Preparation and characterization of N-benzyl-N,O-succinyl chitosan polymeric micelles for solubilization of poorly soluble non-steroidal anti-inflammatory drugs

Purpose: To investigate the solubilization of poorly water-soluble non-steroidal  anti-inflammatory drugs (NSAIDs) in N-benzyl-N,O-succinyl chitosan (BSCS)  polymeric micellesMethods: BSCS was synthesized by reductive amination and succinylation,  respectively. NSAIDs; meloxicam (MX), piroxicam (PRX), ketoprofen (KP) and indomethacin (IND) were entrapped in the hydrophobic inner cores by evaporation method. The effects of drug structure on loading efficiency, particle size and surface charge of micelles were investigated.Results: The critical micelle concentration of BSCS micelles was 0.0385 mg/mL and cytotoxicity on Caco-2 cells depends on the polymer concentration (IC50 = 3.23 ± 0.08 mg/mL). BSCS micelles were able to entrap MX, PRX, KP and IND and also improve the solubility of drugs. Drug loading efficiency was highly dependent on the drug molecules. The drug loading capacity of these BSCS micelles was in the following rank order: KP (282.9 μg/mg) > PRX (200.8 μg/mg) > MX (73.7 μg/mg) > IND (41.2 μg/mg). The highest loading efficiency was observed in KP-loaded BSCS micelles due to the attractive force between phenyl groups of KP and benzyl groups of the polymer. Particle size and surface charge were in the range of 312 - 433 nm and -38 to -41 mV, respectively.Conclusion: BSCS copolymer presents desirable attributes for enhancing the  solubility of hydrophobic drugs. Moreover, BSCS polymeric micelles might be beneficial carrier in a drug delivery system.Keywords: BSCS, polymeric micelles, solubilization, non-steroidal anti-inflammatory drug

Additive effects on cotton dyeing with dye extract from achiote seeds

466-474Cotton yarns have been pretreated with the additives, such as chitosan, microcrystalline chitosan, quaternized chitosan & aqueous extract from the fruit of Diospyros mollis Griff, as well as with the commercial formaldehyde-free cationic fixing agent (Sera® Fast C-NC) & alum (post-mordanting), and their dyeing fastness properties are studied. These treated cotton yarns are then dyed with the annatto dye extract from Bixa orellana L. (Achiote) seeds and tested for different properties including K/S value, light fastness, and wash fastness. Pre-treatment of cotton yarn with chitosan or microcrystalline chitosan solution (together with glyoxal cross-linking) or quaternized chitosan, or Sera® Fast C-NC before dyeing, shows a better color depth (K/S) and improved wash fastness properties in comparison to yarn with alum post-mordanting and the untreated cotton yarn. Improved light fastness is also obtained on inclusion of the anti-oxidant ascorbic acid in the post-treatment protocol. These additive treatments thus offer considerable potential for the improved annatto dyeing of cotton

Additive effects on cotton dyeing with dye extract from achiote seeds

2019, National Institute of Science Communication and Information Resources (NISCAIR). All rights reserved. Cotton yarns have been pretreated with the additives, such as chitosan, microcrystalline chitosan, quaternized chitosan & aqueous extract from the fruit of Diospyros mollis Griff, as well as with the commercial formaldehyde-free cationic fixing agent (Sera® Fast C-NC) & alum (post-mordanting), and their dyeing fastness properties are studied. These treated cotton yarns are then dyed with the annatto dye extract from Bixa orellana L. (Achiote) seeds and tested for different properties including K/S value, light fastness, and wash fastness. Pre-treatment of cotton yarn with chitosan or microcrystalline chitosan solution (together with glyoxal cross-linking) or quaternized chitosan, or Sera® Fast C-NC before dyeing, shows a better color depth (K/S) and improved wash fastness properties in comparison to yarn with alum post-mordanting and the untreated cotton yarn. Improved light fastness is also obtained on inclusion of the anti-oxidant ascorbic acid in the post-treatment protocol. These additive treatments thus offer considerable potential for the improved annatto dyeing of cotton

Validated HPLC method for simultaneous quantitative determination of dimethylcurcumin and resveratrol in pluronic-F127 nanomicelles: Formulation with enhanced anticancer efficacy

Nano-micelles offer a promising vehicle for the delivery various therapeutically significant biologicals. Development of convenient and efficient chromatographic methods for the quantitative determination of the active pharmaceutical ingredients in such systems is of immense importance. In this study pluronic-F-127 nano-micelles were prepared and loaded with dimethylcurcumin (DMC) and resveratrol (Res). A simple, convenient and effective HPLC method was developed for the quantitative estimation of DMC and Res in the polymeric nano-micelles through a single injection. A reverse-phase ACE® C18 column (250 mm × 4.6 mm) was used with a gradient mobile phase system consisting of 1 % MeOH and 0.1 % H3PO4:100 % acetonitrile at 1 mL/min flow rate with UV detection for Res, and fluorescence detector for DMC. The calibration curves generated for both the compounds were found linear with r2 values of 1.000 over a concentration range of 2–25 µg/mL with low limit of detection (LOD) values of 0.37 and 0.16 µg/mL for DMC and Res respectively and limit of quantification (LOQ) values of 1.23 and 0.55 µg/mL for DMC and Res respectively. Similarly, accuracy was found in a range of 98.80 -102.47 % for DMC and 100.58–101.77 % for Res. Furthermore, the within-run precisions (%RSD) were 0.073 - 0.444% for DMC and 0.159 - 0.917% for Res, while between-run precisions (%RSD) were 0.344 - 1.47 for DMC and 0.458 - 1.651 for Res. Moreover, the DMC with Res co-loaded nanomicelles showed higher activity against MCF-7 and MDA-MB 231 compared to DMC and Res alone. Overall, this study presented a simple, convenient, precise and accurate method for the quantitative determination of DMC and Res in polymeric nano-micelles which have anticancer potential. • A simple HPLC for the quantitative determination of DMC and Res in nanomicelles having anti-cancer potential. • Non complicate with high degree of recoveries of sample preparation process. • This method can be used to determine a mixture of DMC and Res in pharmaceutical formulation in single injection

A kinetic and thermodynamic study of lac dye adsorption on silk yarn coated with microcrystalline chitosan

The coating of silk yarn with microcrystalline chitosan (MCCh) was carried out using the ultrasonic-assisted method at a pulsed wave frequency of 80 kHz, which only had a slight impact on the yarn as measured by changes in Young\u27s modulus and percentage of elongation compared with untreated silk. A significant enhancement of lac dye uptake onto MCCh-coated silk yarn compared with the untreated silk was observed. The rate of dye uptake at different temperatures onto silk yarn coated with MCCh was investigated. It was found that the adsorption rate constant and diffusion coefficient both increased with increasing temperature, as a result of a diffusion kinetically controlled process with a diffusion activation energy of 9.40 kJ mol −1 . This suggests that dye adsorption on silk yarn coated with MCCh is a physisorption process. The free energy change (∆G ○ ), enthalpy change (∆H ○ ) and entropy change for dye adsorption were also determined, and the negative values of ∆G ○ and ∆H ○ obtained indicated that the lac dye adsorption process is both spontaneous and exothermic

Oral Methylated N-Aryl Chitosan Derivatives for Inducing Immune Responses to Ovalbumin

Purpose: To investigate different structures of modified chitosan containing different chain lengths and aromatic moieties for vaccine delivery capacity. Methods: The characteristics of the modified chitosan, namely, methylated N-(4-N,Ndimethylaminobenzyl) chitosan (TM-Bz-CS), methylated N-(4-N,N-dimethylaminocinnamyl) chitosan (TM-CM-CS) and methylated N-(4-pyridinylmethyl) chitosan (TM-Py-CS), with Eqiva degree (equivalent degree) were studied by in vitro absorption enhancement on the transepithelial electrical resistance (TEER) in Caco-2 cell monolayers as well as by in vivo adjuvant activity against ovalbumin (OVA), a model antigen, via oral administration to BALB/c mice. Results: At the same concentration and pH (0.1 mg/ml, pH 7.4), TM65CM50CS exhibited the highest in vitro enhancing paracellular permeability and also the highest in vivo adjuvant activity following oral administration to mice. OVA-specific serum immunoglobulin G (IgG) antibody levels of mice that received OVA in TM65CM50CS were significantly (p < 0.05) higher than those that received OVA in TM65CS, TM56Bz42CS and TM53Py40CS. On the other hand, TM65CS and TM56Bz42CS exhibited in vitro enhancing paracellular permeability but showed no immune responses, while TM53Py40CS failed to enhance paracellular permeability and did not elicit immune responses as well. Conclusion: This study demonstrates that addition of hydrophobic moiety (dimethylaminocinnamyl) to CS backbone can increase both its absorption enhancing property and adjuvant activity. The chemical structure and the positive charge location play an important role for binding affinity, absorption enhancement and immune responses