Gel growth and characterization ofβ -DL-methionine

Screening of the Chemical Composition and Identification of Hyaluronic Acid in Food Supplements by Fractionation and Fourier-Transform Infrared Spectroscopy

Hyaluronic acid, together with collagen, vitamins or plant extracts, is a part of many cosmetic and food preparations. For example, this polysaccharide is used in formulation of many food supplements due to its protective effects on human health. In this work, the screening of the chemical composition of three chosen dietary supplements (powder, tablets and capsules) containing hyaluronic acid was carried out using Fourier-transform infrared spectroscopy. Because of the low amount of analyte in all these samples, it was isolated or concentrated prior to the analysis using a suitable sequential fractionation protocol. Individual isolation procedures were established for each sample based on their declared composition. Firstly, the major components such as collagen or vitamins were removed to obtain polysaccharide fractions by the enzymatic treatment and/or washing out with the appropriate solvents. In some cases, the water insoluble part was removed from the rest dissolved in water. Then, hyaluronic acid was precipitated with copper(II) cations and thus separated from the other polysaccharides. Finally, the analyte was identified in the enriched fractions by the characteristic vibrational bands. The amount of hyaluronic acid in the purified fractions was determined in three ways: gravimetrically, spectrophotometrically, and using isotachophoresis. The combination of the appropriate preparative and analytical steps led to the successful evaluation of chemical composition, finding and quantification of hyaluronic acid in all the studied samples.

Detoxification of poly(methyl methacrylate) bone cement by natural antioxidant intervention

Poly(methyl methacrylate) (PMMA) bone cement is the most widely used grouting material in the joint arthroplasties and vertebroplasties. The present investigation has been carried out to scavenge the radicals and monomer by addition of an antioxidant to minimize the toxicity of bone cement (BC). The in silico studies were employed to determine the potent natural antioxidant at physiological conditions. The antioxidant methionine demonstrated a strong binding affinity with free radicals and methyl methacrylate (MMA) monomer than cysteine. The designated amount of methionine was optimized by various assay methods and >2% methionine shows strong scavenging capacity in BC. Moreover, the antioxidant-loaded BC (ABC) demonstrated similar handling, physicochemical and mechanical properties to pristine bone cement. Significantly, the developed formulation shows superior biological characteristics such as cell proliferation (2 ± 1 BC and 6 ± 1 ABC), adhesion (0.32 ± 0.02 BC and 0.54 ± 0.01 ABC), and cell viability (81 ± 2% BC and 93 ± 1% ABC) toward human osteoblast-like cells (MG-63). Therefore, the novel antioxidant bone cement is a potential candidate for various orthopedic applications to eliminate the adverse effects, related to residual toxic radical and monomer in bone cement.

Growth of bulk single crystal of N-acetyl DL-methionine and its spectral characterization

Bulk size single crystal of N-acetyl DL-methionine (C7H13NO3S) (1) was grown using a home-made crystal growth setup (MKN setup). The identity of the grown crystal was confirmed by single crystal X-ray diffraction. The modes of vibrations of the functional groups present were assigned using the infrared (IR) spectrum. UV-vis-NIR spectra showed that the crystals have excellent transparency in the visible and infrared regions. The thermal stability and decomposition of the sample was studied by using thermal analysis (TGA/DTA). Photoluminescence excitation studies showed that the emission occurred at 350 nm for the compound.