Aliquoting is one of the first steps in biological sample processing whereby the sample or a portion of the samples is taken from the collection device and placed in an appropriate testing container for further processing. The testing of buccal cells on cotton-tipped or Dacron applicators in large scale DNA profiling from known individuals or forensic evidence is desirable because the collection of the sample is relatively easy, collection materials are inexpensive, and if collected properly, the cells on the swab yield a sufficient quantity of DNA. Unfortunately, unlike the processing of paper based collection substrates, there are in general no automated methods for introducing the buccal sample on the applicator into the laboratory testing process. Currently, sample introduction or aliquoting practices require the forensic analysis to manually cut or transfer each swab and place it into the correct well in a sample plate or tube. This process is labor intensive, typically requires a witness, and if not performed properly, can lead to the occurrence of sample switches or misidentifications.
Further, other contact methods, such as a mechanical shear technique, are used to cut biological samples on paper. The mechanical shear technique is based on cutting the sample with such devices as a punching unit, a razor blade, or scissors. Mechanical shear techniques are relatively simple but are also inflexible. Since these methods involve direct contact with the sample, there is also an increased chance of sample-to-sample contamination during the cutting operation. For situations where contamination or carryover is an issue, the cutting device may need to be cleaned or replaced between the cutting of samples, which can be expensive and time consuming. Also, contact methods can introduce static electricity which can sometimes lead to the sample “jumping.” This inadvertent movement can lead to sample mix-up and misidentification. Currently there are no automated methods for cutting three-dimensional sample collection devices such as swabs, sponges, or three-dimensional paper devices.