Wyniki wyszukiwania - BazTech

1

Sieci metalo-organiczne typu MOF jako przykład mateiałów wykorzystywanych w ukierunkowanej terapii przeciwnowotworowej

Samaszko-Fiertek Justyna, Khalatyan Alina, Dmochowska Barbara, Ślusarz Rafał, Madaj Janusz

Wiadomości Chemiczne

|

2023

|

[Z] 77, 1-2

35--53

EN

MOF materials (metal-organic frameworks) are a relatively organic-inorganic (hybrid) materials. Due to very good adsorption properties, large specific surfaces and large pore volumes, these compounds are quite intensively studied, and the number of organic-inorganic hybrids obtained is growing year by year. Most MOF compounds are crystalline two- or three-dimensional organometallic structures. They are an example of hybrid materials that are made of both inorganic and organic component. The inorganic part is represented by metal ions/clusters, while the organic skeleton contains neutral or charged organic linkers [1-3]. The most common metal cations included in organometallic lattices are: Zn2+, Cu2+, Cr3+, Al3+ and Mg 2+. Organic ligands can be neutral, positively or negatively charged, but they must be primarily electron pair donors, which means that they have nitrogen or oxygen-containing functional groups in their structure. Ligands’ role is to stitch these building units together to create extended framework structures, while metal ions provide structural integrity and durability. These materials have a well-developed specific surface and a large pore volume (570-3800 m2/g). Thanks to the presence of coordination bonds in the structure, the skeletons of organometallic networks are flexible. Based on literature data, several methods of cancer treatment using MOFs are distinguished, e.g.: using passive targeting, active targeting, physicochemical targeting, and in a particular case using all three strategies (Fig. 2, Table 1) [12,13]. The ongoing work on the modification of the synthesized MOF structures based on zinc ions allows the preparing various types of cancer drugs based on their durability and high porosity. The ability to synthesize multifunctional Zn-MOFs is a new chapter in the design of chemotherapeutic agents. A particular example is ZIF-8. The combination of different strategies for the influence of the pH value of the environment or photochemical elements gives the opportunity to use the compounds in imaging and cancer diagnosis.

2

Kofeina : właściwości i przykłady wykorzystania

Detlaff Grzegorz, Samaszko-Fiertek Justyna, Madaj Janusz, Dmochowska Barbara

Wiadomości Chemiczne

|

2020

|

[Z] 74, 7-8

527--543

EN

1,3,7-trimethyloxanthine commonly known as caffeine is naturally occurring alkaloid inter alia in coffee beans. It is acquired mainly in decaffeination of coffee process. It can also be synthesized by subsequent chemical reactions from uracil or by using enzymatic reaction assuming transfer of methyl group on xanthine derivatives by methyltransferase obtained from tea leaves. This alkaloid is associated mainly with coffee however it can be also found in tea or chocolate. With increasing age more and more caffeine from coffee and tea is consumed. Both drinks are its main source in human diet. During metabolite biotransformation caffeine is converted into three main products: theobromine (3,7-dimethylxanthine), theophylline (1,3-dimethylxanthine) and paraxanthine (1,7-dimethylxanthine). Caffeine polycrystals have ability to emit photons in radiative transition during phosphorescence at low temperature while its methanol solutions show fluorescence at low concentration. Caffeine might be used in synthesis of N-heterocyclic complex compound. Properly bonded with gold, silver or platinum atom might have many important properties. One of the most important properties is the possibility of binding free radicals that can cause DNA damage. Other significant properties of caffeine include its influence on the cell cycle and multiplication of cancer cells. 1,3,7- trimethylxanthine is also commonly used to reduce fatigue caused by inhibition of excitatory neurotransmitter emission. In this work we have presented interesting examples of the use of caffeine as a substrate in selected chemical syntheses. We have also included selected chemical and physical properties. In addition, we presented examples of its impact on the human body and consumption statistics based on international reports.

3

Aminokwasowe ciecze jonowe

Samaszko-Fiertek Justyna, Sowińska Kamila, Dmochowska Barbara, Ślusarz Rafał, Madaj Janusz

Wiadomości Chemiczne

|

2019

|

[Z] 73, 11-12

737--751

EN

Ionic liquids (IL) are defined as compounds consisting only of ions with a melting point below 100°C. [1,2,4]. The first obtained ionic liquid was ethylammonium nitrate synthesized in 1914 by Paul Walden as a result of the protonation of ethylamine with nitric acid [4]. New group of IL are amino acid ionic liquids. They are non-toxic and bio- renewable ionic liquids of natural origin. The amino acids contain at least two functional groups, an amino group and a carboxyl group, which makes them both cationic and anionic in the amino acid ionic liquid. Amino acid ionic liquids attract more and more attention in the field of catalysis, as solvents in chemical transformations and cellulose solvents due to low production costs and their biodegradable. Compounds based on imidazolium, phosphonium, ammonium and choline ionic liquids found a wide application in biological sciences, modern chemistry and materials science [10]. One of their biggest advantages is the ability to absorb CO2 (especially their amino acid derivatives), which increases the chance of eliminating carbon dioxide from the environment. Amino acid ionic liquids have also found application in the field of catalysis.