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Nanoparticle Synthesis and Administration Routes for Antiviral Uses
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
João Augusto Oshiro-Júnior, Kammila Martins Nicolau Costa, Isadora Frigieri, Bruna Galdorfini Chiari-Andréo
Every drug administered orally goes through a series of pathways until it is completely absorbed. The drug is initially administered through the mouth, and it ultimately reaches the mesenteric veins and then the hepatic portal vein; then it is transported directly to the liver, which normally metabolizes a large part of the medication, launching the active drug to reach systemic circulation, but with a reduced concentration range. This process is called first-pass or pre-systemic metabolism, where a small portion of the medication is eliminated by the organ responsible for its elimination. This process determines that the oral route has a lower bioavailability when compared to an intravenous administration (Ahmad et al. 1984).
Carbon Nanotubes in Cancer Therapy
Published in Yasser Shahzad, Syed A.A. Rizvi, Abid Mehmood Yousaf, Talib Hussain, Drug Delivery Using Nanomaterials, 2022
Renu Sankar, V.K. Ameena Shirin, Chinnu Sabu, K. Pramod
Most of the anticancer drugs available now are nonselective in nature. This nonselectivity results in damage to normal cells causing unwanted side effects to the body. This is the main reason for the increased death rate of cancer patients. The lower bioavailability of these drugs results in increased drug dose requirement leading to toxicities. Additionally, it may result in multidrug resistance. Hence it is necessary to develop a delivery system that targets the cancer cells and produces improved therapeutic effects. Nanomaterials are currently used for the efficient delivery of anticancer drugs to the target site. The CNTs are employed for this purpose. The smaller size of CNTs permits the passive transport of drugs to the target cell (Muller et al. 2009). The properties like high drug loading capacity, large surface area, high aspect ratio, and small size make CNTs an ideal candidate for cancer therapy. The CNTs help for the pH-dependent release of the drug thereby promoting target-specific delivery which will reduce the side effects and frequency of drug administration (Elhissi et al. 2012).
Multi-Cyclodextrin Supramolecular Encapsulation Entities for Multifaceted Topical Drug Delivery Applications
Published in Munmaya K. Mishra, Applications of Encapsulation and Controlled Release, 2019
P. D. Kondiah, Yahya E. Choonara, Zikhona Hayiyana, Pariksha J. Kondiah, Thashree Marimuthu, Lisa C. du Toit, Pradeep Kumar, Viness Pillay
Topical and localized drug delivery is the direct administration of pharmaceuticals for local effects. This mode of drug delivery is advantageous due to site targeting, elimination of systemic effects, and improved drug encapsulation efficiency. This route of drug delivery presents inherent benefits. These include bypassing hepatic clearance, which improves drug bioavailability, limited systemic adverse events due to toxic drug blood levels, and prevention of unwanted effects in other body organs. Cyclodextrins, after topical administration, increase the amount of drug available at the surface of biological membranes such as the surface of tissues, skin, and mucosal membranes. This improves the drug’s bioavailability by ensuring that the drug is available for absorption. It has been suggested in previous work that cyclodextrins themselves do not penetrate biological membranes (Shelley and Babu 2018). After delivering the drug to the membrane surface, cyclodextrins remain extracellular, as seen in Figure 1.4. This also means that possible intracellular damage is avoided. By attaching to the membrane surface, cyclodextrins may also improve the membrane permeability by binding with membrane components. Cyclodextrins are non-irritant to the surfaces of tissue, skin, and mucosa.
Estimation of lurasidone hydrochloride equilibrium solubility in a polymeric solid dispersion using thermal analysis and thermodynamic modeling
Published in Journal of Dispersion Science and Technology, 2023
Joško Barbarić, Krunoslav Žižek, Marko Rogošić
Oral administration of drugs maintains its dominant position as the most common, most acceptable and adaptable route of drug application. The consequent bioavailability of orally applied drugs is dependent on various factors with the most important ones being solubility in aqueous gastrointestinal media, drug permeability, rate of dissolution, effects of first-pass metabolism etc. In order to facilitate prediction of gastrointestinal absorption of drugs based on their solubility and permeability properties, a four class Biopharmaceutical Classifications System (BCS) has been implemented. More than 40% of newly developed drugs are practically insoluble in aqueous environment[1] and are placed in class 2 (poor solubility, high permeability) and class 4 (poor solubility, low permeability) of the BCS system.
Process variables that defined the phytofiltration efficiency of invasive macrophytes in aquatic system
Published in International Journal of Phytoremediation, 2023
Yetunde Irinyemi Bulu, Nurudeen Abiola Oladoja
Uptake of pollutants from the aquatic system are often limited by their concentration and bioavailability. The bioavailability depends on several factors, which include, concentrations, chemical form, metal property, binding state, organic matter, pH value, root exudates and interaction between compounds. At higher concentration, the effective removal of pollutants by macrophytes is hindered. For example, Rai (2008) reported a gradual reduction in the percentage of Hg (90, 94, and 80%) and Cd (90, 91, and 70%) removal from an increasing concentration of 0.5, 1 and 3 g/L, respectively, when Azolla pinnatum was exposed to industrial effluents for 13 d. A similar result of 99.4, 99.5, 95.6, and 95.4% for Cd removal, at 0.5, 1, 2, and 4 mg/L, respectively, and 83.6, 75.8, 74.7, 84.3% for Zn removal, at 5, 10, 20 and 40 mg/L were reported for Cd and Zn uptake by P. crassipes (Lu et al.2004).
Mathematical modelling of drug-diffusion from multi-layered capsules/tablets and other drug delivery devices
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2022
Drugs are chemical or biological compounds that affect the human body and its functioning. The drug delivery to the biological tissues through diffusion and absorption occurs when it enters the circulatory system. The level of absorption can affect the speed and amount of the drug and its side of action. This is called bioavailability. If a tablet/capsule or some other drug delivery device (DDD) releases the drug quickly, blood levels may become too high whereas slow release may result in low levels of absorption. Addition of factors affecting bioavailability and absorption of the drugs, include properties of the drug and the physiology of the person, such as pH levels in the stomach and its speed of emptying. Therefore, specific formulations are used to release the drug at a desired speed. Common formulations include capsules, tablets, transdermal patches, solutions and other DDDs (Borchardt et al. 1996). To this end, mathematical modeling of diffusional and release processes provides detailed insights to simulate the biological systems and biomedical phenomena with the aid of computational power (Sidig 2015). To depict the desired release of the drug (from a capsule/tablet or other DDDs), to the targeted biological tissue, mathematical models in drug delivery have played a vital role to design and shape the drug delivery systems (Peppas and Narasimhan 2014).