Miniaturized Protein Microarray with Internal Calibration as Point-of-Care Device for Diagnosis of Neonatal Sepsis

Abstract

Neonatal sepsis is still a leading cause of death among newborns. Therefore a protein-microarray for point-of-care testing that simultaneously quantifies the sepsis associated serum proteins IL-6, IL-8, IL-10, TNF alpha, S-100, PCT, E-Selectin, CRP and Neopterin has been developed. The chip works with only a 4 μL patient serum sample and hence minimizes excessive blood withdrawal from newborns. The 4 μL patient samples are diluted with 36 μL assay buffer and distributed to four slides for repetitive measurements. Streptavidin coated magnetic particles that act as distinct stirring detection components are added, not only to stir the sample, but also to detect antibody antigen binding events. We demonstrate that the test is complete within 2.5 h using a single step assay. S-100 conjugated to BSA is spotted in increasing concentrations to create an internal calibration. The presented low volume protein-chip fulfills the requirements of point-of-care testing for accurate and repeatable (CV < 14%) quantification of serum proteins for the diagnosis of neonatal sepsis.

Recent Advances in Electrochemical and Optical Biosensors Designed for Detection of Interleukin 6

“…It is based on the light scattering properties of the biomolecules to study bound antigen-antibody complexes. The variants of optical biosensors that have been introduced so far differ in coupling agent, conjugate label, detecting signal, and transduction model to read the sensor's output [137][138][139][140][141][142][143]. The following sections discuss the general architecture of optical biosensors designed for sensitive detection of IL-6 and the signal amplification strategies adopted in each category to enhance the overall performance of the biosensor.…”

The Impact of Diffusion on Biochemical Assay Kinetics in 3d-Hydrogel Microarrays

“…Therefore, studying the kinetics will verify the binding of analyte molecules prior to applying amplification strategies and will lead to increasing the sensitivity, accuracy and reproducibility of the assay. The same authors (Buchegger et al, 2012) earlier reported about a diagnostic microarray for neonatal sepsis. The microarray is capable of quantifying 9 various sepsis biomarkers.…”

“…Further, it could help deciding the proper design of the array and its ideal processing times. Table 1 The assay processing times with the achieved limits of detection reported by Buchegger et al (Buchegger et al, 2012). Another work by Sauer and co-workers (Sauer et al, 2011) reports on the development of another sepsis diagnostic microarray.…”

“…This is certainly one of the bottlenecks for transferring this technology to the routine diagnostics. To increase the sensitivity of microarrays the following strategies were applied in the literature (Buchegger and Preininger, 2014;Moschallski et al, 2013;Buchegger et al, 2012;Ramachandran et al, 2005):…”

The use of laboratory biomarkers for surveillance, diagnosis and prediction of clinical outcomes in neonatal sepsis and necrotising enterocolitis

“…The concept has already been proven to be feasible using a miniaturised protein microarray chip that could simultaneously quantify nine cytokines/chemokines and acute-phase proteins, including IL-6, IL-8, IL-10, tumour necrosis factor-α (TNF-α), S-100, procalcitonin, E-selectin, CRP and neopterin, with only 4 µL of serum 21. The measurement could be completed within 2.5 h using a single-step assay.…”