PAMAM Dendrimers: A Review of Methodologies Employed in Biopharmaceutical Classification

The oral route is the preferred way of drug administration for most drugs, whose treatment success is directly related to the compound intestinal absorption. This absorption process, in its turn, is influenced by several factors impacting the drug bioavailability, which is extremely dependent on the maximum solubility and permeability. However, optimizing these last two factors, without chemical structural modification, is challenging. Although poly(amidoamine) dendrimers (PAMAM) are an innovative and promising strategy as drug delivery compounds, there are few studies that determine the permeability and solubility of PAMAM-drugs derivatives. Considering this scenario, this paper aimed to carry out a literature review of the last five years concerning biopharmaceutical characterizations of dendrimer delivery systems. In vitro methodologies, such as the Parallel artificial membrane permeability assay (PAMPA) (non-cellular based model) and Caco-2 cells (cellular based model), used for the permeability evaluation in the early stages of drug discovery proved to be the most promising methodologies. As a result, we discussed, for instance, that through the usage of PAMPA it was possible to evaluate the higher capacity for transdermal delivery of DNA of TAT-conjugated PAMAM, when in comparison with unmodified PAMAM dendrimer with a P<0.05. We also presented the importance of choosing the best methods of biopharmaceutical characterization, which will be essential to guarantee the efficacy and safety of the drug candidate.

Modulation of biopharmaceutical properties of acidic drugs using cationic counterions: A critical analysis of FDA-approved pharmaceutical salts

Salification has a successful track record in modulating the biopharmaceutical properties of drugs. This is evident from the significant share (40%) of pharmaceutical salts in FDA-approved drugs in the past 80-years. Based on the ionic nature of drugs, the corresponding cationic or anionic counterions are employed for salification. This review aims to provide the contribution of cationic counterions in FDA-approved drugs from 1939 to 2020. The analysis of 80-years data has shown that the 7.1% of the FDA-approved drugs comprise cationic counterions (98 pharmaceutical salts). Heparin sodium is the pioneering drug in the history of pharmaceutical salts that was approved in 1939 as an anticoagulant medication. Inorganic (sodium, calcium, potassium, magnesium, silver), as well as organic (tromethamine, meglumine, erbumine) cationic counterions, were used in FDA-approved drugs with a major share by sodium (76 drugs). The technical superiority of cationic salts over other salt forms and the parent drug is also exemplified using case studies.

Co-crystal nanoarchitectonics as an emerging strategy in attenuating cancer: Fundamentals and applications

Cancer ranks as the second foremost cause of death in various corners of the globe. The clinical uses of assorted anticancer therapeutics have been limited owing to the poor physicochemical attributes, pharmacokinetic performance, and lethal toxicities. Various sorts of co-crystals or nano co-crystals or co-crystals-laden nanocarriers have presented great promise in targeting cancer via improved physicochemical attributes, pharmacokinetic performance, and reduced toxicities. These systems have also demonstrated the controlled cargo release and passive targeting via enhanced permeation and retention (EPR) effect. In addition, regional delivery of co-crystals via inhalation and transdermal route displayed remarkable potential in targeting lung and skin cancer effectively. However, more research is required on the use of co-crystals in cancer and their commercialization. The present review mainly emphasizes co-crystals as emerging avenues in the treatment of various cancers by modulating the physicochemical and pharmacokinetic attributes of approved anticancer therapeutics. The worth of co-crystals in cancer treatment, computational paths in the co-crystals screening, diverse experimental techniques of co-crystals fabrication, and sorts of co-crystals and their noteworthy applications in targeting cancer are also discussed. Besides, the game changer approaches like nano co-crystals and co-crystals-laden nanocarriers, and co-crystals in regional delivery in cancer are also explained with reported case studies. Furthermore, regulatory directives for pharmaceutical co-crystals and their scale-up, and challenges are also highlighted with concluding remarks and future initiatives. In essence, co-crystals and nano co-crystals emerge to be a promising strategy in overwhelming cancers through improving anticancer efficacy, safety, patient compliance, and reducing the cost.

Biopharmaceutical studies of a novel sedative sublingual lozenge based on glycine and tryptophan: A rationale for mucoadhesive agent selection

Effective sedative drugs are in great demand due to increasing incidence of nervous disorders. The present work was aimed to develop a novel sublingual sedative drug based on glycine and L-tryptophan amino acids. Carbopol and different hydroxypropyl methylcellulose species were alternatively tested as mucoadhesive agents intended to prolong tryptophan sublingual release time. A model lipid medium of fully hydrated L-α-dimyristoylphosphatidylcholine was used for optimal mucoadhesive agents selection. Simultaneous processes of drug release and diffusion in lipid medium were first investigated involving both experimental and theoretical approaches. Individual substances, their selected combinations as well as different drug formulations were consecutively examined. Application of kinetic differential scanning calorimetry method allowed us to reveal a number of specific drug-excipient effects. Lactose was found to essentially facilitate tryptophan release and provide its ability to get into the bloodstream simultaneously with glycine, which is necessary to achieve glycine-tryptophan synergism. Introduction of a mucoadhesive agent into the formulation was shown to change kinetics of drug-membrane interactions variously depending on viscosity grade. Among the mucoadhesive agents, hydroxypropyl methylcellulose species K4M and E4M were shown to further accelerate drug release, therefore they were selected as optimal. Thus, effectiveness of the novel sedative drug was provided by including some excipients, such as lactose and the selected mucoadhesive agent species. A dynamic mathematical model was developed properly describing release and diffusion in lipid medium of various drug substances. Our study clearly showed applicability of a lipid medium to meet challenges such as drug-excipient interactions and optimization of drug formulations.

Interpreting the efficacy enhancement mechanism of Chinese medicine processing from a biopharmaceutic perspective

Chinese medicine processing (CMP) is a unique pharmaceutical technology that distinguishes it from natural medicines. Current research primarily focuses on changes in chemical components to understand the mechanisms behind efficacy enhancement in processing. However, this paper presents a novel perspective on the biopharmaceutics of CMP. It provides a comprehensive overview of the current research, emphasizing two crucial aspects: the role of 'heat' during processing and the utilization of processing adjuvants. The paper highlights the generation of easily absorbed components through the hydrolysis of glycosides by 'heat', as well as the facilitation of dissolution, absorption, and targeted distribution of active components through the utilization of processing adjuvants. From a biopharmaceutic perspective, this paper provides a lucid comprehension of the scientific foundation for augmenting the efficacy of CMP. Moreover, it proposes a three-dimensional research framework encompassing chemical reactions, phase transitions, and biopharmaceutical properties to further investigate the mechanisms involved in enhancing the efficacy of CMP.

Oral absorption mechanisms of polysaccharides and potential as carriers for the construction of nano-delivery systems: A review

Polysaccharides have garnered increasing attention in recent years for their potential in oral drug delivery within biomaterials and pharmaceuticals, owing to their excellent physicochemical properties, bioactivity, and low toxicity. However, the absorption of polysaccharides encounters multiple challenges posed by the biological, chemical, mechanical, and immune barriers of the intestinal mucosa. Therefore, elucidating the mechanisms by which polysaccharides traverse the intestinal mucosa for oral absorption is essential for their further development and application. Current studies have identified several polysaccharide absorption pathways, including transcellular transport, paracellular transport, M cell and Peyer's patches mediated transport, and intestinal flora mediated transport. Furthermore, numerous studies have demonstrated that polysaccharides can enhance the solubility, gastrointestinal stability, and permeability of small molecule components, which significantly improves their bioavailability. More importantly, nano-delivery systems utilizing polysaccharides as carriers have shown great promise in enhancing the targeting of small molecule components, thereby opening new avenues for drug delivery applications. We hope this review will provide theoretical support and inspiration for a deeper understanding of oral absorption mechanisms and the potential of polysaccharides in the development of nano-delivery systems.