Ensuring vaccine cold chain integrity - A rapid and low-cost test for identifying heat-exposed sucrose-containing vaccines

Sep 30, 2026

Maintaining cold-chain integrity is vital for vaccines to remain within recommended temperature limits during routine storage and transportation, preserving stability and efficacy while preventing degradation. A rapid, low-cost approach uses simple glucose assays to detect heat-exposed, sucrose-containing vaccines by leveraging sucrose’s gradual conversion to glucose under elevated temperatures. Bioluminescent and colorimetric assays, alongside a clinical biochemical analyser for urine samples, quantify glucose increases that correlate with potency loss after 37°C and 45°C heat exposure.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages11

Reading Time28 min

AccessFree to download

1. Introduction

Cold-chain integrity challenges and detection gap

International Journal of Pharmaceutics: X 11 (2026) 100467 Contents lists available at ScienceDirect International Journal of Pharmaceutics: X journal [homepage:](homepage: www.sciencedirect.com/journal/international-journal-of-pharmaceutics-x)[ www.sciencedirect.com/journal/international-journal-of-pharmaceutics-x](homepage: www.sciencedirect.com/journal/international-journal-of-pharmaceutics-x) Ensuring vaccine cold chain integrity: A rapid and low-cost test for identifying heat-exposed sucrose-containing vaccines Benediktus Yohan Armana,b,1, Andrea Magric, Matteo N. Barbagliaa,b,c, Lawrence Petherbridge c, Jennifer Brook d, Tehmina Bharuchaa,b, Isabelle Leggee, John Walsby-Ticklee, Michael Deats f,g,h, Sneha Banerjee i, Sara Moscai, Rajender Jena j, Dnyanesh S. Ranade j, Shrikrishna R. Chunekarj, Kundan D. Patilj, Sunil Gairolaj, Hamid A. Merchant k, Robert Stokes l, Rutendo Kuwanam, Alexandrine Maesm, Tim James d, Catherine Green c, James McCullaghe, Pavel Matousekf,i, C´eline Caillet f,g,h, Paul N. Newton f,g,h,*, Nicole Zitzmanna,b, Bevin Gangadharana,b,* a Department of Biochemistry, University of Oxford, OX1 3QU Oxford, UK b Kavli Institute for Nanoscience Discovery, University of Oxford, OX1 3QU Oxford, UK c Clinical BioManufacturing Facility, Nuffield Department of Medicine, University of Oxford, OX3 7JT Oxford, UK d Department of Clinical Biochemistry, Oxford University Hospitals NHS Foundation Trust, OX3 9DU Oxford, UK e Department of Chemistry, University of Oxford, OX1 3TA Oxford, UK f Medicine Quality Research Group, NDM Centre for Global Health Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7LG, UK g Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand h Infectious Diseases Data Observatory, Centre of Tropical Medicine & Global Health, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7LG, UKi Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, UKRI, Harwell Campus, OX11 0QX, UK j Serum Institute of India Pvt. Ltd., 212/2, Hadapsar, Pune 411028, India k Department of Bioscience, School of Health, Sport and Bioscience, University of East London, Water Lane, London E15 4LZ, UK l Agilent Technologies LDA UK, Becquerel Avenue, Didcot OX11 0RA, UK m Regulation and Safety Unit, Regulation and Prequalification Department, Access to Medicines and Health Products Division, World Health Organization (WHO), Geneva, Switzerland A R T I C L E I N F O Keywords: Vaccine Potency Substandard Sucrose Glucose Cold chain Supply chain Degradation A B S T R A C T Maintaining cold-chain integrity is vital for vaccines to ensure that they remain within the recommended temperature limits during routine storage and transportation. This ensures vaccine stability, efficacy, and avoids degradation. Here, we propose rapid and low-cost tests based on simple glucose assays to detect heat-exposed degraded sucrose-containing vaccines through sucrose’s inherent gradual conversion to glucose when exposed to elevated temperatures. Bioluminescent and colorimetric assays and a clinical biochemical analyser for urine samples could successfully determine effects of heat exposure on vaccines by detecting a significant increase in glucose levels. We show that this increase in glucose also correlates with the loss of vaccine potency. When vaccines were incubated at 37 and 45 ◦ C, the bioluminescent assay was able to detect an increase in glucose levels from 12 h of heat exposure. The biochemical analyser could successfully detect increased glucose levels ina COVID-19 vaccine which had been exposed to 37 and 45 ◦ C. Most importantly, the colorimetric assay has the advantage of producing a colour change visually upon simply mixing the vaccine with a reagent without the need for a plate reader or any other sophisticated devices. To our knowledge, this is the first si

FAQs

Why is cold-chain integrity critical for vaccines?

Cold-chain integrity ensures vaccines stay within recommended temperature limits during storage and transport, which preserves stability and efficacy and helps avoid degradation.

How does the proposed test identify heat-exposed sucrose-containing vaccines?

The test detects glucose generated when sucrose gradually converts to glucose under elevated temperatures, using glucose-based bioluminescent and colorimetric assays and urine biochemical analysis.

What evidence links the glucose increase to vaccine potency loss?

The document reports that glucose increases detected after heat exposure (including incubation at 37°C and 45°C) correlate with loss of vaccine potency.

Sep 30, 2026

Uploaded by Olivia Brown