Enzymatic synthesis of cellulose nanocrystals from lemongrass and its application in improving anti-cancer drug release, uptake and efficacy

The present investigation involved synthesising cellulose nanocrystals (CNC) from the lignocellulosic waste of lemongrass after its oil extraction by employing enzymatic hydrolysis. The obtained CNC were characterised using FTIR, SEM, TEM, TGA, and XRD techniques. Its potential as a drug carrier were investigated towards the poorly soluble anti-cancer drug, i.e., curcumin. In the results, the biodegradability experiment showed optimal behaviour. The CNC drug loading efficiency was (87.5 %). The adsorption of curcumin was best fitted to the Freundlich isotherm, demonstrating multilayer heterogeneous coverage onto the surface of the CNC. FTIR, molecular modelling and docking studies confirmed the effective interaction of curcumin with CNC. The curcumin encapsulated in CNC was found stable up to 24 h and at all physiological pH conditions compared to pure curcumin. At SGF (pH 1.2), the in-vitro release of curcumin from CNC occurred gradually, followed by the controlled release pattern at different pH, i.e., tumour condition (pH 5.3), SIF (pH 6.8) and SBF (pH 7.4). The first order and Hixson Crowell equation are the best fit by the release pattern at pH values of 5.3 and 6.8. The in-vitro MTT and hemolysis assay confirmed the non-cytotoxic effect of CNC in A431 cells and human erythrocytes at different concentrations (∼ 2–10 µg/ml). The in vitro results revealed that the curcumin-loaded CNC showed superior cytotoxicity and increased cellular uptake compared to curcumin alone, whereas CNC was nontoxic. The study concludes that CNC extracted from natural sources could be used as a drug carrier system. [Display omitted] •CUR-loaded-CNC showed controlled release of CUR without initial burst effect.•CUR adsorption on CNC follows Freundlich isotherm model.•At pH values of 5.3 and 6.8, release pattern best fits the Hixson Crowell equation and first order.•The CUR-loaded-CNC showed enhanced cellular uptake compare to CUR alone.