The aim of the novel technologies project was to investigate the validity and applicability of emerging technologies. For the purposes of this project, two areas of research were chosen: The first was to investigate factors affecting solid phase hybridisation's, with specific reference to the use of this methodology in DNA arrays. Using a LightCycler ™, and a solid-phase hybridisation system investigations were undertaken to determine: (1) The effect a G/C content on melting temperature of short (20-30bp) oligonucleotide duplexes. (2) The effect of varying numbers of mismatches on melting temperature. (3) The effect of single-stranded overhangs on melting temperature of hybrids of varying G/C content. (4) Determination of the best concentration of cosolvent to use in solid-phase hybridisation to achieve a single hybridisation temperature, which could be used for DNA probes of equal length, regardless of their G/C content. (5) The stringency that can be achieved by the use of cosolvents in a solid phase hybridisation system. This work has been fully reported (Birch & Frankling, 1999) and will not be discussed in detail here. Briefly, it was concluded from these studies that the use of TMAC and betaine in the membrane based hybridisation assay showed great potential in reducing the effects of G/C content on assay specificity.
The second area of research undertaken in this project was to investigate the validity of a new microfluidic LabChip„· system, the Bioanalyser 2100 (Agilent Technologies). This system was used as a novel approach to quantify GMOs in foodstuffs and was compared to a gel based method; this work forms the basis of the following report. Briefly, reference materials of known GM content were obtained from the European Commission and these were used to produce ¡§blind¡¨ samples of known GM content. A PCR based assay was used for both methods. The total Soya content of the reference standards was normalised using the ¡§housekeeping¡¨ gene lectin. Using GM specific primers, a standard curve of GM content was produced for each method and this was used to determine the GM content of the ¡§blind¡¨ samples. Statistical analysis was performed for both methods and it was determined that there was a level of variability in both methods, but there were no significant differences between duplicate experiments using the Bioanalyser 2100 method. The calculated values for GM content of the blind samples did not differ significantly form the known values. It was concluded that both methods could be used to determine GM content of unknown samples, but the data was at best semi-quantitative. The Bioanalyser 2100 method was found to be more accurate and user-friendly than the gel method and may offer a better alternative to gel based methods.