Evolution in Instrument Design of Inexpensive but Highly Sensitive Devices for the Life Sciences

 

Patrick Lai, Matthew Patterson, Kim Willoughby, Neil Berezowski, Mark Mahadeo, Mohamed Hassanin & Elmar J. Prenner

Tested Studies in Laboratory Teaching, 2014, Volume 35

Abstract

Absorbance and fluorescence spectroscopy are very common tools in undergraduate teaching within the life sciences. However, instrument costs are always a limiting factor for the number of devices available in a student laboratory. Earlier generations of instruments used simple unstabilized LED excitation and LCD displays for data output but already showed the remarkable sensitivity of ng/mL detection of DNA. In addition, their modular design allowed combining a multitude of excitation windows and emission ranges for any dye of choice. Later generation instruments added enhanced electronic control, stirring and temperature control capabilities, and especially USB connectivity, which allowed for software controlled measurements and data storage on a PC. The latest generation instruments, now in the Beta stage, have stabilized LED output and even more sensitive detectors, enabling DNA detection in the pg/mL range. As well, very low standard deviations allow quantitative fluorescence based detection of analytes, such as DNA, protein, or ions. The second limiting factor in many laboratory budgets are reagent costs, which limits the use of expensive fluorophores or kits in at least the larger classes. Thus, the combination of a custom-made device for a dye of choice that also fits a teaching lab budget is the ultimate goal. A range of novel and very sensitive dyes, developed by SETA BioMedicals, were selected to design a teaching instrument capable of detecting DNA (pg/mL) and protein (µg/mL) that uses bulk detection kits and is optimized to allow larger class access to state-of-the-art spectroscopic experiments.

Keywords:  Instrumentation, fluorescence spectroscopy, absorbance spectroscopy

University of Calgary (2013)