Current study was conducted to assess distinct characteristics of Lallemantia royleana (balangu) seeds mucilage as pH sensitive biomaterial for nanoparticles formulation and its comparison with synthetic polymer-based nanoparticles. Lallemantia royleana (balangu) seeds mucilage was used to prepare pH responsive nanoparticles of an acid-labile drug, dexlansoprazole by using ionic gelation method. Eudragit RS 100 was also used in the preparation of dexlansoprazole nanoparticles by the solvent evaporation method. Nanoparticles were appraised to determine the particle size, zeta potential, polydispersibility index (PDI), and drug entrapment efficiency (EE) and also evaluated by SEM, FTIR, PXRD and thermal analysis. The BSM nanoparticles were in the size range of 451.7 to 972.4 nm with zeta potential –29.4–34.2, Eudragit RS100 nanoparticles size range was 265.3 to 302 nm with + 37.4 to + 40.6 zeta potential. The entrapment efficiency of the BSM nanoparticles and Eudragit RS 100 nanoparticles was in the range of 19.45 to 42.5 and 23.07 to 50.76. FTIR confirmed the compatibility and drug loading in the nanoparticles. SEM results of BSM nanoparticles were smooth and spherical and EudragitRS100 nanoparticles were irregular in shape. Thermal analysis showed that nanoparticles were thermally stable. The maximum drug release from the BSM nanoparticles and Eudragit RS 100 formulations in the acidic pH was 9.76 to 9.83 and 13.50 to 13.89 and in basic medium, respectively. Maximum drug release from the BSM nanoparticles and Eudragit RS100 formulations was 80.47 to 82.04% and 82.30 to 84.13% respectively in 24 h. It was concluded that BSM and Eudragit RS 100 nanoparticles protect the dexlansoprazole from the degradation of acidic pH of the stomach and can be effectively used for the controlled delivery of the drug. [ABSTRACT FROM AUTHOR]