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Granulation of Poorly Water-Soluble Drugs
Published in Dilip M. Parikh, Handbook of Pharmaceutical Granulation Technology, 2021
Albert W. Brzeczko, Firas El Saleh, Hibreniguss Terefe
Complexation is well known in organic and inorganic chemistry. Complexes are entities comprising two or more molecules (or ions) that are bound to each other with non-covalent bonds, that is, only with physical forces such as hydrogen bonds or van der Waals bonds [26].
Membrane Transport
Published in Lelio G. Colombetti, Biological Transport of Radiotracers, 2020
The fourth type of ionophoric carrier is the charged carrier which has the property that it can form a complexation structure around an ion.38 These carriers are electrically silent and therefore will not show manifestations of ion transport in BLMs. A system to measure transport properties of charged ionophores is the Pressman cell.38 Two aqueous compartments are separated by a layer of organic solvent, a radioactive ion is added to one compartment and the appearance of radioactivity in the second compartment in the presence or absence of ionophore is measured. Complexation is also studied by solvent extraction, pH titration, and spectroscopic methods. The best known in this series of charged carriers are monensin, nigericin X537A, and the Ca2+ ionophore A23187.38
Nanocarriers Systems and Their Application for the Delivery of Different Phytoconstituents
Published in Madhu Gupta, Durgesh Nandini Chauhan, Vikas Sharma, Nagendra Singh Chauhan, Novel Drug Delivery Systems for Phytoconstituents, 2020
Ebru Altuntaş, Gülgün Yener, Burcu Özkan
A phospholipid-based complexation approach was used to improve the permeability and solubility of the Standardized Bacopa extract (SBE) (Saoji et al., 2016). The complex of SBE-phospholipid (Bacopa Naturosome, BN) with several ratios of SBE and Phospholipon® 90H, i.e. 1:0.5, 1:1, 1:1.75, 1:2.5, or 1:3 was produced using a solvent evaporation technique. To optimize the process variables and formulation, a central-composite design was applied. Under the optimized conditions, the yield for the batches of BN was found to be 87.09%. Analysis has demonstrated that the zeta potential value and mean particle size of the optimized BN were −37.6 ± 1.1 mV and 395 ± 11 nm, respectively. A notable higher aqueous solubility was obtained with BN against to the phospholipid and the physical mixture of SBE (13-fold) or pure SBE (20-fold). Furthermore, this prepared complex (BN) has a considerably higher yield in release of the SBE (>97%) against to the physical mixture (~47%) or pure SCE (~42%) as a result of in vitro dissolution study. Results of the ex-vivo permeation study experiments revealed that the permeation of SBE (>90%) was significantly enhanced by the prepared BN compared with the physical mixture (~24%) or the pure SBE (~21%). It is concluded that complexation of drug and phospholipid can be a rational approach in order to improve the solubility of phytomedicines.
Chrysin–phospholipid complex-based solid dispersion for improved anti-aging and neuroprotective effects in mice
Published in Pharmaceutical Development and Technology, 2023
Abeer Salama, Rania Elgohary, Ahmed Alaa Kassem, Marwa Hasanein Asfour
PL complex (PLC) is a vesicle resembling a liposome, formed by self-assembly in an aqueous medium, based on the formation of non-covalent bonds (such as hydrogen bonds, van der Waals forces, charge transfer, etc.) between PL and the molecules of the phytocompounds (Semalty Ajay et al. 2010). Drug-PL complexation has been previously reported to play a potential role in enhancing drug permeation through the intestinal wall (Huang et al. 2019; Jain et al. 2019). However, the strong stickiness of PLC leads to its poor dispersion, causing unsatisfactory dissolution and oral absorption of the drugs (Zhou et al. 2017; Li et al. 2020; Chakravarti et al. 2021). Therefore, it is important to select an appropriate carrier to disperse PLC in order to increase the dissolution of the drugs (Zhou et al. 2017; Li et al. 2020). The literature has demonstrated an enhancement in drug activity through dual formulation strategies, namely, PLC-loaded micelles (Kassem et al. 2017), nanolipospheres (Beg et al. 2016), matrix films (Telange et al. 2019), and SDs (Zhou et al. 2017; Li et al. 2020; Yeo et al. 2020; Chakravarti et al. 2021).
Transdermal delivery via medical device technologies
Published in Expert Opinion on Drug Delivery, 2022
Shubhangi Shukla, Ryan H. Huston, Blake D. Cox, Abhay R. Satoskar, Roger J. Narayan
Complexation is yet another method that can be suitable to improve water solubility of certain drugs. For example, propofol is an anesthetic that is highly lipophilic; this characteristic has led to two main formulations being developed in the clinic, including surfactant-based and oil-emulsion-based delivery; however, both of these can result in distinct side effects for patients, hence a new delivery mechanism is required [120,121]. The hydrophobic nature of propofol renders it ineffective at delivery via iontophoresis when it is delivered alone. A novel ionized version of propofol was shown to be effective in iontophoresis; however, this ionized version has altered bioavailability, possibly impacting its accumulation in the brain and throughout the body [122]. These challenges led to an investigation of the complexation of propofol and the common solubilizing agent, cyclodextrin, for use in iontophoresis [122]. Complexation of propofol with cyclodextrin was shown via NMR as well as UV absorption spectra and resulted in a linear increase of soluble propofol correlated 1:1 with the concentration of cyclodextrin [122]. These large (2 kDa) complexes were tested under iontophoresis as well as passive transport. The complex enhanced propofol passive transport; the enhancement of propofol delivery in ex vivo porcine skin was attributed to increased thermodynamic activity and the delayed recovery of the skin barrier (due to disruption by iontophoresis) [122].
A promising dual-drug targeted delivery system in cancer therapy: nanocomplexes of folate–apoferritin-conjugated cationic solid lipid nanoparticles
Published in Pharmaceutical Development and Technology, 2021
Abbas Amer Ridha, Soheila Kashanian, Ronak Rafipour, Abbas Hemati Azandaryani, Hossein Zhaleh, Elahe Mahdavian
Apoferritin (AFr) is an attractive protein drug delivery system, it forms a self-assembled cage-like scaffold with a suitable drug binding site in its inner core (Kilic et al. 2012). AFr systems have also proven to be biocompatible and safe (Ghosh et al. 2016). AFr is a ubiquitous intracellular and a blood serum protein, composed of a total of 24 subunits of two types, ferritin L and ferritin H. The ratio of these two subunits varies depending on cell type. AFr self assembles into a hollow cage with an interior and outer diameter of 8 and 12 nm, respectively (Kilic et al. 2012). The AFr cage dissociates into its components in an acidic environment (pH 2.0) and reassembles at pH 7.4 (Zhen et al. 2013), which serves as the basis for drug loading (DL) and release in AFr systems. The AFr protein cage may be loaded with small molecules by means of a passive process typically well-suited for metals and ions. Certain pharmacotherapeutic drugs serve as optimal agents for small molecule-AFr complexation. As a drug delivery system, AFr has also demonstrated improved potency and selectivity for certain anticancer agents (Belletti et al. 2017).