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.
PL
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.
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Normothymic, antidepressant and antipsychotic pharmaceutics are, in accordance with international guidelines, employed both in the therapy and the prevention of bipolar disorder (BD). Long-term studies on the mechanisms of action of such medications, as well as on the pathogenetic background of BD, have led to the discovery of effective, albeit unconventional pharmacotherapeutic approaches. These methods have the potential to successfully treat mania and depression, as well as to counter affective episode relapse. Allopurinol - commonly used to treat gout, secondary hyperuricemia and Lesch-Nyhan syndrome, acts by inhibiting the synthesis of uric acid, levels of which are often increased in manic patients. Due to this, an evaluation of the potential effect of allopurinol on the reduction of mania symptoms seems to be reasonable. Additionally, the numerable research papers coming out of research regarding the role of purine neurotransmitters in mood alterations, indicate that adenosine agonists act analogously to dopamine antagonists. N-acetylcysteine (NAC), a supporting agent in the pharmacotherapy of depressive episodes in bipolar disorder, substantially accelerates mood stabilization in patients. In turn, memantine, known for its procognitive effect, not only has antimanic and normothymic properties, but also boosts the neuroprotective action of traditional lithium therapy. In view of the latest opinions, the subtle pro-inflammatory process is typical for the pathophysiology of bipolar disease. Acetylsalicylic acid (ASA) (a popular analgesic, antipyretic and antiphlogistic agent) may be useful in BD therapy. This is because that, via its effect upon cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2), ASA modulates leukocyte recruitment in neuro-inflammation. Apart from the above-mentioned medications, this article introduces the results of recent investigations of ketamine, modafinil and tamoxifen, including their receptor mechanisms, as well as certain genetic aspects or elements of their pharmacodynamics, for use in BD therapy. We put forward that, possibly, more insightful cognition of these drugs will allow significant enrichment in the range of pharmacotherapy for BD in the near future.
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