User:Madeleine Y. Bee/Notebook/CHEM-582 Experimental Chemistry II/2015/04/03

PVA-Alg Bead Synthesis

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April 3, 2015 absorption FTIR large scale synthesis Procedure Procedure adapted from | Kuo-Ying Amanda Wu and Keith D. Wisecarver (1992), | Idirs et al. and Hydrolysis of liquid pineapple waste by invertase immobilized in PVA–alginate matrix<br.> <br.> PVA-Alg-NaMT Prepare an aqueous solution of 13% PVA and 0.02% sodium alginate at 60°C (Stir plate on 3rd setting: ~68°C) 1 g of PVA and 0.16 g of sodium alginate in 7 mL of water (12.5% PVA and ~0.02% alginate) Add alginate while stirring PVA-water solution ~0.1 g of NaMT should be added to this mixture where applicable Cool dissolved and mixed solution to 35°C Prepare 210 mL of citric acid, calcium chloride solution Add 12 g (5%) citric acid Add 8.4 g (4%) calcium chloride Heat solution to 40°C while stirring Add the PVA-Alg-Nanocomposite mixture to a 10 ml syringe, carefully removing all air before tightening on the syringe tip Place the loaded syringe on the syringe pump, positioning the needle tip over the edge of the prepared citric acid/calcium chloride solution Set the syringe pump and press "run." The PVA solution will be added drop-wise to the cross-linking reaction mixture. Allow solution to cool to room temp while stirring for another 20 min Stir in 24 g (10%) citric acid solution for 30 min Stir in 14.9 g (0.5 M) sodium sulfate solution for 10 min Rinse with water to remove excess reactants Allow beads to dry in teflon plate overnight Clean syringe Pass syringe tip over flame, solution will burst out Use syringe to push water through tip to get any remaining solution out Rinse again with water until solution runs clear <br.> <br.> Malachite Green for Absorption 2000 ppm stock actual concentration (calculated): 1523 ppm 0.5253 mL 1523 ppm stock in 10 mL to make 80 ppm solution 152.3 ppm stock from last time to make 200 ppm solution 52.53 uL 152.3 ppm stock in 10 mL to make 8 ppm solution 0.1313 mL 152.3 ppm stock in 10 mL to make 2 ppm solution <br.> <br.> Rhodamine 6G for Absorption 1 mL 1 mM R6G in 5 mL to make 0.02 mM solution Measurements PVA: Alg: NaMT: citric acid: CaCl2 citric acid: sodium sulfate: Notes beads rehydrate so quickly! run at least one XRD sample at VERY high resolution with expanded range run XRD of plain PVA (20-25), Alg, and NaMT (8, 6 > when inter-colated; we have: 8.5, 20, 28, 35.5) look up pure PVA crystalline XRD to see if we have any in our structure Imaging of R6G beads observation of absorption beads: about half the beads absorb malachite green/R6G (seen by color change) and half remain white. the beads that absorb float while the one that don't sink.