Search results for "Biologically active"

Molecularly Imprinted Polymers as Useful Sorbents for Bioanalysis

2022

The determination of various active compounds in different types of biological samples attracts recently considerable attention. Unfortunately, the complexity of such sample matrices requires the application of multistage analytical procedures, which by many analysts is considered the most critical step in the whole analytical process. Sample preparation techniques dedicated to bioanalysis must ensure effective isolation and enrichment of various, often trace, amounts of analytes. Furthermore, the high selectivity of extraction of the target analytes, in relation to other interfering substances co-presented in the sample, is important in this case. Therefore, over the last two decades, the …

Polymer-based systems for controlled release and targeting of drugs

2019

The current need to find new advanced approaches to carry biologically active substances (conventional organic drugs, peptides, proteins (such as antibodies), and nucleic acid-based drugs (NABDs such as siRNA and miRNA)) in the body fluids, to realize targeted therapies and even personalized ones, goes hand in hand with research on the performance of new materials to better realize appropriate drug vectors [...]

An efficient synthesis of new fluorinated uracil derivatives.

2003

A series of potentially biologically active fluorinated uracil derivatives has been prepared in three steps from oxazolines and fluorinated nitriles with good chemical yields. Fustero Lardies, Santos, Santos.Fustero@uv.es ; Sanz Cervera, Juan Francisco, Juan.F.Sanz@uv.es ; Asensio Martinez, Amparo, Amparo.Asensio@uv.es

Chemical modification of halloysite nanotubes for controlled loading and release.

2020

Clay minerals have been used for medical purposes from ancient times. Among them, the halloysite nanotube, an aluminosilicate of the kaolin group, is an emerging nanomaterial which possesses peculiar chemical characteristics. By means of suitable modifications, such as supramolecular functionalization or covalent modifications, it is possible to obtain novel nanomaterials with tunable properties for several applications. In this context the covalent grafting of suitable organic moieties on the external surface or in the halloysite lumen has been exploited to improve the loading and release of several biologically active molecules. The resulting hybrid nanomaterials have been applied as drug…

Biologically active properties of plant extracts in cosmetic emulsions

2020

Abstract Describes biologically active properties waters plant extracts of domestic herbaceous species as a part cosmetic emulsion in this article. In particular, the antioxidant features related to vitamins, flavonoids, coloring, extractive and tannins were reported. The following research methods as qualitative analysis on groups of biologically active substances, thin-layer chromatography, titrimetry and photometry were used in the work. The ability of extracts to influence the physico-chemical, organoleptic and antioxidant properties of cosmetic emulsion samples was established. The ability of the extracts to exhibit antioxidant and prooxidant effects in cosmetic emulsion samples was de…

Biological activity studies on organotin(IV)n+ complexes and parent compounds

2006

This review summarized the literature and own data on the parent organotin(IV) compounds and complexes formed with biologically active ligands.

The Use of Silicones as Extractants of Biologically Active Substances from Vegetable Raw Materials

2021

Based on theoretical studies, the authors of this paper propose the use of cosmetic organosilicon polymers (commonly called silicones) for the extraction of a complex of biologically active substances contained in vegetable raw materials. It is important to note that the biological molecules do not interact with the organosilicones and, therefore, their properties are not altered after the extraction. In this work, we investigate the efficiency of several polyorganosiloxanes as extractants of vegetable raw materials (Calendula Officialis L. and Artemisia Absinthium L.) useful for the preparation of cosmetic emulsions. Specifically, the extraction studies were conducted by using polyorganosi…

1984

Different polymeric transport systems for biologically active substances are presented. In the past, most of the reviews on polymeric drugs dealt with pharmaca, fixed to conventional water-soluble polymers. Naturally occuring transport proteins with their complex features have recently been imitated by micellar solubilized polymers. Polymerized liposomes from polymerizable lipids can be regarded as vesicular solubilized polymers and are discussed as stable models for biomembranes. By insertion of glycolipids, these liposomes are rendered susceptible to specific recognition by proteins. When natural or cleavable synthetic lipids are incorporated into polymerizable membranes, phase-separation…