Mean Percentage Recoveries Research Articles

DEVELOPMENT OF METHOD AND VALIDATION FOR ASSAY IN IRINOTECAN HYDROCHLORIDE INJECTION BY APPLYING STABILITY INDICATING HPLC METHODOLOGY BY HPLC

A validated HPLC technique for determining Irinotecan Hydrochloride (IRN) in pharmaceutical formulations was developed. For this chromatographic investigation, isocratic elution at a flow rate of 1.0 ml/min was utilized on Zorbax C18 150mm 4.6 mm, 5μ, or similar. The mobile phase is made up of 45 volumes of methanol and 55 volumes of buffer solution. The UV detection wavelength was 220 nm, and a sample of 10.0 μl was injected. The run time for Sample, Unmarked, Placebo, System Suitability and Sensitivity solutions is approximately 12 minutes, and 60 minutes for diluted Regular. The approximate retention time for IRN was determined to be 3.8 minutes. The percentage R.S.D. IRN was determined. Irinotecan's mean percentage recovery is found to be within the specified limit. The approach was validated in accordance with ICH recommendations. As a result, the suggested HPLC approach may be successfully used for routine formulation quality control examination. The devised approach is simple and superior to the methods published in the literature.

Analytical profiling of Lentinan in hybrid nanostructures for intranasal Delivery: Method development and Validation

Lentinan (LNT) a polysaccharide obtained from mushroom Lentinus edodes, possesses potent anticancer and antitumor activity. To improve the bioavailability, encapsulation of LNT in polymer -lipid hybrid nanostructures (PLHNs) is done and administration via nasal pathway will bypass hepatic first-pass metabolism, which possibly will give high prospect for treatment of brain tumors. The estimation of entrapped LNT within Hybrid Nanostructures is one of the important parameters for the characterization of nanoparticles. Therefore, an analytical method was developed and validated for estimating plain LNT and LNT-PLHNs in Nasal Simulated Fluid (NSF) by conjugating with Congo Red (CR) in dilute alkaline solutions by employing high-performance liquid chromatography (HPLC). The developed method was validated for selectivity, linearity, precision, accuracy, robustness. The linearity was checked over the concertation range of 2–10 μg/mL the and limit of detection (LOD) and limit of quantification (LOQ) were 38.02 ± 0.21 ng/mL and 86.71 ± 0.82 ng/mL respectively. The mean percent recovery of LNT was 99.18 %; relative standard deviation (RSD) of 0.386 % and intra- and interday coefficient of variation was <2 %. The developed HPLC method was found suitable for assessing percent entrapment efficiency (%EE), in-vitro drug release, intracellular uptake study and stability profile of LNT-PLHNs obtained by solvent injection technique.

A simple and rapid RP-HPLC method for the assessment of cobalamin (vitamin B12) intilapia and snoek fishes

This study developed a rapid reversed-phase high-performance liquid chromatography (RP-HPLC) method equipped with a UV-Vis detector. The aquaponics system?s tilapia and marine snoek fishes were extracted using an autoclaving process and enzymatic treatment. The technique enabled the separation and quantification of cobalamin present in these fishes extracts. Phenomenex Luna® 5 μm C18 (2) 100 A LC-column (150 × 4.6 mm) was used as a stationary phase, while the mobile phase consisted of methanol and phosphoric acid in a ratio of 35:65 (v/v), respectively. The developed method was revealed to be rapid (a retention time of less than 5.0 min), linear (R2 = 0.9988), sensitive (limits of detection and quantification showed to be 0.0004 and 0.0011 μg/mL, respectively), precise (percentage relative standard deviation of 0.14% to 0.76%), and accurate (percentage mean recovery of 87.44 ± 0.33% to 97.08 ± 0.74%). The quantified concentrations of this vitamin in extracts of tilapia and snoek fishes were found to be 08.95 ± 0.35 and 14.97 ± 0.04 μg/ mL, respectively. Therefore, we suggested that the developed RP-HPLC technique could be applicable for quality control evaluation in the food and pharmaceutical industries. Besides, the method could be vital for diagnostic analysis in clinical laboratories.

Universal procedures for spectrophotometric determination of anticoccidial drugs; application to multi-ingredient veterinary formulation and computational investigations for multivariate analysis

Simple, accurate, and eco-friendly spectrophotometric procedures were proposed and implemented for simultaneous determination of anticoccidial drugs from three different classes namely, amprolium hydrochloride (AMP), sulfaquinoxaline sodium (SQX) and diaveridine hydrochloride (DVD). Dual wavelength in ratio spectra procedure was proposed where the difference in amplitudes (ΔP) in the ratio spectra at 264 nm and 301.9 nm (ΔP264&amp;301.9 nm) corresponded to AMP with mean percentage recovery 100.00±0.923%, while (ΔP250.9&amp;279 nm) and (ΔP218&amp;243.5 nm) corresponded to SQX and DVD with mean percentage recoveries 99.31±1.083 and 100.64±1.219%, respectively. The dual wavelength in ratio spectra procedure was validated according to the ICH guidelines and accuracy, precision and repeatability were found to be within the acceptable limit. Multivariate chemometric approaches, namely, partial least-squares (PLS-2) and principal component regression (PCR) were also proposed with mean percentage recoveries 99.31±0.769, 98.91±1.192 and 99.04±1.245% for AMP, SQX and DVD, respectively, in PLS-2 and 99.63±1.005, 99.11±1.272 and 98.93±1.338% for AMP, SQX and DVD, respectively, in PCR. These procedures were successfully applied to the multi-ingredient veterinary formulation with mean percentage recoveries 100.75±1.238, 99.29±0.875 and 99.34±0.745% for AMP, SQX and DVD, respectively, in dual wavelength in ratio spectra procedure and 101.03±1.261, 101.48±0.984 and 101.10±1.339% for AMP, SQX and DVD, respectively, in PLS-2 and 100.22±1.204, 101.10±0.546 and 100.91±0.677% for AMP, SQX and DVD, respectively, in PCR.

Spectrophotometric methods for determination of glimepiride and pioglitazone hydrochloride mixture and application in their pharmaceutical formulation

Simple, accurate, and precise four spectrophotometric methods were developed and validated for simultaneous determination of glimepiride and pioglitazone hydrochloride in their pharmaceutical formulation. The first spectrophotometric method was the dual-wavelength which determined glimepiride at 219.0 and 228.0 nm and pioglitazone hydrochloride at 268.0 nm. The second one is the first derivative of ratio spectra (DD1) spectrophotometry in which the peak amplitudes were used at 238.0 nm and 268.0 nm for glimepiride and pioglitazone hydrochloride, respectively. The third method is ratio subtraction in which glimepiride was determined at 228.0 nm in the presence of pioglitazone hydrochloride which was determined by extended ratio subtraction at 268.0 nm. The fourth method was the ratio difference to determine glimepiride and pioglitazone hydrochloride. Beer’s law was confirmed in the concentration range 2.50–15.00 µg mL-1, and 10.00–50.00 µg mL-1 for glimepiride and pioglitazone respectively for the four methods. The proposed methods were used to determine both drugs in their pure powdered form with mean percentage recoveries of 99.91 ± 1.117% for glimepiride and 99.76 ± 0.911% for pioglitazone hydrochloride in method (A). In method (B), the mean percentage recoveries were 100.12 ± 0.89% for glimepiride and 100.02 ± 1.06% for pioglitazone hydrochloride. In method (C) glimepiride was 100.01 ± 0.592% and 99.85 ± 0.845% for pioglitazone hydrochloride by extended ratio subtraction. And finally, in method (D) the mean percentage recoveries were 100.66 ± 0.670% for glimepiride and 99.92 ± 0.988% for pioglitazone hydrochloride. The developed methods were successfully applied for the determination of glimepiride and pioglitazone hydrochloride in pure powder and dosage form. The suggested methods were also used to determine both compounds in laboratory-prepared mixtures. The accuracy, precision, and linearity ranges of the developed methods were determined. The results obtained were compared statistically with the official method, and there was no significant difference between the proposed methods and the official method for accuracy and precision.

Versatile TLC-Densitometric Methods for the Synchronous Estimation of Cinnarizine and Acefylline Heptaminol in The Presence of Potential Impurity and Their Reported Degradation Products.

From evolution, thin-layer chromatography (TLC) attracts attention as a versatile technique for efficient separation and identification of many drug substances and chemicals. Owing to its simplicity and other outstanding advantages, TLC is extensively used by chromatographers in quantification and purity profiling objectives. In the present study two TLC-Densitometric methods are established and validated for the synchronous estimation of Cinnarizine (Cinn) and Acefyline Heptaminol (Acef) in the presence of Cinn/Acef reported degradation products and Thoephylline (Theo) as Acef potential impurity. The proposed methods are based on densitometric measurements of the spots of Cinn and Acef after separation from their degradation products. Separation is attained on silica gel sheet with dichloromethane: methanol: formic acid as a developing system in ratio: (15, 1, 0.5, by volume) and (15, 0.75, 0.4, by volume) for Cinn (method 1) and Acef (method 2) degradation, consecutively. Quantification is done at 254nm over concentration ranges of 0.2-1.8 and 2-18μg/spot for Cinn and Acef; respectively, with mean percentage recoveries of 99.18 ± 0.60/99.84 ± 0.53 and 99.19 ± 0.93/99.66 ± 0.58 for method 1 and method 2; consecutively. The two methods are fully validated and proven to be selective, robust and retained their accuracy in up to 50% of Cinn/Acef reported degradation products and Theo. Moreover, the two methods are applied to a coformulated drug product comprising Cinn and Acef showing satisfactory results. Comparison of the obtained results by the proposed methods with that of the reference ones statistically shows no significant differences.

An intelligent approach based on hybrid of principal component analysis-fuzzy inference system-adaptive neuro-fuzzy inference system for the simultaneous spectrophotometric determination of sofosbuvir and velpatasvir as antiviral drugs in pharmaceutical formulation and urine sample

In this study, a simple, fast, accurate, and inexpensive chemometrics-assisted spectrophotometric method was developed for the simultaneous determination of sofosbuvir (SOF) and velpatasvir (VEL) as antiviral drugs. Fuzzy inference system (FIS) and adaptive neuro-fuzzy inference system (ANFIS) along with principal component analysis (PCA) were used for the analysis of SOF and VEL in binary mixtures, pharmaceutical formulation, and urine sample. Root mean square error (RMSE) of FIS model was 0.1518 and 0.075 for SOF and VEL, respectively. Also, the average testing error related to the ANFIS method was achieved 2.23 ​× ​10−5 and 5.58 ​× ​10−6 for SOF and VEL, respectively. The range of mean recovery percentage was between 99.76 and 100.41 for both methods. Relative standard deviation (RSD) of the real sample was lower than 0.06% for FIS and ANFIS for both components. Analysis of variance (ANOVA) was applied to the results of the real sample that there was no significant difference between the suggested approaches. PCA-FIS and PCA-ANFIS as efficient and accurate methods can be useful for the simultaneous estimation of binary and ternary mixtures in quality control of pharmaceutical formulations.

Method Development and Validation of Spectrophotometric Methods for The Estimation of Rizatriptan Benzoate in Pure and Pharmaceutical Dosage Form

Analytical UV derivative spectrophotometric method was developed and validated to quantify Rizatriptan Benzoate in pure drug and tablet dosage form. Based on the spectrophotometric characteristics of Rizatriptan Benzoate, a signal of zero (225nm), first (216nm), second (237nm), third (233nm), fourth (231nm) order derivative spectra were found to be adequate for quantification. The methods obeyed Beer's law in the concentration range of (0.1-360µg/ml) with square correlation coefficient (r2) of 0.999. The mean percentage recovery was found to be 100.01 ± 0.075. As per ICH guidelines the results of the analysis were validated in terms of linearity, precision, accuracy, limit of detection and limit of quantification, and were found to be satisfactory.

Innovative derivative/zero ratio spectrophotometric method for simultaneous determination of sofosbuvir and ledipasvir: Application to average content and uniformity of dosage units

An innovative simple, rapid and sensitive spectrophotometric method was developed for the simultaneous analysis of sofosbuvir (SOF) and ledipasvir (LED) in their combined dosage forms. Sofosbuvir with ledipasvir (SOF/LED) as a combined dosage form was tried at the pandemic COVID 19 crisis. This technique has the advantages of both zero order and first order spectrophotometry. The zero and first derivative amplitudes were measured at 274.2 nm for SOF (zero crossing point of LED in first derivative spectrum) and 314 nm for LED (zero crossing point of SOF in first derivative spectrum) over the concentration range of 2.0–50.0 μg mL−1 with coefficients of determination (R2) > 0.9999 for both drugs and mean percentage recoveries of 100.25 ± 1.61 and 99.85 ± 0.99 for SOF and LED; respectively.This original method was validated according to ICH requirements and statistically compared to published comparison methods. This method was applied to estimate the average content and the uniformity of dosage units of SOF/LED combined dosage form according to British Pharmacopeia requirements.

Stability-Indicating Reverse-Phase High-Performance Liquid Chromatographic Method Development and Validation of Lamotrigine in Bulk and Pharmaceutical Dosage Form

In the current study, analytical method has been validated by system suitability parameters, linearity, accuracy and percent recovery, precision, ruggedness, robustness, limit of detection, and limit of quantification. The present study of lamotrigine was achieved using Cosmosil C18 (250 nm×4.6 ID, particle size: 5 Micron) Column with mobile phase methanol: water (60:40) pH: 3 at a flow rate 0.8 ml/min with UV detection at 308 nm. The retention time for lamotrigine was found to be 4.979 min. In linearity, the correlation coefficient (R2) for lamotrigine was found to be 0.999, slope is 39,801, and intercept was found to be 51,862 which are well within the acceptance criteria. The mean percent recovery for lamotrigine at three different levels for 50%, 100%, and 150% was found to be 99.28%, 99.30%, and 100.40%. The % RSD should not more than 2%. In precision study, interday (RSD is 0.41%) and intraday (RSD is 0.26%) are found. Forced degradation experiments were carried out by exposing standard form of lamotrigine for acid-base, oxidative, photolytic, and thermal stress conditions. Hence, the developed method is accurate, precise, repeatable, and reproducible and can be used for routine analysis of lamotrigine.

Application of Response Surface Methodology in Development and Optimization of Stability Indicating RP-HPLC Method for Determination of Tolvaptan in Bulk and Formulation

Design of Experiment assisted stability indicating RP-HPLC was developed and optimized using response surface methodology for determination of Tolvaptan. Mobile phase was developed and optimized using Design of Experiment with response surface methodology. Acetonitrile and phosphate buffer with pH 5.5 (70:30% V/V) was optimized as mobile phase. The flow rate was maintained at 1ml/min. Stress studies were performed as per guidelines. Method was validated in accordance with regulatory requirements and results were within specified limits of regulatory guidelines. Tolvaptan was eluted at 3.24 min. It shows linearity from 2.5-15 µg/ml. Coefficient of correlation was 0.999, LOD and LOQ values were 1.0871 (µg/ml) and 3.2942 (µg/ml). Precision was determined with % RSD of 0.8669 and 0.9709%, mean percentage Recovery value was found to be 99.88 ±1.2. All stress degradation products are very well resolved from drug peak which indicate suitability indicating nature of the developed method. Design of Experiment technique can help in fast and economical optimization of mobile phase which inturn will save time for method development. The developed method is simple, accurate, sensitive which can be utilised as stability indicating method for identification of degradation products in routine analysis of the drug.

Rapid simultaneous quantitative determination of linagliptin and empagliflozin as antidiabetic drugs using spectrophotometric method based on fuzzy systems and radial basis function neural network in tablet formulation and biological sample

In this study, spectrophotometry method was combined with artificial intelligence techniques for developing a simple, rapid, low-cost, and accurate approach for the simultaneous determination of Linagliptin (LIN) and Empagliflozin (EMPA) as antidiabetic drugs in mixtures and pharmaceutical formulation. Fuzzy inference system (FIS), adaptive Neuro-fuzzy inference system (ANFIS), and radial basis function neural network (RBF-NN) were proposed to predict the concentration of pharmaceutical components. The mean recovery and root mean square error (RMSE) of FIS were 98.44%, 103.50% and 0.0668, 0.1982 for LIN and EMPA, respectively. The mean recovery percentage of 100.07 and 99.83, as well as RMSE of 0.0033 and 0.0176 were obtained for LIN and EMPA, respectively. On the other hand, MSE related to the RBF-NN was found 1.46 × 10−26 and 1.72 × 10−25 for LIN and EMPA, respectively. Analysis of variance (ANOVA) test did not show a significant difference between high-performance liquid chromatography (HPLC) and proposed methods. The mean recovery (between 91.40% and 98.29%) and relative standard deviation (RSD) (lower than 0.5%) revealed that the suggested methods in a complex matrix such as urine had good predictive ability. Due to the obtained results, these methods can be used in quality control.

L and D enantiomer binary mixture determination simultaneously by spectrophotometric method without separation step based on artificial neural network and least squares support vector machine in valsartan pharmaceutical production

In this study, spectrophotometry method as a quick, simple, and accurate approach was proposed for the simultaneous determination of Valsartan (VAL) and its enantiomeric impurity (IMP-A) in binary mixtures using feed-forward artificial neural network (FFANN) with backpropagation learning algorithm and least squares support vector machine (LS-SVM) techniques without using excess solvent and the time-consuming extraction phase. Two different algorithms, including Levenberg–Marquardt (LM) and scaled conjugate gradient (SCG) as training algorithms was used in ANN method. LM algorithm with 2 layers, 9 neurons and 2 layers, 7 neurons in the FFNN with the mean square error (MSE) of 2.84 × 10−11 and 5.08 × 10−12 had the best response for predicting VAL and IMP-A concentrations, respectively. By optimizing regularization parameter (γ) and width of the function (σ) in LS-SVM model, mean recovery percentage and root mean square error (RMSE) were obtained 98.61, 98.95 and 3.22 × 10−4, 2.89 × 10−4 for VAL and IMP-A, respectively. The achieved results from the commercial tablet (Adovan) analysis using the proposed methods were compared to the yielded by HPLC technique via one-way analysis of variance (ANOVA) test. According to the results, they revealed good agreement and there was no significant differences.

Sensitive and validated TLC densitometry method coupled with fluorescence detection for quantitative determination of the newly co-formulated drugs, celecoxib and amlodipine besylate in tablet dosage form

Abstract New, sensitive, rapid, cost-effective, and validated stability-indicating thin layer chromatographic (TLC) method coupled with fluorescence (FL) detection was developed for the quantitative analysis of celecoxib (CEL) and amlodipine besylate (AMLO) in their laboratory prepared binary mixture using the non-fluorescent TLC silica gel 60 plates. Ethyl acetate: diethylamine: 1-propanol (9:1:0.2, V/V) was used as a developing system. The retention factor (Rf) for each drug was 0.80 ± 0.03 and 0.44 ± 0.01 for CEL and AMLO, respectively. The plates were excited at 264 nm for the simultaneous FL measurement of CEL and AMLO, the calibration curves were linear over a concentration ranges of 30.0–300.0 ng/band and 15.0–150.0 ng/band with mean percentage recoveries of 99.80 ± 0.85 and 99.80 ± 0.77 For CEL and AMLO, respectively. The developed method was applied for the stability studies of the cited drugs in their laboratory prepared binary mixture and the forced degradation products were determined when present in presence of the pure drugs so the method can be considered as a stability-indicating one and it was validated as per ICH guidelines and proved to be accurate and precise.

A Double Divisor Ratio-Spectra Derivative Method for the Ternary Mixture of Aspirin, Clopidogrel Bisulphate and Rosuvastatin Calcium

Quantitative analysis of formulation containing Aspirin, Clopidogrel Bisulphate and Rosuvastatin Calcium were performed using double divisor ratio spectra derivative method. Detection wavelength for Aspirin, Clopidogrel Bisulphate and Rosuvastatin Calcium was 240.2 nm, 231.8 nm and 263.2 nm respectively. The linearity range for all three drugs was 2-20 μg/mL and it was validated through regression analysis and residual analysis. Mean percentage recovery was 100.09 %, 100.60 % and 99.86 % for Aspirin, Clopidogrel Bisulphate and Rosuvastatin Calcium respectively. The developed method was validated according to International Council for Harmonization guidelines and validation approach is much more justified than the usual approach. The use of advanced statistical tools for validation ensures the efficiency; quality and reproducibility of our method. Obtained results were satisfactory and ensured the quality and reproducibility of the method.

A VALIDATED TLC- DENSITOMETRY FOR THE SIMULTANEOUS DETERMINATION OF TAMSULOSIN AND DUTASTERIDE IN THEIR COMBINED PHARMACEUTICAL FORMULATION.

A TLC densitometric method was developed and validated for simultaneous determination of dutasteride and tamsulosin in their challenging combined pharmaceutical formulation, where the separation process was achieved using a mobile phase composed of ethyl acetate: methanol: hexane: ammonia (90: 5: 3: 2 by volume) on pre-coated silica gel (60 GF254) plates, densitometric quantification was performed at 270 nm for both drugs. TAMS and DUTA were resolved with Rf values of 0.57± 0.01 and 0.72 ± 0.01 with a mean percentage recovery of 100.51 ± 0.659 and 100.81 ± 0.743, respectively. Method validation was performed following the International Conference on Harmonization (ICH) guidelines and was victoriously applied for simultaneous determination of tamsulosin HCl and dutasteride in their pharmaceutical formulation. The acquired results of the Proposed method were statistically compared with those acquired by the reported methods, demonstrating no significant difference. Therefore, the proposed method has the potential for being fast, simple, economic, and selective for sustainable analysis of the cited drugs.

Development and Validation of Novel Gas Chromatography (GC) and Thin Layer Chromatography (TLC) Densitometry Methods for the Quantification of Stigmasterol 3-O-β-D-Glucopyranoside (S3G) in Balanites Aegyptiaca Extract: Application to Newly Formulated Balanites Capsules

Balanites aegyptiaca is a commonly used antihyperglycemic in Egyptian folk medicine. The objective of the present study is to develop two chromatographic methods for standardizing the Balanites extract by quantification of its main component, stigmasterol 3-O-β-D-glucopyranoside (S3G). The first method is gas chromatography (GC) where nitrogen was adopted as the carrier gas. The second method was thin layer chromatography (TLC) densitometry where chromatographic separation was established on aluminum plates using chloroform; methanol was used as the mobile phase followed by a densitometric measurement at 254 nm. Validation of the proposed methods was applied per International Council for Harmonization (ICH) guidelines. Both methods were adopted for quantification of S3G in Balanites capsules. The standard calibration curve was established for S3G in the concentration range of 10–130 μg/mL and 0.5–7.5 μg/mL for the GC and TLC methods, respectively. A good linearity with a correlation coefficient of 0.999 was obtained for both methods. Furthermore, the mean percentage recovery was found to be 99.46% for GC and 100.67% for TLC. Good precision was achieved, with relative standard deviation values &lt;1%, and finally, the limits of detection and quantification were 2.51 and 7.59 μg/mL for GC and 0.13 and 0.40 μg/mL for TLC, respectively.

Investigation of the fluorescence of benoxinate for facile determination in pure form, eye drops and aqueous humor

A new approach to determine the local anesthetic benoxinate spectrofluorimetrically was developed. It was found that benoxinate exhibits strong native fluorescence in ethanol at 371 nm after excitation at 297 nm. There was a linear response between the fluorescence intensity and the concentration of the studied drug over the range of 10.0–100.0 ng/ mL. The suggested spectrofluorimetric method was optimized and validated following the pharmacopoeial guidelines. The obtained results were fully discussed and statistically analyzed in relevance to a previous published spectroscopic method. The limit of quantification (LOQ) of the present method was 1.79 ng/mL. Inter-day and intra-day precision relative standard deviations were lower than 1.5%.Finally, the proposed methodology has been adopted for determination of benoxinate in aqueous humor with a mean percentage recovery 99.87 ± 1.66 as well as in the pharmaceutical eye drops with a mean percentage recovery 100.37 ± 1.32. The method is cost-effective and green as it depends in water and ethanol mainly.

Microanalysis of Two Members of Oxicam Drugs by Quenching the Fluorescence of Newly Isolated Carbonaceous Materials From Incense Ash.

For the first time ever, useful fluorescent (FL) carbonaceous materials (CMTS) were isolated from incense ash using facile procedure on two steps; dispersion of the CMTS in water followed by filtration. The CMTS were characterized using the following techniques; dynamic light scattering (DLS), transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) spectroscopy. The CMTS exhibit excitation wavelength dependent fluorescence emission, so it can be used as a FL probe. The FL probe was employed for sensing and quantitative determination of two members of oxicam family (tenoxicam (TEN) and meloxicam (MEL)) that belongs to non-steroidal anti-inflammatory drugs (NSAIDs). The method is based on the quenching of the FL intensity of the isolated CMTS by inner filter effect mechanism (IFE). The FL intensity decreases in linear relationship with increasingthe concentrations of the two cited drugs within the range of 4.0 - 30.0µg/mLwithmean percentage recoveries of 100.04 ± 0.95 and 100.07 ± 1.06 with detection limits of 1.31µg/mL and 1.06µg/mL for TEN and MEL, respectively. Finally, the developed sensing system was validated as per ICH guidelines and it was proved to be accurate and precise and applied successfully for quantitative determination of the two cited drugs in their capsule dosage forms with excellent percentage recoveries reaching to 97.66 ± 0.39and 98.19 ± 1.12 for TEN and MEL, respectively.

The feasibility of ultrasound-assisted endovascular laser thrombolysis in an acute rabbit thrombosis model.

This study aimed to test the feasibility of combined ultrasound and laser technique, namely, ultrasound-assisted endovascular laser thrombolysis (USELT), for thrombolysis by conducting in vivo tests in a rabbit thrombosis model. An acute thrombus was created in the right jugular vein of rabbit and then was treated with ultrasound only, laser only, and USELT to dissolve the blood clot. A total of 20 rabbits were used. Out of which, the first three rabbits were used to titrate the laser and ultrasound parameters. Then, five rabbits were treated with ultrasound only, five rabbits were treated with laser only, and seven rabbits were treated with USELT. During USELT, 532-nm laser pulses were delivered endovascularly directly to the clot through a fiber optic, and 0.5MHz ultrasound pulses were applied noninvasively to the same region. A laser fluence of 4 to 12mJ/cm2 and ultrasound amplitude of 1 to 2MPa were used. Recanalization of the jugular vein was assessed by performing ultrasound Doppler imaging immediately after the treatment. The maximum blood flow speed after the treatment as compared to its value before the treatment was used to calculate the blood flow recovery in vessel. The blood flow was fully recovered (100%) in three rabbits, partially recovered in two rabbits (more than 50% and less than 100%) with mean percentage recovery of 69.73% and poorly recovered in two rabbits (<50%) with mean percentage recovery of 6.2% in the USELT group. In contrast, the treatment group with ultrasound or laser alone did not show recanalization of vein in any case, all the five rabbits were poorly/not recovered with a mean percentage recovery of 0%. The USELT technology was shown to effectively dissolve the blood clots in an acute rabbit jugular vein thrombosis model.