Qualitative and quantitative detection of biomarkers in biological samples (blood, serum, urine and saliva) could in theory indicate nutrient deficiencies, elevation of specific biomolecules and existence of infectious or foreign particles in a physiological system. CKDu is one of the burning health issues in Sri Lanka whose causative origins are still not fully agreed upon. Therefore, being able to diagnose the onset of the disease at an early stage is of paramount importance to manage the symptoms and ensure the recovery of patients. In this study, we first constructed a Raman spectroscopy setup that can be used to conduct surface enhanced Raman scattering (SERS) spectroscopy where highly sensitive biomarker detection can be done. The research-grade Raman spectrophotometer built with off-the-shelf optomechanical components has ensured the construction of a low-cost setup without compromising the device performance. This design has almost all the standard features with flexibility in further add-on features to improve device characteristics. The overall cost of construction of the spectrophotometer was approximately USD 86,000 relative to the prohibitively high cost of a typical (&gt;USD 250,000) commercially available Raman spectrophotometer with approximately similar features. The Andor KYMERA-328i-A spectrograph used possesses reflective type Czerny-Turner geometry ruled diffraction gratings (of either 600 l/mm or 1200 l/mm) which is able to resolve spectra down to 0.1 nm and 1600 × 200 back-illuminated electron multiplication (EM) CCD for low light detection (with 16 μm pixel size), which also contains a 16-bit ADC that can be operated at 3 MHz with low read noise = 39.8<i>e</i>. Maximum signal count of 65535 was achieved while the noise margin appears around 300 counts. To conduct SERS detection of specific biomarkers gold nanoparticles have been synthesized which are then planned to be conjugated with the capture molecules (specific antibodies). We believe that this is an excellent approach to conduct biomarker detection and diagnose diseases at their onset with a modest budget.

Designing and construction of a custom-built Raman spectrophotometer at a modest budget to detect Chronic Kidney Disease of unknown etiology (CKDu) related biomarkers using SERS substrates

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.