a contained, dead air space in which to set up your reactions and permit safe 254nm UV irradiation of solutions and supplies. This powerful UV wavelength renders DNA contaminants biologically inactive in 30 minutes or less.

The thick front panel is an effective beta irradiation shield as well as acting as a breath guard. An overhead fluorescent light illuminates the work area.

DETAILED DESCRIPTION

DNA sequences often contaminate reagents, buffers, equipment, tubes and tips commonly used for PCR* reactions, resulting in needless lost time and expense.

For years it has been known that UV light can damage DNA. UV exposure of 30 minutes or less in the Cleanspot PCR Work Station can prevent unwanted amplification of contaminant DNA. The combination of unique reflectors and powerful overhead UV lights introduces pyrimidine dimers and other photo damage into the contaminating target sequences, making them non-amplifiable.

The amplification process produces large quantities of DNA that are handled at various analysis stations, and even laboratories using extreme care in handling the samples will have the product permeate through the lab. One copy of this product DNA or other extraneous DNA in an experimental reaction mixture can be amplified, leading to false positives or erroneous results. This contaminant DNA is typically introduced during reaction set up, being carried into the mixture by:

  1. Contaminated tubes, tips, pipettes;
  2. Sirborne particles laden with DNA;
  3. Fouled reaction components.

The PCR Workstation is designed to combat the three major contaminant pathways. Reaction preparation and equipment/supply storage is performed in the "clean," enclosed, still air chamber, thus minimizing airborne and supply borne contamination. During reaction preparation, part of the reaction mix is exposed to the UV light, thus decontaminating any fouled reaction components. Since this exposure bathes the chamber and its contents, they are "cleaned" at the same time. By keeping the doors latched, the enclosed chamber and supplies are ready for the next use.

Multiple Item Irradiation
Large enclosed work area permits continuous irradiation of many items simultaneously.

More Effective Irradiation of Reaction Mixtures, Reagents and Supplies
Unique light reflector allows all UV light to be directed to the work area, providing more effective irradiation of reaction mixtures, reagents, pipette tips, and pipettors.

Reduced Operator Exposure to UV
Safety device switches off the lamps preventing user exposure inside chamber. Acrylic absorbs UV light for added safety.

Eliminates Falsely Primed Products in 30 minutes or less
The shelf can be used as an exposure area to reduce decontamination time.

White Light Illumination
Overhead white light illuminates the work area for non-UV light applications.

(32)P Workstation, Ideal for Cycle Sequencing Preparation
Thick 3/8 inch acrylic front panel is an effective beta shield, providing protection from beta radiation emitted from (32)P.

Isolating Environment
The enclosed benchtop work area provides a convenient, "clean," still air environment in which to set up reactions.

Easy to Install and Clean
The chamber breaks down into 4 component parts without the use of tools.

Advantages Over Other Methods
In addition to enjoying cost advantages over laminar hoods, the CleanSpot can have performance benefits due to the enclosed work area and UV lights. The amplified DNA is not altered, as with chemical decontamination methods. An important facet in preventing contamination, the isolated, "clean" set up area is missing when trans-illuminators or crosslinkers are used as radiation sources. Also, these light sources may not emit light at a high enough intensity or at the proper wavelength to efficiently inactivate the contaminant DNA.

PERFORMANCE INFORMATION

A. Pure Target
100% of sequences can be amplified. 10 ng of a previous PCR product resuspended in 4ul of distilled H2O were allocated into a series of tubes. All tubes were run through UV light irradiation and 1 tube was removed every 10 minutes. Each tube was then cycled through 30 rounds of PCR using primers specific to the material PCR and 10ul of each reaction was run on an agarose gel. Tubes were on their sides and capped.

B. Human Genomic DNA Target
1. Repetitive sequence DNA primers were used on total genomic DNA which was irradiated over a time course of 10 to 30 minutes and each tube was cycled through 30 rounds of PCR using repetitive DNA primers. 10ul of amplified DNA was run on a agarose gel. 20 minutes of irradiation was required to deactivate 20ng of target. Tubes were on their sides and capped.

2. 50 ng of total human DNA resuspended in 4ul of distilled H2O was irradiated over a time course of 10 to 30 minutes. Each tube was cycled through 30 rounds of PCR using a primer set specific for a single gene. 20 minutes completely deactivated the template.

The irradiation times given in A and B above can be reduced by placing the items to be decontaminated on the shelf in the chamber. Since the light is about two times more intense on the shelf, the time required to deliver the same amount of energy to the items is 1/2 that at the chamber base where tests A and B were done.

Suggested irradiation times take into account the intensity given off by the UV lights and the natural decay in this intensity over time. A decrease of 20% in intensity is seen after 1500 hours of continuous operation. Since this decay is accelerated by switching the bulb on and off. we suggest changing the bulbs every year.

Current users are finding the CleanSpot very useful in eliminating contamination problems in labs where amplification of the same gene has been done for a long time.