Printed Paper Sensors for Serum Lactate Dehydrogenase using Pullulan-Based Inks to Immobilize Reagents

Abstract

In this study, a paper-based point-of-care (POC) colorimetric biosensor was developed for the detection of lactate dehydrogenase in serum using a nonporous, oxygen impermeable reversibly gelling polysaccharide material based on pullulan. The pullulan could be printed onto paper surfaces along with all required assay reagents, providing a means for high-stability immobilization of all reagents on paper. Serum containing lactate dehydrogenase (LDH) was directly spotted on to the pullulan-coated bioactive paper and provided quantitative colorimetric data that was comparable to that obtained with a conventional plate-reader method. The paper strip was found to be highly stable and could be stored at 4 °C for at least 10 weeks with no loss in performance, as compared to a complete loss in performance within 1 day when the reagents were printed without the stabilizing polysaccharide. The ease of fabrication coupled with the high stability of the printed reagents provides a facile platform for easily manufactured POC sensors.

Target‐Induced and Equipment‐Free DNA Amplification with a Simple Paper Device

“…Communications dNTPs and hemin, 3) printing the above mixture into the circular test zones as described previously, [17] and 4) air-drying (see SI for details). Thetransparent pullulan films (letter "P" can be seen) with the encapsulated RCAr eagents are obtained on the paper array after drying ( Figure 4B).…”

Colorimetric Sensor Arrays for the Detection and Identification of Chemical Weapons and Explosives

“…For example, arrays can be made by incorporating ink with slotted pins onto sensor sol–gel formulations and standard chromatography paper (Bang et al., 2008). Other methods of sensor immobilization onto solid supports include the use of polymer particles (Soga et al., 2013), sol–gel particles (Bang et al., 2008), gels (Curto et al., 2012), and polymer membranes and films (Bueno et al., 2015; Kannan et al., 2015). Immobilizing agents can provide several additional benefits including improved selectivity (Soga et al., 2013), protection from the environment, and extended shelf life (Kannan et al., 2015).…”

Covalent functionalization and electrochemical tuning of reduced graphene oxide for the bioelectrocatalytic sensing of serum lactate

“…7 The development of highly sensitive sensors for the detection and quantification of serum lactate is in demand in clinical diagnosis, biotechnology and sports medicine. Although several methods based on chromatography, spectrophotometry are available, [8][9][10][11][12] the analysis involves complex procedures. The amperometric method gained considerable interest in the biosensor industry as it does not require expensive equipment or tedious procedures.…”