Supplementary Information: The online version contains supplementary material available at 10.1186/s13765-021-00639-w.
EXPERIMENTAL PROCEDURE: The microbial limit test (MLT) studies indicated the suitable dosage of minimum and maximum gamma irradiation for leaf extracts as well as dried leaves of all the tested medicinal plants. Quantitative analysis of total phenolic content (TPC) analysis is based on calorimetric measurements determined using the Folin-Ciocalteu reagent with gallic acid (GA) used as the reference. In vitro cytotoxicity assay by using fibroblast (L929) cell lines was performed on each plant to determine the toxicity effect which sodium dodecyl sulfate (SDS) as the positive control. DPPH (2,2-diphenyl-1-picryl-hydrazyl) assay was conducted by using vitamin C and GA as the positive controls to determine the antioxidant property of each plant.
RESULTS AND CONCLUSION: The MLT analysis indicated that the suitable dosage gamma irradiation for leaf extracts was 6-12 kGy and dried leaves were 9-13 kGy. The amount of GA concentration in each plant increased significantly from 30-51 mg GAE g-1 before treatment to 57-103 mg GAE g-1 after treatment with gamma radiation. This showed no significant effect of in vitro cytotoxicity activity before and after treatment with gamma irradiation in this study. Effective concentration (EC50) values of Khaya senegalensis plant reduced significantly (P ≤ 0.005) from 44.510 μg/ml before treatment to 24.691 μg/ml after treatment with gamma radiation, which indicate an increase of free radical scavenging activity.
METHODS: Bilosomes formulations were optimized statistically for the outcome of vesicle shape, size, and entrapment efficiency using two types of bile, i.e. sodium taurocholate and sodium cholate. These bilosomes were then loaded into HPMC base gel and further characterized for their morphology, drug content, pH, viscosity, spreadability and eventually ex-vivo skin penetration and deposition studies.
RESULTS: Findings showed that sodium cholate has superiority as a penetration enhancer over sodium taurocholate in terms of morphological characterizes, zeta potential, and cumulative amounts of tamoxifen permeated per unit area (15.13 ± 0.71 μg/cm2 and 6.51 ± 0.6 μg/cm2 respectively). In fact, bilosomes designed with sodium cholate provided around 9 folds of skin deposition compared to TXN non-bilosomal gel.
CONCLUSION: Bilosomes gels could be a promising option for locally delivering tamoxifen to the breast through the skin, offering an encouraging transdermal solution.
SIGNIFICANCE: The significance of this research was to successfully incorporate slightly water soluble and potent anticancer drug (cisplatin) into cubosomes, which provide slow and sustained release of drug for longer period of time.
METHODS: The delivery system was developed through top-down approach by melting GMO and poloxamer 407 (P407) at 70 °C and then drop-wise addition of warm deionized water (70 °C) containing cisplatin. The formulation then exposed to probe sonicator for about 2 min. A randomized regular two level full factorial design with help of Design Expert was used for optimization of blank cubosomal formulations. Cisplatin loaded cubosomes were then subjected to physico-chemical characterization.
RESULTS: The characterization of the formulation revealed that it had a sufficient surface charge of -9.56 ± 1.33 mV, 168.25 ± 5.73 nm particle size, and 60.64 ± 0.11% encapsulation efficiency. The in vitro release of cisplatin from the cubosomes at pH 7.4 was observed to be sustained, with 94.5% of the drug being released in 30 h. In contrast, 99% of cisplatin was released from the drug solution in just 1.5 h. In vitro cytotoxicity assay was conducted on the human lung carcinoma NCI-H226 cell line, the cytotoxicity of cisplatin-loaded cubosomes was relative to that of pure cisplatin solution, while blank (without cisplatin) cubosomes were nontoxic.
CONCLUSIONS: The obtained results demonstrated the successful development of cubosomes for sustained delivery of cisplatin.