Doctors prescribe medicines, we take them. Neither the doctor nor the patient knows exactly how much of the drug is needed to cure the ailment, as this would differ from case to case. Today, to be on the safe side, doctors tend to slightly overdose the drug — because anything less than required cannot do the job well. But the excess drug, if any, mixes with the bloodstream and remains floating in the body, producing side-effects.
This problem will go away if the doctor can determine exactly how much drug is needed for each patient.
A group of researchers led by Dr Chandramouli Subramaniam, Associate Professor at the Department of Chemistry, IIT-Bombay, have devised a mobile app-based method to detect excess drugs in the bloodstream. It involves placing a blood sample on a film developed by the team and scanning it using the app, which then flashes a number.
How does this work?
Chemicals called fluorophores have molecules that absorb light and emit it at a higher wavelength. In higher concentrations they are bright and easy to detect. But low concentrations are difficult to detect.
Dr Subramaniam developed a coating by mixing carbon nanoparticles with a fluorophore. The carbon nano florets enhance the fluorophore’s emissions 1,000-fold. However, in the presence of a drug molecule, the intensity of the emissions falls. By comparing the intensities of the fluorophores in the vicinity of the drug molecules (3-5 nano-metres distance), you can tell how much residual drug molecule is floating in the bloodstream. Even a single molecule can be detected. The emissions can be detected using mobile apps such as Color Grab.
While Subramaniam’s team tested for perindopril erbumine, a drug used to treat blood pressure and prevent heart attack, the approach will work for any drug by using an appropriate fluorophore.