scholarly journals Probing Critical Physical Properties of Lactose-Polyethylene Glycol Microparticles in Pulmonary Delivery of Chitosan Nanoparticles

Pharmaceutics ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1581
Author(s):  
Nasser Alhajj ◽  
Idanawati Naharudin ◽  
Paolo Colombo ◽  
Eride Quarta ◽  
Tin Wui Wong

Pulmonary delivery of chitosan nanoparticles is met with nanoparticle agglomeration and exhalation. Admixing lactose-based microparticles (surface area-weighted diameter~5 μm) with nanoparticles mutually reduces particle agglomeration through surface adsorption phenomenon. Lactose-polyethylene glycol (PEG) microparticles with different sizes, morphologies and crystallinities were prepared by a spray drying method using varying PEG molecular weights and ethanol contents. The chitosan nanoparticles were similarly prepared. In vitro inhalation performance and peripheral lung deposition of chitosan nanoparticles were enhanced through co-blending with larger lactose-PEG microparticles with reduced specific surface area. These microparticles had reduced inter-microparticle interaction, thereby promoting microparticle–nanoparticle interaction and facilitating nanoparticles flow into peripheral lung.

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Kumi Kawano ◽  
Yoshie Maitani

The folate receptor is an attractive target for selective tumor delivery of liposomal doxorubicin (DXR) because it is abundantly expressed in a large percentage of tumors. This study examined the effect of polyethylene glycol (PEG) spacer length and folate ligand density on the targeting ability of folate-modified liposomes. Liposomes were modified with folate-derivatized PEG-distearoylphosphatidylethanolamine with PEG molecular weights of 2000, 3400, or 5000. The association of DXR-loaded liposomes with KB cells, which overexpress the folate receptor, was evaluated by flow cytometry at various ratios of folate modification. A low ratio of folate modification with a sufficiently long PEG chain showed the highest folate receptor-mediated association with the cells, but did not show the highest in vitro cytotoxicity. DXR release from folate-modified liposomes in endosomes might be different. These findings will be useful for designing folate receptor-targeting carriers.


1995 ◽  
Vol 73 (05) ◽  
pp. 805-811 ◽  
Author(s):  
Yasuo Takahashi ◽  
Yoshitaka Hosaka ◽  
Hiromi Niina ◽  
Katsuaki Nagasawa ◽  
Masaaki Naotsuka ◽  
...  

SummaryWe examined the anticoagulant activity of two major molecules of soluble thrombomodulin purified from human urine. The apparent molecular weights of these urinary thrombomodulins (UTMs) were 72,000 and 79,000, respectively. Both UTMs showed more potent cofactor activity for protein C activation [specific activity >5,000 thrombomodulin units (TMU)/mg] than human placental thrombomodulin (2,180 TMU/mg) and rabbit lung thrombomodulin (1,980 TMU/mg). The UTMs prolonged thrombin-induced fibrinogen clotting time (>1 TMU/ml), APTT (>5 TMU/ml), TT (>5 TMU/ml) and PT (>40 TMU/ml) in a dose-dependent fashion. These effects appeared in the concentration range of soluble thrombomodulins present in human plasma and urine. In the rat DIC model induced by thromboplastin, administration of UTMs by infusion (300-3,000 TMU/kg) restored the hematological abnormalities derived from DIC in a dose-dependent fashion. These results demonstrate that UTMs exhibit potent anticoagulant and antithrombotic activities, and could play a physiologically important role in microcirculation.


1964 ◽  
Vol 12 (01) ◽  
pp. 232-261 ◽  
Author(s):  
S Sasaki ◽  
T Takemoto ◽  
S Oka

SummaryTo demonstrate whether the intravascular precipitation of fibrinogen is responsible for the toxicity of heparinoid, the relation between the toxicity of heparinoid in vivo and the precipitation of fibrinogen in vitro was investigated, using dextran sulfate of various molecular weights and various heparinoids.1. There are close relationships between the molecular weight of dextran sulfate, its toxicity, and the quantity of fibrinogen precipitated.2. The close relationship between the toxicity and the precipitation of fibrinogen found for dextran sulfate holds good for other heparinoids regardless of their molecular structures.3. Histological findings suggest strongly that the pathological changes produced with dextran sulfate are caused primarily by the intravascular precipitates with occlusion of the capillaries.From these facts, it is concluded that the precipitates of fibrinogen with heparinoid may be the cause or at least the major cause of the toxicity of heparinoid.4. The most suitable molecular weight of dextran sulfate for clinical use was found to be 5,300 ~ 6,700, from the maximum value of the product (LD50 · Anticoagulant activity). This product (LD50 · Anticoagulant activity) can be employed generally to assess the comparative merits of various heparinoids.5. Clinical use of the dextran sulfate prepared on this basis gave satisfactory results. No severe reaction was observed. However, two delayed reactions, alopecia and thrombocytopenia, were observed. These two reactions seem to come from the cause other than intravascular precipitation.


1979 ◽  
Vol 42 (05) ◽  
pp. 1630-1633 ◽  
Author(s):  
A G Castle ◽  
N Crawford

SummaryBlood platelets contain microtubule proteins (tubulin and HMWs) which can be polymerised “in vitro” to form structures which resemble the microtubules seen in the intact platelet. Platelet tubulin is composed of two non-identical subunits a and p tubulin which have molecular weights around 55,000 but can be resolved in alkaline SDS-polyacrylamide gel electrophoresis. These subunits associate as dimers with sedimentation coefficients of about 5.7 S although it is not known whether the dimer protein is a homo- or hetero-dimer. The dimer tubulin binds the anti-mitotic drug colchicine and the kinetics of this binding are similar to those reported for neurotubulins. Platelet microtubules also contain two HMW proteins which appear to be essential and integral components of the fully assembled microtubule. These proteins have molecular weights greater than 200,000 daltons. Fluorescent labelled antibodies to platelet and brain tubulins stain long filamentous microtubular structures in bovine lens epithelial cells and this pattern of staining is prevented by exposing the cells to conditions known to cause depolymerisation of cell microtubules.


Author(s):  
Sudhakar Sekar ◽  
Shee Sim May

The aim of the study is to formulate a modified release chitosan nanoparticles for the oral delivery of atorvastatin and to study the in vitro release of atorvastatin from chitosan nanoparticles. Atorvastatin-loaded chitosan nanoparticles were prepared with different concentration of cross-linking agent (glutaraldehyde) by emulsion interfacial reaction method. The formed nanoparticles were characterized in terms of size and morphological characteristics by scanning electron microscopy (SEM) and transmission electron microscope (TEM). Spherical and regular nanoparticles with the size range of 100-250nm were formed. Atorvastatin encapsulation efficiency of nanoparticles was found to be highest in ANP3, followed by ANP2 and ANP1. The in vitro release of atorvastatin was studied by membrane diffusion technique. The resulted cumulative percentage of drug released for ANP1, ANP2 and ANP3 were 60.08%, 34.81% and 20.39% respectively. Through this study, the nanoparticles preparation technique has shown to be a promising approach for enhancing the dissolution of hydrophobic drugs like atorvastatin calcium. The application of this novel delivery system offers good therapeutic potential in the management of hypercholesterolemia and dyslipidemia.


2020 ◽  
Vol 15 ◽  
Author(s):  
Manasi M. Chogale ◽  
Sujay S. Gaikwad ◽  
Savita P. Kulkarni ◽  
Vandana B. Patravale

Background: Tuberculosis (TB) continues to be among the leading causes for high mortality among developing countries. Though a seemingly effective treatment regimen against TB is in place, there has been no significant improvement in the therapeutic rates. This is primarily owing to the high drug doses, their associated sideeffects, and prolonged treatment regimen. Discontinuation of therapy due to the severe side effects of the drugs results in the progression of the infection to the more severe drug-resistant TB. Objectives: Reformulation of the current existing anti TB drugs into more efficient dosage forms could be an ideal way out. Nanoformulations have been known to mitigate the side effects of toxic, high-dose drugs. Hence, the current research work involves the formulation of Isoniazid (INH; a first-line anti TB molecule) loaded chitosan nanoparticles for pulmonary administration. Methods: INH loaded chitosan nanoparticles were prepared by ionic gelation method using an anionic crosslinker. Drugexcipient compatibility was evaluated using DSC and FT-IR. The formulation was optimized on the principles of Qualityby-Design using a full factorial design. Results: The obtained nanoparticles were spherical in shape having an average size of 620±10.97 nm and zeta potential +16.87±0.79 mV. Solid state characterization revealed partial encapsulation and amorphization of INH into the nanoparticulate system. In vitro release study confirmed an extended release of INH from the system. In vitro cell line based safety and efficacy studies revealed satisfactory results. Conclusion: The developed nanosystem is thus an efficient approach for antitubercular therapy.


2019 ◽  
Vol 9 (2) ◽  
pp. 89-96
Author(s):  
Abbaraju Krishna Sailaja ◽  
Juveria Banu

Aim: The aim of this investigation was to develop and characterize naproxen loaded chitosan nanoparticles by emulsion interfacial reaction method. Methodology: For emulsion interfacial reaction method chitosan was used as a polymer. In this method, eight formulations were prepared by varying drug to polymer concentration. Discussion: Out of eight formulations prepared using emulsion interfacial reaction method EI8 formulation was found to be the best formulation. The drug content was observed as 94.4%, entrapment efficiency and loading capacity were found to be 87.5% and 75%, respectively. The mean particle diameter was measured as 324.6nm and the Zeta potential value was found to be -42.4mv. In vitro drug release data showed 97.2% of drug release rate sustained up to 12hrs. Conclusion: The results clearly reveal that EI8 formulation having the highest amount of drug was considered as the best formulation because of its small mean particle diameter, good entrapment efficiency, and stability.


2015 ◽  
Vol 1718 ◽  
pp. 97-102 ◽  
Author(s):  
Toralf Roch ◽  
Konstanze K. Julich-Gruner ◽  
Axel T. Neffe ◽  
Nan Ma ◽  
Andreas Lendlein

ABSTRACTPolymer-based therapeutic strategies require biomaterials with properties and functions tailored to the demands of specific applications leading to an increasing number of newly designed polymers. For the evaluation of those new materials, comprehensive biocompatibility studies including cyto-, tissue-, and immunocompatibility are essential. Recently, it could be demonstrated that star-shaped amino oligo(ethylene glycol)s (sOEG) with a number average molecular weight of 5 kDa and functionalized with the phenol-derived moieties desaminotyrosine (DAT) or desaminotyrosyl tyrosine (DATT) behave in aqueous solution like surfactants without inducing a substantial cytotoxicity, which may qualify them as solubilizer for hydrophobic drugs in aqueous solution. However, for biomedical applications the polymer solutions need to be free of immunogenic contaminations, which could result from inadequate laboratory environment or contaminated starting material. Furthermore, the materials should not induce uncontrolled or undesired immunological effects arising from material intrinsic properties. Therefore, a comprehensive immunological evaluation as perquisite for application of each biomaterial batch is required. This study investigated the immunological properties of sOEG-DAT(T) solutions, which were prepared using sOEG with number average molecular weights of 5 kDa, 10 kDa, and 20 kDa allowing analyzing the influence of the sOEG chain lengths on innate immune mechanisms. A macrophage-based assay was used to first demonstrate that all DAT(T)-sOEG solutions are free of endotoxins and other microbial contaminations such as fungal products. In the next step, the capacity of the different DAT(T)-functionalized sOEG solutions to induce cytokine secretion and generation of reactive oxygen species (ROS) was investigated using whole human blood. It was observed that low levels of the pro-inflammatory cytokines interleukin(IL)-1β and IL-6 were detected for all sOEG solutions but only when used at concentrations above 250 µg·mL-1. Furthermore, only the 20 kDa sOEG-DAT induced low amounts of ROS-producing monocytes. Conclusively, the data indicate that the materials were not contaminated with microbial products and do not induce substantial immunological adverse effectsin vitro,which is a prerequisite for future biological applications.


Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2644
Author(s):  
Jan Oszmiański ◽  
Sabina Lachowicz ◽  
Paulina Nowicka ◽  
Paweł Rubiński ◽  
Tomasz Cebulak

The present study aimed to evaluate the effect of Jerusalem artichoke processing methods and drying methods (freeze drying, sublimation drying, vacuum drying) on the basic physicochemical parameters, profiles and contents of sugars and polyphenolic compounds, and health-promoting properties (antioxidant activity, inhibition of the activities of α-amylase, α-glucosidase, and pancreatic lipase) of the produced purée. A total of 25 polyphenolic compounds belonging to hydroxycinnamic phenolic acids (LC-PDA-MS-QTof) were detected in Jerusalem artichoke purée. Their average content in the raw material was at 820 mg/100 g dm (UPLC-PDA-FL) and was 2.7 times higher than in the cooked material. The chemical composition and the health-promoting value of the purées were affected by the drying method, with the most beneficial values of the evaluated parameters obtained upon freeze drying. Vacuum drying could offer an alternative to freeze drying, as both methods ensured relatively comparable values of the assessed parameters.


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