Pratyasa

Sepsis moves in hours.
Pratyasa answers in real time.

A low-cost, handheld biosensor that detects bacterial endotoxin (LPS), a key sepsis biomarker, at the bedside. Down to ten attograms per millilitre.

प्रत्याशा Pratyasa, Sanskrit for hope. Granted patent IN 429867, Government of India.

Get in touch Watch it run
The handheld analyser, its display reading 'Concentration: 10 pg/ml', the disposable sensor chip held in clips beside it, and an Android phone mirroring the same reading over Bluetooth.
10 ag/mL
limit of detection
Granted 2023
protected to 2042
Whole blood
demonstrated in a real clinical sample

The test that can't come to the bedside

Sepsis demands intervention within hours, and septic shock still carries an in-hospital mortality rate above 40 %.

Yet the standard endotoxin test, the LAL assay, depends on horseshoe-crab blood, costs a great deal, and needs a trained technician in a laboratory. It can miss low concentrations of LPS in blood because of interference, return false positives from shifts in pH or temperature, and false negatives from limited sensitivity. None of it happens where the patient is.

Four steps, one handheld device

The detection pipeline Four stages: a functionalised sensor chip; the aptamer capturing LPS; a differential pulse voltammetry reading; and the result shown on the device and a paired phone. Sensor chip fCNT–Cu₂O + aptamer Capture LPS binds the aptamer Read DPV peak current 10 pg/mL Report display + Android app

Read the science

How small is ten attograms?

An attogram is a quintillionth of a gram. The sensor's floor sits at ten of them per millilitre, and it stays linear across nine orders of magnitude above that.

Detection range on a logarithmic mass scale A vertical logarithmic axis from milligrams per millilitre down to attograms per millilitre. The sensor's linear range runs from 10 nanograms per millilitre down to its detection limit of 10 attograms per millilitre, nine orders of magnitude. mg/mL µg/mL ng/mL pg/mL fg/mL ag/mL 10 ng/mL 10 ag/mL limit of detection nine orders of magnitude Detection range on a logarithmic mass scale A logarithmic axis from milligrams per millilitre down to attograms per millilitre. The sensor's linear range spans from 10 nanograms per millilitre down to 10 attograms per millilitre, nine orders of magnitude, ending at its detection limit. mg/mL µg/mL ng/mL pg/mL fg/mL ag/mL 10 ng/mL 10 ag/mL limit of detection linear range · nine orders of magnitude
Each labelled step is a thousandfold. From a milligram to an attogram is fifteen of them.

Measured, published, peer-reviewed

8.2%

relative standard deviation across five consecutive runs

71%

signal retained after 100 successive measurements

The complete prototype on the bench: analyser, sensor chip in its clips, and the paired phone, all showing the same reading.

18 × 11.5 × 5.5cm

handheld, 3D-printed analyser

Whole blood · Mayonnaise · Fruit juice

the three real sample types the sensor has been demonstrated in

All figures from Kuttoth, Pathak & Sandhyarani, Langmuir 2025, 41 (26), and its Supporting Information.

Real hardware, running

Not a render. The prototype reading a sample, with the result mirrored to the Android app over Bluetooth.

Two moments from a single run: the sample being applied, then the reading appearing. The processing wait between them is trimmed.

The evidence

A Low-Cost Portable Electrochemical Biosensor for Rapid Detection of Endotoxin and Method Thereof

Patent
IN 429867
Application
202241053140
Filed
16 September 2022
Granted
24 April 2023
Term
20 years, to 2042
Patentee
National Institute of Technology–Calicut
Inventors
Dr. N. Sandhyarani · Tushar Pathak · Haritha K · Dr. Arun R · Dr. M. K. Ravi Varma
View the certificate Verify on the Indian Patent Office register

A Point-of-Care Aptasensor for the Real-Time Detection of Sepsis Biomarker

Cover of Langmuir volume 41, issue 26, the issue in which the paper appears.

Kuttoth, H.; Pathak, T.; Sandhyarani, N. Langmuir 2025, 41 (26).

DOI 10.1021/acs.langmuir.5c00784

The paper cites this patent as reference 38. The published science and the granted claim point at each other.

Read the paper

Where it applies

The sensor has been demonstrated in three real sample types: whole blood, mayonnaise, and fruit juice.

Those results point at two settings. Bedside clinical testing, where a laboratory turnaround is too slow. And screening for bacterial contamination in food.

The LAL assay remains the pharmacopeial standard for compliance testing. This is a screening instrument, not a replacement for it.

About, and how to reach me

I'm Tushar Pathak, one of five inventors on patent IN 429867. I worked across the portable analyser's electronics and firmware, the Android application, sensor preparation, and the validation testing in blood and food samples.

The work was carried out in Dr. N. Sandhyarani's group at NIT Calicut. The patent is owned by the institute, so this page is a record of the work rather than an offer to license it. If you want to talk about where the technology could go, I'd like to hear from you.

Email the co-inventor Tushar_Pathak@outlook.com

Not an email client? Copy the address above. For anything touching licensing or assignment, the National Institute of Technology–Calicut is the patentee and the party to approach.

The Pratyasa presentation case, matte black with the name embossed in gold, in a gold frame.