ABSTRACT
Whole-cell biosensors incorporate living cells as integral compo-
nents of a sensing device. The biological elements may be natural
prokaryotic or eukaryotic cells or genetically engineered variants
thereof, isolated proteins, including antibodies, or other isolated
cellular components. These biological elements are then integrated
in some fashion to an electronic device, which then (measures or)
transduces the biological signal into a form that can be directly
analyzed, stored, or transmitted (for further analysis). A variety of
transducing methods have been developed, including colorimetric,
fluorescent, electrochemical, and bioluminescent approaches [1,
2]. The use of bioluminescent reporters has been widely adopted
for chemical sensing because of their sensitivity, specificity, range,
relative simplicity, and suitability for real-time analysis [3]. Here
prokaryotic or eukaryotic cells are engineered to emit light in
response to an environmental stimulus. The genetic engineering
usually involves inserting the promoter of a gene that is naturally
upregulated in response to a specific stimulus, in front of luciferase
structural genes. Thus under the conditions that upregulate a
specific gene, gene expression of the luciferase genes is induced
and light is emitted. As it is conventionally practiced the emitted
light is generally detected by a benchtop photodetector instrument
that typically uses a photomultiplier tube (PMT). With the initial
goal of creating a mobile device, we have miniaturized the light de-
tection apparatus using complementary metal-oxide semiconductor
(CMOS) technology tomake a bioluminescent bioreporter integrated
circuit (BBIC).