Development and Evaluation of a Smartphone App-Based Rapid 25-Hydroxy Vitamin D Test

作者：SoYeong Han, Seung Hyun Kim, Myung‐Jin Kim, NaMi Park, Junnan Gu, S. J. Kim, S.Y. Lee, Jeongku Seo · 发表于：Diagnostics · 年份：2025 · DOI：10.3390/diagnostics15222916 · 被引用次数：2 · 研究领域：Biosensors and Analytical Detection、Biosimilars and Bioanalytical Methods、Vitamin D Research Studies

Objectives: The purpose of this study is to develop and verify a sandwich-type lateral flow immunoassay (LFA) integrated with a smartphone, enabling semi-quantitative 25-hydroxyvitamin D [25(OH)D] measurement including automated image analysis function, thereby establishing a reliable and accessible vitamin D evaluation system for point-of-care (POCT). Methods: A smartphone-based sandwich-type LFA was constructed, and 25(OH)D was measured semi-quantitatively. The system combined a customized test strip with an automatic image acquisition, calibration, and classification module integrated into an application dedicated to a smartphone. Analysis performance, reproducibility, and equivalence between sample types were comprehensively evaluated. Results: The developed analysis achieved a detection range of 5–100 ng/mL, and there were little interference and cross-reactivity for endogenous substances or structurally similar vitamin D derivatives. The image processing algorithm accurately classified the samples into three clinically important categories: deficiency (<20 ng/mL), insufficient (20–30 ng/mL), and sufficient (>30 ng/mL). Cross-platform testing between Android and iOS devices showed excellent reproducibility (r = 0.99, R2 = 0.9967). Comparative analysis with the Atellica IM 1600 analyzer showed a high degree of agreement between 97.0% category consensus and κ = 0.951 (r = 0.99, R2 ≥ 0.98). Comparative tests between serum and capillary samples also confirmed a 100% cl...