探索和分析纳米颗粒的系统输送障碍

Drug distribution in the body is intricately regulated by various physiological barriers that control the passage of substances. These include the capillary endothelial barrier, the blood-brain, blood-cerebrospinal fluid, blood-placental, and blood-testis barriers.
The capillary endothelial barrier allows only smaller molecules below 600 Da (Daltons) to pass through. It also restricts drugs like heparin that are bound to blood components, limiting their movement within the bloodstream.
The...

The selection of a drug's delivery route depends upon its physicochemical properties, including lipid or water solubility and ionization, as well as the therapeutic requirement, such as immediate or sustained effect. These routes can be divided into three primary categories: enteral, parenteral, and topical.
Enteral delivery involves administering drugs directly through swallowing, sublingual placement, or buccal application. Orally administered drugs predominantly navigate the...

Drug delivery methods like oral inhalation, nasal sprays, transdermal patches, eye drops, intravitreal injection,  and rectal administration provide localized effects with reduced toxicity.
Oral inhalation and nasal sprays swiftly transfer drugs across the respiratory epithelium's mucosal layer. Inhaled glucocorticoids and bronchodilators directly target lung conditions such as asthma, while fluticasone nasal spray mitigates allergic rhinitis.
Transdermal patches transport drugs...

The parenteral route is a critical method of drug administration. It delivers compounds directly into the systemic circulation and bypasses the gastrointestinal tract. This approach is particularly advantageous for drugs that exhibit poor absorption or instability when administered orally.
There are three primary parenteral routes: intravenous (IV), intramuscular (IM), and subcutaneous (SC). The IV route introduces the drug directly into the bloodstream, ensuring immediate action. The IM route...