Formulation Development, Characterization and In-vitro Evaluation of Tamoxifen Loaded Liposomes

Background: The study was aimed to prepare and evaluate tamoxifen loaded controlled release liposomes to reduce the side effects of tamoxifen during cancer treatment. Methods: Different tamoxifen loaded liposomes were prepared by modified ether injection (MEIM) and thin film hydration method (TFHM) under prescribed conditions. The prepared liposomes were characterized by using optical microscopy, evaluating encapsulation efficiency, in-vitro and ex-vivo diffusion studies by using dialysis membrane and chicken intestinal sac respectively.Results: The data revealed that all of the liposomes were spherical in shape and stable under three physical conditions i.e. 4, 25 and 37 ± 2°C temperatures and 60 ±5% relative humidity. Additionally most of the liposomes followed zero order and class II release kinetics. It was also observed that with the increase of phospholipids and cholesterol, entrapment efficiency of liposome vesicles increased thus giving a controlled release drug delivery system but further increase reduced this efficiency at a certain level.Conclusion: The formulated control release liposomes might be a good drug delivery system for target oriented drug delivery with minimum side effects of tamoxifen during cancer treatment

Formulation And Evaluation Of Controlled Release Maintenance Dose Loaded Niosomes Of Anti-Hypertensive Drug

The present study was aimed to formulate, comparatively evaluate and optimize multiple lipid drug carriers of valsartan for oral controlled release to overcome the problems associated with the drug such as bioavailability, to reduce the dosage regimen, half life and to determine the appropriateness of niosomal formulation as a drug carrier. Ether injection method was chosen for the formulation of physically and chemically stable niosomes of valsartan. The formulation and process parameters were optimized by manufacturing placebo niosomes. Than drug loaded niosome was prepared by varying the concentration of span 60. The prepared nine formulations were evaluated for various parameters. Placebo niosomes were evaluated for appearance, odour, texture, creaming volume, pH and changes after 15 days. The medicated nine formulations were evaluated for organoleptic properties (appearance/color, odour), pH, total drug content, entrapment efficiency, mean particle size and polydispersibility index, zeta potential and In-vitro drug release. All formulations were off-white in color, odourless, and fluid in nature. It was stable and did not show sedimentation. The pH was found to be in the range of 4.6-5.4. Drug content was found in the range of 89.13 to 99.52. The Entrapment efficiency was found in range of 79.05 to 98.24. The mean vesicle size of drug loaded niosomes of the different batches ranged between 2.52-3.42μm. The polydispersvity index was in the range of 0.325 to 0.420 which indicates a narrow vesicle size distribution. The values of zeta potential were in the range of -20.29 mV to -30.55 mV which indicates that niosome had sufficient charge and mobility to inhibit aggregation of vesicles. All the nine formulations shows constant drug release in controlled manner up to 24 h. Formulation V7 was considered to be the best formulation as the % drug content (99.52 ± 0.97), % entrapment efficiency (98.24 ± 1.50) and % drug release at the end of 24th h (98.55) were high for V7. The optimized formulation V7 showed higher degree of correlation coefficient (r2) 0.9805 which indicates process of constant drug release from dosage form. The present study concludes that the prepared niosome is a convenient and efficiency carrier for the delivery of antihypertensive drug. Besides this, it provided controlled delivery of drug.

Preparation technology of sinomenine hydrochloride liposomes / 中草药

Objective: To prepare sinomenine hydrochloride (SIN-HCl) liposomes with high entrapment efficiency (EE) and to illustrate the effects of drug quantity and particle size on EE. Methods: Centrifugation sedimentation-centrifugation ultrafiltration was employed to determine EE of liposomes. Thin film hydration (TFH), reverse phase evaporation (REV), and ether injection (EI) were screened based on EE and formability of liposomes. The effects of water type, pH value, ion concentration of hydration liquid, pH gradient active drug loading, lecithin-cholesterol ratio, and drug-lipid ratio on EE of liposomes were investigated. The relationship between EE and the factors affecting the drug quantity and particle size was probed with a comprehensive design experiment. The stability of typical liposomes was evaluated at 4 °C. Results: The optimal preparation technology was TFH for SIN-HCl liposomes and citrate buffer solution (CBS) was the best hydration liquid. The liposome EE increased with the increase of pH values of CBS. When the pH value of CBS was fixed, the EE increased as a result of decrease in the ion concentration of CBS. pH gradient active drug loading led to increase of EE. The preferable hydration liquid for liposomes was CBS with pH value of 2.5. The optimal ratio of soybean lecithin to cholesterol was 6:1. Increasing ratios of SIN-HCl to soybean lecithin from 1:6 to 6:6 led to a slight decrease in EE of liposomes without probe signification. A quantitative relationship was established between the EE and drug quantity and liposome size. The EE of SIN-HCl liposomes prepared by certain particle size and drug quantity could reach over 80%. The typical liposomes showed a good stability. Conclusion: The technology of pH gradient active drug loading is able to prepare SIN-HCl liposomes with high EE.

Niosomal drug delivery system: The magic bullet.

The concept of drug targeting or site specific drug delivery was introduced first time by Paul Elrich in 1909, when he reported ‘magic bullet’ to deliver a drug to the desired site of action without affecting the non target organs or tissues (Juliano, 1980) by associating the drug with a pharmacologically “inactive carrier” capable of conveying the drug selectively towards its target cells. The methods of preparation of niosomes such as hand shaking, ether injection and sonication (developed on the basis of liposome production technique) have been reviewed by Khandare et al., 1994. The hand shaking method form vesicles with greater diameter [0.35 – 13􀀀m] as compared to those prepared by ether injection method [50-1000nm]. The film formation method was used for the preparation of the niosomes due to simplicity, reproducibility and high drug entrapment efficiency.