UV irradiation and autoclave treatment for elimination of contaminating DNA from laboratory consumables


      Laboratories employ various approaches to ensure that their consumables are free of DNA contamination. They may purchase pre-treated consumables, perform quality control checks prior to casework, and use in-house profile databases for contamination detection. It is better to prevent contamination prior to DNA typing than identify it after samples are processed. To this end, laboratories may UV irradiate or autoclave consumables prior to use but treatment procedures are typically based on killing microorganisms and not on the elimination of DNA. We report a systematic study of UV and autoclave treatments on the persistence of DNA from saliva. This study was undertaken to determine the best decontamination strategy for the removal of DNA from laboratory consumables. We have identified autoclave and UV irradiation procedures that can eliminate nanogram quantities of contaminating DNA contained within cellular material. Autoclaving is more effective than UV irradiation because it can eliminate short fragments of contaminating DNA more effectively. Lengthy autoclave or UV irradiation treatments are required. Depending on bulb power, a UV crosslinker may take a minimum of 2 h to achieve an effective dose for elimination of nanogram quantities of contaminating DNA (>7250 mJ/cm2). Similarly autoclaving may also take 2 h to eliminate similar quantities of contaminating DNA. For this study, we used dried saliva stains to determine the effective dose. Dried saliva stains were chosen because purified DNA as well as fresh saliva are less difficult to eradicate than dried stains and also because consumable contamination is more likely to be in the form of a collection of dry cells.


      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Forensic Science International: Genetics
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Sullivan K.
        • Johnson P.
        • Rowlands D.
        • Allen H.
        New developments and challenges in the use of the UK DNA Database: addressing the issue of contaminated consumables.
        Forensic Sci Int. 2004; 146S: S175-S176
      1. D. Figarelli, DNA amplification, DNA Analyst Training

        • Dwyer D.E.
        • Saksena N.
        Failure of ultra-violet irradiation and autoclaving to eliminate PCR contamination.
        Mol Cell Probes. 1992; 6: 87-88
        • Tamariz J.
        • Voynarovska K.
        • Prinz M.
        • Caragine T.
        The application of ultraviolet irradiation to exogenous sources of DNA in plasticware and water for the amplification of low copy number DNA.
        J Forensic Sci. 2006; 51: 790-794
        • Hall A.
        • Ballantyne J.
        Characterization of UVC-induced DNA damage in bloodstains: forensic implications.
        Anal Bioanal Chem. 2004; 380: 72-83
        • Rutty G.N.
        • Hopwood A.
        • Tucker V.
        The effectiveness of protective clothing in the reduction of potential DNA contamination of the scene of crime.
        Int J Legal Med. 2003; 117: 170-174
        • Swah K.
        • Sesardić I.
        • Bristol N.
        • Ames C.
        • Dagnall K.
        • Ellis C.
        • Whittaker F.
        • Daniel B.
        Comparison of the effects of sterilization techniques on subsequent DNA profiling.
        Int J Legal Med. 2008; 122: 29-33
        • Linquist V.
        • Stoddart C.A.
        • McCune J.M.
        UV irradiation of polystyrene pipets releases PCR inhibitors.
        Biotechniques. 1998; 24: 50-52
        • Burgess L.C.
        • Hall J.O.
        UV light irradiation of plastic reaction tubes inhibits PCR.
        Biotechniques. 1999; 27 (tables and figures): 252-256