Biopelículas activas de extracto acuosos de Gliricidia sepium y su influencia en la vida útil microbiológica del queso costeño / Active biofilms of aqueous extract of Gliricidia sepium and its influence on the microbiological shelf life of coastal cheese

RESUMEN La elaboración de biopelículas con propiedades bioactivas es un área interesante en el campo de los empaques alimentarios. El objetivo de este estudio fue obtener biopelículas activas (BPA) a base de extracto acuoso de hojas de Gliricidia sepium y determinar su efecto en la vida útil microbiológica del queso costeño. Para la fabricación de las BPA, el extracto acuoso fue microencapsulado, mediante gelación iónica y, posteriormente, incorporado en las biopelículas. La determinación de la vida útil de muestras de queso costeño, se llevó a cabo mediante microbiología predictiva, utilizando el modelo de Monod Hinshelwood. Las microcápsulas utilizadas tuvieron un diámetro promedio de 273,786µm. Los resultados mostraron un aumento en la vida útil microbiológica de 26,7 días, en quesos con BPA, almacenado a 7°C, en comparación con una muestra control (sin BPA), confirmando que las BPA investigadas ejercen un efecto inhibitorio sobre los microorganismos, causantes de deterioro en quesos. Por tal motivo, la metodología aquí planteada puede ser una alternativa en la conservación de un producto perecedero, como el queso costeño.

ABSTRACT The elaboration of biofilms with bioactive properties is an interesting area in the field of food packaging. The aim of this study was to obtain active biofilms (AB) based on aqueous extract of Gliricidia sepium leaves and determine their effect on the microbiological shelf life of coastal cheese. For the manufacture of the AB, the aqueous extract was microencapsulated by means of ionic gelation and later incorporated in the biofilms. The coastal cheese's shelf life was carried out by means of predictive microbiology using the Monod Hinshelwood model. The microcapsules had an average diameter of 273.786µm. The results showed an increase in the microbiological shelf life of 26.7 days in cheeses with AB stored at 7°C compared with control sample (without AB) confirming that the AB investigated exerts an inhibitory effect on the microorganisms causing deterioration in cheeses. For this reason, the methodology proposed here can be an alternative in the conservation of a perishable product such as coastal cheese.

Enhanced dissolution and eliminated gelation of lenvatinib mesylate by coamorphous system / 中国药科大学学报

@#Lenvatinib mesylate (LF), a multi-target tyrosinase inhibitor mainly used in the treatment of a variety of cancers, has low oral bioavailability mainly due to its gelation during the dissolution process. In the current study, in order to enhance dissolution and eliminate gelation of LF, a supramolecular coamorphous system of LF-baicalein (BAI) (molar ratio, 1∶1) was prepared by rotary evaporation and characterized by PLM, PXRD, DSC and FTIR. Results indicated the formation of coamorphous system with a single Tg of 118 °C. Different from original LF crystal, no gelation phenomenon was observed during the dissolution of coamorphous LF-BAI. In addition, the dissolution rate of LF was increased by 2.2-fold after coamorphization. Meanwhile, the dissolution rate of the co-former BAI was also enhanced by more than 25.4-fold. Stability test showed that the prepared coamorphous system had a good physical stability for at least 90 days under 25 °C/ 60%RH and 40 °C /75%RH conditions.

Gelation of small molecule amorphous drugs / 药学学报

Compared with crystalline drugs, their amorphous forms present long-range disordered molecular arrangements, and often exhibit higher apparent solubility and dissolution. However, several small molecule amorphous drugs may exhibit gelation phenomenon during the dissolution process, and show abnormal dissolution behavior with significantly lower dissolution than crystalline drugs. The current study aims to discover the relationship between the gelation of amorphous drugs and their abnormal dissolution, and further explore the internal gelation mechanism. Amorphous simvastatin (SIM), carvedilol (CAR), and irbesartan (IRB) were prepared by melt cooling method and characterized via X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FT-IR). Gel formation causes the dissolution of these three amorphous drugs to be significantly lower than their crystalline state. The formed gels were characterized as three-dimensional dense network structures by scanning electron microscope (SEM). Furthermore, amorphous SIM, CAR and IRB showed the critical gel temperature at 8-15 ℃, 25-30 ℃ and 45-50 ℃, and amorphous CAR and IRB showed the critical gel pH at 1 and 0.25. The mechanism of gel formation was proposed to be closely related to the transformation of amorphous drugs into the supercooled liquid state (as the important driving force) and the protonation induced self-assembling under acidic conditions. In addition, the wettability and properties of amorphous drugs also affect the formation of gelation.

Bioactive compounds in jamelão yogurt (Syzygium cumini L) / Compostos bioativos em iogurte de jamelão (Syzygium cumini L)

The jamelão fruit has been used in traditional Indian medicine and has recently attracted interest as a functional food, as it is rich in anthocyanins. Anthocyanins are of interest of the food industry due to their antioxidant power, attractive color and stability in acid-rich foods. This research used the gelation process with sodium alginate solution to obtain bioactive yogurt from the production of jamelão capsules added to natural yogurt. The proportion was 80% yogurt and 20% jellybean pulp capsules. The treatments were control yogurt (without the addition of jamelão capsules), jamelão capsules and bioactive yogurt (with the capsules). The objective was to study the antioxidant activity, physical-chemical, nutritional and microscopic stability of the product kept under refrigeration for 28 days at 4±1ºC. The addition of jamelão capsules in the yogurt changed the product's physical properties (increased humidity and decreased Brix and ash). There was an increase in the amount of phenols and anthocyanins, in addition to the antioxidant potential at 28 days of storage. The interior of the microcapsules was composed of a mesh structure through which the encapsulated material was distributed, as the capsules can be added to yogurt, to improve the antioxidant and nutritional capacity, which proves to be a promising and viable alternative.

A fruta Jamelão tem sido usada na medicina tradicional indiana e recentemente atrai interesse como alimento funcional, por ser rica em antocianinas. As antocianinas são de interesse da indústria de alimentos devido ao seu poder antioxidante, cor atraente e estabilidade em alimentos ácidos. Esta pesquisa utilizou o processo de gelificação com solução de alginato de sódio para obter iogurte bioativo, a partir da produção de cápsulas de jamelão adicionadas em iogurte natural. A proporção utilizada foi de 80% de iogurte e 20% de cápsulas de polpa de jamelão. Os tratamentos foram iogurte controle (sem adição de cápsulas de jamelão), cápsulas de jamelão e iogurte bioativo (contendo as cápsulas). O objetivo foi estudar a atividade antioxidante, a estabilidade físico-química, nutricional e microscópica do produto mantido sob refrigeração por 28 dias a 4 ± 1 ºC. A adição de cápsulas de jamelão no iogurte alterou as propriedades físicas do produto (aumento de umidade, diminuição de Brix e cinzas). Houve aumento na quantidade de fenóis e antocianinas, além do potencial antioxidante aos 28 dias de armazenamento. O interior das cápsulas era composto por uma estrutura em malha através da qual o material encapsulado foi distribuído. Desta forma, as cápsulas podem ser um ingrediente adicionado ao iogurte, melhorando a capacidade antioxidante e nutricional, provando ser uma alternativa promissora e viável.

Evaluación de la estabilidad de cápsulas de jugo de naranja obtenidas mediante gelificación iónica / Evaluation of the stability of orange juice capsules obtained by ionic gelation

Resumen El método de gelificación iónica, como técnica de encapsulación, se basa en las interacciones entre hidrocoloides, las cuales previenen la posibilidad de daño de compuestos bioactivos presentes en alimentos, tales como los jugos de cítricos. El objetivo del presente estudio fue evaluar la estabilidad de las cápsulas de jugo de naranja, obtenidas mediante gelificación iónica, utilizando pectina y alginato de sodio como agentes encapsulantes. Se determinaron la pérdida de peso, atributos de color, diámetro, morfología macroscópica y densidad en cápsulas elaboradas. Se utilizó un diseño factorial, modificando la concentración de pectina de alto metoxilo (1.5 %, 2 % y 2.5 % p/v), pH (2.5, 3.5 y 4.5) y sólidos solubles totales (SST) a 5 ºBrix y 15 ºBrix, manteniendo constante la concentración de alginato de sodio al 0.5 % (p/v), y se almacenaron a temperatura ambiente (26 ºC) y refrigeración (4 ºC) durante 12 d. Las cápsulas presentaron principalmente forma esférica (> 45 %). Los atributos de color permanecieron estables durante 12 d de almacenamiento. Los SST iniciales y el pH influyeron en la estabilidad de las cápsulas. A una concentración de 15 ºBrix y pH 2.5 no se pudieron formar de manera adecuada las cápsulas, presentando mayor sinéresis y morfologías amorfas. Las cápsulas de jugo de naranja con concentración de pectina 2 % (p/v), alginato de sodio 0.5 % (p/v), SST 5 ºBrix y pH 2.5, se mantuvieron estables con parámetros de calidad apropiados al ser almacenadas a temperatura de refrigeración (4 ºC). El método de gelificación iónica mediante encapsulación ofrece una alternativa para prolongar la vida útil del jugo, y el desarrollo de nuevos productos elaborados a partir de este cítrico.

Abstract The ionic gelation method as an encapsulation technique is based on the interactions between hydrocolloids, which prevent the possibility of damage of bioactive compounds present in foods, such as citrus juice. Therefore, the objective of the present study was to evaluate the stability of the orange juice capsules obtained by ionic gelation using pectin and sodium alginate as encapsulating agents. The effects of the gelling agents on the stability were determined by the measurement of weight loss, diameter, color attributes, diameter, macroscopic morphology, density in elaborate capsules. In addition, a factor analysis design was used by modifying the concentration of high methoxyl pectin (1.5 %, 2 % and 2.5 % w/v), pH (2.5, 3.5 and 4.5) and total soluble solids (TSS) at 5 ºBrix and 15 ºBrix, maintaining the concentration of sodium alginate constant at 0.5 % (w/v). The capsules were stored at room temperature (26 ºC) and refrigeration (4 ºC) for 12 d. They mainly presented a spherical shape (> 45 %). The color attributes remained stable even after 12 d of storage. The initial TSS and pH influenced the stability of the capsules. At a concentration of 15 ºBrix and pH 2.5, the capsules could not be adequately formed, capsules presenting greater syneresis and amorphous morphologies. However, the orange juice capsules remained stable for more than 2 weeks and with stable quality parameters when stored at refrigeration temperature (4 ºC), pectin concentration 2 % (w/v), sodium alginate 0.5 % (w/v), TTS 15 ºBrix and pH 2.5. The ionic gelation method through encapsulation offers an alternative to extend the shelf life of the juice and the development of new products made from this citrus.

A Review On Chitosan Nanoparticles

The chitosan nanoparticles because of their biodegradability, biocompatibility,better stability, low toxicity, simple and mild preparation methods, offer a valuable tool tonovel drug delivery systems in the present. The methods such as micro emulsion method,emulsification solvent diffusion method are also in use. The present review describesproperties, different methods of preparation and applications of chitosan nanoparticles

Study on process and rheological parameters of Kucha gynaecological gel / 中草药

Objective To investigate the preparation process of Kucha gynecological gel and prepare a temperature-sensitive in situ gel capable of rapid phase change in vagina. Methods Poloxamer P188 and Poloxamer P407 were used as gel matrix, Lactic acid and sodium lactate were used as the acid buffer solution. The central composite design was performed to optimize the prescription and technology, and the gelation temperature (GT), gelation time, and the effects of different acid buffer solutions on GT, gel stability, and related rheological properties were determined. Results Within a certain concentration range, the gelation temperature was gradually increased with the increase of poloxamer 188 concentration, and the gelation temperature was gradually decreased with the increase of poloxamer 407 concentration, and the optimized prescription by central composite design was poloxamer P188 with a concentration of 3.51% and poloxamer P407 with a concentration of 17.16%. The addition of different buffers has a deviation of 5% of the gelation temperature of the gel in vitro, but the variation in the vaginal fluid is large. The gelation temperatures of the citric acid-sodium citrate buffer and the lactic acid-sodium lactate buffer solution in the vaginal fluid were 68.5 ℃ and 35.8 ℃, respectively, and the rheological data showed that the gel retained better in vivo. Conclusion The Kucha gynecological gel preparation corresponded with the model employed by central composite design, and the screened process can prepare situ gels with good retention and stable properties.

Improvement of the viability of probiotics (Lactobacillus acidophilus) by multilayer encapsulation / Melhoramento da viabilidade de probióticos (Lactobacillus acidophilus) por encapsulação em multicamadas

ABSTRACT: This study produced pectin microcapsules containing Lactobacillus acidophilus by external ionic gelation, followed by the adsorption of whey protein and pectin to form multilayers. The viability of free and microencapsulated lactobacilli was evaluated after in vitro exposure to gastrointestinal conditions. They were also assessed by heat treatment, and stability was examined at -18 °C, 5 °C and 25 °C for 120 days. Exposure to different pHs, simulating passage through the gastrointestinal tract, showed that treatment of the microcapsules with only pectin (LA/P0) and with one and two layers of whey protein (treatments LA/P1 and LA/P3, respectively), were able to protect Lactobacillus acidophilus , with microcapsules increasing the release of probiotics from the stomach into the intestines. Free cells showed a decrease in their counts over the course of the simulated gastrointestinal system. Regarding heat treatments, microcapsules with a layer of whey protein (LA/P1) maintained the viability of their encapsulated Lactobacillus acidophilus (9.57 log CFU/g-1). The best storage viability was at -18 °C, with a count of 7.86 log CFU/g-1at 120 days for microcapsule LA/P1,with those consisting of two layers of whey protein (LA/P3)having a 6.55 log CFU/g-1 at 105 days. This study indicated that external ionic gelation was effective and could be used for the production of pectin microcapsules, with multilayer whey protein promoting greater protection and viability of Lactobacillus acidophilus.

RESUMO: O objetivo deste trabalho foi produzir microcápsulas de pectina, contendo Lactobacillus acidophilus por gelificação iônica externa, seguida da adsorção de proteína de soro de leite e multicamadas formadoras de pectina. Além disso, a viabilidade de lactobacilos livres e microencapsulados, após exposição in vitro a condições gastrintestinais, foi avaliada após simulação de tratamentos térmicos e, finalmente, estabilidade a -18 ºC, 5 ºC e 25 ºC durante 120 dias de armazenamento. A exposição a diferentes pHs, simulando a passagem pelo trato gastrointestinal, mostrou que os tratamentos das microcápsulas com apenas pectina (LA/P0) e com uma e duas camadas proteína do soro (tratamentos LA/P1 e LA/P3, respectivamente), foram capazes de proteger o Lactobacillus acidophilus , enquanto as microcápsulas aumentaram a liberação de probióticos do estômago para o intestino. As células livres diminuíram suas contagens no curso do sistema. Em relação aos tratamentos térmicos aplicados, pode-se afirmar que a microcápsula com uma camada de proteína do soro (LA/P1) resistiu e manteve a viabilidade de Lactobacillus acidophilus (9,57 log CFU / g-1). A melhor viabilidade foi obtida no armazenamento a -18 ° C, com uma contagem de 7,86 log CFU / g-1 para essa mesma microcápsula (LA/P1) no final do armazenamento (120 dias) e 6,55 log CFU / g-1 para as microcápsulas com duas camadas de proteína do soro (LA/P3) por 105 dias. Este estudo indica que a gelificação iônica externa é eficaz e pode ser usada para a produção de microcápsulas de pectina com multicamadas de proteína de soro para promover maior proteção e viabilidade ao Lactobacillus acidophilus.

Biopolymeric In Situ Hydrogels for Tissue Engineering and Bioimaging Applications

BACKGROUND: Biopolymeric in situ hydrogels play a crucial role in the regenerative repair and replacement of infected or injured tissue. They possess excellent biodegradability and biocompatibility in the biological system, however only a few biopolymeric in situ hydrogels have been approved clinically. Researchers have been investigating new advancements and designs to restore tissue functions and structure, and these studies involve a composite of biometrics, cells and a combination of factors that can repair or regenerate damaged tissue. METHODS: Injectable hydrogels, cross-linking mechanisms, bioactive materials for injectable hydrogels, clinically applied injectable biopolymeric hydrogels and the bioimaging applications of hydrogels were reviewed. RESULTS: This article reviews the different types of biopolymeric injectable hydrogels, their gelation mechanisms, tissue engineering, clinical applications and their various in situ imaging techniques. CONCLUSION: The applications of bioactive injectable hydrogels and their bioimaging are a promising area in tissue engineering and regenerative medicine. There is a high demand for injectable hydrogels for in situ imaging.

Preparation of nanogels with different gelation speeds as embolization and drug delivery materials and evaluation of their capacity / 中国药学杂志

OBJECTIVE: To design nanogels with different phase transition speeds and screen embolization and drug delivery materials that can be used for transcatheter arterial chemoembolization (TACE). METHODS: Random copolymer PNA nanogels and interpenetrating polymer PNA-IPN nanogels, in which the ratio of co-monomers between N-isopropylacrylamide (NIPAM) and acrylic acid (AA) were 3∶1, 2∶1 and 1∶1, respectively, were prepared by emulsion polymerization. The embolization and drug-loaded capacities of nanogels were evaluated by characterization of their particle morphology, temperature sensitivity, solution phase transition behavior and rheological properties. RESULTS: Nanogel particles were relatively uniform spheres. The particle size of PNA was 386-795 nm, and the particle size of PNA-IPN was 367-750 nm. The increase of temperature led to the decrease of particle size, while the increase of the ratio of the co-monomer AA caused the decrease of temperature sensitivity and gel strength of nanogels, and the increase of the phase transition temperature and the gelation speed. Compared with PNA, PNA-IPN-2 had slightly smaller particle size, lower gelation temperature, faster gelation speed and significantly increased gel strength. The PNA-IPN-2 could load doxorubicin by charge action with 10.3% of loading efficiency. CONCLUSION: The 140 mg•mL-1 PNA-IPN-2 solution has suitable gelation temperature, gelation speed and gel strength. The shearthinning nature and drug release feature are very favorable for TACE, so the PNA-IPN-2 solution is promising for the applications in TACE as nanogels embolization and drug delivery materials.

Production and characterization of alginate microparticles obtained by ionic gelation and electrostatic adsorption of concentrated soy protein / Produção e caracterização de micropartículas de alginato obtidas por gelificação iônica e adsorção eletrostática de concentrado proteico de soja

ABSTRACT: Microencapsulation is used for protection and release of bioactive compounds. Combination of encapsulation methods allows the production of matrices with better technological properties compared to the application of one of the methods alone. Use of ionic gelation produces porous microparticles, and coating it with a protein, by electrostatic interaction, may contribute to a better protection of the active compound. The objective of the research was to produce alginate microparticles (AG) through ionic gelation and to coat them with soluble protein from soy protein concentrate. Two factors were studied, calcium concentration during ionic gelation (0.8, 1.6 and 2.4% w/w) and pH (3.5 and 7.0) of the protein solution for electrostatic interaction. Zeta potential (ZP) of biopolymers and microparticles were determined. Microparticles were characterized according to its morphology, average size and size distribution, as well as protein adsorption. Microparticles presented (154-334μm) multinuclear distribution of active compound, continuous and smooth surface, with a great standard deviation considering average size. The calcium concentration did not influence the protein adsorption on microparticles.The pH used in protein adsorption showed significant effect, with higher adsorption occurring at pH 3.5 (6.5 to 6.7% w/w, dry basis,db, of adsorbed protein) compared to pH 7.0 (<2.0% w/w, db, of adsorbed protein) indicating that electrostatic interaction was determinant for the protein coating. At this situation, ionic gelation microparticles and proteins presented ZP with opposite charges (pH>pKa AG<Isoelectric point, IP).

RESUMO: A microencapsulação é utilizada para a proteção de compostos bioativos e controle de sua liberação. A combinação de métodos de encapsulação permite a obtenção de matrizes com melhores propriedades tecnológicas em relação às técnicas utilizadas individualmente. Na gelificação iônica são produzidas micropartículas porosas, e o recobrimento por interação eletrostática com uma proteína permite a obtenção de micropartículas mais protetivas. O objetivo do trabalho foi produzir micropartículas de alginato (AG) através da gelificação iônica e recobri-las com proteínas solúveis de concentrado proteico de soja. Dois fatores foram estudados, o teor de cálcio utilizado na gelificação iônica (0,8,1,6 e 2,4% m/m) e o pH (3,5 e 7,0) para o recobrimento eletrostático com uma camada proteica. Os potenciais zeta (PZ) dos biopolímeros e das micropartículas foram determinados. As micropartículas foram caracterizadas quanto a morfologia, tamanho médio e sua distribuição e quanto ao teor de proteína adsorvida nas situações estudadas. As micropartículas obtidas apresentaram-se (154-334μm) com recheio distribuído de forma multinuclear, com superfície continua e visualmente lisas, porém com variação grande no tamanho médio. A variação do teor de cálcio não foi significativa na adsorção proteica. O pH utilizado na adsorção proteica foi significativo, com adsorções muito maiores em pH 3,5 (6,5 - 6,7% m/m de proteína adsorvida, base seca) comparado ao pH 7,0 (<2,0% m/m de adsorção proteica, base seca), indicando que a interação eletrostática foi determinante no recobrimento proteico. Nesta situação, micropartículas AG e a proteína apresentam PZ com cargas opostas (pH>pKa AG<ponto isoeletrico, PI).

Effect of KMG for bronchi arterial chemoembolization combined with RFA for the central lung cancer / 实用放射学杂志

Objective To investigate the curative effect of kelp micro gelation (KGM) for bronchi arterial chemoembolization (BACE) combined with radiofrequency ablation (RFA) for central lung cancer.Methods 60 patients pathologically confirmed as the central lung cancer were enrolled and performed with BACE+KGM after the tumor-feeding artery was confirmed.RFA was performed under local anesthesia 1 month later.1 month,3 months and 6 months after the treatments CT scan was performed to show the changes of the tumor.Tumor markers were detected by blood test 1 month before and after the treatments.Up to the end of this study.Improvements of clinical symptoms and complications were also evaluated.Results Among the 60 patients under the treatment of BACE+KMG+RFA,10 patients had a complete remission(CR),33 patients in partial remission (PR),11 patients in stable (SD) and 6 patients in progress (PD).1 month after the treatments,VEGFA,VEGFB,VEGFC,CEA,CA125 and CA19-9 were significantly decreased,with the overall reactive rate (ORR) of 71.67％,disease control rate (DCR) of 90.00％,18.33％ of no change,10.00 ％ progressing and the 2 year survival rate was 93.33 ％.Conclusion BACE+KMG combined RFA is an effective treatment for central lung cancer with better short-term and long-term effect,improving the life quality and survival time of patients significantly.

Preparation of triptolide nano liposome thermosensitive gel and its penetrability through nasal mucosa / 中草药

Objective To prepare nasal triptolide nano liposome thermosensitive gel (TP-NLS-TG) and investigate the in vitro penetrability through nasal mucosa. Methods The triptolide nanoliposomes were prepared by high pressure homogenization method, and the ratio of poloxamer 407 (P-407) and poloxamer 188 (P-188) was selected, using the azone dosage and stirring time as investigation factors. Gelation temperature (GT) and homogeneity of TG (RSD) were used as evaluation indexes, and TP-NLS-TG was prepared by optimized prescription. An isolated mucosal permeability model was established by frog abdominal skin to carry out the in vitro permeation test of TP-NLS-TG in nasal mucosa. Results The best prescription was 12% P-407, 10% P-188, and 3% azone, and swelling time was 4 h. The TP-SLN gelation temperature of the gel was 32 ℃, and the RSD was 0.005%. In the first 8 h, the cumulative infiltration volume per unit area was (9.296 3 ± 0.614 7) μg/cm2, and the release curve in line with the Higuchi mathematical model. Conclusion The triptolide nano liposome gel prepared by the optimum technology has an accurate gelling temperature, and uniform content, which has good permeability, can be absorbed through the frog skin.

Investigation of the parameters affecting the release of flurbiprofen from chitosan microspheres

ABSTRACT Flurbiprofen (FLB), a NSAID, widely used for preventing pain generally for arthritis or dental problems. In this study, FLB loaded chitosan microspheres were prepared by ionotropic gelation method. In this method, microspheres were formed by dropping chitosan solutions containing FLB into sodium alginate solutions including sodium tripolyphosphate (TPP). A variety of formulation parameters like drug:polymer ratio, drug concentration, polymer's molecular weight, polymer concentration, pH and the concentration of TPP solutions, drying method and stirring time were analyzed. The dissolution studies were performed in a shaking water bath in pH 7.4 phosphate buffer saline (PBS) at 37 °C. Laser diffractometer was used for particle size analysis, and scanning electron microscope (SEM) was used for morphological properties. Drug loading and loading efficiency were calculated by using UV spectrophotometer. The particles obtained were spherical with 0.7-1.3 mm size range, and the loading efficiency was approximately 21-79%. The dissolution studies conducted revealed that drug:polimer ratio and the polymer type and concentration affected the drug release from microspheres. It was observed that increasing the polymer concentration, polymer's molecular weight and TPP concentration decreased the FLB release from microspheres, which was according to Higuchi kinetics.

Comparative Study of Poly(L-Lactic Acid) Scaffolds Coated with Chitosan Nanoparticles Prepared via Ultrasonication and Ionic Gelation Techniques

In this study, an attempt was made to develop bi-functional constructs serving both as scaffolds and potential delivery systems for application in neural tissue engineering. The constructs were prepared in two steps. In the first step, the bulks of poly (L-lactic acid) (PLLA) in 1, 4-dioxane/water (87:13) were fabricated using liquid-liquid thermally induced phase separation technique. In the next step, the prepared bulks were coated with chitosan nanoparticles produced by two different techniques of ultrasonication and ionic gelation by grafting-coating technique. In ultrasonication technique, the chitosan solution (2 mg/mL) in acetic acid/sodium acetate buffer (90:10) was irradiated by an ultrasound generator at 20 kHz and power output of 750 W for 100 s. In ionic gelation technique, the tripolyphosphate in water solution (1 mg/mL) was added to the same chitosan solution. The physicochemical properties of the products were characterized by Scanning Electron Microscopy, Attenuated Total Reflection Fourier Transform-Infrared, liquid displacement technique, contact angle measurement, compressive and tensile tests, as well as zeta potential and particle size analysis using dynamic light scattering. Moreover, the cell proliferation and attachment on the scaffolds were evaluated through human glioblastoma cell line (U-87 MG) and human neuroblastoma cell line [BE (2)-C] culture respectively. The results showed that the samples coated with chitosan nanoparticles prepared by ultrasonication possessed enhanced hydrophilicity, biodegradation and cytocompatibility compared with pure PLLA and PLLA coated with chitosan nanoparticles prepared by ionic gelation. This study suggests successful nanoparticles-scaffold systems which can act simultaneously as potential delivery systems and tissue engineering scaffolds.

Preparation and characterization of epigallocatechin-3-gallate chitosan nanoparticles / 中草药

Objective: To prepare the epigallocatechin-3-gallate (EGCG) chitosan nanoparticles (CS-NPs) and investigate their physicochemical properties. Methods: The EGCG-CS-NPs were prepared by ion gelation method. The formulation variables were optimized by Box-Behnken Design (BBD) of response surface methodology (RSM) of CS concentration (X1), sodium tripolyphosphate concentration (X2), and EGCG concentration (X3) as independent variables and encapsulation efficiency (Y1,%) and particle size (Y2, nm) as dependent variables. The optimized CS-NPs were characterized for encapsulation efficiency (EE), particle size, Zeta potential, morphology, and in vitro drug release behavior of EGCG-CS-NPs were studied. Results: An optimal EGCG-CS-NPs consisting of CS concentration as 2.6 g/L, sodium tripolyphosphate concentration as 1.5 g/L and EGCG concentration as 2.7 g/L. For EE, particle size, Zeta potential of EGCG-CS-NPs were found to be (85.8±3.1)%, (102.2±27.1) nm, and (25.5±4.1) mV, respectively. The CS-NPs were found to be small and spherical as seen in transmission electron microscopy (TEM). The in vitro release data proved that the drug release was steady within 24 h (pH 4.5 PBS). Conclusion: Through optimizing the formulation, we obtain the uniform EGCG-CS-NPs with in vitro sustained-release behavior. This work is useful for the further research on pharmacodynamics of EGCG-CS-NPs.

Chitosan nanoparticles loaded antibiotics as drug delivery biomaterial.

Herein we describe the preparation, characterization and utilization of chitosan nanoparticles for the intracellular delivery of the poorly cell-penetrating antibiotic e.g. Ciprofloxacin, Chlortetracycline hydrochloride and Gentamycin sulfate to improve their treatment of bacterial infections. Chitosan nanoparticles were prepared via the ionic gelation of chitosan with tri polyphosphate anions. Several parameters were studied to optimize the particle size of chitosan nanoparticles, here we select the concentration of chitosan and the concentrations of sodium tri poly phosphate (TPP) as optimizing parameters and the other factors stay constant such as pH of solution and ultrasonication time. Chitosan nanoparticles formed characterized by using FT-IR and transmission electron microscope (TEM). Results show that chitosan nanoparticles and its loaded antibiotics kill and inhibits the growth of gram (+) and gram (-) bacteria tested due to nanoparticles structures, and the antibacterial activity increased with increasing the anti biotic content.

Development and Evaluation of Chitosan Based Polymeric Nanoparticles of an Antiulcer Drug Lansoprazole.

Objective: The development of new delivery systems for the controlled release of drugs is one of the most innovative fields of research in pharmaceutical sciences. Nanoparticles specially designed to release the drug in the vicinity of target sites. The aim of this study was to formulate and evaluate the Lansoprazole nanoparticles to improve the therapeutic efficacy of Lansoprazole by loading in nanoparticle drug delivery system. Materials and Methods: Lansoprazole loaded chitosan nanoparticles (CNP1 to CNP10) were prepared by ionotropic gelation method. The formulated nanoparticles were evaluated for external morphological characters, determination of particle size analysis, zeta potential, drug content, entrapment efficiency and in-vitro release studies. Results: The drug content for the Lansoprazole loaded chitosan nanoparticles varied from 69.5±7.2% to 87.9±1.2%. The entrapment efficiencies were found to be minimum and maximum of 39.3±2.6% and 85.6±1.2%, the optimum entrapment efficiency was found to be 85.3±0.8%, particle size varied from 360±12nm to 814±62nm, zeta potential values were in positive and increased from 11.2±1.2mV to 18.7±0.4mV. In-vitro release of drug follows zero order and showed sustained release behavior for a period of 24 hr. Conclusion: The study demonstrated the successful preparation of sustained release polymeric nanoparticles of Lansoprazole.

Preparation,formulation optimization and preliminary pharmacodynamic experi-ment of insulin-loaded N-trimethyl chitosan nanoparticles / 药学实践杂志

Objective To prepare and optimize insulin-loaded N-trimethyl chitosan nanoparticles via orthogonal design , and preliminarily study the effects on blood glucose level .Methods The insulin-loaded N-trimethyl chitosan nanoparticles (INS-NPs) were prepared by ionic gelation ,and the optimal proportion was obtained with orthogonal design .The nanoparticles were characterized by transmission electron microscopy and zeta/sizer nano analyzer .The entrapment efficiency of insulin-load-ed nanoparticles and the in vitro releasing characteristics were studied by HPLC .A preliminary pharmacodynamic study of the insulin-loaded nanoparticles was also carried out .Results The INS-NPs exhibited narrow distribution .The mean diameter of INS-NPs was (63 .26 ± 1 .88)nm ,while the entrapment efficiency was (37 .92 ± 2 .11)% .After 8 hours of subcutaneous injec-tion of the INS-NPs ,the blood glucose level in diabetic rats decreased to normal level and kept stable .Conclusion The opti-mized insulin-loaded nanoparticles had homogeneous spherical shape ,small size ,and could be a new approach of administration for insulin .

Fabrication and Characterization of Gliclazide Loaded Microcapsules

This study aimed to formulate, characterize and evaluate the Gliclazide (GLZ) microcapsules prepared with sodium alginate, guar gum and pectin in different ratios by ionotropic-gelation method. The microcapsules were evaluated against different parameters such as particle size and shape, Carr's index, Hausner's ratio, rheological studies and drug release kinetics. Fourier Transform Infra Red (FTIR) and Differential Scanning Calorimetric (DSC) studies demonstrated the absence of any drug - polymers interaction. Promising characteristics were observed in rheological behavior and release kinetics. The size of microcapsules and percentage yield was in the range of 676 to 727 µm and 69 to 77%, respectively. Scanning electron micrographs revealed that microcapsules were discrete, spherical and free flowing. Entrapment efficiency and uniform drug release kinetics were some of the probable characteristics depicting the novel formulation design of Gliclazide microcapsules.