scholarly journals Noyes-Whitney Dissolution Model-Based pH-Sensitive Slow Release of Paclitaxel (Taxol) from Human Hair-Derived Keratin Microparticle Carriers

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
V. W. Wimalasiri ◽  
S. P. Dunuweera ◽  
A. N. Dunuweera ◽  
R. M. G. Rajapakse
Keyword(s):  
Targeted Delivery ◽  
Human Hair ◽  
Metal Ion ◽  
Slow Release ◽  
Release Kinetics ◽  
Ph Dependence ◽  
Drug Loading ◽  
Toxic Metal ◽  
Dissolution Model ◽  
Ph Range

This paper describes a convenient and straightforward method developed to extract keratin particles (KPs) from human hair. It also involves their characterization by several methods and encapsulation of the anticancer drug Paclitaxel (Taxol) within them, aiming for targeted delivery to cancerous sites and slow release at their vicinity. The KPs obtained were in micrometer in size. They are capable of encapsulating Taxol within them with a high encapsulation efficiency of 56% and a drug loading capacity of 2.360 g of Taxol per g keratin. As revealed by the SEM elemental analysis, KPs do not contain any toxic metal ion, and hence, they pose no toxicity to human cells. The pH-dependent release kinetics of the drug from KPs indicates that the drug is released faster when the pH of the solution is increased in the 5.0 to 7.0 pH range. The release kinetics obtained is impressive, and once targeted to the cancerous sites, using cancer directing agents, such as folic acid; a glutamate urea ligand known as DUPA; aminopeptidase N, also known as CD13; and FAP-α-targeting agents, the slow release of the drug is expected to destroy only the cancerous cells. The Noyes-Whitney dissolution model was used to analyze the release behavior of Taxol from KPs, which shows excellent fitting with experimental data. The pH dependence of drug release from keratin is also explained using the 3-D structures and keratin stability at different pH values.

Therapeutic Properties of PDMS Nanoparticles: A Promising New Drug Delivery Vehicle Against Inflammatory Conditions

2021 ◽  
Vol 24 ◽  
Author(s):  
Aiswarya Anilkumar Ajitha ◽  
Sri SivaKumar ◽  
Gayathri Viswanathan ◽  
Sabulal Baby ◽  
Prabath Gopalakrishnan Biju
Keyword(s):  
Drug Delivery ◽  
Targeted Delivery ◽  
Release Kinetics ◽  
Drug Loading ◽  
Systemic Circulation ◽  
Biological Evaluation ◽  
Raw 264.7 Cells ◽  
Morphological Examination ◽  
Inflammatory Conditions ◽  
Anti Inflammatory

Background: Over the last few decades, there has been a stupendous change in the area of drug delivery using particulate delivery systems, with increasing focus on nanoparticles in recent times. Nanoparticles helps to improve and alter the pharmacodynamic properties and pharmacokinetics of various types of drug molecules. These features help to protect the drug entity in the systemic circulation, access of the drug to the chosen sites, and to deliver the drug in a controlled and sustained rate at the site of action. Objective: Nanoparticle based targeted delivery of anti-inflammatory drugs/signal modulatory agents to the cytoplasm or nuclei of the targeted cell can significantly enhance the precision and efficacy of intended therapeutic activity. To this end, we report ligand free, enhanced intra-nuclear delivery model of anti-inflammatory therapeutics via PDMS nanoparticles. Method: PDMS nanoparticles were prepared by sacrificial silica template-based approach and details of their characterization for suitability as a nanoparticle-based delivery material is detailed herein. Results: Biological evaluation for compatibility was carried out and the results showed that the PDMS nanoparticle has no toxicity on RAW 264.7 cells in the concentration range of 10, 20, 40, 60, 80, 100 and 120 μg/mL in culture. Biocompatibility and absence of toxicity was determined by morphological examination and cell viability assays. Drug loading and release kinetics were carried out with the anti-inflammatory drug Diclofenac. Conclusion: In this paper we clearly demonstrate the various aspects of nanoparticle articulation, characterization, effect of their characteristics and their applications as a non-toxic drug delivery molecule for its potential applications in therapeutic delivery of drugs for sustained release.

scholarly journals Comparative Evaluation of Bromhexine HCl Mucoadhesive Microspheres Prepared by Anionic, Cationic and Nonionic Polymers

2020 ◽  
Vol 23 (2) ◽  
pp. 117-124
Author(s):  
Sabirah Ishaque Limpa ◽  
Zahirul Islam ◽  
Md Selim Reza
Keyword(s):  
Surface Morphology ◽  
Release Kinetics ◽  
Drug Loading ◽  
Entrapment Efficiency ◽  
Pharmaceutical Journal ◽  
In Vitro Dissolution ◽  
Release Mechanism ◽  
Drug Entrapment Efficiency ◽  
Ph Range

The purpose of this study was to formulate and assess the mucoadhesive microspheres of bromhexine hydrochloride, a mucolytic agent, using three different types of polymers to achieve gastric retention for improved solubility and bioavailability of the drug. The mucoadhesive formulation was prepared because it dissolved in the pH range of 1 to 4. The characteristics of the prepared microspheres were evaluated by determining the particle size, percent drug loading, surface morphology, swelling behavior, mucoadhesive bond strength and drug entrapment efficiency. The in vitro dissolution was studied using the USP dissolution apparatus I in 0.1N HCl (pH 1.2) media for 8 hours. The release kinetics were analyzed by using zero order, first order, Higuchi, Korsmeyer-Peppas and Hixon-crowell equations to explain the release mechanism from the microspheres. The microspheres exhibited good swelling index and the drug entrapment efficiency was above 79 % for all the formulations. All the formulations showed drug release above 25%, 35%, 50% and 75% after 2 hrs, 4 hrs, 6 hrs and 8 hrs of dissolution respectively. The mucoadhesive bond was observed up to 8 hrs in acidic media. The surface morphology of the prepared microspheres was studied by Scanning Electron Microscope (SEM) and no interaction was found between drug and polymer from the FTIR study. Bangladesh Pharmaceutical Journal 23(2): 117-124, 2020

Chemical, Hr-Xrd and Spectroscopic Approaches to Short-Time Dissolution Behavior of Kaolin1tic Soils

1996 ◽  
Vol 432 ◽  
Author(s):  
N. Malengreau ◽  
G. Sposito
Keyword(s):  
Solid Phase ◽  
Release Kinetics ◽  
Ph Dependence ◽  
Significant Loss ◽  
Dissolution Behavior ◽  
X Ray Diffraction ◽  
Spin Resonance ◽  
Ph Range ◽  
Short Time ◽  
Kinetics Of

AbstractBatch experiments were conducted at varying proton concentrations on a representative tropical soil in order to investigate its dissolution behavior over a 12h period. The release kinetics of Al, Fe, Si and C were investigated over a 2 to 6 pH range. The pH-dependence exhibited a “point of minimum dissolution” at pH ≈ p.z.n.c. Light scattering measurements on supernatant solutions indicated that colloids were dispersed mainly at pH > p.z.n.c. These results suggested a two-pathway dissolution process, with organic matter playing a role in both pathways. High-resolution X-ray diffraction as well as electron spin resonance and diffuse reflectance spectroscopies, were applied to characterize solid-phase transformations in the course of dissolution. With the exception of quartz, all mineralogical phases (kaolinite, and minor phases such as Fe-, Al- and Ti-oxides) remained unchanged or were slightly affected. A significant loss of quartz (about 10% by mass) was observed after a 12h dissolution at pH 2. Minor phases might have played an important role in stabilizing kaolinite, and dissolved silica may have hindered the dissolution of minor phases.

Mesoporous Silica Molecular Sieve based Nanocarriers: Transpiring Drug Dissolution Research

2017 ◽  
Vol 23 (3) ◽  
pp. 467-480 ◽  
Author(s):  
Satyanarayan Pattnaik ◽  
Kamla Pathak
Keyword(s):  
Drug Release ◽  
Mesoporous Silica ◽  
Molecular Sieves ◽  
Release Kinetics ◽  
Drug Loading ◽  
Scale Up ◽  
Water Soluble ◽  
Drug Dissolution ◽  
Water Soluble Drugs ◽  
Loading Methods

Background: Improvement of oral bioavailability through enhancement of dissolution for poorly soluble drugs has been a very promising approach. Recently, mesoporous silica based molecular sieves have demonstrated excellent properties to enhance the dissolution velocity of poorly water-soluble drugs. Description: Current research in this area is focused on investigating the factors influencing the drug release from these carriers, the kinetics of drug release and manufacturing approaches to scale-up production for commercial manufacture. Conclusion: This comprehensive review provides an overview of different methods adopted for synthesis of mesoporous materials, influence of processing factors on properties of these materials and drug loading methods. The drug release kinetics from mesoporous silica systems, the manufacturability and stability of these formulations are reviewed. Finally, the safety and biocompatibility issues related to these silica based materials are discussed.

Exploring siRNA Umpired Nanogels: A Tale of Barrier Combating Carrier

2020 ◽  
Vol 26 (27) ◽  
pp. 3234-3250
Author(s):  
Sushil K. Kashaw ◽  
Prashant Sahu ◽  
Vaibhav Rajoriya ◽  
Pradeep Jana ◽  
Varsha Kashaw ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Biomedical Engineering ◽  
Viral Infections ◽  
Slow Release ◽  
Molecular Level ◽  
Release Kinetics ◽  
Biologically Active ◽  
Release Process ◽  
Rapid Release ◽  
Wide Range

Potential short interfering RNAs (siRNA) modulating gene expression have emerged as a novel therapeutic arsenal against a wide range of maladies and disorders containing cancer, viral infections, bacterial ailments and metabolic snags at the molecular level. Nanogel, in the current medicinal era, displayed a comprehensive range of significant drug delivery prospects. Biodegradation, swelling and de-swelling tendency, pHsensitive drug release and thermo-sensitivity are some of the renowned associated benefits of nanogel drug delivery system. Global researches have also showed that nanogel system significantly targets and delivers the biomolecules including DNAs, siRNA, protein, peptides and other biologically active molecules. Biomolecules delivery via nanogel system explored a wide range of pharmaceutical, biomedical engineering and agro-medicinal application. The siRNAs and DNAs delivery plays a vivacious role by addressing the hitches allied with chronic and contemporary therapeutic like generic possession and low constancy. They also incite release kinetics approach from slow-release while mingling to rapid release at the targets will be beneficial as interference RNAs delivery carriers. Therefore, in this research, we focused on the latest improvements in the delivery of siRNA loaded nanogels by enhancing the absorption, stability, sensitivity and combating the hindrances in cellular trafficking and release process.

Development and Evaluation of Particulate Microcarriers of Adapalene as a Topical Delivery System

2019 ◽  
Vol 9 (3) ◽  
pp. 222-233
Author(s):  
Divya D. Jain ◽  
Namita D. Desai
Keyword(s):  
Patient Compliance ◽  
Targeted Delivery ◽  
Ex Vivo ◽  
Acne Vulgaris ◽  
Drug Loading ◽  
Topical Therapy ◽  
Skin Irritation ◽  
Topical Delivery ◽  
Diffusion Method ◽  
Topical Gel

Background: Adapalene is a promising third generation retinoid used in the topical treatment of acne vulgaris. However, the major drawback associated with conventional topical therapy of Adapalene is the ‘retinoid reaction’ which is dose-dependent and characterized by erythema, scaling and burning sensation at the application sites. Microparticulate drug delivery can play a major role in reducing side effects and providing better patient compliance due to targeted delivery. Methods: Adapalene microparticles were prepared using quasi emulsion solvent diffusion method. The effects of formulation variables including polymer ratios, amounts of emulsifier, drug loading and process variables such as stirring time and speed on the physical characteristics of microparticles were investigated. The developed microparticles were characterized by DSC and SEM. Adapalene microparticles were incorporated into Carbopol 971 NF gel for ease of topical delivery. Results: Adapalene microparticulate topical gel showed sustained drug release over 8 hours in in vitro studies. The amount of drug retained in the rat skin during ex vivo studies was higher in the microparticulate topical gel (227.43 ± 0.83 µg/cm2) as compared to the marketed formulation (81.4 ± 1.11 µg/cm2) after 8 hours indicating localized and sustained drug action that can be useful in treating acne vulgaris. The safety of optimized Adapalene gel determined by skin irritation studies performed on Sprague Dawley rats showed no irritation potential. Conclusion: Microparticles can provide promising carrier systems to deliver Adapalene, improving patient compliance due to enhanced skin deposition, localized and sustained action with reduced associated irritant effects.

Electroanalytical chemistry of vanadium complexes: Electrochemical oxidation of [V(IV)O(nta)(H2O)]-

1989 ◽  
Vol 54 (1) ◽  
pp. 64-69 ◽  
Author(s):  
Roland Meier ◽  
Gerhard Werner ◽  
Matthias Otto
Keyword(s):  
Cyclic Voltammetry ◽  
Electrochemical Oxidation ◽  
Ph Dependence ◽  
Differential Pulse ◽  
Nitrilotriacetic Acid ◽  
Reduced Form ◽  
Vanadium Complexes ◽  
Differential Pulse Polarography ◽  
Electroanalytical Chemistry ◽  
Ph Range

Electrochemical oxidation of [V(IV)O(nta)(H2O)]- (H3nta nitrilotriacetic acid) was studied in aqueous solution by means of cyclic voltammetry, differential pulse polarography, and current sampled DC polarography on mercury as electrode material. In the pH-range under study (5.5-9.0) the corresponding V(V) complex is produced by one-electron oxidation of the parent V(IV) species. The oxidation product is stable within the time scale of cyclic voltammetry. The evaluation of the pH-dependence of the half-wave potentials leads to a pKa value for [V(IV)O(nta)(H2O)]- which is in a good agreement with previous determinations. The measured value for E1/2 is very close to the formal potential E0 calculated via the Nernst equation on the basis of known literature values for log Kox and log Kred, the complex stability constants for the oxidized and reduced form, respectively.

Efficient Preconcentration of Cu2+, Zn2+ and Fe3+ with an Agarose-Schiff Base Sorbent

2007 ◽  
Vol 72 (7) ◽  
pp. 908-916 ◽  
Author(s):  
Payman Hashemi ◽  
Hatam Hassanvand ◽  
Hossain Naeimi
Keyword(s):  
Schiff Base ◽  
Metal Ions ◽  
Metal Ion ◽  
Good Accuracy ◽  
Kinetic Studies ◽  
Sample Volume ◽  
Effects Of Ph ◽  
Glass Column ◽  
High Concentrations ◽  
Ph Range

Sorption and preconcentration of Cu2+, Zn2+ and Fe3+ on a salen-type Schiff base, 2,2'- [ethane-1,2-diylbis(nitrilomethylidyne)]bis(2-methylphenol), chemically immobilized on a highly crosslinked agarose support, were studied. Kinetic studies showed higher sorption rates of Cu2+ and Fe3+ in comparison with Zn2+. Half-times (t1/2) of 31, 106 and 58 s were obtained for sorption of Cu2+, Zn2+ and Fe3+ by the sorbent, respectively. Effects of pH, eluent concentration and volume, ionic strength, buffer concentration, sample volume and interferences on the recovery of the metal ions were investigated. A 5-ml portion of 0.4 M HCl solution was sufficient for quantitative elution of the metal ions from 0.5 ml of the sorbent packed in a 6.5 mm i.d. glass column. Quantitative recoveries were obtained in a pH range 5.5-6.5 for all the analytes. The volumes to be concentrated exceeding 500 ml, ionic strengths as high as 0.5 mol l-1, and acetate buffer concentrations up to 0.3 mol l-1 for Zn2+ and 0.4 mol l-1 for Cu2+ and Fe3+ did not have any significant effect on the recoveries. The system tolerated relatively high concentrations of diverse ions. Preconcentration factors up to 100 and detection limits of 0.31, 0.16 and 1.73 μg l-1 were obtained for Cu2+, Zn2+ and Fe3+, respectively, for their determination by a flame AAS instrument. The method was successfully applied to the metal ion determinations in several river water samples with good accuracy.

Red-fluorescent graphene quantum dots from guava leaf as a turn-off probe for sensing aqueous Hg(ii)

2021 ◽  
Vol 45 (10) ◽  
pp. 4617-4625
Author(s):  
Rahul V. Khose ◽  
Goutam Chakraborty ◽  
Mahesh P. Bondarde ◽  
Pravin H. Wadekar ◽  
Alok K. Ray ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Metal Ion ◽  
Leaf Extract ◽  
Graphene Quantum Dots ◽  
Toxic Metal ◽  
Guava Leaf

In this work, we have prepared red-fluorescent graphene quantum dots and utilized as a highly selective and sensitive fluorescence turn-off probe for detection of the toxic metal ion Hg2+ from guava leaf extract.

Sign in / Sign up

Export Citation Format

Share Document