An integrated portable hand-held analyser for real-time isothermal nucleic acid amplification

摘要

A compact hand-held heated fluorometric instrument for performing real-time isothermal nucleic acid amplification and detection is described.The optoelectronic instrument combines a Printed Circuit Board/Micro Electro Mechanical Systems (PCB/MEMS) reaction detection/chamber containing an integrated resistive heater with attached miniature LED light source and photo-detector and a disposable glass waveguide capillary to enable a mini-fluorometer.The fiuorometer is fabricated and assembled in planar geometry,rolled into a tubular format and packaged with custom control electronics to form the hand-held reactor.Positive or negative results for each reaction are displayed to the user using an LED interface.Reaction data is stored in FLASH memory for retrieval via an in-built USB connection.Operating on one disposable 3 V lithium battery >12,60min reactions can be performed.Maximum dimensions of the system are 150 mm (h) x 48 mm (d) x 40 mm (w),the total instrument weight (with battery) is 140 g.The system produces comparable results to laboratory instrumentation when performing a real-time nucleic acid sequence-based amplification (NASBA) reaction,and also displayed comparable precision,accuracy and resolution to laboratory-based real-time nucleic acid amplification instrumentation.A good linear response (R2=0.948) to fluorescein gradients ranging from 0.5 to 10 mu M was also obtained from the instrument indicating that it may be utilized for other fluorometric assays.This instrument enables an inexpensive,compact approach to in-field genetic screening,providing results comparable to laboratory equipment with rapid user feedback as to the status of the reaction.