A new deferiprone controlled release system obtained by ultrasound-assisted compression

Application of validated UV-Vis spectrophotometry-colorimetric methods for specific quantification of deferiprone in the development of iron-responsive nanoparticle loaded into dissolving microneedle

Deferiprone (DFP) is one of the iron-chelating agents used in iron overload therapy for patients with ß-thalassemia major (ß-TM). However, the use of DFP is limited as it experiences a first-pass effect and can potentially cause iron deficiency due to uncontrolled release. Therefore, iron-responsive (NP-IR) DFP nanoparticle innovation was developed to control DFP release. A dissolving microneedle system (NP-IR-DMNs) was used to maximize DFP release. However, in support of this development, validation of analytical methods using spectrophotometry and colorimetrics was carried out. UV-Vis spectrophotometry is an approach that is easy to use, practical, and more cost-effective than others. The DFP levels were determined in normal and iron-overloaded medium solutions with 1%, 2%, and 4% concentrations. In addition, DFP levels were also measured in rat plasma using the colorimetric method with the addition of FeCl3 reagent to increase sensitivity for the detection of the analyte. The procedures used as guidelines in the validation procedure are The International Council for Harmonization (ICH). As a result, all linear correlation values of medium and plasma ≥ 0.999 were obtained. The LOQ levels obtained were 0.55 µg/mL, 0.44 µg/mL, 0.42 µg/mL, 0.52 µg/mL, and 1.01 µg/mL in plasma, 1% FeSO4, 2% FeSO4, 4% FeSO4, and normal media, respectively. The accuracy and precision were confirmed valid, as all values were within the requirements and did not change during dilution. Then, this approach was successfully applied to determine the levels of DFP in NP-IR integrated into DMNs.

Chelators for Treatment of Iron and Copper Overload: Shift from Low-Molecular-Weight Compounds to Polymers

Iron and copper are essential micronutrients needed for the proper function of every cell. However, in excessive amounts, these elements are toxic, as they may cause oxidative stress, resulting in damage to the liver and other organs. This may happen due to poisoning, as a side effect of thalassemia infusion therapy or due to hereditary diseases hemochromatosis or Wilson's disease. The current golden standard of therapy of iron and copper overload is the use of low-molecular-weight chelators of these elements. However, these agents suffer from severe side effects, are often expensive and possess unfavorable pharmacokinetics, thus limiting the usability of such therapy. The emerging concepts are polymer-supported iron- and copper-chelating therapeutics, either for parenteral or oral use, which shows vivid potential to keep the therapeutic efficacy of low-molecular-weight agents, while avoiding their drawbacks, especially their side effects. Critical evaluation of this new perspective polymer approach is the purpose of this review article.

Achieving High Excipient Efficiency with Elastic Thermoplastic Polyurethane by Ultrasound Assisted Direct Compression

Ultrasound assisted compression (USAC) is a manufacturing technique which applies thermal and mechanical energy to the powder bed, producing tablets with improved characteristics compared to the direct compression process. This technology is ideal for thermoplastic materials, as polyurethanes, whose particles usually undergo a sintering process. Thermoplastic polyurethanes are widely used in sustained drug release systems but rarely seen in tablets due to their elastic properties. The aim of this work is to investigate the ability of USAC to manufacture sustained release matrix tablets based on elastic thermoplastic polyurethanes (TPU), overcoming the limitations of direct compression. The technological and biopharmaceutical characteristics of the TPU matrices have been evaluated, with special focus on the porous structure due to the implications on drug release. For the first time, USAC has been successfully employed for manufacturing elastic thermoplastic polyurethanes-based matrices. TPU tablets show an inert character with a sustained drug release governed by a diffusional mechanism. Initial porosity of matrices was similar in all batches studied, with no influence of drug particle size, and a fractal nature of the pore network has been observed. SEM microphotographs show the continuum medium created by the sintering of the polymer, responsible for the high excipient efficiency.

Novel Polyurethane Matrix Systems Reveal a Particular Sustained Release Behavior Studied by Imaging and Computational Modeling

The aim of the present work was to better understand the drug-release mechanism from sustained release matrices prepared with two new polyurethanes, using a novel in silico formulation tool based on 3-dimensional cellular automata. For this purpose, two polymers and theophylline as model drug were used to prepare binary matrix tablets. Each formulation was simulated in silico, and its release behavior was compared to the experimental drug release profiles. Furthermore, the polymer distributions in the tablets were imaged by scanning electron microscopy (SEM) and the changes produced by the tortuosity were quantified and verified using experimental data. The obtained results showed that the polymers exhibited a surprisingly high ability for controlling drug release at low excipient concentrations (only 10% w/w of excipient controlled the release of drug during almost 8 h). The mesoscopic in silico model helped to reveal how the novel biopolymers were controlling drug release. The mechanism was found to be a special geometrical arrangement of the excipient particles, creating an almost continuous barrier surrounding the drug in a very effective way, comparable to lipid or waxy excipients but with the advantages of a much higher compactability, stability, and absence of excipient polymorphism.