UTILIZATION OF SAMANYA SHODHANA IN THE PURIFICATION OF EXCESS MERCURY OBTAINED FROM DENTAL OPERATORY- A PRELIMINARY STUDY

Background: Concerns about toxicity of mercury and disposal of excessive mercury has led to decreased usage of mercury in dental profession but still tooth colored restorative materials are not affordable by all the classes of any society. The disposal of excess mercury has always been a matter of concern. Thus, in the present study, we attempted to evaluate a simple procedure from Rasa Shastra using lime powder, garlic and rock salt for recycling of excess mercury obtained from dental operatory.Materials and methods: The excess mercury was recycled by the standard procedure explained in Ayurveda texts (Samanya shodhana) using Sudha churna (lime powder), Lashuna kalka (paste of Allium sativum L.) and Saindhava lavanaa (rock salt). The commercially available mercury and recycled mercury was analyzed by inductively coupled plasma mass spectrometry (ICP-MS) for the detection of elements in ppm level.Results: It was found that the excess impure mercury contained 5138 ppm, 2866.1 ppm and 0.371 ppm of Silver, Copper and Tin respectively. After Shodhana, the level of silver, tin and copper were markedly reduced. Purified mercury showed a level of 119.5ppm silver, 0.5324 ppm copper and 0.3233 ppm tin.Conclusion: Samanya shodhana is a simple promising procedure which can be used for mercury recycling. The procedure doesnot require sophisticated equipments and maneuver. Further, the materials used in the procedure are easily available and affordable at low cost

Hydrophobicity effects in iron polypyridyl complex electrocatalysis within Nafion thin-film electrodes

Four polypyridyl redox catalysts Fe(bp)32+, Fe(ph)32+, Fe(dm)32+, and Fe(tm)32+ (with bp, ph, dm, and tm representing 2,2′-bipyridine, 1,10-phenanthroline, 4,4′-dimethyl-2,2′-bipyridine, and 3,4,7,8-tetramethyl-1,10-phenanthroline, respectively) are investigated for the electrocatalytic oxidation of three analytes (nitrite, arsenite, and isoniazid).</p

DEVELOPMENT AND VALIDATION OF LIQUID CHROMATOGRAPHY AND SPECTROSCOPIC METHODS FOR THE ANALYSIS OF DOXOFYLLINE IN PHARMACEUTICAL DOSAGE FORMS

A high performance liquid chromatography (HPLC) and ultraviolet spectroscopic (UV) methods were developed and validated for the quantitative estimation of doxofylline (DF) in pharmaceutical dosage forms. HPLC was carried out using reversephase technique on RP-8 column with a mobile phase composed of 0.05M phosphate buffer pH 6 and acetonitrile (60:40, v/v). The mobile phase was pumped at a flow rate of 1mL/min, and detection was made at 230nm with PDA detector. UV method was performed with λ max at 270nm with apparent molar absorptive of 0.878x103 L mol-1 cm-1. Both the methods showed good linearity, recovery and precision. No spectral or chromatographic interferences from the tablet excipients were found in UV and HPLC methods. The various parameters such as linearity, precision, accuracy, specificity, and robustness, limit of detection and limit of quantization were studied according to ICH guidelines. Statistical analysis was done by student’s t-test and F-test, which showed no significant difference between the results of both methods. So the proposed methods could be applicable for routine analysis of DF and monitoring of the quality of marketed drugs

DEVELOPMENT AND VALIDATION OF LIQUID CHROMATOGRAPHY AND SPECTROSCOPIC METHODS FOR THE ANALYSIS OF DOXOFYLLINE IN PHARMACEUTICAL DOSAGE FORMS

A high performance liquid chromatography (HPLC) and ultraviolet spectroscopic (UV) methods were developed and validated for the quantitative estimation of doxofylline (DF) in pharmaceutical dosage forms. HPLC was carried out using reversephase technique on RP-8 column with a mobile phase composed of 0.05M phosphate buffer pH 6 and acetonitrile (60:40, v/v). The mobile phase was pumped at a flow rate of 1mL/min, and detection was made at 230nm with PDA detector. UV method was performed with λ max at 270nm with apparent molar absorptive of 0.878x103 L mol-1 cm-1. Both the methods showed good linearity, recovery and precision. No spectral or chromatographic interferences from the tablet excipients were found in UV and HPLC methods. The various parameters such as linearity, precision, accuracy, specificity, and robustness, limit of detection and limit of quantization were studied according to ICH guidelines. Statistical analysis was done by student’s t-test and F-test, which showed no ignificant difference between the results of both methods. So the proposed methods could be applicable for routine analysis of DF and monitoring of the quality of marketed drugs. Key words: Doxofylline, Validation, HPLC, UV spectroscopy, Comparisonstudies, Student’s t-test, F-test

Electrocatalytic Oxidation and Determination of Cysteine at Oxovanadium(IV) Salen Coated Electrodes

A transition metal complex, oxovanadium(IV) salen (where salen represents N,N -bis(salicylidene)ethylenediamine) is immobilized on glassy carbon (GC) electrodes and utilized for electrocatalytic oxidation of cysteine. In presence of oxovanadium(IV) salen, increased oxidation current is observed due to the effective oxidation of cysteine by the electrogenerated oxovanadium(V) salen species. The oxidation current linearly varies with the concentration of cysteine from 0.1 to 1.0 mM. The modified electrode has good sensitivity and low limit of detection. These properties make the oxovanadium(IV) salen as an effective electrocatalyst for the determination of cysteine

Electrocatalytic Oxidation and Determination of Cysteine at Oxovanadium(IV) Salen Coated Electrodes

A transition metal complex, oxovanadium(IV) salen (where salen represents N,N′-bis(salicylidene)ethylenediamine) is immobilized on glassy carbon (GC) electrodes and utilized for electrocatalytic oxidation of cysteine. In presence of oxovanadium(IV) salen, increased oxidation current is observed due to the effective oxidation of cysteine by the electrogenerated oxovanadium(V) salen species. The oxidation current linearly varies with the concentration of cysteine from 0.1 to 1.0 mM. The modified electrode has good sensitivity and low limit of detection. These properties make the oxovanadium(IV) salen as an effective electrocatalyst for the determination of cysteine

CRYSTAL FORMS OF LOMEFLOXACIN: PREPARATION, CHARACTERIZATION AND DISSOLUTION PROFILE

The present work was undertaken with the synthesis of crystal forms of Lomefloxacin from solvents of varying polarity (polar, protic solvents). The purpose of the present investigation was to employ crystallization techniques in order to improve the solubility and dissolution studies of Lomefloxacin. The experimental methods involved the preparation of lomefloxacin crystals by crystallization from single solvent technique. Crystals were prepared from solvents like distilled water, ethanol and methanol. Prepared crystals were undergone various studies in terms of crystal yield, melting point, true density, solubility and in vitro drug release study as well as characterized by technique viz: FT-IR, differential scanning calorimetry (DSC) and Powder X-ray Diffractometry(PXRD). Photomicrographs of the crystals shows that the crystals obtained from different solvents existed in different shape. Among all the crystals, LOME-I belongs to Type-1 and LOME–II belongs to Type-2 based on instrumental techniques. Highest crystal yield (88%) and maximum density (1.2021g/mL) was observed with LOME-I. Maximum solubility and dissolution rate was observed in LOME-III followed by LOME-II and LOME-I. However all prepared crystal forms showed higher solubility and dissolution profile when compare with commercial Lomefloxacin. It is concluded that the study has indicated the existence of two polymorphic forms of Lomefloxacin which was having better solubility and in vitro release than that of commercial Lomefloxacin.Key words: Polymorphism, Solubility, Dissolution rate, DSC, FT-IR, PXR

CRYSTAL FORMS OF LOMEFLOXACIN: PREPARATION, CHARACTERIZATION AND DISSOLUTION PROFILE

The present work was undertaken with the synthesis of crystal forms of Lomefloxacin from solvents of varying polarity (polar, protic solvents). The purpose of the present investigation was to employ crystallization techniques in order to improve the solubility and dissolution studies of Lomefloxacin. The experimental methods involved the preparation of lomefloxacin crystals by crystallization from single solvent technique. Crystals were prepared from solvents like distilled water, ethanol and methanol. Prepared crystals were undergone various studies in terms of crystal yield, melting point, true density, solubility and in vitro drug release study as well as characterized by technique viz: FT-IR, differential scanning calorimetry (DSC) and Powder X-ray Diffractometry(PXRD). Photomicrographs of the crystals shows that the crystals obtained from different solvents existed in different shape. Among all the crystals, LOME-I belongs to Type-1 and LOME–II belongs to Type-2 based on instrumental techniques. Highest crystal yield (88%) and maximum density (1.2021g/mL) was observed with LOME-I. Maximum solubility and dissolution rate was observed in LOME-III followed by LOME-II and LOME-I. However all prepared crystal forms showed higher solubility and dissolution profile when compare with commercial Lomefloxacin. It is concluded that the study has indicated the existence of two polymorphic forms of Lomefloxacin which was having better solubility and in vitro release than that of commercial Lomefloxacin