A point-of-care ultrasensitive protein detection system
Lead Research Organisation:
Imperial College London
Department Name: Electrical and Electronic Engineering
Abstract
The aim of the project is to develop a Point-of-Care (POC) sensing system for ultrasensitive quantitative detection of proteins. Proteins are a large group of bio-molecules crucial in many clinical and healthcare applications. The current quantitative methods for protein detection are all lab-based. On the other side, the available POC devices, which although fast and inexpensive, are not sensitive enough and not quantitative. Therefore, the main objectives of this project are:
(a) to develop sensors for detecting proteins in very small concentrations
(b) to develop portable systems which can deliver quantitative measurements of protein concentrations
The starting point of the project is the novel aptamer-based technique for protein detection and quantification which has recently been developed in our group at the Centre for Bio-Inspired Technology, Dept. of Electrical and Electronic Engineering, Imperial College London. The key novelty of the project is the development of a new sensor based on standard CMOS technology which will incorporate the aptamer/DNA amplification to enable low sample volume detection of proteins.
The primary research questions to be answered in this project are:
1. What are the standardisation, optimisation and validation steps necessary to develop a label-free CMOS sensor capable of detecting 10-100pg/ml protein levels?
2. What are the technical and design challenges in implementing the sensor on a point-of-care electronic platform?
The proposed project will be executed in three main steps:
1. First, establishing a robust and efficient protocol for the development of an accessible, quick and reliable label-free test. The key task will be implementing a microchip-based detection technique, based on an integrated chemical sensor such as ISFET (Ion-Sensitive Field Effect Transistors).
2. The second step will be designing a platform for the sample preparation for the detection of the desired biomarker. Challenges in this step will be the use of raw biological samples such as saliva, which will enable the development of a non-invasive and user-friendly system.
3. Finally, the third step will be the design of an integrated electronic point-of-care platform able to quantify the desired proteins. This platform will be capable of running/controlling DNA amplification and data processing, with the aim of delivering quick and reliable results which can therefore find an easy placement in real-life applications.
This platform will allow a quantitative protein-based diagnostic tests for Point-of-Care Testing to provide improved healthcare in many applications and to transform the area of proteomics with the development of an affordable and ultrasensitive novel assay.
A key novelty of the platform is the design of an electronic chip capable of detecting free complementary DNA in a label-free and affordable system. This will facilitate translation of a lab-based proof-of-concept technique to a POC, small form factor product. Another novelty lies in developing a bio-chemical protocol with a microfluidic platform suitable for POC application. Further novelty will be the design of a platform with novel bio-signal/data processing capabilities, which will lead towards concretising the aptamer-based innovation into a POC test.
The applications of the technology are numerous, from disease testing to weight management. This system can benefit any application which requires a quick, accessible and reliable diagnostic tool. Therefore, this project fits very well within the EPSRC Clinical Technologies Ambition H3 (Healthcare Technologies) aimed at the development of novel technologies for sensing and diagnosis. Moreover, the development of this technology into a direct-to-consumer testing device has the potential to transform community health and care (Ambition H1) by offering an accessible and fast diagnostic system directly to patients.
(a) to develop sensors for detecting proteins in very small concentrations
(b) to develop portable systems which can deliver quantitative measurements of protein concentrations
The starting point of the project is the novel aptamer-based technique for protein detection and quantification which has recently been developed in our group at the Centre for Bio-Inspired Technology, Dept. of Electrical and Electronic Engineering, Imperial College London. The key novelty of the project is the development of a new sensor based on standard CMOS technology which will incorporate the aptamer/DNA amplification to enable low sample volume detection of proteins.
The primary research questions to be answered in this project are:
1. What are the standardisation, optimisation and validation steps necessary to develop a label-free CMOS sensor capable of detecting 10-100pg/ml protein levels?
2. What are the technical and design challenges in implementing the sensor on a point-of-care electronic platform?
The proposed project will be executed in three main steps:
1. First, establishing a robust and efficient protocol for the development of an accessible, quick and reliable label-free test. The key task will be implementing a microchip-based detection technique, based on an integrated chemical sensor such as ISFET (Ion-Sensitive Field Effect Transistors).
2. The second step will be designing a platform for the sample preparation for the detection of the desired biomarker. Challenges in this step will be the use of raw biological samples such as saliva, which will enable the development of a non-invasive and user-friendly system.
3. Finally, the third step will be the design of an integrated electronic point-of-care platform able to quantify the desired proteins. This platform will be capable of running/controlling DNA amplification and data processing, with the aim of delivering quick and reliable results which can therefore find an easy placement in real-life applications.
This platform will allow a quantitative protein-based diagnostic tests for Point-of-Care Testing to provide improved healthcare in many applications and to transform the area of proteomics with the development of an affordable and ultrasensitive novel assay.
A key novelty of the platform is the design of an electronic chip capable of detecting free complementary DNA in a label-free and affordable system. This will facilitate translation of a lab-based proof-of-concept technique to a POC, small form factor product. Another novelty lies in developing a bio-chemical protocol with a microfluidic platform suitable for POC application. Further novelty will be the design of a platform with novel bio-signal/data processing capabilities, which will lead towards concretising the aptamer-based innovation into a POC test.
The applications of the technology are numerous, from disease testing to weight management. This system can benefit any application which requires a quick, accessible and reliable diagnostic tool. Therefore, this project fits very well within the EPSRC Clinical Technologies Ambition H3 (Healthcare Technologies) aimed at the development of novel technologies for sensing and diagnosis. Moreover, the development of this technology into a direct-to-consumer testing device has the potential to transform community health and care (Ambition H1) by offering an accessible and fast diagnostic system directly to patients.
Organisations
People |
ORCID iD |
| Chris Toumazou (Primary Supervisor) | |
| Francesca Cavallo (Student) |
| Description | The main objectives of the project were to develop a sensor for detecting proteins in very small concentrations and to develop a portable system that can deliver quantitative measurements of protein concentrations. The first objective has been fully met: an aptasensor for the quantification of small protein concentrations through PCR amplification was developed, characterised and optimised. The aptasensor was developed for leptin, an important hormone involved in metabolism regulation, and validated on human leptin. For this aptasensor, a lowest limit of detection of 100 pg/mL within less than 2 hours was achieved, which significantly shortens the time-to-results of commercially available immunoassays for the quantification of proteins. The second objective was partially met. The high-level design of a point-of-care device for sensitive protein quantification based on the aforementioned aptasensor was developed, and the challenges and issues of implementing such a device were characterised. Furthermore, a custom data analysis algorithm to optimise the quantification of protein in the aptamer-based POC system was developed. However, the system has not been yet implemented and tested under real-life conditions. |
| Exploitation Route | The method for the aptasensor can be used by others wishing to develop a similar assay for other targets. The aptasensors should be easily adaptable to other target molecules, provided that an aptamer with high affinity for the target exists. The aptasensor can be used as the basis for devices based on detection methods other than optical, like RT-PCR, which we have used in this project. Moreover, other researchers may wish to develop sensors and/or platforms based on the aptamer-based assay developed as part of this project. |
| Sectors | Healthcare |