Mario ArandaChile

Chronic non-communicable diseases (CNCD) are responsible for 41 million of deaths per year, which represents 71% of all deaths worldwide. The most relevant ones are cardiovascular, cancer, diabetes, and chronic respiratory diseases accounting for around 80% of all CNCD deaths. These figures have increased the interest in searching bioactive molecules in natural sources with therapeutic potential over CNCD and neurodegenerative diseases. Several analytical techniques have been applied to detect this kind of molecules but each one has critical drawbacks. In this scenario, high performance thin layer chromatography (HPTLC) emerges as the technique of choice for bioactive molecules detection and identification because is unique features like the capacity of performing effect-directed analysis (bioassay) straight on the HPTLC plate and the direct coupling with mass spectrometry (MS). This presentation describes some examples of HPTLC/bioassay/MS approach to detect and identify bioactive molecules with therapeutic potential against CNCD and neurodegenerative diseases, in particular, those with inhibitory activity over key enzymes such as acetylcholinesterase, alpha-glucosidase and cyclooxygenase. In this respect, a new HPTLC-bioassay to detect cyclooxygenase inhibitors is presented, which is based on the oxidation of N,N,N,N-tetramethyl-p-phenyl diamine (TMPD) during the reduction of prostaglandin G2(PGG2) to prostaglandin H2(PGH2), reaction monitored at 590 nm. Microplate bioassay conditions, i.e., arachidonic acid and TMPD concentration and incubation time, were optimized via design of experiments and then transferred to HPTLC showing promising results such as inhibitors detection at ug level.

Acknowledgments
Authors want to thank to Chilean National Agency of Research and Development (ANID) for doctoral scholarship granted. This work was financially supported by projects FONDECYT Nº1211803 and REDES Nº180178.