Development of SERS based ultra-sensitive, rapid, portable and field deployable platform for detection of pathogenic bacteria and Dengue virus
Primary Information
Domain
Healthcare
Project No.
6695
Sanction and Project Initiation
Sanction No: 6695
Sanction Date: 9/1/2017
Project Initiation date: 3/4/2017
Project Duration: 36
Partner Ministry/Agency/Industry
Ministry of Health and Family Welfare/ New Age Instruments & Materials Pvt. Ltd
Role of partner: Providing Funding
Industry partner's contribution: In development of the hand held device for Dengue diagnosis.
Principal Investigator
Dr. J.P. Singh
Indian Institute of Technology Delhi
Host Institute
Co-PIs
Prof. Prashant Mishra
Indian Institute of Technology Delhi
Dr. Neena Valecha
National Institute of Malaria Research
Dr. Deepali Savargaonkar
National Institute of Malaria Research
Scope and Objectives
The aim of the project is to develop a state-of-the-art SERS-based field-deployable handheld detection platform to detect early stage Dengue and its different serotypes as well as the infection by pathogenic bacteria.
Deliverables
The project will provide a new handheld, field deployable SERS platform having the capabilities of rapid on-chip specimen separation and detection of Dengue virus are used for point-of-care diagnostics. This will be a useful instrument in Health sector. The expected outcomes of the Research Plan are to (1) Fabricate the Ag nanorod arrays SERS substrates; (2) To develop an ingenious handheld Raman spectrometer; (3) Obtain the intrinsic SERS spectra of Dengue virus and pathogenic bacteria like Staphylococcus aureus and Escherichia coli and to build their spectral library into handheld SERS platform system; (4)Determine limit of detection for Dengue virus and pathogenic bacteria; (5)Obtain the SERS spectra of Dengue virus its serotypes from the blood serum samples of the infected patients and establish a quantitative calibration curve (SERS intensity versus virus concentration) for determining viral load.

Scientific Output
We have demonstrated SERS based diagnosis of Dengue using silver nanorods array. The array on glass substrate were fabricated by GLAD technique under high vacuum. SERS spectra were collected by hand held Raman spectrometer with 785 nm laser excitation. Enhancement factor of 107 has been obtained on Raman probe (BPE) using as-fabricated SERS substrates. Repeatability of Raman spectra has been achieved and statistically approved. Blood serum samples from different subjects (100) were collected from fever clinic of National Institute of Malaria Research (NIMR) New Delhi. All the samples were also dually verified by conventional methods PCR and ELISA. We have analyzed all the data and differentiated the NS1 positive, NS1 negative and healthy samples using a mathematical tool PCA employing PC1 and PC2 components. All the Raman bands were assigned to the respective constituents of blood serum. This rapid, portable, cost effective and user friendly technique renders early detection of Dengue with high sensitivity and reproducibility.

Results and outcome till date
We have collected the SERS spectra of Dengue positive, negative and healthy individual and created the library. For reproducibility of results, spectra were collected from about 100 individuals blood samples (infected as well as healthy subjects). Principal Component Analysis (PCA) is a used to reduce the dimensions and a large set of variables to a small set that still contains most of the information in the large set. All the data were analyzed and differentiated the NS1 positive, NS1 negative and healthy samples using a mathematical tool PCA employing PC1 and PC2 components. The data points clusters corresponding to positive, negative and healthy subjects clearly shown separated in plots. A portable hand held SERS device integrated with statistical software is under development. It may be the next diagnostic tool in near future at hospitals and field clinics.

Societal benefit and impact anticipated
SERS has been recognized as the powerful toll for detection of chemical and biomolecules at single molecule level. The laser light electric field coupled with plasmonic field results into the drastic enhancement if Raman single. The non-structural protein NS1 Antigen present in the infected blood after the onset of fever is used as the biomarker for the early detection. Conventional techniques for Dengue diagnosis are reverse transcriptase-polymerase chain reaction (RT-PCR) and Enzyme-linked immune sorbent assay (ELISA) kits. Present SERS based detection has potential to diagnose with in a minute at early stage of infection. It renders cost effective, rapid and field deployable solution for diseases diagnosis in hospitals and field clinics with high sensitivity and specificity.
Next steps
The next step is to assemble all the components into the a miniaturized hand held portable SERS based proposed device which will be dedicated for Dengue Diagnosis.
Publications and reports
Manuscript "Rapid and Field Deployable SERS Platform for Dengue Diagnosis using Hand Held Raman Spectrometer" is under review.
Patents
Nil
Scholars and Project Staff
1. Dr. Chandrashekhar Sharan Senior Project Scientist (July 2017 to Sept 2018)
2. Dr. Samir Kumar Project assistant (May 2017 to July 2017)
Challenges faced
As positive negative blood serum has almost similar SERS signal, so its very difficult to differentiate by only visualization. Therefore a statistical software is required for that, which needs a plenty of database and highly specific library for discrimination.
Financial Information
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Total sanction: Rs. 12216000.00
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Amount received: Rs. 7323000.00
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Amount utilised for Equipment: Rs. 949218.00
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Amount utilised for Manpower: Rs. 923723.00
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Amount utilised for Consumables: Rs. 389595.00
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Amount utilised for Contingency: Rs. 6340.00
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Amount utilised for Travel: Rs. 29466.00
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Amount utilised for Other Expenses: 0.00
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Amount utilised for Overheads: Rs. 807000.00
Equipment and facilities
1. Packaging unit to store the SERS substrates
2. Spectrometer, laser and fibers probes