Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
ACS Sens. 2023 Feb 24;8(2):534-542. doi: 10.1021/acssensors.2c01429. Epub 2023 Feb 8.
Multiplexed biomarker detection can play a critical role in reliable and comprehensive disease diagnosis and prediction of outcome. Enzyme-linked immunosorbent assay (ELISA) is the gold standard method for immunobinding-based biomarker detection. However, this is currently expensive, limited to centralized laboratories, and usually limited to the detection of a single biomarker at a time. We present a low-cost, smartphone-based portable biosensing platform for high-throughput, multiplexed, sensitive, and quantitative detection of biomarkers from single, low-volume drops (<1 μL) of clinical samples. Biomarker binding to spotted capture antigens is converted, via enzymatic metallization, to the localized surface deposition of amplified, dry-stable, silver metal spots whose darkness is proportional to biomarker concentration. A custom smartphone application is developed, which uses real-time computer vision to enable easy optical detection of the deposited metal spots and sensitive and reproducible quantification of the biomarkers. We demonstrate the use of this platform for high-throughput, multiplexed detection of multiple viral antigen-specific antibodies from convalescent COVID-19 patient serum as well as vaccine-elicited antibody responses from uninfected vaccine-recipient serum and show that distinct multiplexed antibody fingerprints are observed among them.
多重生物标志物检测在可靠和全面的疾病诊断以及对结果的预测中可以发挥关键作用。酶联免疫吸附测定（ELISA）是基于免疫结合的生物标志物检测的金标准方法。然而，这种方法目前成本高昂，仅限于集中式实验室，并且通常一次只能检测单个生物标志物。我们提出了一种低成本、基于智能手机的便携式生物传感平台，用于高通量、多重、灵敏和定量检测来自单个、低体积（<1 μL）临床样本的生物标志物。通过酶促金属化，将生物标志物与斑点捕获抗原的结合转化为局部表面沉积的放大、干燥稳定的银金属斑点，其暗度与生物标志物浓度成正比。开发了一个定制的智能手机应用程序，该程序使用实时计算机视觉来实现对沉积金属斑点的轻松光学检测，并对生物标志物进行敏感且可重复的定量。我们展示了该平台在高通量、多重检测来自恢复期 COVID-19 患者血清的多种病毒抗原特异性抗体以及未感染疫苗接受者血清中疫苗诱导的抗体反应方面的应用，并表明它们之间存在明显的多重抗体指纹。
