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Densitometric HPTLC analysis of cordifolioside A in Tinospora cordifolia and commercial formulations

100%

Alam P. , Ali M. , Singh R. , Shakeel F.

Acta Chromatographica

2009

tom Vol. 21, no. 4

683--692

A densitometric HPTLC method for analysis of cordifolioside A both in 60% methanolic extract of Tinospora cordifolia and in a commercial formulation has been established and validated. Cordifolioside A was separated on aluminum-backed silica gel 60 F254 plates with chloroform-methanol 85:15 (%, v/v ) as mobile phase. A compact band was obtained for cordifolioside A at R F 0.52 ± 0.03. The limits of detection (LOD) and quantification (LOQ) were 20.12 and 60.36 ng per band, respectively. The highly precise and accurate method was used for analysis of cordifolioside A.

A new TLC densitometric method for stability assessment of modafinil

75%

Faisal M. S. , Naz Z. , Shakeel F. , Ahmed S. , Kohli K. , Khar R. K.

Chemia Analityczna

2009

tom Vol. 54, No. 1

77-88

TLC densitometric method for simple and sensitive stability assessment of modafinil has -been developed. The objective was to provide a rapid, precise, robust, and reproducible technique for the analysis of modafinil. The method was validated for bulk drug and tablet , formulations. It could be used to separate the drug from its degradation products. The pro- cedure employed TLC aluminum plates precoated with 60F-254 silica gel as the stationary phase. The solvent system consisted of toluene-chloroform-methanol (1:1:0.5, v/v/v) 'o'o mixture. It provided well-resolved compact spots for modafinil (Rr value 0.46 š 0.01) and allowed for separation of the excipients and degradation products. Densitometric scanning interegation was performed at the wavelength of 220 nm. Calibration plot was linear , (r2 = 0.999) in the analyte concentration range 100-5000 ng per spot. The method was validated with respect to linearity, accuracy recovery, precision, ruggedness, and specificity. The limit of detection and quantification were 20.54 ng per spot and 62.26 ng per spot, respectively. The determined drug content was within the š5% range of the labeled content. The drug was analyzed under different stress conditions in order to study its degradation in the presence of acid, base, and peroxide.

Opracowano densytometryczną metodę TLC pozwalającą na proste i czułe badanie stabilności modafinilu. Opracowana technika była szybka, precyzyjna, odporna na warunki zewnętrzne i powtarzalna. Metodę zwalidowano dla substancji farmaceutycznej i tabletek. Można ją stosować do oddzielenia leku od produktów rozkładu. Jako fazę stacjonarną użyto żel krzemionkowy 60F-254 naniesiony na płytki aluminiowe. Fazę ruchomą stanowiła '"' mieszanina: toluen-chlorofbrm-metanol (1:1:0,5; v/v/v). Otrzymywano dobrze rozdzielone, zwarte plamki modafinilu (wartość Rf 0.46 š 0.01), oddzielone od substancji pomocniczych i produktów rozkładu. Skanowanie densytometryczne prowadzono przy długości fali 220 nm. Krzywa kalibracyjna miała charakter liniowy (r2 = 0,999) w zakresie stężeń analitu 100-5000 ng na plamkę. Metodę zwalidowano w zakresie liniowości, dokładności, odzysku, precyzji, odporności na czynniki zewnętrzne i specyficzności. Granica wykrywalności i oznaczalności ilościowej wynosiły odpowiednio 20,54 ng i 62.26 ng na plamkę. Oznaczana zawartość leku mieściła się w granicach š 5% ilości deklarowanej. Lek analizowano w różnych warunkach stresowych w celu zbadania jego degradacji w obecności kwasów, zasad i nadtlenków.

Silymarin: an insight to its formulation and analytical prospects

75%

Ahmad U. , Faiyazuddin M. , Hussain M. T. , Ahmad S. , Alshammari T. M. , Shakeel F.

Acta Physiologiae Plantarum

2015

tom 37

nr 11

Silymarin, a potential phytochemical compound obtained from the seeds of Silybum marianum plant has been used as a hepatoprotective agent for more than a decade. So far, eight active components of silymarin flavonolignans have been identified, among which silibinin has been proven the most active. However, it had poor oral bioavailability due to extensive phase II metabolism, low permeability across intestinal epithelial cells, low aqueous solubility, and rapid excretion in bile and urine. Therefore it becomes necessary to understand all its formulation and analytical aspects from past to present, including all of its possible future prospects. In modern research scenario, nanotization strategies of drugs has served as a potential approach to enhance solubility, bioavailability and to develop a robust formulation. Several approaches have been utilized previously to enhance the solubility and bioavailability of silymarin to provide it a robust strength against physical, chemical, and environmental degradation. Nanoscale formulations such as nanoemulsion, nanosuspension, liposomes, and solid–lipid nanoparticles can be used to enhance solubility and to target them to desired cells with minimum harm to normal cells. However, many other approaches exist such as dendrimers, ceramic nanoparticles, and carbon nanotubes, which serve as a great vehicle in drug delivery to transport medicament at target sites. Therefore, the purpose of this review was to develop a better understanding of the problems associated with silymarin and approaches to overcome the difficulties to develop a better and stable formulation for food and pharmaceutical applications.