Development and validation of a point-of-care multiplex diagnostic assay for rapid detection of sepsis biomarkers in resource-limited clinical settings

Project Abstract

In resource-limited clinical settings, timely and accurate diagnosis of sepsis remains a critical challenge due to limited laboratory infrastructure, dependence on centralized facilities, and delays associated with conventional culture-based methods. This study reports the development and validation of a point-of-care (POC) multiplex diagnostic assay capable of rapid, simultaneous detection of a panel of sepsis biomarkers directly from whole blood. The assay integrates microfluidic sample processing, isothermal amplification, and a chemiluminescent/aptamer-based readout to deliver a qualitative and semi-quantitative result within 30–45 minutes. The biomarker panel comprises established sepsis indicators including procalcitonin, C-reactive protein, interleukin-6, pro-inflammatory cytokines (TNF-?, IL-1?), lactate, and a panel of pathogen-associated molecular pattern (PAMP) signatures to differentiate bacterial from viral etiologies and assist in antimicrobial decision-making. A multi-disciplinary design approach guided the development, combining rapid sample preparation, minimal instrumentation, and user-friendly operation suitable for frontline healthcare workers. Analytical performance was optimized through combinatorial assay conditions, surface chemistry modifications to reduce non-specific binding, and real-time signal normalization using internal controls. The analytic sensitivity and specificity were evaluated against gold-standard laboratory assays using blinded clinical samples (n=320) collected from diverse resource-limited hospitals and primary care centers. The POC assay demonstrated a limit of detection ranging from 1–50 pg/mL for protein biomarkers and 10^2–10^4 CFU/mL equivalent for bacterial signatures, with an overall diagnostic sensitivity of 92.5% and specificity of 94.2% across the panel. Receiver operating characteristic (ROC) analysis yielded area under the curve (AUC) values above 0.90 for the composite score, indicating robust discrimination between septic and non-septic patients. Clinical validation included stratification by age, comorbidities, and source of infection, revealing consistent performance across pediatric and adult cohorts and in settings with limited electrical supply and intermittent internet connectivity. The assay’s operational stability was assessed under variable environmental conditions (25–40°C, 20–80% relative humidity), with no significant loss of performance after 12 months of accelerated stability testing. A user-centered evaluation demonstrated favorable ease-of-use, minimal training requirements, and a per-test cost substantially lower than conventional hospital-based panels, aligning with the affordability needs of low-resource environments. Preliminary impact assessment suggests that rapid POC results facilitated earlier initiation of targeted antibiotic therapy and reduced hospital length of stay in pilot clinics. Limitations include potential interference by highly lipemic samples and the need for ongoing calibration to accommodate regional pathogen variability. The study concludes that the developed POC multiplex assay provides timely, accurate, and actionable sepsis biomarker data at the point of care, enabling improved clinical decision-making and patient outcomes in resource-constrained settings. Future work will focus on expanding the biomarker panel, integrating wireless data transmission for epidemiological surveillance, and optimizing mass manufacture to facilitate widespread deployment.

Project Overview

What This Project Is About

---

A straightforward, end-to-end study of creating a simple test that can quickly detect several signs of sepsis using samples from patients. It focuses on making a small, portable test that can be used in clinics with limited instruments and resources, delivering results fast so clinicians can act sooner.

---

---

The Problem It Addresses

---

In many places, advanced lab equipment is not available, causing delays in diagnosing sepsis, a dangerous infection. This project aims to fill that gap by developing a test that is easy to use, affordable, and reliable in basic clinical settings, helping more patients receive timely care.

---

---

Objectives of the Project

---

1. Identify key sepsis biomarkers to include in a quick test panel.
2. Design a user-friendly, low-cost assay that works without complex instruments.
3. Validate the test’s accuracy against standard laboratory methods.
4. Assess the test’s usability in resource-limited clinics.
5. Evaluate the test’s stability under common field conditions.

---

---

What You Will Do Step by Step

---

1. Review current sepsis biomarkers and existing rapid tests.
2. Prototype the multiplex assay using simple materials.
3. Perform laboratory tests to compare results with established methods.
4. Test the assay’s performance under varied temperatures and handling.
5. Collect feedback from potential clinical users on ease of use.

hr>

---

Expected Outcome

Anticipated creation of a practical, validated, point?of?care test that can detect multiple sepsis signals quickly, with clear results, enabling earlier treatment and improved patient outcomes in resource-limited settings.