Research & products

Sensing technology,
nano-biotechnology,
material science.

We work in the overlap of these three fields to provide pertinent solutions to healthcare. The lab's interests run across medical-device development, bio-nanosensors, nanodiagnostics, nanoanalytics, and the pre-formulation and formulation of smart materials.

Medical device development BioNanoSensors NanoDiagnostics NanoAnalytics Smart materials

ChemComm journal cover featuring the lab's work

01 — Area

Bio-Physio Sensors

We develop medical devices for diverse disease diagnostics and therapeutics. The devices are affordable to the mass population, easy to use and portable — so they can be used in remote or resource-limited settings.

Electrochemical immunosensors on screen-printed carbon electrodes
Impedimetric & voltammetric transduction for clinical serum samples
Paper-based disposable probes for naked-eye readout

Illustration of point-of-care testing at the bedside

02 — Area

Point-of-Care Techniques

The lab has expertise in developing lateral-flow immunoassays and the portable electronics needed for signal processing and analysis. Sensor-based colorimeters and fluorimeters have been developed in-house.

Lateral-flow immunoassays for rapid qualitative screening
Portable colorimeters and fluorimeters built and calibrated in the lab
Smartphone-coupled readouts that turn a phone camera into a detector

Scanning electron micrograph of electrochemically grown gold nano-dendroids showing first, second and third order branches

03 — Area

Nanobiotechnology

We synthesise nanoparticles including semiconductor nanocrystals — quantum dots. Biofunctionalising those particles improves their utility in building biosensors.

Quantum dots and semiconductor nanocrystals
Au nano-dendroids grown electrochemically for high surface area
Graphene-oxide nanocomposites and bioconjugation chemistry

Selected work

An immunosensor that matches the hospital bench.

Graphical abstract: screen-printed carbon electrode modified with gold nano-dendroids and graphene oxide detecting alkaline phosphatase in clinical serum

Biosensors & Bioelectronics

Clinically comparable impedimetric immunosensor for serum alkaline phosphatase detection based on electrochemically engineered Au-nano-Dendroids and graphene oxide nanocomposite

Kuldeep Mahato, Buddhadev Purohit, Ashutosh Kumar, Pranjal Chandra*

Read the abstract

We demonstrate label-free electrochemical impedance spectroscopy (EIS) based alkaline phosphatase (ALP) detection using gold nanoparticles (AuNPs), electrochemically engineered Au-nano-Dendroids, and graphene oxide (GO) nanocomposite. These nanomaterials were sequentially deposited onto the screen-printed carbon electrode (SPCE) and antibodies against ALP (anti-ALP) were immobilised using a carbodiimide bioconjugation process. The sensor probe has been characterised extensively using TEM, EDX, SAED, XRD, FE-SEM, FTIR, DIC and electrochemical techniques. The analytical performance of the fabricated biosensor was evaluated using EIS, where the linear dynamic range and limit of detection were 100–1000 U/L and 9.10 (±0.12) U/L respectively. The developed biosensor showed high selectivity towards ALP with negligible interference (k_sel ≪ 1; n = 3) from coexisting molecules. The sensor probe recovered ALP between 108.84% and 172.50% (n = 3) in human serum samples, and was used to estimate ALP in clinical serum samples where the level was found to be 83.15 U/L — comparable with the standard technique used in hospitals. Shelf life, stability and reproducibility have also been evaluated.

Read on ScienceDirect

Fabrication schematic of the paper-based sensor: 8 mm and 5 mm discs, O-ring, CATV lid and support assembly — Fabrication schematic for the paper-based sensor assembly.

Transmission electron micrograph of monodisperse quantum dots with a 10 nm scale bar — TEM of biofunctionalised semiconductor nanocrystals (quantum dots).

Products

From the bench to something you can hold.

Three device programmes taken from characterisation through to a usable kit, app or instrument.

Comparison strip: PC Lab reference row against the ALP milk testing kit row

AvailableDiagnostic kit

ALP Detection Kit

A paper-based kit for naked-eye detection of alkaline phosphatase — the milk-pasteurisation indicator. It reads against a printed reference strip, needs no instrument, and was the basis of a Gandhian Young Technological Innovation award.

AvailableAndroid application

ALP Analyzing Smartphone Application

The companion app for the detection kit. It captures the strip with the phone camera, compares up to five samples at once, and reports red-intensity deviation against the control as a histogram — turning a colour change into a number.

To be launchedInstrument

3D Printed Optical Sensing System

A compact, 3D-printed optical reader that houses the light path, sample stage and detector in a single printed enclosure — bringing benchtop optical sensing down to a portable footprint.

Research supported by