All-Optical Planar Polymer Waveguide-Based Biosensor Chip Designed for Smartphone-Assisted Detection of Vitamin D
Sensors 2020, 20(23), 6771; https://doi.org/10.3390/s20236771
by Johanna-Gabriela Walter 1,Lourdes S. M. Alwis 2OrcID,Bernhard Roth 3,4OrcID and Kort Bremer 3,4,*
1 Institute of Technical Chemistry, Leibniz University of Hannover, 30167 Hannover, Germany
2 School of Engineering and the Built Environment, Edinburgh Napier University, Edinburgh EH10 5DT, UK
3 Cluster of Excellence PhoenixD, (Photonics, Optics, and Engineering—Innovation Across Disciplines), 30167 Hannover, Germany
4 Hannover Centre for Optical Technologies, Leibniz University of Hannover, 30167 Hannover, Germany
Did not notice anything in the paper about potential cost, accuracy, potential interferring components in blood, etc.
Tests for Vitamin D contains the following overview/opinion
- Fact: Many countries no longer pay for more than 1 (some not pay for even a single Vit D test)
They feel that Vit D testing is not needed except for a few conditions (Rickets, etc) Japan is an exception - Fact: Vit D tests are not very accurate
The best lab tests have accuracies and repeatabilities of +-5 ng
Low cost vitamin D Blood Tests - both in lab and at home
Many lab tests have accuracies and repeatabilities of +- 10 ng - or worse
Vitamin D deficiency of a group - 15% to 48% - Fact: Low-cost office/home Vit D tests are available around the world (not US as of 2018)
Low-cost 35 ng Y/N test by Nanospeed
Low-cost Vitamin D testers (two yes-no tests for 42 dollars) - 2023 Nanospeed
Quick, free, self test for deficiency - Fact: 3 major Vit D gene problems are not noticed by Vit D tests
~ 20% of people have poor Vit D genes
Hint that Vit D not getting to cells: Vit D related diseases run in your family
Another hint - you have one of the 40 diseases which are 2X more likely if have poor genes - Fact: A Vit D test will rarely (<1 in 1000) indicate that you are getting too much
- Opinion: If only getting a single test, wait till after supplementing with Vit D
3 months after starting a maintenance dose or 4 weeks after a loading dose
Download the PDF from VitaminDWiki
An all-optical plasmonic sensor platform designed for smartphones based on planar-optical waveguide structures integrated in a polymer chip is reported for the first time. To demonstrate the applicability of the sensor system for biosensing purposes, the detection of 25-hydroxyvitamin D (25OHD) in human serum samples using an AuNP-enhanced aptamer-based assay was demonstrated. With the aid of the developed assay sensitivity of 0.752 pixel/nM was achieved for 25OHD concentrations ranging from 0–100 nM. The waveguide structure of the sensor enables miniaturisation and parallelisation, thus, demonstrates the potential for simultaneous detection of various analytes including biomarkers. The entire optical arrangement can be integrated into a single polymer chip which allows for large scale and cost-efficient sensor fabrication. The broad utilization and access of smartphone electronics make the proposed design most attractive for its wider use in lab-on-chip applications.