Surface properties of chitosan/montmorillonite films for biomedical applications

In this study, we firstly investigated the surface and protein adsorption properties of montmorillonite (MMT)/chitosan (CS) composite films with various MMT/CS weight ratios for metallic implants coating applications. Bicinchoninic acid (BCA) protein assay results show that the neat CS film exhibits a high concentration of bovine serum albumin (BSA) protein adhesion because the abundant carbonyl and amide functional groups on the surface of the CS film easily form hydrogen bonds with the copious carboxylic acid groups on the surface of the BSA protein. The MMT/CS composite films with MMT/CS = 3, 5, 8, and 10 possess a much lower BSA adhesion concentration than that of the neat CS film, as some of the carbonyl and amide functional groups on the surface of the composite films are replaced by the –Si–O–Si and –Al–O–Al groups. Among these MMT/CS composite films, the film with MMT/CS = 5 exhibits the lowest BSA adsorption concentration because it possesses a higher MMT content than those with MMT/CS = 1 and 3 and a smoother and non-porous surface than those with MMT/CS = 8 and 10. According to our results, MMT/CS composite films with appropriate MMT/CS weight ratios exhibit better surface and protein adsorption properties than neat CS for biomedical applications.

Chitosan Performance Of Shrimp Shells In The Biosorption Ion Metal Of Cadmium, Lead And Nickel Based On Variations pH Interaction

The widespread use of chitosan waste shrimp extract to reduce the toxicity of certain heavy metals can reduce the escalation of the potential threat of environmental pollution. First) shrimp shell processing is intensively done so it is not wasted freely into the environment, second) toxicity of heavy metals decreased significantly with the application of chitosan adsorption method to heavy metals conducted in wider society. Bioadsorption method of heavy metals of ions Cadmium, Lead and Nickel using chitosan begins with insulation chitosan shell chitosan. The isolated chitosan was characterized. The performance of chitosan adsorption the three types of heavy metal tests was determined by chitosan interaction of each metal at varying pH interactions (pH 2-8). Interaction media conditions: 100 mL medium volume, total chitosan used 1 g, contact time 60 min, the heavy metal concentration of 200 μg/g cadmium ion test, Lead ions and Nickel respectively 100 μg/g. Determination of absorbance using Atomic Absorption Spectrophotometer. The measured value of the adsorbent is converted to the maximum chitosan adsorption concentration value. The adsorption capacity of metallic chitosan complex, maximum was achieved for metal Cd2+ at pH 2 of 198.2051 μg/g (99.05 %), metal Pb2+ at pH 4 of 59.3341 μg/g (59.33 %) and metals Ni2+ at pH 7 of 45.1334 μg/g (45.13 %). This result indicates that pH value of interaction media has an effect on chitosan adsorption to heavy metal test with Cd2+ ˃ ˃ Pb2+ ˃ Ni2+ sequence

Natural Zeolite Modification using Dithizone and Its Application as Adsorbent of Cu(II)

Activation of zeolites with dithizone by reflux method was carried out at 50°C for 6 hours and the results were analyzed using FTIR and GSA. Furthermore, the modified zeolite dithizone was used to adsorb Cu2+ metal ions on variations of adsorption time of 5, 10, 15, 30 and 60 min, variation of adsorption pH 2, 3, 4, 5 and 6 as well as variations in concentrations of 250, 500, 1000, 1500 and 2000 ppm. The results showed that there was a vibrational shift and a new peak emerged on the FTIR zeolite activation spectrum and modified zeolite indicating that the dithizone was present in the zeolite. GSA analysis results show that the surface area of activated zeolite is greater than natural zeolite ie 4,205 m2/g and 5,459 m2/g respectively, whereas dithizone-zeolite had a much smaller surface area of 0.925 m2/g. The selectivity of adsorption of activated zeolite to Cu(II) was greater than of dithizone-zeolite. The optimum adsorption contact time was 10 min for dithizone-zeolite and 30 min for activated zeolite. The optimum adsorption pH was at pH 5 for both adsorbents, as well as the optimum adsorption concentration at 250 ppm for both adsorbents.

Komposit Karbon Aktif dari Bahan Serbuk Gergaji Kayu Karet dan Nanomagnetik Fe3O4 + PVDF Sebagai Bahan Penyerap Limbah Cair Berbasis Logam Berat

Research "of Activated Carbon Composite Materials from Rubber wood Sawdust and addition of Fe3O4 +PVDFNano-Magnetic for Liquid Waste Absorbent Materials based Heavy Metal". The study aims to measure the ability of activated carbon from rubber wood sawdust as an adsorbent of heavy metals such as Cu, Cd and Pb. This research was performed with colection and analizing data in the laboratory . The mixing process for carbon powder, nano-magnetic Fe3O4 and PVDF were use a ball-milling instrument for 2 hours. Samples were activated with KOH activating agent and followed by carbonization process at a temperature of 850 ° C. Results of the untreated samples for the liquid waste contain of Cu, Cd, and Pb with concentration of 15.2918 ppm, 5.5444 ppm and 84.9456 ppm, respectively. Once treated with rubber wood based activated carbon the maximum adsorption occurs in time immersion for 2 hours. The maximum adsorption concentration were as high as 7.8964 ppm (48.36%), 5.0067 ppm (9.69%) and 23.6320 ppm (72.17%) for Cu, Cd and Pb, respectively. The next absorption process were followed by combination of activated carbon and nano-magnetic Fe3O4, the result were 0.2592 ppm (98.30%), 4.5189 ppm (18.49%) and 1.1635 ppm (98.63%) for Cu, Cd and Pb. The maximum adsorption concentration after treated with a mixture of carbon powder and nano-magnetic Fe3O4 plus PVDF, for Cu was 0.2843 ppm (98.14%), Cd was 4.6650 ppm (15.86%) and Pb at 0.7574 ppm ( 99.10%). As a conclution can be found the increasing for the heavy metal absorption for every step experiments, and composite activated carbon, nano magnetic Fe3O4 and PVDF was the best asbsorption material for heavy metal ion in the liquid waste.

The Adsorption Capacity, Pore Structure, and Thermal Behavior of the Modified Clay Containing SSA

Sewage sludge ash (SSA) was created by burning municipal sludge. The potential of clay containing 1 or 3 or 5% SSA was assessed for use as a landfill liner-soil material. Batch adsorption, low temperature N2adsorption, and TG-DTA tests were performed to evaluate the adsorption capacity, micropore structure, thermostability, and components of soils under Cr(VI) and Pb(II) chemical solutions. With the increasing amount of SSA in modified clay, the adsorption capacity of Cr(VI) and Pb(II) to the modified clay increases gradually. After absorption, the pore size of modified clay ranges from 2 nm to 8 nm. With the increasing amount of absorption, the pore volume decreases and the specific surface area increases. With the increasing of adsorption concentration of Cr(VI) and Pb(II), the mass loss percentage of modified clay increases to 23.4% and 12.6%, respectively. The modified clay containing SSA may be used as a good barrier material to attenuate contamination of Cr(VI) and Pb(II) in landfills.

Potassium fluoride as a selective moisture trapping agent for SPE-TD-GC-FID determination of volatile organic compounds in air

Anhydrous potassium fluoride has been proposed as a novel selective moisture trapping agent for gas chromatography to remove water vapor during adsorption concentration of low molecular weight volatile organic compounds (VOCs) from moist air.