The electrophotonic silicon biosensor

Abstract

The emergence of personalized and stratified medicine requires label-free, low-cost diagnostic technology capable of monitoring multiple disease biomarkers in parallel. Silicon photonic biosensors combine high-sensitivity analysis with scalable, low-cost manufacturing, but they tend to measure only a single biomarker and provide no information about their (bio)chemical activity. Here we introduce an electrochemical silicon photonic sensor capable of highly sensitive and multiparameter profiling of biomarkers. Our electrophotonic technology consists of microring resonators optimally n-doped to support high Q resonances alongside electrochemical processes in situ. The inclusion of electrochemical control enables site-selective immobilization of different biomolecules on individual microrings within a sensor array. The combination of photonic and electrochemical characterization also provides additional quantitative information and unique insight into chemical reactivity that is unavailable with photonic detection alone. By exploiting both the photonic and the electrical properties of silicon, the sensor opens new modalities for sensing on the microscale.

Detection of Brucella abortus by a platform functionalized with protein A and specific antibodies IgG

“…Isolation of the bacteria is the most specific diagnostic test, but the rate of isolation is generally low (Araj, 2010 The aim of this work was to design a platform for developing an immunosensor for direct Brucella detection on a surface coated with protein A to increase antibody-bacteria attachment. Silicon, a material used in design of optical, electrochemical, and mechanical sensors was chosen as the platform material (Jenison, La, Haeberli, Ostroff, & Polisky, 2001;Juan-Colás et al, 2016;Mendoza-Madrigal et al, 2013). The functionalization procedure was monitored by XPS at each step to assess the binding of the different chemical components to the silicon.…”

Methodologies for “Wiring” Redox Proteins/Enzymes to Electrode Surfaces

“…For UAA mutagenesis to serve as an immobilization methodology, functionalities complementary to those of the UAA must also be introduced to the electrode surface. Azide–alkyne cycloaddition click reactions therefore represent an attractive approach since methods for the introduction of these moieties onto electrode surfaces have been developed for other applications such as DNA sensor development . Should the use of a copper catalyst for activation of the cycloaddition reaction be undesirable, copper‐free reactions can be performed through the use of ring‐strained alkynes (Figure ) .…”

“…Azide-alkyne cycloaddition click reactions therefore represent an attractive approachs ince methods for the introductiono ft hese moieties onto electrode surfaces have been developed for other applications such as DNA sensor development. [219] Should the use of ac opper catalystf or activation of the cycloaddition reaction be undesirable, copper-free reactions can be performed through the use of ring-straineda lkynes (Figure14). [220] Surprisingly,b ased on the robust nature of this chemical ligation strategy, [221] the only known example using azide-alkyne UAA reactions for the site-specific linkage of ar edox protein or enzymet oa ne lectrode is the immobilization of the 4-azido-lphenylalanine (1,Figure14) containing laccase from Streptomyces coelicolor onto aM WCNT-coated electrode functionalized with complementary cyclooctyne containing linkers ( Figure 14).…”

OE-CAM: A Hybrid Opto-Electronic Content Addressable Memory

“…An OE-CAM cell is composed of one silicon based micro-ring resonator (MRR), a component that has gained foundry maturity and as such has been widely described in text books and research papers [33], since they provide a fundamentally important function utilized in several applications ranging from spectral filtering in optical links based on Wavelength Division Multiplexing (WDM) [34], [35] to sensors [36]. To summarize their working principle, when a bus waveguide is coupled to a microring resonator, by means of codirectional evanescent coupling, its transmission spectrum shows a dip near the ring's spectral resonances ( Fig.…”