Singapore inventor creates portable PCR test kit that can detect COVID-19 in 5 minutes

The Quiz PCR biochip and the Poche USB dongle, which controls some of the processes on the biochip. PHOTO: CELL ID via The Straits Times

SINGAPORE — Singaporean medical technology company Cell ID has created a portable polymerase chain reaction (PCR) test kit that can confirm if someone has Covid-19 in five minutes.

Chief technology officer Xander Sim said those administering the test would not need specialized training or a laboratory to produce results.

The nasal swab test is run through an app on a laptop, and requires less than two hours of training to operate.

However, the operator must be trained to take nasal swab samples.

“This way, when passengers come in at an airport, you only need to hold them for a short time before you get a result,” Mr Sim said on Monday (Nov 30) at a virtual press conference to announce the Quiz PCR Biochip test kit.

The “gold standard” for Covid-19 testing is the PCR test.

However, PCR tests require highly specialized labs and technicians to run the tests, and liquid reagents that must be kept refrigerated.

It can also take days to return the results.

Increasingly, as Singapore seeks to reopen its economy further, it has been tapping antigen rapid tests (ARTs), which can produce results in under 30 minutes.

But ARTs have lower sensitivity and specificity, and may carry a higher risk of false positives and false negatives.

Mr Sim said Cell ID’s PCR test can confirm a positive case in five minutes, and a negative case in under an hour. Running a test longer ensures there are no false negative results.

“The aim was to develop a device that is accurate, without any compromise in the test result, but at a very affordable price… a test kit that someone in the third world can use as well,” added Mr Sim.

The Quiz PCR Biochip has 97 per cent to 100 per cent sensitivity to Covid-19, and a specificity of 100 per cent.

This is comparable to conventional PCR tests, unlike other rapid tests that are fast but have less specificity and sensitivity.

With the Quiz PCR Biochip, the nasal swab sample is first mixed in a solution.

A very small quantity of the resultant mix – 10 micrometers – is then combined with another solution.

This ensures that the virus’ genetic signature is in sufficiently high quantities for it to be detected.

The mixture is then put into one of two test wells on the Quiz PCR Biochip, which itself is smaller than a credit card.

The chip is then plugged into a special USB dongle, dubbed “Poche”, and connected to a laptop for the test to begin. The results can be monitored in real time.

Gene segments of the virus consume reagents in the solution as the virus multiplies, showing up as a dip in the graph that is displayed on the laptop screen.

Depending on the number of USB ports available, multiple tests can be run at the same time.

The chip, which is disposed off after each test, is able to process the sample faster than the machines in a laboratory because the machines are programmed to examine all its chambers, even when there is only a single sample.

Furthermore, conventional PCR tests must be run in batches and the process cannot be interrupted.

So if a PCR machine has capacity for 96 samples, but only 10 samples are put in the machine, any sample that arrives later will have to wait until the first 10 samples have completed the testing process.

This can result in a backlog.

Cell ID’s test apparatus allows for samples to be tested individually, without interrupting the testing of any other samples, said Mr Sim. He added that conventional PCR tests also require samples to be collected and transported to a lab compared to Cell ID’s tests, which are conducted at the point where the samples are collected.

Trained in engineering

Mr Sim, 56, spent more than three decades in the engineering and manufacturing fields before switching in 2013 to developing medical diagnostic tools, despite having no background in biology.

He invented Quiz PCR Biochip in 2015 and by 2018, had it configured for HIV tests, although it was never used.

Mr Sim said he had to endure years of failed prototypes, which also saw him suffer two strokes. It left him temporarily blind and with a weak left leg.

“(I told God) I don’t need to live for 100 years, just give me a little more time so I can finish my work and my mission,” Mr Sim recalled at a press conference on Monday.

In April, amid the circuit breaker, Cell ID developed a reagent that allowed it to be used to test for Covid-19.

Mr Sim said that it is difficult to predict how much testing will cost when using Cell ID’s chip, as it would depend on factors such as the overhead costs incurred by the testing agency.

He said it currently costs less than US$50 (S$67) to produce one of the chips, but this is expected to fall with economies of scale.

Tested at dorms

The Quiz PCR Biochip was tested at the S11 dormitory and the Expo Community Care Facility earlier this year, in collaboration with staff from Sengkang General Hospital and Woodlands Health Campus.

Out of the 215 people who were tested using the chips, 27 positive cases were detected.

Mr Sim recalled: “The first result came back positive within seven minutes. We were overwhelmed.”

He said everyone at the command centre was surprised an accurate Covid-19 test could be done on-site.

“I nearly teared up,” he added.

The tests were also verified at a third-party lab in Switzerland in November, where it was discovered that the biochip could detect the coronavirus equally well in saliva and nasal swab specimens.

Mr Sim said he is excited about this, as saliva tests are faster and require less equipment than nasal swab tests.

They are also not as uncomfortable for the patient.

He is currently waiting for regulatory approval from the authorities, such as the United States’ Food and Drug Administration and Singapore’s Health Sciences Authority, for the kit to be used.

Mr Sim said: “My hope is that the test can be deployed globally and that it will be useful in helping countries to open up safely again.

“That is my greatest hope.”