Amperometric Self-Referencing Ceramic Based Microelectrode Arrays for D-Serine Detection

Abstract

D-serine is the major D-amino acid in the mammalian central nervous system. As the dominant co-agonist of the endogenous synaptic NMDA receptor, D-serine plays a role in synaptic plasticity, learning, and memory. Alterations in D-serine are linked to neuropsychiatric disorders including schizophrenia. Thus, it is of increasing interest to monitor the concentration of D-serine in vivo as a relevant player in dynamic neuron-glia network activity. Here we present a procedure for amperometric detection of D-serine with self-referencing ceramic-based microelectrode arrays (MEAs) coated with D-amino acid oxidase from the yeast Rhodotorula gracilis (RgDAAO). We demonstrate in vitro D-serine recordings with a mean sensitivity of 8.61 ± 0.83 pA/µM to D-serine, a limit of detection (LOD) of 0.17 ± 0.01 µM, and a selectivity ratio of 80:1 or greater for D-serine over ascorbic acid (mean ± SEM; n = 12) that can be used for freely moving studies.

Investigating brain d‐serine: Advocacy for good practices

“…Such a measurement needs careful experimental design, appropriate analytical techniques and proper execution in order to be confident in differentiating D-serine from other amino acids and from its L-enantiomer in biological samples. Analytical methods have matured, and we now have an array of techniques ranging from biosensors, [25][26][27] high pressure liquid chromatography (HPLC) [28][29][30] and LC/ LC 31 to LC/mass spectrometry 32,33 or capillary electrophoresis-laser-induced fluorescence (CE-LIF) [34][35][36] with well described protocols to detect and measure D-AAs (including D-serine) even at very low levels in complex matrices like biological samples. Despite the availability of multiple approaches to confirm D-serine, analysis of recent publications suggests that this D-AA was not always quantified with the controls that are outlined in Box 1 and Figure 1.…”

Biosensors for D-Amino Acids: Detection Methods and Applications

“…This technique could be useful to investigate the role of D-Ser in brain development and diseases by mapping its local release from astrocytes and neurons. RgDAAO was also used as bioreceptor for an amperometric sensor for D-Ser with selfreferencing ceramic-based microelectrode arrays [75]. This system used two channels, each consisting of a pair of platinum recording sites named D-AAs detecting channels and sentinel channels, which are spaced only tens of micrometers apart.…”

Upconversion NaYF4:Yb/Er–TiO2–Ti3C2 Heterostructure-Based Near-Infrared Light-Driven Photoelectrochemical Biosensor for Highly Sensitive and Selective d-Serine Detection

“…In recent decades, several strategies have been established based on the enantiospecificity of D-amino acid oxidase (DAAO). For instance, disk-shaped biosensors, 9 DAAO-coated ceramic-based microelectrode arrays, 10 and microanalysis systems 11 To the best of our knowledge, a photoelectrochemical (PEC) method has not yet been developed for D-ser detection. PEC bioanalysis was developed based on the principle of converting light to electrons and has recently attracted considerable research attention owing to its high sensitivity, low cost, and rapid response.…”

“…In recent decades, several strategies have been established based on the enantiospecificity of d -amino acid oxidase (DAAO). For instance, disk-shaped biosensors, DAAO-coated ceramic-based microelectrode arrays, and microanalysis systems have demonstrated good d -ser detection performance. Nevertheless, their narrow detection ranges and low sensitivities impede their practical application.…”