Nanomedical applications

Nanoparticles are tiny particles that are dimensioned in the nanometer scale (1 nanometer = 1 billionth of a meter). They are made of different materials such as metals, semiconductors, polymers or organic substances and can have a variety of shapes, including spheres, rods or complex structures. Due to their tiny size, nanoparticles often exhibit unique physical, chemical or optical properties that render them attractive for a wide range of applications.

Nanoparticles are used in various fields such as medicine (e.g. for targeted pharmaceutical delivery), electronics (e.g. for improved sensors or displays), environmental technology (e.g. for water treatment) and cosmetics (e.g. for sunscreens). 

Transfer systems are special technologies or carrier systems that are used to transport or deliver drugs to specific areas of the body. These systems can be designed in various ways to improve the efficacy, safety and targeted application of drugs. The most common transfer systems include:

Liposomes: These are man-made vesicles made up of lipid layers that can trap active ingredients in their hollow chambers. Liposomes can be used to transport and control the release of drugs.

Nanoparticles: These are very small particles in the nanometer range that can consist of different materials (e.g. metals, polymers). Nanoparticles can enclose active substances or carry them on their surface and thus facilitate their uptake into cells or tissue.

Polymer-based microparticles: These are small particles of polymers that can contain and release active ingredients in a controlled manner. They are often used to extend the retention time of drugs in the body or to release them in a targeted manner.

Hydrogels and nanogels: These are networks of water and polymers that can trap active ingredients and act as a matrix to deliver drugs locally.

Dendrimers: These are synthetic molecules that have a tree structure and can enclose active substances in their branches. They are being investigated for various medical applications, including targeted drug delivery.

Transfer systems play a crucial role in modern medicine as they can help to target drugs, control their release and reduce side effects by minimizing uptake into healthy tissues and maximizing concentration in diseased tissues or cells.

The term "cosmeceutical" is a combination of the words "cosmetics" and "pharmaceuticals", as these products combine properties from both areas. They contain active ingredients that go beyond purely cosmetic effects and have a certain therapeutic effect on the skin.

In contrast to pure cosmetics, cosmeceuticals can contain higher concentrations of active ingredients that have proven positive effects on the skin. These active ingredients can have antioxidant, anti-inflammatory, moisturizing or anti-aging properties, for example.

Cosmeceuticals are often used to treat specific skin problems such as acne, wrinkles, hyperpigmentation or for general skin care. They fall between purely cosmetic products, which primarily offer aesthetic improvements, and pharmaceutical preparations, which have to meet stricter regulatory requirements and are often used for medical purposes.

Biofunctionalization refers to the process by which biological molecules, such as proteins, enzymes, antibodies or DNA, are specifically bound to the surfaces of materials or nanoparticles. This is typically done by chemical or physical methods to modify the surface with biologically active molecules.

The main objectives of biofunctionalization are:

Improving biocompatibility: By binding biological molecules, materials can interact better with biological systems, which improves their compatibility and their use in biological or medical applications.

Enhancement of functionality: The bound biological molecules can confer specific functions, such as the recognition of target structures (e.g. specific cells or pathogens) or the modulation of biological processes.

Examples of biofunctionalization include the binding of antibodies to the surfaces of biosensors for the detection of pathogens, the modification of nanoparticles with peptides for the targeted delivery of drugs or the immobilization of enzymes on carrier materials for the catalytic conversion of substrates.

In nanotechnology and biotechnology, biofunctionalization plays a decisive role in equipping materials with specific biological functions and expanding their applications in areas such as medicine, diagnostics, environmental technology and food technology.

Rheology is the study of the flow behavior of liquids and viscoelastic materials. A rheology modifier is used to influence the viscosity and flow properties of a material. These modifiers are used in various industries such as cosmetics, the paint and coatings industry, the food industry, the building materials industry and the pharmaceutical industry. They help to improve the processing properties of materials, increase stability and achieve the desired properties of the end product.

Defoamers are chemical substances that are used to reduce or prevent the formation of foam in industrial processes. Foam is created by trapping air bubbles in a liquid and can have undesirable consequences in various industries, such as food processing, chemical production, paper manufacturing and wastewater treatment.

The use of defoamers aims to control the formation of foam and improve the stability of products or processes. They act by reducing the surface tension of the liquid or suppressing the formation of air bubbles. Defoamers typically consist of surface-active substances that are able to destabilize and destroy air bubbles.

Emulsifiers are substances that are used to stabilize an emulsion. An emulsion is a mixture of two normally immiscible liquids, such as oil and water. Emulsifiers have the ability to reduce the interfacial tension between these two liquids and prevent the phases from separating again. They help to stabilize finely dispersed particles of one liquid (e.g. oil) in the other liquid (e.g. water).

Bioemulsifiers are emulsifiers that are obtained naturally or come from natural sources. They can be obtained from plant or animal sources, such as vegetable oils, beeswax or certain proteins. They can also be biodegradable.

Both types of emulsifiers are used in numerous applications, including in the food industry (to produce emulsions such as mayonnaise or salad dressings), in cosmetics (to stabilize creams and lotions), in pharmaceuticals (to produce drug emulsions) and in agriculture (to improve the effectiveness of crop protection products).

An emulsion is created by mixing two or more non-mixable liquids, typically in the form of an oil-water mixture. In this mixture, finely dispersed droplets of one liquid are evenly distributed in another liquid. An emulsion usually consists of a dispersed phase, in which the fine droplets are located, and a continuous phase, which is the liquid in which the droplets are dispersed.

There are two main types of emulsions: Oil-in-water (O/W) and water-in-oil (W/O). In an oil-in-water emulsion, the oil droplets are distributed in the water phase, whereas in a water-in-oil emulsion, the water droplets are distributed in the oil phase.

Emulsions play a crucial role in various fields such as the food industry (e.g., in salad dressings and mayonnaise), cosmetics (e.g., in creams and lotions), and the pharmaceutical industry (e.g., in drug formulations). They make it possible to combine different ingredients that are normally immiscible into a homogeneous and stable form, leading to improved product characteristics such as uniform distribution, increased shelf life, and optimal functionality.

The use of UV absorbers is crucial to protect both human skin and materials from the harmful effects of UV radiation. They play a central role in maintaining material integrity and skin health by effectively absorbing UV rays and converting them into harmless heat.

Application in sunscreens: In the cosmetics industry, UV absorbers are essential ingredients in sunscreens. They prevent UV rays from penetrating the skin and causing damage that can lead to premature skin ageing and skin cancer. Protection is mainly achieved through absorption, with around 90 per cent of the protective effect being attributable to this mechanism.

Protection of materials: UV absorbers are used in coatings, plastics and paints to minimise the effects of UV radiation. This radiation can lead to colour loss, cracking and the degradation of materials. By absorbing UV radiation, UV absorbers convert the energy into harmless heat, thereby preserving the physical and optical properties of the materials.

Types of UV absorbers: UV absorbers can be divided into organic and inorganic types. Organic absorbers such as benzophenones and hydroxybenzophenones are commonly found in sunscreens, while inorganic absorbers such as zinc oxide and titanium dioxide are used in various applications, including cosmetics and coatings.