Due to their unique properties, such as controlled drug release and improved bioavailability, polymeric microparticles and nanoparticles (MPs and NPs) have gained considerable interest in the pharmaceutical industry. Nevertheless, the high costs associated with biodegradable polymers and the active pharmaceutical ingredients (APIs) used for treating serious diseases, coupled with the vast number of API-polymer combinations, make the search for effective API-polymer MPs and NPs a costly and time-consuming process. In this work, the correlation between the compatibility of selected model APIs (i.e., ibuprofen, naproxen, paracetamol, and indomethacin) with poly(lactide-co-glycolide) (PLGA) derived from respective binary phase diagrams and characteristics of prepared MPs and NPs, such as the drug loading and solid-state properties, was investigated to probe the possibility of implementing the modeling of API-polymer thermodynamic and kinetic phase behavior as part of rational design of drug delivery systems based on MPs and NPs. API-PLGA-based MPs and NPs were formulated using an emulsion-solvent evaporation technique and were characterized for morphology, mean size, zeta potential, drug loading, and encapsulation efficiency. The solid-state properties of the encapsulated APIs were assessed using differential scanning calorimetry and X-ray powder diffraction. The evaluated compatibility was poor for all considered API-PLGA pairs, which is in alignment with the experimental results showing low drug loading in terms of amorphous API content. At the same time, drug loading of the studied APIs in terms of amorphous content was found to follow the same trend as their solubility in PLGA, indicating a clear correlation between API solubility in PLGA and achievable drug loading. These findings suggest that API-polymer phase behavior modeling and compatibility screening can be employed as an effective preformulation tool to estimate optimum initial API concentration for MP and NP preparation or, from a broader perspective, to tune or select polymeric carriers offering desired drug loading.

• Klíčová slova
• Active pharmaceutical ingredient, Compatibility, Drug delivery system, Micro/nano-particle, Phase diagram, Poly(lactide-co-glycolide),
• MeSH
• kopolymer kyseliny glykolové a mléčné chemie   MeSH
• léčivé přípravky MeSH
• lékové transportní systémy metody   MeSH
• nanočástice * chemie   MeSH
• nosiče léků chemie   MeSH
• polymery * chemie   MeSH
• velikost částic MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• dilactide MeSH Prohlížeč
• kopolymer kyseliny glykolové a mléčné MeSH
• léčivé přípravky MeSH
• nosiče léků MeSH
• polymery * MeSH

The development of an amorphous solid dispersion (ASD) is a promising strategy for improving the low bioavailability of many poorly water-soluble active pharmaceutical ingredients (APIs). The construction of a temperature-composition (T-C) phase diagram for an API-polymer combination is imperative as it can provide critical information that is essential for formulating stable ASDs. However, the currently followed differential scanning calorimetry (DSC)-based strategies for API solubility determination in a polymer at elevated temperatures are inefficient and, on occasions, unreliable, which may lead to an inaccurate prediction at lower temperatures of interest (i.e., T = 25 °C). Recently, we proposed a novel DSC-based protocol called the "step-wise dissolution" (S-WD) method, which is both cost- and time-effective. The objective of this study was to test the applicability of the S-WD method regarding expeditious verification of the purely-predicted API-polymer compatibility via the perturbed chain-statistical associating fluid theory (PC-SAFT) equation of state (EOS). Fifteen API-polymer T-C phase diagrams were reliably constructed, with three distinct API-polymer case types being identified regarding the approach used for the S-WD method. Overall, the PC-SAFT EOS provided satisfactory qualitative descriptions of the API-polymer compatibility, but not necessarily accurate quantitative predictions of the API solubility in the polymer at T = 25 °C. The S-WD method was subsequently modified and an optimal protocol was proposed, which can significantly reduce the required experimental effort.

• Klíčová slova
• Amorphous solid dispersion, PC-SAFT, Phase diagram, Solid–liquid equilibrium, Solubility, Step-wise dissolution,
• MeSH
• diferenciální skenovací kalorimetrie MeSH
• polymery * chemie   MeSH
• příprava léků metody   MeSH
• rozpustnost MeSH
• teplota MeSH
• termodynamika MeSH
• voda * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• polymery * MeSH
• voda * MeSH

The bioavailability of poorly water-soluble active pharmaceutical ingredients (APIs) can be improved via the formulation of an amorphous solid dispersion (ASD), where the API is incorporated into a suitable polymeric carrier. Optimal carriers that exhibit good compatibility (i.e., solubility and miscibility) with given APIs are typically identified through experimental means, which are routinely labor- and cost-inefficient. Therefore, the perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state, a popular thermodynamic model in pharmaceutical applications, is examined in terms of its performance regarding the computational pure prediction of API-polymer compatibility based on activity coefficients (API fusion properties were taken from experiments) without any binary interaction parameters fitted to API-polymer experimental data (that is, kij = 0 in all cases). This kind of prediction does not need any experimental binary information and has been underreported in the literature so far, as the routine modeling strategy used in the majority of the existing PC-SAFT applications to ASDs comprised the use of nonzero kij values. The predictive performance of PC-SAFT was systematically and thoroughly evaluated against reliable experimental data for almost 40 API-polymer combinations. We also examined the effect of different sets of PC-SAFT parameters for APIs on compatibility predictions. Quantitatively, the total average error calculated over all systems was approximately 50% in the weight fraction solubility of APIs in polymers, regardless of the specific API parametrization. The magnitude of the error for individual systems was found to vary significantly from one system to another. Interestingly, the poorest results were obtained for systems with self-associating polymers such as poly(vinyl alcohol). Such polymers can form intramolecular hydrogen bonds, which are not accounted for in the PC-SAFT variant routinely applied to ASDs (i.e., that used in this work). However, the qualitative ranking of polymers with respect to their compatibility with a given API was reasonably predicted in many cases. It was also predicted correctly that some polymers always have better compatibility with the APIs than others. Finally, possible future routes to improve the cost-performance ratio of PC-SAFT in terms of parametrization are discussed.

• Klíčová slova
• PC-SAFT, amorphous solid dispersions, compatibility, drugs, polymers, prediction, solubility,
• MeSH
• léčivé přípravky MeSH
• polymery * chemie   MeSH
• příprava léků MeSH
• rozpustnost MeSH
• termodynamika MeSH
• voda * chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• léčivé přípravky MeSH
• polymery * MeSH
• voda * MeSH

Prediction of compatibility of the active pharmaceutical ingredient (API) with the polymeric carrier plays an essential role in designing drug delivery systems and estimating their long-term physical stability. A key element in deducing API-polymer compatibility is knowledge of a complete phase diagram, i.e., the solubility of crystalline API in polymer and mutual miscibility of API and polymer. In this work, the phase behavior of ibuprofen (IBU) with different grades of poly(D,L-lactide-co-glycolide) (PLGA) and polylactide (PLA), varying in composition of PLGA and molecular weight of PLGA and PLA, was investigated experimentally using calorimetry and computationally by the perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state (EOS). The phase diagrams constructed based on a PC-SAFT EOS modeling optimized using the solubility data demonstrated low solubility at typical storage temperature (25 °C) and limited miscibility (i.e., presence of the amorphous-amorphous phase separation region) of IBU with all polymers studied. The ability of PC-SAFT EOS to capture the experimentally observed trends in the phase behavior of IBU-PLA/PLGA systems with respect to copolymer composition and molecular weight was thoroughly investigated and evaluated.

• Klíčová slova
• API–polymer compatibility, PC-SAFT, PLA, PLGA, amorphous solid dispersion, biodegradable polymers, phase diagrams,
• Publikační typ
• časopisecké články MeSH

Many anticancer active pharmaceutical ingredients (APIs), such as paclitaxel (PTX), exhibit poor water solubility, which limits their bioavailability and necessitates the use of excipients. While biodegradable polymeric excipients combined with nanotechnology offer promising solutions, the high cost of polymers and APIs, along with the vast number of potential API-polymer combinations, poses significant challenges in developing effective drug delivery systems (DDS). This study explores the potential of API-polymer phase behavior modeling as part of the design of nanoparticle (NP)-based DDS for PTX using poly(lactide-co-glycolide) (PLGA) and poly(lactide-co-glycolide)-b-poly(ethylene glycol) (PLGA-PEG) with varying molecular weights. The phase behavior of PTX-PLGA/PLGA-PEG systems, which reflects the compatibility of PTX with polymeric excipients, was predicted using the Conductor-like Screening Model for Real Solvents (COSMO-RS). To investigate the correlation between the predictions and experimental observations, PTX-PLGA and PEGylated PLGA NPs were prepared via an emulsion-solvent evaporation method with varying initial PTX amounts. The predicted trends in PTX solubility in polymeric excipients were then compared with key NP characteristics, such as drug loading, solid-state properties, and cytotoxicity in HeLa, SKOV-3, and MRC-5 cells. COSMO-RS predictions indicated limited PTX solubility in PLGA, which aligns with experimental observations, where the maximum amorphous PTX loading did not exceed 2 wt%, regardless of the polymer molecular weight. COSMO-RS modeling predicted higher compatibility of PTX with PEG, suggesting that incorporating PEG would enhance PTX loading in PEGylated NPs. This trend was corroborated by experimental findings, which showed increased drug loading capacity and slower PTX release from PEGylated NPs during cytotoxicity studies. These results highlight the potential of API-polymer modeling as a tool for tailoring polymeric carriers and optimizing API consumption in NP-based DDS development.

• Klíčová slova
• COSMO-RS, Cell tests, Compatibility, Drug delivery systems, Nanoparticles, PLGA copolymers, Paclitaxel,
• MeSH
• fytogenní protinádorové látky * chemie   aplikace a dávkování   farmakologie   MeSH
• kopolymer kyseliny glykolové a mléčné * chemie   MeSH
• lékové transportní systémy MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nanočástice * chemie   aplikace a dávkování   MeSH
• nosiče léků * chemie   MeSH
• paclitaxel * chemie   aplikace a dávkování   farmakologie   MeSH
• polyethylenglykoly chemie   MeSH
• polyglactin 910 * chemie   MeSH
• pomocné látky chemie   MeSH
• rozpustnost MeSH
• uvolňování léčiv MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fytogenní protinádorové látky * MeSH
• kopolymer kyseliny glykolové a mléčné * MeSH
• nosiče léků * MeSH
• paclitaxel * MeSH
• polyethylenglykoly MeSH
• polyglactin 910 * MeSH
• pomocné látky MeSH

The quantum mechanics-aided COSMO-SAC activity coefficient model is applied and systematically examined for predicting the thermodynamic compatibility of drugs and polymers. The drug-polymer compatibility is a key aspect in the rational selection of optimal polymeric carriers for pharmaceutical amorphous solid dispersions (ASD) that enhance drug bioavailability. The drug-polymer compatibility is evaluated in terms of both solubility and miscibility, calculated using standard thermodynamic equilibrium relations based on the activity coefficients predicted by COSMO-SAC. As inherent to COSMO-SAC, our approach relies only on quantum-mechanically derived σ-profiles of the considered molecular species and involves no parameter fitting to experimental data. All σ-profiles used were determined in this work, with those of the polymers being derived from their shorter oligomers by replicating the properties of their central monomer unit(s). Quantitatively, COSMO-SAC achieved an overall average absolute deviation of 13% in weight fraction drug solubility predictions compared to experimental data. Qualitatively, COSMO-SAC correctly categorized different polymer types in terms of their compatibility with drugs and provided meaningful estimations of the amorphous-amorphous phase separation. Furthermore, we analyzed the sensitivity of the COSMO-SAC results for ASD to different model configurations and σ-profiles of polymers. In general, while the free volume and dispersion terms exerted a limited effect on predictions, the structures of oligomers used to produce σ-profiles of polymers appeared to be more important, especially in the case of strongly interacting polymers. Explanations for these observations are provided. COSMO-SAC proved to be an efficient method for compatibility prediction and polymer screening in ASD, particularly in terms of its performance-cost ratio, as it relies only on first-principles calculations for the considered molecular species. The open-source nature of both COSMO-SAC and the Python-based tool COSMOPharm, developed in this work for predicting the API-polymer thermodynamic compatibility, invites interested readers to explore and utilize this method for further research or assistance in the design of pharmaceutical formulations.

• Klíčová slova
• COSMO-SAC, amorphous solid dispersions (ASD), drug−polymer thermodynamic compatibility, miscibility, prediction, quantum mechanics, solubility,
• MeSH
• farmaceutická chemie metody   MeSH
• léčivé přípravky chemie   MeSH
• nosiče léků chemie   MeSH
• polymery * chemie   MeSH
• rozpustnost * MeSH
• termodynamika * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• léčivé přípravky MeSH
• nosiče léků MeSH
• polymery * MeSH

In this work, the solid-liquid equilibrium (SLE) curve for ten active pharmaceutical ingredients (APIs) with the polymer polyvinylpyrrolidone (PVP) K12 was purely predicted using the Conductor-like Screening Model for Real Solvents (COSMO-RS). In particular, two COSMO-RS-based strategies were followed (i.e., a traditional approach and an expedited approach), and their performances were compared. The veracity of the predicted SLE curves was assessed via a comparison with their respective SLE dataset that was obtained using the step-wise dissolution (S-WD) method. Overall, the COSMO-RS-based API-PVP K12 SLE curves were in satisfactory agreement with the S-WD-based data points. Of the twenty predicted SLE curves, only two were found to be in strong disagreement with the corresponding experimental values (both modeled using the expedited approach). Hence, it was recommended to use the traditional approach when predicting the API-polymer SLE curve. At the present moment, COSMO-RS may be an effective computational tool for the expeditious screening of API-polymer compatibility, particularly in the case of promising novel APIs, for which experimental datasets are likely limited or non-existent.

• Klíčová slova
• Amorphous solid dispersion, COSMO-RS, Drug–polymer, Phase diagram, Solid–liquid equilibrium, Solubility,
• MeSH
• farmaceutická chemie metody   MeSH
• léčivé přípravky chemie   MeSH
• polymery chemie   MeSH
• povidon * chemie   MeSH
• rozpouštědla chemie   MeSH
• rozpustnost MeSH
• uvolňování léčiv MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• léčivé přípravky MeSH
• polymery MeSH
• povidon * MeSH
• rozpouštědla MeSH

Poor aqueous solubility of crystalline active pharmaceutical ingredients (APIs) restricts their bioavailability. Amorphous solid dispersions with biocompatible polymer excipients offer a solution to overcome this problem, potentially enabling a broader use of many drug candidate molecules. This work addresses various aspects of the in silico design of a suitable combination of an API and a polymer to form such a binary solid dispersion. Molecular interactions in such bulk systems are tracked at full atomic resolution within molecular-dynamics (MD) simulations, enabling to identify API-polymer pairs that exhibit the most beneficial interactions. Importance of these interactions is manifold: increasing the mutual miscibility, kinetic stabilization of their amorphous dispersions and impedance of the spurious recrystallization of the API component. MD tools are used to investigate the structural and cohesive properties of pure compounds and mixtures, with a special emphasis on molecular interactions, microscopic structures and internal dynamics. This analysis is then accompanied by a macroscopic image of the energetic compatibility and vitrification tendency of the mixtures in terms of their excess enthalpies and glass transition temperatures. Density-functional theory (DFT) and non-covalent interaction (NCI) analysis fortify our computational conclusions and enable us to map the intensities of particular NCI among the individual target materials and relevant molecular sites therein. Three archetypal polymer excipients and four API molecules are included in this study. The results of our computational analysis of molecular interactions in bulk systems agree with the experimentally observed trends of solubility of the given API in polymers. Our calculations confirm PVP as the most potent acceptor of hydrogen bonding among the three considered polymer excipients, whereas ibuprofen molecules are predicted to be the most efficient hydrogen bond donors among our four target APIs. Our simulations also suggest that carbamazepine does not exhibit particularly strong interactions with the considered polymer excipients. Although current MD cannot offer quantitative accuracy of many of the discussed descriptors, current computational models focusing on NCI of APIs with polymer excipients contribute to understanding of the behavior of these materials at the molecular level, and thus also to the rational design of novel efficient drug formulations.

• MeSH
• ibuprofen chemie   MeSH
• kinetika MeSH
• krystalizace MeSH
• léčivé přípravky * chemie   MeSH
• polymery chemie   MeSH
• pomocné látky chemie   MeSH
• rozpustnost MeSH
• simulace molekulární dynamiky MeSH
• teorie funkcionálu hustoty MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ibuprofen MeSH
• léčivé přípravky * MeSH
• polymery MeSH
• pomocné látky MeSH