نشریه پژوهش های شیمیایی و نانو مواد
پیاپی 2 (تابستان 1401)

The interactions of Gold nanoclusters capped with glutathione (GSH-AuNCs) with bovine serum albumin (BSA) have been studied by fluorescence spectroscopic technique at pH 7.4. The quenching constants and binding parameters (binding constants and number of binding sites) were determined by fluorescence quenching method. The obtained results revealed the presence of a static type of quenching mechanism in the binding of GSH-AuNCs with BSA. Based on the thermodynamic parameters extracted from the fluorescence data, it was shown that binding of GSH-AuNCs to BSA was driven mainly by van der Waals and hydrogen bonding interactions. The displacement experiment shows that GSH-AuNCs can bind to the subdomain IIA (site I) of albumin.

Tuberculosis drug resistance is still one of the most important challenges in the treatment of this infectious disease, and therefore the discovery and development of new effective anti-tuberculosis drugs are always of interest to researchers. In this study, Quantitative structure – activity relationship (QSAR) analysis was applied on a series of imidazole[1,2-a] pyridinecarboxamide derivatives as anti-tuberculosis agents. The biological activity of the 18 derivatives were estimated by multiple linear regression and artificial neural network approaches. The four molecular descriptors (nCl, MATS8m, BELe4 and GATS8e) were selected by using stepwise multiple linear regression. The best results of artificial neural network were obtained with a 5-5-1 architecture trained with the feed forward backpropagation algorithm. An external test set containing 5 compounds for evaluating the model's predictive ability was used. The results showed that the artificial neural network approach provides better predictive power compared with multiple linear regression. According to the results of this study, electronegativity, atomic masses and molecular geometry have been found to be important factors controlling the anti-tuberculosis activity.

In the present paper, methane adsorption on the (8,0) single wall carbon nanotube decorated with Ag-Pd dimer is investigated using density functional theory. The results show that methane adsorption on the nanotube is an exothermic and physical process accompanied with the adsorption energy of -340 meV. The amount of adsorption energy indicates a significant increase in the adsorption energy of methane molecule on the decorated nanotube compared to pure one (-80 meV). The proposed structure before methane adsorption is a bipolar magnetic semiconductor with a small gap (-150 meV). On the other hand, methane adsorption energy is about twice the energy gap. This allows the carrier to be injected into the nanotube due to the heat of the reaction, followed by a change in conductivity. Therefore, the proposed structure has the potential to be used as a sensor based on reaction temperature and conductivity change.

Heterocyclic compounds play a very important role in both life and drug discovery, and in particular, a large number of synthetic molecules based on these structures have been reported with great potential in medicinal chemistry. Small polycyclic heterocycles are often found in pharmacophores and play an important role in drug discovery. Ketene aminals are multifunctional building blocks for the synthesis of all kinds of compounds. Bicyclic, tricyclic, and tetracyclic nitrogen-containing analogs with ketene aminal skeletons are widely available in natural and synthetic drugs. In recent years, significant progress has been made in the chemistry of ketene aminals. To understand and dominance the reaction properties of ketene aminals and the synthesis of other novel fused heterocycles, the investigation of ketene aminals is very important and necessary. This review covers relevant contributions with regard to the development and applications of ketene aminals, classified by reaction type and type of synthetic products.

Most of the chemical drugs that have been used recently have been designed, identified, and manufactured by organic-pharmacological chemists through various chemical reactions. Multicomponent reactions (MCRs) as an evolving process have played an effective role in the synthesis of various drug compounds and the production of various molecules and heterocycles. The chances of producing new drugs increase through different methods of synthesis and study of the biological properties of synthetic derivatives. In recent years, the synthesis of new drugs and the study of various variables to optimize the production process of various chemical compounds with diverse functional groups, which can be the source of various biological activities, has been a very significant topic in the field of organic-medicinal chemistry. So far, extensive research has been conducted on the synthesis of new heterocycles with the aim of drug studies. In this review article, an attempt has been made to compile and present a set of researches in the field of design and synthesis of heterocycles with medicinal properties, focusing on the use of multi-component reactions.

In recent decades, natural polymers, especially polysaccharides, have been used as carrier to deliver a wide range of therapeutic agents. Chitosan, the second most abundant natural polysaccharide after cellulose, is a biocompatible, biodegradable, hydrophilic, non-toxic, high bioavailability polymer with the ability to form films, gels, nanoparticles, microparticles, and granules. Chitosan is a linear polysaccharide obtained by deacetylation of chitin. Also, biodegradable chitosan in the human body is broken down into safe compounds (amino sugars) that are easily absorbed. Chitosan has hydroxyl and amine chemical functional groups that can be modified to achieve specific goals and turn it into a polymer with a wide range of potential applications. The aim of this paper is to provide insight into the potential applications of chitosan as a drug carrier. In the following, the use of chitosan to build deliverable sustainable delivery systems in other ways (oral, nasal, ocular, mucosal adhesion, buccal, and vaginal) is discussed. This report shows that research on chitosan-based systems containing different drugs for various therapeutic applications such as cancer treatment, gastrointestinal diseases, lung diseases, drug delivery to the brain and eye infections has increased in recent years.