Ultra-sensitive detection of heparin via aPTT using plastic antibodies on QCM-D platform

Abstract

One of the challenges faced by today's clinics is unavailability of practical, precise and accurate determination of the most commonly used anti-coagulant ‘heparin’ in human blood/plasma in surgery. This is the first report of the application of a heparin imprinted thin film on a Quartz Crystal Microbalance with Dissipation (QCM-D) platform. Based on a novel, straight-forward and robust imprinting approach, a lowest volume consumption of 2 μL of real sample (of human plasma) has been demonstrated. This is a leap for launching spot testing for heparin sensing in laboratory practice. This approach could shorten the coagulation times to 48% and 45% for clinically important sensing range of heparin doses of 0.75 and 0.50 IU mL⁻¹ respectively and could improve precision 3-fold (n = 20 samples) compared to that of today's 'gold standard'. Activated partial thromboplastin time (aPTT) on the plastic antibodies based QCM-D platform for plasma with doses of heparin 0.75 IU mL⁻¹ and 0.50 IU mL⁻¹ yielded 6.5% and 5% lower %RSD respectively as compared to that of the ‘gold standard’. The present studies could provide a launch pad to laboratory methods for ultra-refining of point of care (POC) settings in the perspectives of coagulation time shortening, precision of the method and sample volume consumption.