PEG-PCL Nanocapsules Containing Curcumin: Validation of HPLC Method for Analyzing Drug-loading Efficiency, Stability Testing and Cytotoxicity on NIH-3T3 Cell Line

Abstract Curcumin (CUR) shows potential use for treating cancer. However, CUR has low solubility and reduced bioavailability, which limit its clinical effect. Therefore, the development of nanocarriers can overcome these problems and can ensure the desired pharmacological effect. In addition, it is mandatory to prove the quality, the efficacy, and the safety for a novel nanomedicine to be approved. In that sense, this paper aimed (a) to prepare CUR-loaded polyethylene glycol-poly(ε-caprolactone) nanocapsules; (b) to validate an analytical method by high performance liquid chromatography (HPLC) for quantifying CUR in these nanoformulations; (c) to evaluate the physicochemical stability of these formulations; and to investigate their cytotoxicity on NIH-3T3 mouse fibroblast cells. The HPLC method was specific to CUR in the loaded nanocapsules, linear (r = 0.9994) in a range of 10.0 to 90.0 µg.mL-1 with limits of detection and quantification of 0.160 and 0.480 µg.mL-1, respectively. Precision was demonstrated by a relative standard deviation lower than 5%. Suitable accuracy (102.37 ± 0.92%) was obtained. Values of pH, particle size, polydispersity index, and zeta potential presented no statistical difference (p > 0.05) for CUR-loaded nanoparticles. No cytotoxicity was observed against NIH-3T3 mouse embryo fibroblast cell line using both the tetrazolium salt and sulforhodamine B assays. In conclusion, a simple and inexpensive HPLC method was validated for the CUR quantification in the suspensions of nanocapsules. The obtained polymeric nanocapsules containing CUR showed suitable results for all the performed assays and can be further investigated as a feasible novel approach for cancer treatment.

Paullinia cupana: a multipurpose plant - a review

Abstract Seeds of guarana (Paullinia cupana Kunth, Sapindaceae) feature diverse pharmacological functions, for example, antimicrobial, antioxidant, anticarcinogenic, stimulating, and cognitive functions, as well as liver protection and weight loss. Many of these actions are probably due to the high content of methylxanthines and tannins in its seeds. In Brazil, the world's largest producer of guarana, the plant material is predominantly used in the soft drinks industry, although it is also used in the cosmetic and pharmaceutical industries. Although the Amazon region has the largest cropping area, the state of Bahia is the main guarana producer in Brazil (71%). This review focuses mainly on the possible pharmacological actions of guarana that have been investigated. Moreover, it discusses less-considered topics, such as the toxicology and quality control of seeds and extractives of guarana that will ultimately influence the safety of its use. In addition, it presents a detailed discussion of the methods used to prepare herbal drugs and their extracts, focusing on the importance of standardization and on the direct impact of preparatory factors, on the pharmacological properties of guarana extracts.

A simple HPLC method for the determination of halcinonide in lipid nanoparticles: development, validation, encapsulation efficiency, and in vitro drug permeation

ABSTRACT Halcinonide is a high-potency topical glucocorticoid used for skin inflammation treatments that presents toxic systemic effects. A simple and quick analytical method to quantify the amount of halcinonide encapsulated into lipid nanoparticles, such as polymeric lipid-core nanoparticles and solid lipid nanoparticles, was developed and validated regarding the drug's encapsulation efficiency and in vitro permeation. The development and validation of the analytical method were carried out using the high performance liquid chromatography with the UV detection at 239 nm. The validation parameters were specificity, linearity, precision and accuracy, limits of detection and quantitation, and robustness. The method presented an isocratic flow rate of 1.0 mL.min-1, a mobile phase methanol:water (85:15 v/v), and a retention time of 4.21 min. The method was validated according to international and national regulations. The halcinonide encapsulation efficiency in nanoparticles was greater than 99% and the in vitro drug permeation study showed that less than 9% of the drug permeated through the membrane, indicating a nanoparticle reservoir effect, which can reduce the halcinonide's toxic systemic effects. These studies demonstrated the applicability of the developed and validated analytical method to quantify halcinonide in lipid nanoparticles.

Cytotoxicity of latex and pharmacobotanical study of leaves and stem of Euphorbia umbellata (Janaúba)

AbstractIn southern Brazil, the bottled latex of Synadenium grantii Hook f., Euphorbiaceae, is popularly used as a treatment of all types of cancer. Similarly, Synadenium umbellatum Pax. is used in the central western region of Brazil for the same purpose and in the same manner of use. Both plants are popularly known as janaúba or leitosinha. The objectives of this study were to use pharmacobotanical analysis to verify whether these two species, which are considered to be distinct, are actually the same to determine anatomical markers; to assist in the identification and differentiation of other Euphorbia; and to evaluate the cytotoxic activity of the latex in relation to HeLa and HRT-18 cells. Leaves and stems of the species were collected in Goiânia and Ponta Grossa and were investigated using scanning electron microscopy and optical microscopy techniques. The latex was also collected and analyzed in relation to its cytotoxic effect by employing MTT and NR techniques. The pharmacobotanical study of the specimens in both localities showed that they were the same species, namely Euphorbia umbellata (Pax) Bruyns, which is the scientific nomenclature accepted and confirmed by an expert taxonomist who specializes in Euphorbia. The pharmacobotanical characteristics highlighted in this study can assist in the identification of the taxon and contribute to the control of the quality of this plant drug. The evaluation of the latex in relation to HRT-18 cells demonstrated action after 48 h of experiment. In contrast, in relation to HeLa cells its induced cytotoxicity in all times and a dose-dependent manner. The IC50 values (72 h) observed were 252.58 ± 18.51 µg/ml and 263.42 ± 15.92 µg/ml to MTT experiment and 250.18 ± 19.48 µg/ml and 430.56 ± 19.71 µg/ml to NR experiment for the HeLa and HRT-18 cells, respectively.

Microparticles containing guaraná extract obtained by spray-drying technique: development and characterization

AbstractGuaraná (Paullinia cupana Kunth, Sapindaceae) is well known for its dietary and pharmaceutical potential, and the semipurified extract of guaraná shows antidepressant and panicolytic effects. However, the low solubility, bioavailability and stability of the semipurified extract limit its use as a component of pharmaceutical agents. Delivery of the semipurified extract in a microparticle form could help to optimize its stability. In this study, microparticles containing semipurified extract of guaraná were obtained by the spray-drying technique, using a combination of maltodextrin and gum arabic. The raw materials and microparticles produced were characterized by particle size analysis, differential scanning calorimetry, thermogravimetric analysis, and scanning electron microscopy. The drug content and antioxidant capacity were also evaluated. In vitrodissolution tests using flow cell dissolution apparatus, were carried out to investigate the influence of formulation parameters on the release of semipurified extract of guaraná from the microparticles. The spray-drying technique and the processing conditions selected gave satisfactory encapsulation efficiency (80–110%) and product yield (55–60%). The mean diameter of microparticles was around 4.5 µm. The DPPH radical scavenging capacity demonstrated that microparticles can protect the semipurified extract of guaraná from the effect of high temperatures during the process maintained the antioxidant capacity. Differential scanning calorimetry results indicated an interaction between semipurified extract of guaraná and gum arabic: maltodextrin in the microparticles, and thermogravimetric analysis indicate that the profile curves of the microparticles are similar to the adjuvants used in drying, probably due to the higher proportion of adjuvants compared to semipurified extract of guaraná. In vitro dissolution tests demonstrate that all formulations complete dissolution within 60 min. Microencapsulation improved the technological characteristics of the powders and preserved the antioxidant properties. The study demonstrated the feasibility of producing these microparticles for a one-step process using spray drying. The composition of each formulation influenced the physical and chemical characteristics. This spray-drying technique can be used as an efficient and economical approach to produce semipurified extract of guaraná microparticles.

Development of tablets containing semipurified extract of guaraná (Paullinia cupana)

This study evaluated the technological feasibility of producing a semipurified extract of guaraná (Paullinia cupana Kunth, Sapindaceae) in tablet form, using a direct-compression process. Maltodextrin and gum arabic were used to produce the extract microparticles, in order to protect the microparticles against such factors as temperature, oxidation, and humidity. Using pharmacopoeial methodologies, technological and physicochemistry tests (determination of residual moisture, of bulk and tapped density, Hausner ratio, compressibility and compactibility index, appearance, mean weight, hardness, friability, disintegration time, determination of EPA amount in tablets and in vitro release profile) were conducted. The formulation containing 200 mg of microparticles, 170 mg microcrystalline cellulose, and 10 mg lactose gave the best results in terms of hardness (116 N), friabilility (0.28%), mean weight (0.3821 g), and disintegration time (25 min) for a tablet designed for oral administration. The results met pharmacopoeial specifications, and the tablets are suitable for oral administration.

Contribuição ao protocolo de controle de qualidade da própolis e de seus extratos / Contribution to the quality control protocol of propolis and its extracts

Um protocolo de controle de qualidade da própolis (droga) e de seus extratos foi proposto no presente trabalho. Própolis coletada em colméias de abelhas Apis mellifera L., de apiário localizado na região noroeste do Estado do Paraná, foi triturada e submetida à determinação do tamanho médio das partículas, da perda por dessecação, do teor de cinzas, do teor de ceras, do teor de extrativos em água e em etanol 96°GL e do teor de flavonóides totais. Extratos etanólicos (96°GL) de própolis a 10 por cento (p/p) e a 30 por cento (p/p)foram preparados e submetidos à determinação do pH, da densidade relativa, do resíduo seco, do teor alcoólico e do teor de flavonóides totais. A própolis foi analisada, também, através de Cromatografia Líquida de Alta Eficiência (Clae). Neste trabalho compararam-se os resultados obtidos com os descritos na literatura, observando-se que é possível estabelecer faixas de valores para parâmetros que são importantes no protocolo de controle de qualidade de uma amostra de própolis de seus extratos.