scholarly journals α-Tocopherol loaded thermosensitive polymer nanoparticles: preparation, in vitro release and antioxidant properties

Polímeros ◽  
2016 ◽  
Vol 26 (4) ◽  
pp. 304-312 ◽  
Author(s):  
Cirley Quintero ◽  
Ricardo Vera ◽  
Leon Dario Perez
Keyword(s):  
Antioxidant Properties ◽  
In Vitro Release ◽  
Polymer Nanoparticles ◽  
Thermosensitive Polymer ◽  
Vitro Release

scholarly journals Evaluation of physicochemical and antioxidant properties of nanosized copolymeric micelles loaded with kaempferol

Pharmacia ◽  
2020 ◽  
Vol 67 (2) ◽  
pp. 49-54
Author(s):  
Krassimira Yoncheva ◽  
Nadia Hristova-Avakumova ◽  
Vera Hadjimitova ◽  
Trayko Traykov ◽  
Petar Petrov
Keyword(s):  
Antioxidant Activity ◽  
Propylene Oxide ◽  
Encapsulation Efficiency ◽  
Antioxidant Properties ◽  
In Vitro Release ◽  
Before And After ◽  
Poly Propylene ◽  
Vitro Release

The study was focused on the evaluation of two copolymers as micellar carriers for kaempferol delivery. The copolymers comprised identical hydrophilic blocks of poly(2-(dimethylamino)ethyl methacrylate and different hydrophobic blocks of either poly(ε-caprolactone) (PDMAEMA9-b-PCL70-b-PDMAEMA9) or poly(propylene oxide) (PDMAEMA13-b-PPO69-b-PDMAEMA13). The calculation of Flory-Huggins parameters and determination of encapsulation efficiency showed that PDMAEMA-b-PCL-b-PDMAEMA copolymer possessed higher capacity for kaempferol loading. The diameter of the micelles before and after lyophilization was not changed, suggesting that the micelles could be lyophilized and redispersed before administration. The in vitro release of kaempferol from PDMAEMA-b-PPO-b-PDMAEMA micelles was faster than the release from PDMAEMA-b-PCL-b-PDMAEMA micelles, probably due to the higher affinity of kaempferol to this copolymer. Further, the higher affinity resulted in a retention of antioxidant activity of kaempferol in the presence of DPPH and KO2 radicals. Thus, PDMAEMA-PCL-PDMAEMA was considered more appropriate carrier because of the higher encapsulation efficiency and preservation of antioxidant activity of the drug.

scholarly journals Microfluidic encapsulation of SN-38 in block copolymer nanoparticles: effect of hydrophobic block composition on loading and release properties

2019 ◽  
Vol 97 (5) ◽  
pp. 337-343
Author(s):  
Danica Jensen ◽  
Yimeng Cao ◽  
Changhai Lu ◽  
Jeremy E. Wulff ◽  
Matthew G. Moffitt
Keyword(s):  
Release Kinetics ◽  
In Vitro Release ◽  
Polymer Nanoparticles ◽  
Amphiphilic Block Copolymers ◽  
Poly Ethylene Oxide ◽  
Rigid Rod ◽  
Poly Ethylene ◽  
20 Nm ◽  
Vitro Release

A gas–liquid microfluidic reactor was used to prepare polymer nanoparticles (PNPs) containing the drug 7-ethyl-10-hydroxy camptothecin (SN-38) from a series of poly(methyl caprolactone-co-caprolactone)-b-poly(ethylene oxide) (P(MCL-co-CL)-b-PEO) amphiphilic block copolymers with variable MCL content in the hydrophobic block. All three copolymers formed spheres with ∼20 nm core diameters by TEM, although some rigid rod-like aggregates were also formed by the PMCL-50 and PMCL-75 copolymers. SN-38 encapsulation efficiencies (EE = 2.7%–3.0%) and loading levels (DL = 2.0%–2.9%) were similar for the three copolymers. In vitro release kinetics became significantly slower as the MCL content increased, with release half times increasing monotonically from 3.4 to 6.2 h as the MCL content of the hydrophobic block increased from 50% to 100%. The ability to systematically tune release half times via controlled variation in the hydrophobic block composition, while maintaining constant PNP size and loading levels, represents an intriguing chemical handle for the optimization of SN-38 nanomedicines.

Study on in vitro release patterns of fentanyl-loaded PLGA microspheres

2003 ◽  
Vol 20 (5) ◽  
pp. 569-579 ◽  
Author(s):  
S.-A. Seo ◽  
G. Khang ◽  
J. M. Rhee ◽  
J. Kim ◽  
H. B. Lee
Keyword(s):  
In Vitro Release ◽  
Plga Microspheres ◽  
Vitro Release

Reliability of a Single β-Thromboglobulin Measurement in a Diabetic Population : Importance of PGE1 in Anticoagulant Mixture

1987 ◽  
Vol 57 (02) ◽  
pp. 201-204 ◽  
Author(s):  
P Y Scarabin ◽  
L Strain ◽  
C A Ludlam ◽  
J Jones ◽  
E M Kohner
Keyword(s):  
In Vitro Release ◽  
Mean Value ◽  
Reliable Estimate ◽  
Diabetic Patients ◽  
Single Measurement ◽  
Diabetic Population ◽  
The Difference ◽  
Vitro Release

SummaryDuring the collection of samples for plasma β-thromboglobulin (β-TG) determination, it is well established that artificially high values can be observed due to in-vitro release. To estimate the reliability of a single β-TG measurement, blood samples were collected simultaneously from both arms on two separate occasions in 56 diabetic patients selected for a clinical trial. From each arm, blood was taken into two tubes containing an anticoagulant mixture with (tube A) and without (tube B) PGE!. The overall mean value of B-TG in tube B was 1.14 times higher than in tube A (p <0.01). The markedly large between-arms variation accounted for the most part of within-subject variation in both tubes and was significantly greater in tube B than in tube A. Based on the difference between B-TG values from both arms, the number of subjects with artifically high B-TG values was significantly higher in tube B than in tube A on each occasion (overall rate: 28% and 14% respectively). Estimate of between-occasions variation showed that B-TG levels were relatively stable for each subject between two occasions in each tube. It is concluded that the use of PGEi decreases falsely high B-TG levels, but a single measurement of B-TG does not provide a reliable estimate of the true B-TG value in vivo.

Preparation and In-vitro Evaluation of Fe3O4 Encapsulated by Chitosan Loaded Capecitabine Nanoparticles for the Treatment of Breast Cancer

2016 ◽  
Vol 6 (3) ◽  
Author(s):  
Shanmuganathan S. ◽  
Nigma S. ◽  
Anbarasan B. ◽  
Harika B.
Keyword(s):  
Fe3o4 Nanoparticles ◽  
Polymer Concentration ◽  
In Vitro Release ◽  
Entrapment Efficiency ◽  
In Vitro Evaluation ◽  
Sem Image ◽  
Therapeutic Molecules ◽  
Dialysis Method ◽  
Vitro Release

Nanoparticulate Carriers which is biodegradable, biocompatible and bio adhesive have significant feasible applications for administration of therapeutic molecules. The present study was aimed to formulate and optimise Capecitabine loaded Chitosan-Fe3O4 Nanoparticles and to study the in-vitro evaluation by sigma dialysis method. Capecitabine loaded chitosan – Fe3O4 nanoparticles batches with different ratios of drug: polymer (1:1, 1:2, 1:3, 1:4, 1:5, 1:6) were prepared by ionic gelation method. Increase in polymer concentration increases the nanoparticle drug content. Entrapment efficiency was 60.12% with drug to polymer ratio F3 (1:3). In-vitro release was found to be 65.20% for 12 hrs. Capecitabine from chitosanFe3O4 nanoparticles SEM image reveals discrete spherical structure and particles with size range of 100-500nm. FTIR studies represent the functional groups present with no characteristics change in formulations. Samples stored at refrigerator conditions showed better stability compared with samples kept at other conditions during 8 weeks of storage.

Formulation and In-vitro Evaluation of Chewable Tablets of Montelukast Sodium

2015 ◽  
Vol 5 (3) ◽  
Author(s):  
Laxman Devkota ◽  
Bhupendra Poudel ◽  
Junu Silwal
Keyword(s):  
In Vitro Release ◽  
Magnesium Stearate ◽  
Physical Parameters ◽  
Artificial Sweetener ◽  
Leukotriene Receptor Antagonist ◽  
Montelukast Sodium ◽  
Chewable Tablets ◽  
Leukotriene Receptor ◽  
Vitro Release

The objective of the present study is to develop chewable tablets containing different pharmaceutical compositions with simple manufacturing procedures using different excipients. Mannitols, L-HPC 11, Aspartame, Crospovidone, Crospovidone, Aerosil, and Magnesium Stearate are used as excipients for effective formulation of anti-asthmatic drug Montelukast. Montelukast is a selective, orally acting leukotriene receptor antagonist that is used for the treatment of asthma and seasonal allergic rhinitis. Montelukast chewable tablets were prepared by Direct Compression methods using suitable excipients. The chewable tablets were better presented using artificial sweetener Aspartame as flavouring agent. A total of forteen formulations were prepared and the granules were evaluated for pre-compression parameters. The formulated tablets were evaluated for post-compression parameters .The results showed that all the physical parameters were within the acceptable limits. The in vitro release study of all the formulations showed good release. The study concludes that aforementioned excipients can be used to design chewable montelukast sodium tablets.

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