scholarly journals Analysis of Dissolution of Salicylamide from Carrageenan Based Hard-Shell Capsules: A Study of the Drug-Matrix Interaction

2020 ◽  
Vol 21 (1) ◽  
pp. 148
Author(s):  
Muhammad Al Rizqi Dharma Fauzi ◽  
Esti Hendradi ◽  
Pratiwi Pudjiastuti ◽  
Riyanto Teguh Widodo

In drug release kinetics, the drug-matrix interaction is one of the important mechanisms to be dictated. Unfortunately, there is still minimum information discussing the effect of interaction between a drug and its matrix to the release profile of the drug. Therefore, there is an urgent need to conduct research related to the study of drug-matrix interaction. This paper reports the preparation of a drug delivery system (DDS) in the form of hard-shell capsules containing salicylamide (SCA) and analyses its drug-matrix interaction via dissolution test at different pH media and various release kinetics models. The matrix of hard-shell capsules was prepared from κ-carrageenan (CRG), crosslinked with maltodextrin (MD), and plasticized by sorbitol (SOR). The chemical properties of SCA were compared with paracetamol (PCT) using computational analysis to help to depict its drug-matrix interaction. The statistical analyses showed that SCA and PCT at pH 1.2, 4.5, and 6.8 had all different release profiles. Based on the goodness of fit evaluation, the diffusion mechanism of SCA at pH 1.2 and 4.5 could be best described by the Peppas-Sahlin model while the zeroth-order model fitted the dissolution profile at pH 6.8. In summary, it was proven that a different drug-matrix interaction produced a different dissolution profile.

Author(s):  
Pratik Swarup Das ◽  
Puja Saha

Objective: In present work was designed to develop suitable transdermal matrix patches of Phenformin hydrochloride using various hydrophilic (HPMC) and hydrophobic (EUDRAGID) polymers as matrix formers.Methods: Transdermal patches containing Phenformin hydrochloride were prepared by the solvent casting evaporation technique.Results: Revealed that prepared patches showed good physical characteristics, no drug-polymer interaction and no skin irritation was observed. The in vitro release study revealed that F3 formulation showed maximum release in 24 h. Formulation F3 was subjected for accelerated stability studies. The F3 formulation was found to be stable as there was no drastic change in the Physico-chemical properties of the patches, which was also confirmed by FTIR.Conclusion: Thus conclusion can be made that stable transdermal patches of Phenformin hydrochloride has been developed. F1, F2, F3, F4 formulations showed highest cumulative percentage drug release of 98.13%, 95.50%, 98.65%, 97.21% were obtained during in vitro drug release studies after 24 h. The release of Phenformin hydrochloride appears to be dependent on lipophilicity of the matrix. Moderately lipophillic matrices showed best release. The predominant release mechanism of drug through the fabricated matrices was believed to be by diffusion mechanism. Based upon the in vitro dissolution data the F3 formulation was concluded as optimized formulation.


2020 ◽  
Vol 18 (1) ◽  
pp. 226-231
Author(s):  
Pratiwi Pudjiastuti ◽  
Siti Wafiroh ◽  
Esti Hendradi ◽  
Handoko Darmokoesoemo ◽  
Muji Harsini ◽  
...  

AbstractThe release of drugs from solid drug delivery materials has been studied intently in recent years. Quantitative analyses achieved from in vitro dissolution becomes easier if a zero-order mathematical model is used. Non-gelatin nutraceutical hard-shell capsules of zero size (approximately 0.7-0.8 cm) were produced from carrageenan-based natural polymers, namely carrageenan-alginate (CA) and carrageenan-starch (CS). Disintegration, dissolution and zero-order drug release kinetics of hard-shell capsules containing 100 mg of salicylamide were studied. The disintegration time of CA and CS were observed to be less than 30 min for both CA and CS. In vitro dissolution profile showed that the percentage dissolution of CA capsules was better at pH 4.5, while that of CS was poor at pH 1.2, 4.5 and 6.8. Determination of drug release kinetics profiles of carrageenan-based hardshell capsules utilized the Noyes-Whitney and Peppas-Sahlin modification rules for zero-order. The drug release from carrageenan-based capsules followed zero-order kinetics, especially at pH 6.8, and was compared to the Higuchi model. Salicylamide in CA hard-shell capsules at a pH 6.8 had a release rate constant (kH) of 2.91 %(ppm/ ppm) min-1/2, while the release rate constant of CS was 0.36 %(ppm/ppm) min-1.


2021 ◽  
Vol 18 (1) ◽  
pp. 7-14
Author(s):  
Dian Eka Ermawati ◽  
Anif Nur Artanti ◽  
Dyah Ayu Ambarwati ◽  
Niken Rosyana Dewi Septini ◽  
Sholichah Rohmani ◽  
...  

The liquid extract of antihypertensive herbs could reduce blood pressure equivalent to Hydrochlorothiazide 25 mg based on research conducted in “Hortus Medicus” clinic, Tawangmangu, Central Java, but parameters of herbal medicine taste, design, and packaging had the lowest scores. Transdermal patch was chosen as an alternative to resolve those problems. Polymers determined the effectiveness of the active substance release from the formula. Patch was formulated from combination of hydrophilic hydroxy methylcellulose (HPMC) and carboxymethylcellulose natrium (CMC-Na) polymer which would produce a fast release profile. The objective of this research was to study the kinetics models of total flavonoid release and to study the total number of flavonoids released from the antihypertensive herbs patch for 5 hours, as well as to determine the optimum formula for observing the weight, pH and loss on drying. Herbs were infused with distilled water at 90 ° C for 15 minutes, filtered then evaporated. Release kinetics model used a modified type-5 dissolution apparatus equipment with a cellophane membrane. The optimum proportion of HPMC and CMC-Na was 220:180 mg. Patch was dark brown, circle shaped, moist and flexible. It had pH value of 7.29 ± 0.09, folding endurance of >350, and thickness of 0.64 ± 0.05 mm. The average percentage of total flavonoids released from the matrix patch was 37.23% for 5 hours. The release kinetics followed the Higuchi kinetics model with a diffusion mechanism.


Author(s):  
N. Y. Jin

Localised plastic deformation in Persistent Slip Bands(PSBs) is a characteristic feature of fatigue in many materials. The dislocation structure in the PSBs contains regularly spaced dislocation dipole walls occupying a volume fraction of around 10%. The remainder of the specimen, the inactive "matrix", contains dislocation veins at a volume fraction of 50% or more. Walls and veins are both separated by regions in which the dislocation density is lower by some orders of magnitude. Since the PSBs offer favorable sites for the initiation of fatigue cracks, the formation of the PSB wall structure is of great interest. Winter has proposed that PSBs form as the result of a transformation of the matrix structure to a regular wall structure, and that the instability occurs among the broad dipoles near the center of a vein rather than in the hard shell surounding the vein as argued by Kulmann-Wilsdorf.


Author(s):  
O. Popoola ◽  
A.H. Heuer ◽  
P. Pirouz

The addition of fibres or particles (TiB2, SiC etc.) into TiAl intermetallic alloys could increase their toughness without compromising their good high temperature mechanical and chemical properties. This paper briefly discribes the microstructure developed by a TiAl/TiB2 composite material fabricated with the XD™ process and forged at 960°C.The specimens for transmission electron microscopy (TEM) were prepared in the usual way (i.e. diamond polishing and argon ion beam thinning) and examined on a JEOL 4000EX for microstucture and on a Philips 400T equipped with a SiLi detector for microanalyses.The matrix was predominantly γ (TiAl with L10 structure) and α2(TisAl with DO 19 structure) phases with various morphologies shown in figure 1.


2011 ◽  
Vol 47 (3) ◽  
pp. 545-553 ◽  
Author(s):  
Sathis Kumar Dinakaran ◽  
Santhos Kumar ◽  
David Banji ◽  
Harani Avasarala ◽  
Venkateshwar Rao

The purpose of this research study was to establish ziprasidone HCl NR 40 mg and trihexyphenidyl HCl SR 4mg in the form of bi-layer sustained release floating tablets. The tablets were prepared using sodium HPMC K4M / HPMC K15M as bio-adhesive polymers and sodium bicarbonate acting as a floating layer. Tablets were evaluated based on different parameters such as thickness, hardness, friability, weight variation, in vitro dissolution studies, content of active ingredient and IR studies. The physico-chemical properties of the finished product complied with the specifications. In vitro release from the formulation was studied as per the USP XXIII dissolution procedure. The formulations gave a normal release effect followed by sustained release for 12 h which indicates bimodal release of ziprasidone HCl from the matrix tablets. The data obtained was fitted to Peppas models. Analysis of n values of the Korsmeyer equation indicated that the drug release involved non-diffusional mechanisms. By the present study, it can be concluded that bi-layer tablets of ziprasidone HCl and trihexyphenidyl HCl will be a useful strategy for extending the metabolism and improving the bioavailability of Ziprasidone HCl and Trihexyphenidyl HCl.


2012 ◽  
Vol 610-613 ◽  
pp. 762-765
Author(s):  
Fu Chen ◽  
Shu Shen Liu

Assessments of the relative risks posed by chemicals are needed to assist in the development of management plans that minimize ecological impacts. A procedure scoring and screening chemicals entitled ranking procedure based on risk percentile index and concentration (rrpic) was developed based on inherent physico-chemical properties and toxicity as well as detection concentration. The properties and toxicity were transformed into risk percentile indices (rpi) and the rpi was then used to calculate risk score (rs) by multiplying the detection concentration. Using Hasse diagram, the chemicals having different rss were classified into several rank levels. The averaged rank (rav) of each chemical was calculated by using Local Partial Order Model (LPOM) and the risks of chemicals were arranged in a linear order. The rrpic was employed to scoring and screening 31 chemicals detected in Taihu Lake of China.


Author(s):  
Rushil Pingali ◽  
Sourabh K. Saha

Abstract Two-photon lithography (TPL) is a polymerization-based direct laser writing process that is capable of fabricating arbitrarily complex three-dimensional (3D) structures with submicron features. Traditional TPL techniques have limited scalability due to the slow point-by-point serial writing scheme. The femtosecond projection TPL (FP-TPL) technique increases printing rate by a thousand times by enabling layer-by-layer parallelization. However, parallelization alters the time and the length scales of the underlying polymerization process. It is therefore challenging to apply the models of serial TPL to accurately predict process outcome during FP-TPL. To solve this problem, we have generated a finite element model of the polymerization process on the time and length scales relevant to FP-TPL. The model is based on the reaction-diffusion mechanism that underlies polymerization. We have applied this model to predict the geometry of nanowires printed under a variety of conditions and compared these predictions against empirical data. Our model accurately predicts the nanowire widths. However, accuracy of aspect ratio prediction is hindered by uncertain values of the chemical properties of the photopolymer. Nevertheless, our results demonstrate that the reaction-diffusion model can accurately capture the effect of controllable parameters on FP-TPL process outcome and can therefore be used for process control and optimization.


1970 ◽  
Vol 8 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Mohammad Nezab Uddin ◽  
Ishtiaq Ahmed ◽  
Monzurul Amin Roni ◽  
Muhammad Rashedul Islam ◽  
Mohammad Habibur Rahman ◽  
...  

The objective of this study was to design oral sustained release matrix tablets of Ranolazine usinghydroxypropyl methylcellulose (HPMC) as the retardant polymer and to study the effect of formulation factors suchas polymer proportion and polymer viscosity on the release of drug. In vitro release studies were performed usingUSP type II apparatus (paddle method) in 900 mL of 0.1N HCl at 100 rpm for 12 hours. The release kinetics wasanalyzed using the zero-order, first order, Higuchi and Korsmeyer-Peppas equations to explore and explain themechanism of drug release from the matrix tablets. In vitro release studies revealed that the release rate decreasedwith increase in polymer proportion and viscosity grade. Mathematical analysis of the release kinetics indicated thatthe nature of drug release from the matrix tablets was dependent on drug diffusion and polymer relaxation andtherefore followed non-Fickian or anomalous release. The developed controlled release matrix tablets of Ranolazineprepared with high viscosity HPMC extended release up to 12 hours.Key words: Ranolazine; Sustained release; Methocel E50 Premium LV; Methocel K100LV CR; Methocel K4M CR;Methocel K15M CR.DOI: 10.3329/dujps.v8i1.5333Dhaka Univ. J. Pharm. Sci. 8(1): 31-38, 2009 (June)


2006 ◽  
Vol 514-516 ◽  
pp. 1116-1120 ◽  
Author(s):  
M.Fátima Cerqueira ◽  
Margarita Stepikhova ◽  
Maria Losurdo ◽  
Teresa Monteiro ◽  
Manuel J. Soares ◽  
...  

Erbium doped nanocrystalline silicon thin films were produced by reactive magnetron r.f. sputtering. Their structural and chemical properties were studied by micro-Raman, spectroscopic ellipsometry and Rutherford backscattering spectroscopy. Films with different crystalline fraction and crystallite size were deposited by changing the deposition parameters. The impact of the composition and structure of Erbium ions environment on the 1.5 µm photoluminescence is discussed.


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