The assembly of nano-biomaterials made a series of advances in two-photon photodynamic therapy

Photodynamic therapy (PDT) is a new cancer therapy that has gained much attention in recent years. This method is uniquely selective compared to traditional therapies. However, PDT photosensitive drugs (such as photoporphyrin) which are usually used in clinic effectively absorb light energy only in the visible light region below 700 nm, and such light usually can not reach deep tissues due to strong scattering effect. One improved method is the application of two-photon excited technology (TPE) to PDT, which is excited by a light source that is double the absorption wavelength of the sample under the excitation of a strong pulsed laser (in the infrared or near infrared region) For photodynamic therapy from the superficial treatment to the deep tissue treatment to expand the possible options.

Recently, a series of nano-biomaterials, such as biocompatible microcapsules prepared by the layer-by-layer self-assembly technique, were obtained through the assembly method supported by the National Natural Science Foundation of China and the Ministry of Science and Technology (Angew. Chem. Int Mater. 2012, 22, 1446-1453), or by biomolecule-induced preparation of mesoporous silica nanoparticles (Adv. Funct. Mater. 2016, 26, 2561-2570; ACS Appl. Mater. Interfaces 2016, 8, 8900-8907). Two-photon dyes and conventional photosensitizers are co-assembled to allow two-photon dyes and photosensitizers to undergo fluorescence resonance energy transfer (FRET) in confined spaces within the assembled nanomaterials described above to obtain two-photon excitation photodynamic therapy TPE-PDT) system. The assembly of the TPE-PDT system is designed to broaden the selection of two-photon dyes and photosensitizers and to precisely control FRET efficiency at the nanometer scale.

Figure: Microcapsules prepared by multilayer assembly for FRET analysis and two-photon photodynamic therapy

Pneumatic Solenoid Valve

Solenoid valve is an industrial equipment controlled by electromagnetism. It is an automatic basic component used to control fluid. It belongs to actuator. Pneumatic solenoid valve is one of them. It blocks or leaks different oil drain holes by controlling the movement of valve body. The oil inlet hole is normally open, and hydraulic oil will enter different oil drain pipes, Then the oil pressure of the pneumatic solenoid valve pushes the piston of the oil cylinder. In this way, the mechanical movement of the whole solenoid valve is controlled by controlling the current of the electromagnet of the pneumatic solenoid valve.

Characteristic

It can work normally under vacuum, negative pressure and zero pressure, but its diameter is generally less than 25 mm.

It can also operate under zero pressure difference, vacuum and high pressure, but it has high power and must be installed horizontally.

The upper limit of fluid pressure range is high, which can be installed arbitrarily (need to be customized), but the condition of fluid pressure difference must be met.

Principle editing voice

There is a closed cavity in the pneumatic solenoid valve, and there are through holes in different positions. Each hole of the pneumatic solenoid valve leads to different gas pipes. There is a valve in the middle of the cavity and two electromagnets on both sides. The valve body will be attracted to which side when the magnet coil is electrified;

The pneumatic solenoid valve blocks or leaks different exhaust holes by controlling the movement of the valve body, and the air inlet is normally open. High pressure gas will enter different exhaust pipes, and then push the piston of the cylinder through the air pressure of the pneumatic solenoid valve. In this way, the mechanical movement of the whole solenoid valve is controlled by controlling the current of the electromagnet of the pneumatic solenoid valve.

Operation principle of pneumatic solenoid valve

We said the pneumatic solenoid valve working position (solenoid valve on or off), in fact, refers to the pneumatic solenoid valve spool position.

Pneumatic Solenoid Valve, Pneumatic Air Solenoid Valve, Electronic Solenoid Air Valve

Glove Industry Co.,Ltd. , https://www.glovemech.com

Posted on