Hydrogels are materials that are commonly used in everyday objects such as contact lenses or diapers, in order to control humidity. However, chemical engineers at the University of Guadalajara (UdeG), in Mexico, developed a new technology based on thermosensitive nanoparticles (nano-hydrogels) to use these materials in the field of biomedicine, as an alternative to achieve controlled release of anticancer drugs.
Eduardo Mendizábal Mijares, professor at the Department of Chemistry, in the University of Guadalajara, said "we used nano-hydrogels loaded with drugs and injected them into the patient. With the characteristic that while passing through the bloodstream the drug is not detected nor attacked by the immune system, this due to their physical and chemical properties which make them compatible with the body."
The idea is that the drug, being within the nano-hydrogels, is transported directly to cancer cells where it can be released without damaging other parts of the body, because hydrogels offer the possibility of dosing a myriad of active substances on the site desired and can be administered as dry or swollen hydrogels by different routes: oral, nasal, buccal, rectal, transdermal, vaginal, ocular and parental. Drug release may come by a volume increase, changes in pH, or temperature.
The research, focused on developing thermosensitive nano-hydrogels which ,through a polymerization technique, mixes substances with different chemical and physical characteristics, achieving a chemical reaction and forming a set of small spheres called polymers.
The nano-hydrogels have shown very good characteristics of biocompatibility with the human organism, due to their physical properties, which make them resemble living tissues, especially by its high water content, its soft and elastic consistency, and its low interfacial tension which prevents them from absorbing proteins from body fluids.
By developing these materials absorbing large amounts of water without losing its shape was achieved, as well as the ability to retain heat at a temperature between 37 and 42 degrees Celcius. By combining emulsion polymerization and microemulsion the were able to synthesize structured hydrogels which present degrees of swelling and have better mechanical properties than conventional hydrogels, said the researcher.
These materials are used primarily in the biomedical area as diagnostic tools in membranes, coatings, microcapsules, implants for applications of short or long-range and systems of controlled drug release. Also the nano-hydrogels are used to regenerate tissue or mend fractures, serving as substrates for cell growth.
While molecular target drugs are already used against cancer, the novelty of the work is that materials such as nano-hydrogels can attack the cancer cells or tissues without damaging healthy body parts.
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