A new clay-based material allows the controlled release of medicines

A new clay-based material allows the controlled release of medicines https://i1.wp.com/www.eresviral.com/wp-content/uploads/2018/11/Un-nuevo-material-a-base-de-arcilla-permite-la-liberación-controlada-de-medicamentos.jpg?fit=260%2C137&ssl=1

A new clay-based material allows the controlled release of medicines





A new clay-based material allows the controlled release of medicines


Clay minerals, which are already used in agriculture and in the manufacture of cosmetics, can also be applied in medicines such as anti-inflammatories and chemotherapeutics to improve their effects.



Brazilian scientists from the Chemistry Institute of the São Paulo State University (Unesp), in their campus in the town of Araraquara, and the Universidade de Franca (Unifran) developed a new material based on clay and a polymer. This structure allows to transport and release drugs slowly and gradually. In this way you can control the absorption of drugs in the body and prevent oscillations of the concentration in the bloodstream.



This new material was developed in the National Institute of Science and Technology (INCT) of Advanced Eco-efficient Technologies in Cement Products, one of the INCTs funded by the Scientific Research Support Foundation of the State of São Paulo - FAPESP in association with the Council National Scientific and Technological Development (CNPq) of Brazil in the state of São Paulo. The process related to obtaining the structure is described in a published article in the Applied Materials & Interfaces magazine of the American Chemical Society.



"We combine a commercial clay called sodium montmorillonite with a polymer gel at the nanometer scale [la milmillonésima parte del metro]. This is how we managed to obtain a material that allows a medication to be released gradually, at the most appropriate doses and rates, maintaining the ideal concentration in the bloodstream, "said Eduardo Molina, a professor at Unifran and one of the authors of the research.







They combine clay and a nanometer-scale polymer to create a structure that aims to gradually transport and release drugs. (Photo: Eduardo Molina)



The researchers incorporated sodium montmorillonite into a flexible and transparent matrix, composed of ethylene polyoxide (PEO). This material, with characteristics of hydrogel in the form of a rigid three-dimensional network, is capable of absorbing large volumes of water in its interstices without dissolving. That is why it is considered an excellent material for the controlled release of drugs.



But on its own, the hydrogel promotes the rapid release of a drug. It can also cause a problem called burst release - immediate release - when a high dose of an entry medicine is released and then maintained at a certain rate. "The hydrogel based solely on ethylene polioxide does not allow the slow and controlled release of the drug," said Molina, who also had the support of FAPESP.



Since it is known that clay is a waterproofing material, the researchers thought of trying to combine it with the hydrogel in order to verify if this material could constitute a barrier tending to allow a fine control of the quantity of the drug that is released.



To test this hypothesis, different concentrations of sodium montmorillonite were incorporated into a hybrid organic-inorganic hydrogel called siloxane-polyether or ureasil, through a process called sol-gel.



This method of preparation of materials is based on a series of chemical reactions in which the transformation of a liquid with nanometric particles in suspension - the "sun" - into a gel is specified.



The combination of both materials - the clay and the polymeric hydrogel - resulted in a nanocomposite to which diclofenac sodium was incorporated during the preparation of the material. This drug is an anti-inflammatory, orally administrable or injectable, which is used enough to relieve swellings and pains generated by arthritis, rheumatism, muscle injuries, surgeries or gout.



The analysis of the structures of the nanocomposites, made through the application of different characterization techniques, revealed that it was possible to clearly differentiate between the polymeric hydrogel, the clay and the drug in the materials.



In the performance tests of the material in the release of diclofenac, carried out in the laboratory in containers that simulate the biological conditions, it was found that the clay was essential to control the release form of the drug.



By adjusting the percentage of the clay used in the preparation of the nanocomposites, it was possible to avoid the release of a high dose of diclofenac sodium at the beginning, and allow the subsequent release to proceed slowly and at a constant and predictable rate.

"We managed to generate an effect called barrier diffusion, which allowed controlling the amount of drug released according to time," Molina explained.



The researchers found that depending on the amount of sodium montmorillonite incorporated into the hydrogel, the clay assumes the form of nanometric sheets homogeneously dispersed in the material. These nanometric clay lamellae acted as a physical barrier against the passage of water and drug molecules through the hydrogel channels.



"The clay lamellae formed a labyrinth inside the material that delayed the movement and gave a certain rhythm to the absorption of water and the release of diclofenac sodium," Molina said.



In the opinion of the researchers, this nanocomposite could be used to coat pills, for example, and thus act as a drug delivery system for prolonged treatments against arthritis, migraine and postoperative pain, among others. (Source: AGENCIA FAPESP / DICYT)

        .

  !function(f,b,e,v,n,t,s)

  {if(f.fbq)return;n=f.fbq=function(){n.callMethod?

  n.callMethod.apply(n,arguments):n.queue.push(arguments)};

  if(!f._fbq)f._fbq=n;n.push=n;n.loaded=!0;n.version='2.0';

  n.queue=[];t=b.createElement(e);t.async=!0;

  t.src=v;s=b.getElementsByTagName(e)[0];

  s.parentNode.insertBefore(t,s)}(window, document,'script',

  'https://connect.facebook.net/en_US/fbevents.js');

  fbq('init', '369524843414444');

  fbq('track', 'PageView');

    .


SOURCE LINK ERESVIRAL.COM 
https://www.beviral.online