Journal: ACS nano

Article Title: Integrated Biosensor for Rapid and Point-Of-Care Sepsis Diagnosis

doi: 10.1021/acsnano.7b08965

Figure Lengend Snippet: Peritoneal B1a cells are activated by pathogens and give rise to IL-3+ B cells (IRA, innate response activator). IL-3 acts on hematopoietic stem progenitor cells (HSPC) to promote the emergency generation of inflammatory leukocytes that are released into the circulation. This leads to an uncontrolled cytokine storm, multiple organ failure, and septic shock that may result in death.

Article Snippet: Enzyme-linked immunosorbent assay IL-3 antibody (R&D systems) was diluted to 2 µg/mL concentration in PBS and added to the Maxisorp 96-well plate (Nunc) for overnight incubation at 4 °C.

Techniques:

Journal: ACS nano

Article Title: Integrated Biosensor for Rapid and Point-Of-Care Sepsis Diagnosis

doi: 10.1021/acsnano.7b08965

Figure Lengend Snippet: (A) Assay schematic. IL-3 is captured on magnetic beads directly in plasma or whole blood and labeled antibodies. Electrical signal is generated through enzymatic reaction. The entire assay is performed using a portable device, and complete within <1 hour. HRP, horseradish peroxidase. Ab, antibody. (B) Magnetic kit for sample processing. A magnetic pipette was custom-built to facilitate the sample handling. The plunger mechanism allows for easy collection and dispension of magnetic beads. (C) The base-station, housing measurement electronics, docks with a smartphone and a multi-well tray. An electrode slides in to the system for electrical connection. A smartphone app provides an user-interface for the system control (via Bluetooth) and data upload to a cloud server. (D) Photo of the whole assay system.

Article Snippet: Enzyme-linked immunosorbent assay IL-3 antibody (R&D systems) was diluted to 2 µg/mL concentration in PBS and added to the Maxisorp 96-well plate (Nunc) for overnight incubation at 4 °C.

Techniques: Magnetic Beads, Labeling, Generated, Transferring

Journal: ACS nano

Article Title: Integrated Biosensor for Rapid and Point-Of-Care Sepsis Diagnosis

doi: 10.1021/acsnano.7b08965

Figure Lengend Snippet: (A) Electrical currents are generated on or near the electrode via TMB redox reaction catalyzed by HRP-coated magnetic beads. With 100 mV reduction potential, the current level reached a plateau within 1 min. The current difference between the IL-3 and IgG control samples (ΔI) was used as an analytical metric. (B) IL-3 extraction yields were compared under different incubation conditions: 15 min, 30 min, and 12 hrs. Thirty minute incubation was sufficient. (C) Signal-to-noise ratios (SNR) were measured in different media spiked with IL-3 of 1 ng/mL. SNR values were statistically identical among serum, plasma, and whole blood (P = 0.07, one-way ANOVA). (D) Varying concentrations of IL-3 were spiked into human plasma and assayed by IBS and ELISA. The IBS performed 7-times faster and 12-times more sensitive than ELISA. All measurements were performed in triplicate, and the data are displayed as mean ± SD.

Article Snippet: Enzyme-linked immunosorbent assay IL-3 antibody (R&D systems) was diluted to 2 µg/mL concentration in PBS and added to the Maxisorp 96-well plate (Nunc) for overnight incubation at 4 °C.

Techniques: Generated, Magnetic Beads, Extraction, Incubation, Enzyme-linked Immunosorbent Assay

Journal: ACS nano

Article Title: Integrated Biosensor for Rapid and Point-Of-Care Sepsis Diagnosis

doi: 10.1021/acsnano.7b08965

Figure Lengend Snippet: Patient samples (23 from septic and 39 from non-septic patients) were analyzed with the IBS assay. (A) A waterfall plot shows the IL-3 levels measured by the IBS system. Each column represents a different sample (red, septic; grey, non-septic). (B) IL-3 level was higher in septic patients than in non-septic controls (P < 0.0001, unpaired t-test). (C) A receiver-operation characteristic curve was constructed. The area under the curve (AUC) was 0.91 with IBS and 0.73 with ELISA. The optimum threshold value that maximized both sensitivity and specificity was [IL-3] = 21.7 pg/mL.

Article Snippet: Enzyme-linked immunosorbent assay IL-3 antibody (R&D systems) was diluted to 2 µg/mL concentration in PBS and added to the Maxisorp 96-well plate (Nunc) for overnight incubation at 4 °C.

Techniques: Construct, Enzyme-linked Immunosorbent Assay

Journal: ACS nano

Article Title: Integrated Biosensor for Rapid and Point-Of-Care Sepsis Diagnosis

doi: 10.1021/acsnano.7b08965

Figure Lengend Snippet: IL-3 level could serve as a predictive marker for organ failure free (A) and overall patient survival (B). Log-Rank test was used to compare times-to-event (times-to-organ failure or death) between low and high IL-3 groups. Kaplan-Meier method was used to calculate the survival function with a minimal p-value approach for cutoff optimization.

Article Snippet: Enzyme-linked immunosorbent assay IL-3 antibody (R&D systems) was diluted to 2 µg/mL concentration in PBS and added to the Maxisorp 96-well plate (Nunc) for overnight incubation at 4 °C.

Techniques: Marker