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It is commonly necessary to survey a large number of persons for genetic profiles or even for single loci to build databases and for other purposes. It is also necessary to make biological collections from naïve and shocked persons, particularly children that are still very deeply distressed from being a victim of some recent offense.

In these situations, and others, there is always the problem of gaining the cooperation of naïve, fearful and potentially hostile subjects in the collection of tissue samples from their bodies.

Collection from children and naïve subjects must be carried with a painless methodology like buccal cell collection, but it also requires unthreatening instruments, ideally highly familiar instruments, that do not need to be explained to children. The collection process should be conveniently performed in their home, school, local medical center or even in a public place without special instruments or other items that draw attention by being threatening or even unusual.

The collected samples should be:

Easily and reliably processed for DNA information.

Amenable for automated processing.

Amenable for hand processing.

All the above criteria were met by use of a simple combination of disposable toothbrush ("BuccalbrushÔ") and FTAÔ paper.

Buccal cells were collected by gently rubbing a wet, single-use BuccalbrushÔ to the inner cheek epithelium and tapping the brush onto the surface of FTAÔ paper.

To simply monitor the cell-transfer, the buccal brush was routinely wetted with a saline solution containing a little food coloring before placing in the mouth.

The saline used in these experiments has no highly critical properties so that customized salines with different food colorings and even various flavorings should be quite acceptable.

The brush is dipped in the saline with food coloring, rubbed on the inner cheek in a similar way to brushing teeth then tapped, bristles down, onto the FTAÔ paper.

The suspension of cells lodges on the paper as a lightly colored imprint of the brush, the reagents in the paper lyse and preserve the buccal cell’s contents. The dried FTAÔ paper with colored imprint is then stored or processed for DNA analysis.

Processing for PCR, either by hand or by automated procedures, consists of simple washing with FTAÔ Purification Reagent followed by drying and direct PCR without DNA extraction. Processing for RFLP requires another washing step and a restriction.