Development and Validation of UV-Vis Spectrophotometric Method for Estimation of Black Seeds and Peppermint Oil in Emulsion

The purpose of the study was to develop and validate UV-Vis spectrophotometric method for estimation of black seed oil (BSO) and peppermint oil (PO). Emulsions were prepared using alginate (2.0 %) w/v as water phase and lecithin (3.0 %) w/v by incorporating BSO and PO oil separately. A good linearity result was recorded with R2 value at 0.9990 within the concentration range of 5.0-50.0 mg/ml for both oils. Moreover, the recovery percentage of accuracy for BSO was from 102.03 ± 0.16 % to 99.67 ± 1.53 % and 101.29 ± 1.94 % to 98.73 ± 1.19 % for PO, which suggests that the method was accurate and precise. The method was precise, as the largest % Relative Standard Deviation ( % RSD) value was 1.77 in intraday and 1.99 in interday for BSO, whereas 1.94 in intraday and 1.96 in interday for PO. The Detection Limit (DL) (0.469 mg/ml) and Quantification Limit (QL) (1.408 mg/ml) for BSO, and DL (0.709 mg/ml) and QL (2.127 mg/ml) for PO were measured. Based on this developed method, the % Encapsulation Efficiency (EE %) of optimized formulation was obtained 89.06 ± 0.39 % (n=3). This protocol may be used for estimation of EE % analysis of new drug formulation in pharmaceutical research and development and quality control analysis.Abbreviations: BSO: Black Seeds Oil; TQ: Thymoquinone; PO: Peppermint Oil; PBS: Phosphate Buffer Saline; N. sativa: Nigella sativa; Neem Seed Oil: NSO; DL: Detection Limit; QL: Quantification Limit; RSD: Relative Standard Deviation; SD: Standard Deviation; ICH: The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use; HPLC: High-Performance liquid Chromatography; GC-MS: Gas chromatography-mass spectrometry; EE: Encapsulation Efficiency; PBS: Phosphate Buffer Saline; EDTA: Ethylenediamine tetraacetic acid; w/v: Weight/Volume; T80: Tween 80.