Paper-Based Progesterone Sensor Using an Allosteric Transcription Factor

Abstract

Progesterone monitoring is an essential component of in vitro fertilization treatments and reproductive management of dairy cows. Gold-standard biosensors for progesterone monitoring rely on antibodies, which are expensive and difficult to procure. We have developed an alternative transcription factor-based sensor that is superior to conventional progesterone biosensors. Here, we incorporate this transcription factor-based progesterone sensor into an affordable, portable paperfluidic format to facilitate widespread implementation of progesterone monitoring at the point of care. Oligonucleotides labeled with a fluorescent dye are immobilized onto nitrocellulose via a biotin–streptavidin interaction. In the absence of progesterone, these oligonucleotides form a complex with a transcription factor that is fluorescently labeled with tdTomato. In the presence of progesterone, the fluorescent transcription factor unbinds from the immobilized DNA, resulting in a decrease in tdTomato fluorescence. The limit of detection of our system is 27 nm, which is a clinically relevant level of progesterone. We demonstrate that transcription factor-based sensors can be incorporated into paperfluidic devices, thereby making them accessible to a broader population due to the portability and affordability of paper-based devices.

Paper-based sustainable biosensors

“…32–34 However, the lack of biorecognition elements impedes the development of diverse biosensors. 35 The transducer-based output signals include optical ( e.g. , absorbance, luminescence, chemiluminescence, and surface plasmon), 36 mass ( e.g.…”

“…Also, the LOD of the device was 27 nm, which is the clinically significant level of progesterone. 35…”

“…[32][33][34] However, the lack of biorecognition elements impedes the development of diverse biosensors. 35 The transducer-based output signals include optical (e.g., absorbance, luminescence, chemiluminescence, and surface plasmon), 36 mass (e.g., piezoelectric and magnetoelectric), 37 thermometric, 38 and electrochemical signals. 39 Electrochemical biosensors can be categorized into amperometric, potentiometric, voltammetric, impedimetric/ conductometric, and capacitive sensors.…”

“…Also, the LOD of the device was 27 nm, which is the clinically significant level of progesterone. 35 The use of nanomaterials in combination improves the efficiency of biosensors, for example, a disposable paperbased chemiresistive biosensor with manifold detection capability and microfluidic controls using single-walled carbon nanotubes (SWCNTs) was developed for label-free immunosensing. In this study, a stable water-based ink composed of pyrene carboxylic acid (PCA) and SWCNTs was synthesized and deposited on paper in a facile approach, which did not require extra covers or patterns.…”