Ultrarobust Biochips with Metal–Organic Framework Coating for Point-of-Care Diagnosis

Abstract

Most biosensors relying on antibodies as recognition elements fail in harsh environment conditions such as elevated temperatures, organic solvents or proteases because of antibody denaturation, and require strict storage conditions with defined shelf-life, thus limiting their applications in point-of-care and resource-limited settings. Here, a metal-organic framework (MOF) encapsulation is utilized to preserve the biofunctionality of antibodies conjugated to nanotransducers. This study investigates several parameters of MOF coating (including growth time, surface morphology, thickness and precursor concentrations) that determine the preservation efficacy against different protein denaturing conditions in both dry and wet environments. A plasmonic biosensor based on gold nanorods as the nanotransducers is employed as a model biodiagnostic platform. The preservation efficacy attained through MOF encapsulation is compared to two other commonly employed materials (sucrose and silk fibroin). The results show that MOF coating outperforms sucrose and silk fibroin coatings under several harsh conditions including high temperature (80 °C), dimethylformamide and protease solution, owing to complete encapsulation, stability in wet environment and ease of removal at point-of-use by the MOF. We believe this study will broaden the applicability of this universal approach for preserving different types of on-chip biodiagnostic reagents and biosensors/bioassays, thus extending the benefits of advanced diagnostic technologies in resource-limited settings.

Metal–Organic Framework Coating for the Preservation of Silver Nanowire Surface‐Enhanced Raman Scattering Platform

“…After coating with ZIF‐8, new reflections, marked with red circles, appeared (red spectrum in Figure f). These XRD patterns correspond to the simulated ZIF‐8 peaks of the (011), (002), (112), and (222) planes (green spectrum in Figure f) and agree well with the previously reported literature . These results suggest that ZIF‐8 was successfully coated on the Ag‐NOF platforms.…”

“…Figure b is a scanning electron microscope (SEM) image of the bare Ag‐NOF platform, and Figure c,d shows SEM images of ZIF‐8‐coated Ag‐NOF structures treated for 20 min and 8 h, respectively. As shown in Figure d, thick ZIF‐8 layers were formed after reaction for 8 h. We also tried to remove the MOF layers from the Ag‐NOF structures and verified that the coated MOF layers can be removed by rinsing with a slightly acidic aqueous solution (Figure S1, Supporting Information) . To optimize the MOF removal buffer, deionized (DI) water and buffers were tested in various pH conditions (Figure S2, Supporting Information).…”

“…Metal–organic frameworks (MOFs), composed of metal nodes and organic linkers, have been considered promising materials in wide applications such as gas separation, catalysts, drug delivery, and chemical sensing due to their outstanding properties, including high surface area, tunable porosity, organic functionality, stable shelf life, and high thermal stability . Recently, Falcaro and Tsung's group reported that the MOF encapsulation of biomolecules is possible under biocompatible conditions, and Singamaneni's group demonstrated that MOFs can be used to preserve the recognition capability of antibodies under harsh conditions . Zheng et al reported the general synthetic method of Metal@MOF hybrid structures and investigated the transport of guest molecules through the MOF by SERS observation .…”

Metal–Organic‐Framework‐Engineered Enzyme‐Mimetic Catalysts

“…[191] While the MOF-engineered Enz-Cats have abundant reaction sites, with better conductivity and higher mechanical stability, they could become more dramatic and beneficial alternative biosensors with enhanced sensitivities and high detection limits. [192] Based on this, the MOF-engineered Enz-Cats have been successfully utilized as novel biosensors for the detection of ions, small molecules, nucleic acids, proteins, etc. [193] For instance, as shown in Figure 15, the Zhu group utilized a Fe-MOF (Fe-MIL-88B-NH 2 ) with outstanding biocompatibility, remarkable POD-like activity, and an optimal stability for the immobilization of GOx through an amidation reaction.…”

Biochips, aplicaciones convencionales e innovación: Una revisión documental

“…Los resultados muestran que el recubrimiento supera los otros revestimientos bajo varias condiciones adversas como temperatura a 80°C, y también presentan una estabilidad en ambientes húmedos. Los autores consideran que este estudio ampliará la forma de preservar diferentes tipos de reactivos en chips y biosensores [29]. Se presentan algunas técnicas de diseño asistido por computador (CAD) como son: Difusión de Direccionamiento-Electrodo, Pin-Count y técnicas de enrutamiento para el diseño de biochips.…”