tailieunhanh - báo cáo khoa học: "A signal amplification assay for HSV type 1 viral DNA detection using nanoparticles and direct acoustic profiling"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: A signal amplification assay for HSV type 1 viral DNA detection using nanoparticles and direct acoustic profiling | Uludag et al. Journal of Nanobiotechnology 2010 8 3 http content 8 1 3 JOURNAL OF NANOBIOTECHNOLOGY RESEARCH Open Access A signal amplification assay for HSV type 1 viral DNA detection using nanoparticles and direct acoustic profiling Yildiz Uludag1 Richard Hammond2 Matthew A Cooper2 3 Abstract Background Nucleic acid based recognition of viral sequences can be used together with label-free biosensors to provide rapid accurate confirmation of viral infection. To enhance detection sensitivity gold nanoparticles can be employed with mass-sensitive acoustic biosensors such as a quartz crystal microbalance by either hybridising nanoparticle-oligonucleotide conjugates to complimentary surface-immobilised ssDNA probes on the sensor or by using biotin-tagged target oligonucleotides bound to avidin-modified nanoparticles on the sensor. We have evaluated and refined these signal amplification assays for the detection from specific DNA sequences of Herpes Simplex Virus HSV type 1 and defined detection limits with a MHz fundamental frequency thickness shear mode acoustic biosensor. Results In the study the performance of semi-homogeneous and homogeneous assay formats suited to rapid single step tests were evaluated utilising different diameter gold nanoparticles at varying DNA concentrations. Mathematical models were built to understand the effects of mass transport in the flow cell the binding kinetics of targets to nanoparticles in solution the packing geometries of targets on the nanoparticle the packing of nanoparticles on the sensor surface and the effect of surface shear stiffness on the response of the acoustic sensor. This lead to the selection of optimised 15 nm nanoparticles that could be used with a 6 minute total assay time to achieve a limit of detection sensitivity of X 10-12 M. Larger diameter nanoparticles gave poorer limits of detection than smaller particles. The limit of detection was three orders of magnitude lower than