Since ancient, human have been fighting against diseases for a better chance of survival. With limited knowledge of diseases, people in the past learnt by trial and error and developed treatments from herbs and folklores. Nowadays with advanced science and technology, diagnosis methods and treatments are developed in more scientific approaches. For instance, based on the findings in pathogens infection mechanisms and drug-biomolecule interactions, chemists are now able to design and synthesize drugs with specific reactions to treat and prevent targeted diseases. Together with the modern medical diagnostic techniques which allow early diagnosis of diseases, effective and timely treatments are more possible, so as a higher survival rate and a prolonged life span for mankind.
Drug delivery refers to the method and approach to bring the pharmaceutical compounds precisely to the targeted sites to take effect, for instance, crosslinking with DNA leading to DNA damage and induce subsequent cell apoptosis. However, the deactivation of drugs may take place before the drugs molecules reach the target sites as unintended reactions could occur. To make matters worse, undesired reactions can lead to side effects, damaging healthy cells and harm the patients. It is therefore necessary to deliver the drug right at the point.
Recent research directions
Lipid-based polymers as capsules to bypass the liver link
Researchers developed a new way for delivering RNA drugs to the lungs with lipid-based polymers. One of the challenges in delivering RNA drugs is that they might be degraded by the liver. With the aid of these lipid-based polymers, RNA code was able to bypass the liver and delivered into the lungs in animal tests.
A scalable method to isolate exosomes from unpasteurized cow's milk was reported. Exosomes are biological capsules in nanoscale that are known to be stable enough to withstand pH and temperature change within the gut and the bloodstream. With this new method, it is hoped that exosomes can be extracted from milk and used in drug delivery.
Traceable drug delivery and controlled activation of drugs link
By combining the drugs for chemotherapy and photodynamic therapy with fluorescent dye molecules in a nanotube, researchers reported an effective cancer treatment with an even lower dose. The fluorescent dye allows doctors to track the position of the nanotubes. When the nanotubes reach the targeted site, the drug for photodynamic therapy is activated by light and releases reactive oxygen species to kill the tumor cells.
Thermo-responsive protein hydrogels for drug delivery link
Researchers developed a new way of delivering drugs with biocompatible, protein-based hydrogel. Such hydrogel self-assembles into a gel-like structure at low temperatures, and can provide a sustained medication release for over two weeks in the body. Wider applications are envisioned with future work focusing on fine-tuning the thermosensitivity of hydrogels.
Detection and diagnostics
Thanks to medical advances, cancers and many diseases are no longer incurable, and there is a greater chance to be cured if spotted in early stage. With the help of specially designed markers and more sophisticated spectrometers, it is hoped that inspection can be made more affordable, reliable, and convenient.
Recent research directions
Thin-film chemosensor for detection of neopterin link
A high concentration of neopterin in the body is correlated to neoplastic diseases. Based on this idea, researchers prepared a thin-film chemosensor by molecular imprinting such that it can specifically bind with neopterin.
Real-time biosensor for tracking phenylalanine levels in blood link Researchers fabricated an electrochemical sensor by chemically attaching a gold electrode to one end of an aptamer which captures phenylalanine and methylene blue to the other end. When the aptamer captures a phenylalanine molecule, a structural change is induced, causing the methylene blue to move closer to the gold electrode and making electron transfer possible. The electron transfer from methylene blue to the gold electrode is then recorded as an electrical signal. By measuring the intensity of the current produced, the concentration of phenylalanine in blood can be determined.
Test for malaria using cheap and printable paper stripslink
Researchers designed ionic probes to tag specific antibodies and then incorporated the ionic probes into paper strips. These probes allow ultra-sensitive detection with a hand-held mass spectrometer. Unlike enzymes being coated on conventional paper-based medical diagnostics, the ionic probes are not sensitive to temperature, humidity, and light. Theoretically, it is reported that this technique is applicable to all diseases for which the human body produces antibodies.