Estudi de l’efectivitat bactericida de nanopartícules de plata modificades: efecte de la protein corona


Magallon Mosella, Maria


Bacterial infections are a major cause of chronic infections and mortality. Antibiotics have been the treatment method of choice for bacterial infections because of their cost-effectiveness and good and potent results. Several studies have provided direct evidence that the widespread use and abuse of antibiotics has led to the emergence of multi-resistant bacterial strains and that bacterial resistance can develop against each of the mechanisms of action of antibiotics.
This has led to the need for a new strategy, such as silver nanoparticles. Most antibiotic resistance mechanisms are irrelevant for nanoparticles because their mechanisms of action have different targets. Nanoparticles do not act by a single mechanism but rather the antibacterial action comes from a combination of several pathways acting together. This leads to the expectation that nanoparticles are less likely to promote resistance in bacteria than antibiotics. Therefore, attention has focused on new materials based on NPs with antibacterial activity. However, they present a problem in that they have a low interaction with bacteria. It is for this reason that in this work a study was carried out to understand, control and optimize the physicochemical parameters of the nanoparticles, as well as to modulate their surface as it plays an important role in their biological response, toxicity, and stability.
Experimentally, silver nanoparticles with antimicrobial properties were successfully synthesized by Tollens synthesis, which were subsequently coated with an albumin and L-cysteine corona and a yeast extract corona. The formation of the protein corona clearly improved the stability of the silver nanoparticles, and this allowed us to see what effect the nanoparticle with the protein corona would have on toxicity and how these protein coronas affect the interaction between the nanoparticle and the bacteria in in vitro assays with mainly Escherichia coli and UPEC.
Finally, the formation of the protein corona showed an improvement in the bactericidal effect and in the stability of the synthesized nanoparticles in a biological medium, which may end up demonstrating that silver nanoparticles, if their surface is modulated and the key physicochemical properties are controlled, are a very promising and potent strategy.



Teixidó Bartés, Robert


IQS SE - Undergraduate Program in Biotechnology