Self-aggregation in aqueous solution of amphiphilic cationic calix[4]arenes. Potential use as vectors and nanocarriers

• Published in: Journal of molecular liquids Vol. 304; p. 112724
• Main Authors: Ostos, Francisco J., Lebrón, José A., López-Cornejo, Pilar, López-López, Manuel, García-Calderón, Margarita, García-Calderón, Clara B., Rosado, Ivan V., Kalchenko, Vitaly I., Rodik, Roman V., Moyá, María Luisa
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.04.2020
• Subjects: Calixarenes; Compaction; ctDNA; Doxorubicin; Micelles; Vesicles; Vesicles; Compaction; Calixarenes; Doxorubicin; Micelles; ctDNA
• ISSN: 0167-7322; 1873-3166
• DOI: 10.1016/j.molliq.2020.112724

The self-aggregation of four amphiphilic cationic calix[4]arenes, CALIX, in aqueous solutions was investigated in this work. The nature of the polar group present at the upper rim as well as the length of the hydrophobic tails attached to the lower rim was varied. All the calixarenes present two critical aggregation concentrations, CAC1 and CAC2. For [CALIX] < CAC1 only micelles are present, within the range CAC1 < [CALIX] < CAC2 micelles as well as vesicles are observed, and for [CALIX] > CAC2 micelles and a wide distribution of vesicles were found. Cell viability experiments show that calixarene micelles and several of the calixarene vesicles investigated could be used as biocompatible nanocarriers. On this basis, the study of the interactions between the cationic calixarene aggregates (micelles and vesicles) and calf thymus DNA, ctDNA, were done and the results indicated that most of them strongly interact with the polynucleotide, inverting its charge. Micelles totally compact the ctDNA, while vesicles only partially cause conformational changes in the nucleic acid. Therefore, the CALIX micelles show potential as vectors in gene therapy. The encapsulation of the antineoplastic drug doxorubicin into the calixarene aggregates was also investigated. A high encapsulation efficiency was found for micelles and, specially, for vesicles. However, DOX-loaded calixarene vesicles present low stability at 37 °C, which is a serious restriction in their use as nanocarriers for this drug. The release of DOX from the calixarene micelles shows that they could lengthen the half-life of free doxorubicin in the body and, as a result, lower amounts of drug could be used in the cancer treatments diminishing the important side effects of DOX. The self-assembly of various cationic amphiphilic calix[4]arenes and their potential as vectors for genetic material and as nanocarriers for an antineoplastic drug were investigated. [Display omitted] •The self-aggregation of four cationic calix[4]arenes in aqueous solution was investigated.•The cytotoxicity of the calixarenes against several cell lines was examined.•The interaction of ctDNA with the calixarene micelles and vesicles was studied.•Calixarene micelles and vesicles encapsulate efficiently the drug doxorubicin.•The calixarene micelles present potential as drug nanocarriers.