Structural, Thermal and Surface Properties of a Formulated Sunscreen: Zn/Al-nitrate Layered Double Hydroxide Intercalated with 4-aminobenzoic Acid

Intercalation of 4-amino benzoic acid (4-AB) into Zn/Al-nitrate layered double hydroxide (ZAL2) to form Zn/Al-4AB (ZALAB) compound was successfully synthesized from nitrate salt by using direct co-precipitation method. ZALAB compound was confirmed by Powder X-ray diffraction (PXRD) pattern with a basal spacing of 15.3 Å. The presence of COO- and C6H5NH2 functional groups of 4-AB at 1,517 and 1,178 cm–1 in Fourier transform infrared (FTIR) spectrum reinforced 4-AB intercalated into the resulting compound. Based on the thermal analysis, 4-AB in ZALAB compound was more stable compared to pure 4-AB. Breuneur, Emmet and Teller/Barret-Joyner-Halenda (BET/BJH) analyses demonstrated that ZALAB compound is a mesopores-type IV compound with 4.25 m2/g surface area. This material is an irregular shape with different sizes of particles. ZALAB is a potential sunscreen formulation that minimizes the harmful effect on the skin, improving pharmaceutical technology in the skincare treatment.HIGHLIGHTS4-amino benzoic acid (4-AB) is a sunscreen composed of carboxylic and aromatic groups that potentially filter UV-B radiationLayered double hydroxide (LDH) is known as an ionic clay that is based on the brucite (Mg (OH)2) -like cations layers containing intercalated charge-balancing anions and waterIntercalation of 4-amino benzoic acid (4-AB) into Zn/Al-nitrate layered double hydroxide (ZAL2) to form Zn/Al-4AB (ZALAB) was synthesized using direct co-precipitation methodZALAB material has a higher thermal stability compared to 4-AB in pure formGRAPHICAL ABSTRACT