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Background/Objectives: Camptothecin (CPT) is a well-known chemical compound recognized for its significant anticancer properties. However, its clinical application remains limited due to challenges related to CPT's high hydrophobicity and the instability of its active form. To address these difficulties, our research focused on the development of four novel nanoparticulate systems intended for either oral or intravenous administration. Methods: These nanosystems were based on a poly(amidoamine) (PAMAM) dendrimer/CPT complex, which had been coated with biodegradable homo- and copolymers, designed with appropriate physicochemical properties and chain microstructures. Results: The resulting nanomaterials, with diameters ranging from 110 to 406 nm and dispersity values between 0.10 and 0.67, exhibited a positive surface charge and were synthesized using biodegradable poly(L-lactide) (PLLA), poly(L-lactide-co-ε-caprolactone) (PLACL), and poly(glycolide-co-ε-caprolactone) (PGACL). Biological assessments, including cell viability and hemolysis tests, indicated that all polymers demonstrated less than 5% hemolysis, confirming their hemocompatibility for potential intravenous use. Furthermore, fibroblasts exposed to these matrices showed concentration-dependent viability. The entrapment efficiency (EE) of CPT reached up to 27%, with drug loading (DL) values as high as 17%. The in vitro drug release studies lasted over 400 h with the use of phosphate buffer solutions at two different pH levels, demonstrating that time-dependent processes allowed for a gradual and controlled release of CPT from the developed nanosystems. The release kinetics of the active compound at pH 7.4 ± 0.05 and 6.5 ± 0.05 followed near-first-order or first-order models, with diffusion and Fickian/non-Fickian transport mechanisms. Importantly, the nanoparticulate systems enabled the stabilization of the pharmacologically active form of CPT, while providing protection against hydrolysis, even in physiological environments. Conclusions: In our opinion, these results underscore the promising future of biodegradable nanosystems as effective drug delivery systems (DDSs) for targeted cancer treatment, offering stability and efficacy over short, medium, and long-term applications. [ABSTRACT FROM AUTHOR]

Polylactide is an important material in biomedical applications, but its slow degradation rate, low hydrophilicity, and lack of reactive side-chain groups limit its use. To overcome these limitations it is crucial to functionalize it with reactive groups. By introducing reactive functional side groups, biologically active compounds can be attached with the possibility of controlled release. Additionally, introducing suitable functional groups can improve hydrophilicity, which is essential for drug delivery. There are several ways to introduce reactive functional side groups to the polylactide chain, with the most versatile being the introduction of a reactive group into monomeric lactide and its subsequent polymerization or copolymerization with lactide. This approach allows the preparation of polylactides with pendent functional groups via the polymerization of functional (substituted) monomers. Therefore, the synthetic strategy based on functional monomers is considered the primary option to access a broad range of functional polylactides. This review focuses on the modification of polylactide by incorporating functional groups into monomer molecules and their subsequent polymerization. Through this approach, it is possible to improve the properties of polylactide for various biomedical applications. In the following sections, we will discuss the different methods for functionalization and their potential impact on the biomedical field. [ABSTRACT FROM AUTHOR]

Molar mass correction coefficients (cc) were determined for calculating the absolute molar masses of polylactide (PLA), polycaprolactone (PCL), and poly(2,2‐dimethyltrimethylene carbonate) (PDTC) in the range of 2,5–190 kg/mol, using calibration based on polystyrene standards (PS). Linear PLAs, PCLs, and PDTCs with a wide range of molar masses were synthesized using tin (II) octoate and diol as a catalyst/initiator system. Size Exclusion Chromatography (SEC) coupled with a Refractive Index detector (SEC‐RI) or a Multi‐Angle Laser Light Scattering detector (SEC‐MALLS) was utilized to determine the relative molar mass or absolute molar mass of the samples under investigation. Additionally, for comparison, the absolute molar mass of low molar mass PLA, PCL, or PDTC was calculated based on end‐group analysis using the 1H NMR method. Correction coefficients were subsequently calculated by comparing the molar mass obtained from SEC‐MALLS and SEC‐RI. The calculated correction coefficients ranged from 0.40 to 0.87 and increased with the rising molar mass of the polymers. The derived equation could be used to evaluate the absolute molar masses from PS standards over a broad range for the analyzed polymers. [ABSTRACT FROM AUTHOR]

The reactive oxirane groups were incorporated into the macromolecule as substituents in the side chains of loosely-grafted copolymer or in the arms of star-shaped copolymer using glycidyl methacrylate (GMA) in the controlled atom transfer radical polymerization (ATRP). The branched GMA copolymers with various architectures were obtained by using hydrophobic copolymers containing six and seven units of caprolac-tone 2-(methacryloyloxy)ethyl ester (CLMA) functionalized with bromoester groups, and trifunctional poly(ζ-caprolactone) (PCL), as well as hydrophilic tri-, and six-functional acetal derivatives of D-glucopyranosides as (macro)initiators with biodegradable and biocompatible properties. The well-defined copolymers with core-shell structures and polymerization degrees of GMA in the range of 20-100 per side chain/arm at 20-70% of monomer conversion within 1-6 h and narrow molecular weight distributions ([M.sub.w] / [M.sub.n] = 1.14-1.4) were obtained. POLYM. ENG. SCI., 53:1146-1153, 2013. © 2012 Society of Plastics Engineers, INTRODUCTION Glycidyl methacrylate (GMA) contains two reactive groups, vinyl and oxirane, which can be used selectively depending on polymerization method. In anionic polymerization according to ring-opening mechanism polyethers with vinylic [...]

In this study, the influence of homehold composting conditions on the molecular and supramolecular structure of polylactide (PLA) in the form of spun-bonded nonwovens was investigated. Nonwoven samples were studied using size-exclusion chromatography coupled with multiangle laser light scattering detection, wide-angle X-ray diffraction, differential scanning calorimetry and Fourier transform infrared spectroscopy. In addition, the physical and mechanical properties of the nonwovens before and after composting were determined. The results show the varying degree of influence of the prepared compost mixtures of soil with common horticultural additives, such as chalk, commercially available agents, cow manure and chicken litter, on the molecular and supramolecular structure of PLA and its degradation rate. The obtained experiment explained which popular homehold agent had the strongest affect on the PLA nonwoven dedicated for agriculture use in the first period of season composting (first 6 months). [ABSTRACT FROM AUTHOR]

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