100 ftir

The method of extraction and isolation of the triterpenes from the stem bark of P. longifolia has been previously described [11 ]. Briefly, the powdered plant material was first defatted with n-hexane and then extracted (1:5 w/v) with chloroform. The compounds were isolated from the chloroform extract (13 g) using silica gel column chromatography (24 × 700 mm; Silica gel 60; 0.063 - 0.2 mm; 70–230 mesh ASTM, Merck, Darmstadt, Germany). The column was eluted stepwise with a mixture of n-hexane and ethyl acetate (9:1–3:7) and 20 ml fractions were serially collected. Thin layer chromatography (TLC) (silica gel 60 TLC aluminium sheets 20 cm × 20 cm, F₂₅₄, Darmstadt, Germany) was used to analyse the fractions. The combined fraction 14 was further purified in ethyl acetate to afford the compound (KE1, 1.15 g). Melting point of the compound was determined using Stuart SMP 11 melting point apparatus (Shalom Instruments supplies, Durban, South Africa). Spectroscopic data analysis, NMR (¹H-¹H, ¹³C-¹³C, in DMSO, Bruker 600 MHz), HRMS (in DCM, Waters Synapt G2) and infrared (IR) (Perkin-Elmer 100 FTIR) techniques were used to establish and confirm structure. Chemical shifts were expressed in δ (ppm).

The FTIR spectra of the magnetic NSs were recorded with a PerkinElmer 100 FTIR (Waltham, MA, USA) using an attenuated total reflectance (ATR) accessory. All of the samples were scanned in the 4000–650 cm⁻¹ range at a resolution of 4 cm⁻¹, collecting 8 scans per spectrum.

FT-IR analysis was utilized for the detection of embedded biomolecules which are potentially accountable for the reduction and stability of AgNPs, as well as the surrounding state of the ligands used as a capping agent on top of the NPs [33 (link)]. FT-IR was carried out after bio-reduction by scraping off the residue that was attached to the capping ligand. The dehydrated nanoparticle was further analyzed to identify the functional groups of the biosynthesized AgNPs. The infrared spectra for the samples were achieved using spectrophotometer (Perkin-Elmer 100 FT-IR, Wellesley, MA, USA) which is further equipped with ATR testing accessory.

ATR-FTIR spectra of drugs alone, blank NS and drug-loaded NSs were recorded on PerkinElmer 100 FTIR. Data acquisition was carried out in between 4000–650 cm⁻¹ at a resolution of 4 cm⁻¹ and collected data were analyzed by spectrum software (PerkinElmer, Waltham, MA, USA).

Fourier transform infrared (FT-IR) spectra of the Marula seed husk were obtained using a Perkin Elmer 100 FT-IR (Waltham, MA, USA) with accessories. The spectra were scanned over the wave number range of 4500 to 400 cm⁻¹. An SDT Q600 TGA–DSC analyzer was used to monitor the degradation pattern of the adsorbent. The sample (10 mg) was heated from room temperature (25 °C) to 1100 °C, at a rate of 10 °C/min.