The Helicobacter pylori (H. pylori) a highly propagated bacterium, considering that it infects more than half of world population. The H. pylori is the main cause of gastric adenocarcinoma, which leads it to be classified by International Agency for Research on Cancer (IARC) as class 1 human carcinogen. Regarding this, the bacterium eradication is the most indicated treatment, since the H. pylori is a harmful agent to its hosts. However, the antibiotics used for this treatment are susceptible to acid degradation in stomach environment, requesting high doses of them to achieve the expected bactericidal efficiency. In this context, the present work proposes to obtain a drug carrier made of Periodic Mesoporous Organosilica (PMO) matrix containing disulphide bridges in the pores structure, functionalized with vector and zwitterionic agents attached by covalent bond to silica surface. The presence of S-S bridges in silica pores provides to this support degradability under acid pH due to its reduction to thiol groups, thus, such phenomenon would lead the start of antibiotic release at stomach juice. The PMO is going to be functionalized with the CEACAM-1 antigen and a zwitterionic group. The CEACAM-1 antigen would act as a vector agent, since it can be a receptor of H. pylori in epithelial cells of stomach. In addition, the zwitterionic species would be used to guarantee the carrier biological activity as long as possible in biological media because it is capable of prevent the non-specific protein adsorption, also it could increase the carrier penetration in the stomach mucus. Therefore, this proposed carrier system would be able to adsorb high doses of antibiotic, protecting it from acid pH and delivering it close to H. pylori sites, and hence the increasing of antibiotic efficacy would lead to decreasing of drugs daily doses. In this way, this functionalized degradable PMO would be an alternative for H. pylori eradication treatment.
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