Acetaminophen

A study on antioxidant and hepatoprotective activity of hydroalcoholic extract of Hylocereus undatus fruits against acetaminophen and ethanol induced hepatotoxicity was conducted in experimental rats. Two doses 250mg/kg and 500mg/kg, p.o. of the extract were subjected for the evaluation of hepatoprotective potential against acetaminophen (2g/kg) and ethanol (2ml/100g) induced liver injury. Silymarin (25mg/kg) was used as a standard drug. The parameters like SGPT, SGOT, ALP, total bilirubin, direct bilirubin and endogenous enzymes were estimated to assess the liver functions. Both the lower (250mg/kg) and higher dose (500mg/kg) of Hylocereus undatus fruit extract showed dose dependent significant decrease in SGPT, SGOT, ALP, total bilirubin and direct bilirubin levels when compared with toxic control. Both the doses showed decrease in LPO and increase in GSH levels. The present study concluded that Hylocereus undatus fruit was found to be effective against hepatotoxicity induced by acetaminophen and ethanol. Further studies are needed to isolate and characterize the active principles and to find out the mechanism responsible for its hepatoprotective activity.

The analysis of improved HPLC-UV detector method for the separation and quantification of Acetaminophen, Dextromethorphan hydrobromide and Doxylamine succinate is described. Samples are analysed by means of reverse phase (RP-HPLC) using a Zodiac C-18, (250 × 4.6 mm, 5 µ), and the mobile phase consists of two Channels A and B. Channel-A pH 6.0 Buffer: Methanol (85:15) and Channel-B pH 3.0 Buffer: Acetonitrile (70:30). The flow rate is 1.0 ml/min. The column temperature was maintained at 30˚C and sample temperature was maintained at ambient and wavelength fixed at 245nm UV-detection. It is found that the method of RP-HPLC with UV-detection system for the analysis of Acetaminophen, Dextromethorphan hydrobromide and Doxylamine succinate is straight forward and applied in qualitative and quantitative analysis. The developed LC method was validated with respect to specificity, precision, linearity, ruggedness, stability of analytical solution and robustness. Validation study compared as per ICH guideline.

A simple, precise, and rapid high performance liquid chromatography (HPLC) method for the determination of acetaminophen level in human plasma using caffeine as an internal standard (IS) was developed and validated. 0.5 ml plasma samples containing acetaminophen were mixed with 50 µg of the IS. After adding 30 µl of 50% perchloric acid, the mixture was vortexed for one minute and then centrifuged for 5 minutes at 13200 rpm. The clear supernatant was transferred into an auto-sampler vial and 100 µl was injected into the HPLC system with a run time of 7.0 min. The compounds of interest were efficiently separated on Symmetry C18 (4.6 x 150 mm, 5-µm) column, and were detected with a photodiode array detector set at 245 nm. The mobile phase consisted of water, methanol, and acetonitrile (80:10:10, v:v:v) and was delivered at a flow rate of 0.9 ml/min. No interference in blank plasma or by commonly used drugs was observed; and the detection limit of acetaminophen was 0.05 µg/ml. The relationship between acetaminophen concentration in plasma and peak area ratio of acetaminophen /IS was linear (r2 ≥ 0.9991) in the range of 0.1– 40 µg/ml. Intra- and inter-day coefficient of variations (CV) and biases were ≤11.6%  and  ≤10.8%, and ≤≤14.0 and ≤12.8, respectively. Extraction recovery of acetaminophen and the IS from the plasma samples was ≥99% and 86%, respectively. Using the method, acetaminophen was found to be stable under conditions generally encountered in the clinical laboratory (≥99% and 91% in processed and unprocessed samples, respectively). Further, the method was successfully used to measure acetaminophen level in plasma samples from a healthy volunteer.

A simple, precise, accurate, simultaneous and stability-indicating HPLC method developed with an effective resolution of active pharmaceutical ingredients. The present method effectively separates all the related substances of Diphenhydramine hydrochloride and acetaminophen along with impurities. Chromatographic separation has been obtained on Inertsil C18 (250 X 4.6mm, 5µ) column using a gradient elution with a mixture of phosphate buffer pH3.0 and acetonitrile. At 220 nm compounds will be eluted and monitored. Diphenhydramine hydrochloride and acetaminophen were subjected to the stress conditions of acid, base, peroxide, thermal, photolytic, humidity and water degradation. The degradation products were well resolved from main peak and its impurities, proving the stability-indicating ability of the method. The developed method was validated as per International Conference on Harmonization (ICH) guidelines and validation acceptance criteria were met in all cases. The current method has proven good linearity and accuracy over the range of all known impurities from LOQ to 150% of the target concentration. The degree of reproducibility, as results obtained by deliberate changes in the method parameter and variety of condition has proven that the method is robust and rugged.

A sensitive and selective RP-HPLC method is described for the determination of stability in Acetaminophen and Tramadol dosage forms. Chromatographic separation was achieved on a C18 column using mobile phase consisting of a mixture of mixed Phosphate buffer pH: 3.4 Acetonitrile (30:70v/v/v), with detection of 236nm and flow rate at 1mL/min. Linearity was observed in the range 100-300 µg /ml for Acetaminophen (r2 =0.994) & 10-30µg /ml for Tramadol (r2 =0.994) for the amount of drugs estimated by the proposed methods was in good agreement with the label claim. No chromatographic interference from tablet excipients was found. The proposed methods were validated. The force degradation of the drugs was assessed by different environmental conditions. Recovery experiments indicated the absence of interference from commonly encountered pharmaceutical additives. The method was found to be precise as indicated by the repeatability analysis, showing %RSD less than 2. All statistical data proves validity of the methods and can be used for routine analysis of pharmaceutical dosage form.

A simple, reliable, rapid, precise, sensitive and validated RP-HPLC method has been developed to determine Acetaminophen (AI) and Prasugrel (PRA) in synthetic mixture form. Chromatographic separation achieved isocratically on Luna C18 column (5 µm, 150mm x 4.60mm) and acetonitrile: 0.05M ammonium acetate buffer (pH 4.5) in the ratio of 75:25 (v/v) as the mobile phase, at a flow rate of 0.6 mL/min. Detection was carried out at 245 nm. Parameters such as linearity, precision, accuracy, recovery, specificity and ruggedness are studied as reported in the ICH guidelines. The retention times for AI and PRA was found to be 2.25 ± 0.5 and 8.72 ± 0.5 min respectively. Linearity for AI and PRA was in the range of 75-375 μg/mL and 10-50 μg/mL respectively.  The mean recoveries obtained for AI and PRA were 99.58 and 99.48% respectively and RSD was less than 2. The correlation coefficients for all components are close to 1. Developed method was found to be accurate, precise, selective and rapid for simultaneous estimation of AI and PRA.