Decentralized vitamin C & D dual biosensor chip: Toward personalized immune system support

Abstract

Combating the ongoing COVID-19 pandemic has put the spotlight on nutritional support of the immune system through consumption of vitamins C and D. Accordingly, there are urgent demands for an effective on-the-spot multi-vitamin self-testing platform that monitors the levels of these immune-supporting micronutrients for guiding precision nutrition recommendations. Herein, we present a compact bioelectronic dual sensor chip aimed at frequent on-the-spot simultaneous monitoring of the salivary vitamin C and D dynamics. The new bioelectronic chip combines a new electrocatalytic vitamin C amperometric assay along with competitive vitamin D immunoassay on neighboring electrodes, to perform selective and cross-talk free detection of both vitamins in a 10-μL saliva sample within 25 min. The distinct vitamin C or D temporal profiles obtained for different individuals after vitamin supplementation indicate the potential of the new bioelectronic chip strategy for enhancing personalized nutrition towards guiding dietary interventions to meet individual nutrition needs and promote immune system health.

Label-Free Electrochemical Immunosensor Made with Tree-like Gold Dendrites for Monitoring 25-Hydroxyvitamin D3 Metabolite

“…The COVID-19 pandemic has highlighted the need for effective self-testing devices to monitor nutrients relevant to the immune system and to ensure protection against harmful diseases and pathogens . The intake of immune-supporting micronutrients such as vitamin D has been recommended for their benefits in absorption and regulation of calcium and phosphorus in the functioning of muscles and brain cells and to assist the immune system in fighting viruses and bacteria. − The 25-hydroxyvitamin D3 (25­(OH)­D3) metabolite is the form of vitamin D found in larger amounts in the body because it has a longer half-life (approximately 3 weeks); hence, the level of vitamin D of an individual is quantified through detection of 25­(OH)­D3. , According to clinical studies, an adequate concentration of vitamin D corresponds to values between 30 and 50 ng mL –1 25­(OH)­D3, while levels below 20 ng mL –1 and above 150 ng mL –1 are considered deficient and toxic, respectively …”

On‐Site Therapeutic Drug Monitoring of Paracetamol Analgesic in Non‐Invasively Collected Saliva for Personalized Medicine

“…Taking into account that precise analgesic dose depends on the metabolism of each individual and the health status, [5,6,11,16,17] the use of the paracetamol sensor as analytical tool was evaluated to check individual needs and guide adequate analgesic dosage. [11,17,24] The saliva biofluid was chosen for therapeutic drug monitoring of analgesic due to easy and simple access without stimulation and promising application for on-site decentralized analysis.…”

“…Taking into account that precise analgesic dose depends on the metabolism of each individual and the health status, [5,6,11,16,17] the use of the paracetamol sensor as analytical tool was evaluated to check individual needs and guide adequate analgesic dosage. [11,17,24] The saliva biofluid was chosen for therapeutic drug monitoring of analgesic due to easy and simple access without stimulation and promising application for on-site decentralized analysis. [11,25] The flexible sensor containing the pseudo-reference, counter, and working electrodes detects the target on the naturally secreted saliva to track the dynamic profile of paracetamol in human saliva after the administration of a single dose of analgesic oral tablet as shown in Figure 1.…”

“…[5,6,15] Saliva-based electrochemical sensors have paved the way for on-site TDM by tracking drug concentrations. [3] Sensors and biosensors have been used to detect Vitamin C, [11] antibiotics, [16] Vitamin C and D, [17] irinotecan and doxorubicin, [18] and Levodopa. [7] With biosensors, high specificity can be achieved; however, the issues with storage, stability, and high cost with enzymes and antibodies remain.…”

Protein-Induced Fluorescence Enhancement and Quenching in a Homogeneous DNA-Based Assay for Rapid Detection of Small-Molecule Drugs in Human Plasma

“…Most often, it is performed by liquid chromatography in combination with mass spectrometry techniques. − Alternative techniques for small-molecule analyte detection include enzyme-linked immunosorbent assay (ELISA); although this heterogeneous detection method is applied successfully for identification of small molecules, it is often less suitable for rapid quantification . Other types of heterogeneous assays for small-molecule quantification have been reported. − Homogeneous assays offer several advantages over heterogeneous assays such as ELISA, as there is no need for immobilization and washing steps, thus decreasing the turnaround time. Furthermore, they are more suitable for quantification of the analyte because there is no dependency on the quantity of immobilized species and on optical surface effects. , Homogeneous assays often employ aptamers, , DNA-binding proteins, , semisynthetic sensor proteins, , or antibodies including competitive antibody-based assays − where the readout is often based on the fluorescence or Förster resonance energy transfer (FRET).…”