- Products
- Knowledge
- What the experts say
- Application Areas
- Services
- About
- News
- Contact
Application No. | Application area | Thematic Area | Material Type/Product |
---|---|---|---|
1 | Quantum confined Nanowire Host | Electronic/Energy | SBA 15 , SBA 15 Large Pore, SBA 15 small pore |
2 | Heavy metal Ion removal from waste Water | Environmental | SBA 15, SBA 16, MCM 48 |
3 | Phosphate removal from waste Water | Environmental | Metal Doped SBA 15 (PSBA15Ti) |
4 | Removal of VOCs from Indoor air | Environmental/Health | PSS |
5 | Methanolysis of Styrene OxideOxide | Catalysis | Metal Doped SBA 15 (PSBA15Ti) |
6 | Improving the bioavailability of poorly water soluble drug molecules | Drug Delivery/Pharmaceutical formulation | SBA 15 |
7 | Enzyme Encapsulation for bio catalysisatalysis | Catalysis | SBA 15/PSS |
8 | Phospholipid Extraction from biological matrices | Bio-Analysis/Sample Preparation | Metal Doped SBA 15 (PSBA15Ti) |
9 | Incorporation of Spherical Silica Particles in Pervaporation Membranes for the separation of Water from Ethanol | Chemical Separation | PSS |
10 | Direct Air Capture of CO2 by Physisorbent Materials | Energy | SBA 15 |
Table 1 overview of the application areas and thematic areas that mesoporous material may be utilised in.
In recent years indoor air pollution has become a major concern due to its well demonstrated effect on human health. The adverse health effects of indoor air pollution are expected to become more significant as lifestyles are predicted to become even more sedentary. In 2001, this was demonstrated in the national human activity pattern survey (NHAPS), where it was shown that US citizens typically spent 90% of their time indoors. Aldehydes in particular have adverse health effects (eye and lung irritation), and formaldehyde and acrolein are suspected carcinogens. Changes in building design and improved energy efficiency, along with maximising insulation and minimising air exchange, have led to increasingly airtight buildings. Modern synthetic building materials, such as sealants, plastics and solvent-based coatings, have further added to the problem of indoor air pollutants. Volatile organic compounds (VOCs), non-volatile organic compounds (NVOCs) and semi-volatile organic compounds (SVOCs) are of particular concern as indoor pollutants.
Recent work has shown that Porous Silica Spheres (PSS) can be used to efficiently trap various indoor air pollutants, both in a simulated environment and in an indoor environment. The adsorbent was tested at relatively high concentrations (500 ppbV) and flow rates (10 L min_1). It was shown that PSS was found to be more efficient than the commercially available Amberlite XAD-4 resin at trapping non-polar VOCs and significantly more efficient at trapping polar VOCs present in ambient air. PSS adsorbent was shown to trap 100% of the gas phase carbonyl compounds present in a simulation chamber experiment in the first 10 min of sampling, while the XAD-4 resin was shown to have various levels of efficiency ranging from 100 to 8% over the sampling period for the same group of carbonyl compounds. The indoor at trapping polar carbonyls than XAD-4 resin in an indoor environment. Specifically, SSPH was shown to be significantly more efficient than the XAD-4 resin at trapping glyoxal, C5 and C6 unsaturated carbonyls.
Figure 4 shows a trapping efficiency plot for a selection of small carbonyls: acetone, butanal, pentanal and hexanal. The trapping efficiency of the SSPH for each of these compounds was close to 100% after the first 10 min. The XAD-4 resin showed varying trapping efficiency values ranging from 100 to 8% after the first 10 min. However, the trapping efficiency for both sorbents decreased gradually with time due to the progressive saturation of the sorption surface with trapped species[4]
Highly ordered Zirconium and Titanium doped hexagonal MS with Si/Zr and Si/Ti ratios of 40:1 and 80:1 have been used as solid acid catalysts for the methanolysis of styrene oxide in a single-mode microwave reactor.
The catalysts demonstrated excellent substrate conversion, high product selectivity’s and were shown to remain highly active for several reaction cycles. The experimental results clearly show that the zirconium doped mesoporous silica is an efficient catalyst for the liquid phase methanolysis of styrene oxide. The isolation of the products required a simple filtration/evaporation step.
A typical reaction carried out with a 40:1 Si:Zr catalyst in a single-cavity microwave reactor operating at 105 W for 10 min afforded 100% conversion of styrene oxide. The products were 2-methoxy-2-phenylethanol (93%) and phenylacetaldehyde dimethyl acetal (7%).
Recycling studies showed that the catalyst remained highly efficient for at least five cycles, with 95% conversion of styrene oxide on the fifth cycle after the catalyst was subjected to microwave irradiation while suspended in methanol[5].
It has been long established that increasing the effective surface area of a poorly water-soluble drug in contact with the dissolution medium can enhance drug dissolution. This can be achieved by loading drugs onto silica-based ordered MS which are characterised by high surface areas, large mesopore volumes, narrow mesopore size distributions (5–8 nm) and ordered unidirectional mesopore networks. These properties allow for homogeneous and reproducible drug-loading and release.
The release of drug from the silica carrier is a key performance indicator to consider when employing OMMs for drug dissolution enhancement. The in vitro release of drug from drug–silica samples and the dissolution of the starting fenofibrate are shown (Fig. 6). Utilising MS as a carrier material improved the drug dissolution rate for all processed samples [6].
Immobilisation of enzymes can confer a number of advantages including enhanced stability, ease of recovery and re-use and the capability of using the enzyme in solutions such as non aqueous solvents where the enzyme is insoluble. The main dis-advantages of immobilisation is that the activity of the enzyme is usually lowered and the process of immobilisation can add significant extra costs to the process. In addition, immobilisation methods tend to be non-specific and typically the process of immobilisation of a specific enzyme on a support is optimised and developed on a case-by-case approach. Ideally, support materials for the immobilisation of an enzyme should be mechanically and chemically stable, have high surface areas, be easily made at low cost and display low non-specific protein adsorption properties . Immobilisation should occur in a manner which does not compromise the conformation or activity of the enzyme, while diffusion of the substrate and product to and from the active site should not be hindered. MS has been widely used as supports for enzymes and in particular with the view of utilising them as supports for biocatalysis.
Food matrices are famous for being difficult to work with since they contain many unwanted or interfering compounds (i.e. phospholipids), and samples often require a clean-up step combined with extraction prior LC/MS determination. Recently doped MS (SBA 15 doped with Titanium) was used as a dispersive SPE (dSPE) QuEChERS based approach to sample preparation of liver tissues. Titanium doped MS has been utilised sample preparation of biological samples matrices prior to HPLC analysis The doped silica have been showed to have a preferential selectivity for the phospholipid content of certain samples matrices without removing the analyse of interest from the sample.
The doped SBA 15 class sorbents are based on a novel Titanium doped high purity silica. Impregnating or doping the Titanium moiety into the silica framework offers significant advantages over other metal silica hybrid materials (where the metal moiety is attached to pure silica), and conventional silica in terms of robustness and chemical stability.
Results showed that the recoveries from samples processed with the Titanium doped MS were higher than those from samples process with traditional C18 sorbent material. The mean recovery for SiTi-C18 sorbent accounted for 116 % with only 6 % standard deviation and coefficient of variation values while the C18 sorbent provided only 79% recovery with slightly greater standard deviation and coefficient of variation values of 8 % and 9 % respectively. The data is presented in Table 3. The SiTi(4%)-C18 sorbent proved to be more effective than traditional C18 sorbent used in QuEChERS based method for anthelmintics sample preparation in d-SPE format. [8]
Table 3: Recovery data for ovine liver tissue samples comparing C18 and SiTi(4%)-C18 sorbent materials.
C18 | SiTi4%C18 | |||||
---|---|---|---|---|---|---|
Analyte | Mean (n=5) | ±SD | CV% | Mean (n=5) | ±SD | CV% |
Albendazole | 80 | 12 | 15 | 125 | 10 | 8 |
Albendazole-sulphoxide | 71 | 5 | 8 | 99 | 6 | 6 |
Albendazole-sulphone | 81 | 5 | 6 | 121 | 5 | 4 |
Albendazole-amino-sulphone | 61 | 1 | 1 | 78 | 6 | 8 |
Cambendazole | 81 | 4 | 5 | 112 | 8 | 7 |
Fenbendazole | 83 | 10 | 12 | 123 | 9 | 8 |
Oxfendazole | 72 | 4 | 6 | 109 | 7 | 7 |
Fenbendazole-sulphone | 77 | 5 | 7 | 125 | 12 | 10 |
Flubendazole | 78 | 5 | 7 | 121 | 8 | 7 |
Amino-flubendazole | 54 | 2 | 4 | 76 | 6 | 8 |
Hydroxy-flubendazole | 62 | 3 | 5 | 90 | 6 | 7 |
Mebendazole | 76 | 6 | 8 | 124 | 9 | 7 |
Amino-mebendazole | 50 | 1 | 3 | 71 | 5 | 6 |
Hydroxy-mebendazole | 77 | 6 | 7 | 116 | 7 | 6 |
Oxibendazole | 85 | 9 | 11 | 119 | 9 | 8 |
Triclabendazole | 88 | 15 | 17 | 138 | 10 | 7 |
Triclabendazole-sulphoxide | 77 | 6 | 7 | 107 | 1 | 1 |
Triclabendazole-sulphone | 93 | 6 | 7 | 143 | 2 | 1 |
Thiabendazole | 82 | 3 | 3 | 97 | 3 | 3 |
5-hydroxy-thiabendazole | 67 | 3 | 5 | 83 | 7 | 8 |
Levamisole | 78 | 2 | 2 | 96 | 5 | 6 |
Clorsulon | 79 | 5 | 6 | 111 | 0 | 0 |
Closantel | 92 | 10 | 11 | 135 | 7 | 5 |
Morantel | 75 | 1 | 2 | 101 | 7 | 7 |
Niclosamide | 90 | 14 | 15 | 124 | 8 | 6 |
Nitroxynil | 59 | 3 | 5 | 79 | 1 | 1 |
Oxyclozanide | 85 | 9 | 10 | 107 | 3 | 3 |
Rafoxanide | 87 | 18 | 21 | 139 | 9 | 7 |
Monepantel | 99 | 10 | 10 | 128 | 6 | 4 |
Monepantel Sulphone | 95 | 8 | 9 | 127 | 6 | 4 |
Abamectin B1a | 100 | 23 | 23 | 137 | 2 | 1 |
Doramectin | 93 | 18 | 19 | 133 | 6 | 4 |
Emamectin B1a | 78 | 11 | 14 | 132 | 8 | 6 |
Eprinomectin B1a | 79 | 18 | 23 | 175 | 10 | 6 |
Ivermectin B1a | 89 | 11 | 13 | 117 | 6 | 5 |
Moxidectin | 89 | 13 | 15 | 157 | 8 | 5 |
Overall | 79 | 8 | 9 | 116 | 6 | 6 |
Pervaporation is a membrane separation technology primarily used to dehydrate and recover solvents and also to separate organic–organic mixtures.
It has significant advantage over other separation techniques in that it can be used to effectively ‘break’ azeotropes of mixtures without any of the typically associated physical difficulties and negative environmental impacts of techniques such as azeotropic distillation.
One method of improving membrane flux without significantly compromising selectivity is by inclusion of porous particles into the polymer matrix, e.g. zeolites and silica particles. In porous ceramic–polymer membrane hybrids of this type the engineering of the particles, i.e. size, shape, monodispersivity, pore size and surface chemistry, is of significant importance.
Recent work has shown that the incorporation of engineered PSS into polymer pervaporation membranes can be highly beneficial.
Results show that incorporation of spherical discreet, size-monodisperse mesoporous silica particles of 1.8–2μm in diameter and with pore diameters of 1.8 nm, when incorporated into a poly (vinyl alcohol) [PVA] polymer to produce composite pervaporation membranes, resulted in statistically significant increases in both flux and selectivity. Unlike zeolitic systems, PSS can be very controllably engineered to give a wide range of pore sizes and chemistries and may provide new generations of membranes for various pervaporation applications.[9]
Sequestration of CO2, either from gas mixtures or directly from air (direct air capture, DAC), could mitigate carbon emissions. The development of a new generation of porous materials iskey to enabling the “age of gas”, wherein new technologies develop around the use of gases.[10] Carbon dioxide (CO2) represents a topical challenge in this context: anthropogenic emissions of CO2 are accepted as a significant risk to global climate; CO2 is an undesirable component of commodities such as natural gas and biogas. Recent work has shown that amine functionalised SBA 15out performed Metal Organic Framework (MOF) and Zeolite benchmark materials.
Temperature programmed desorption (TPD) experiments are presented in Table . The chemisorbent TEPA-SBA-15 exhibits far superior DAC performance when compared to each of the physisorbents, adsorbing the most CO2 and the least H2O after 12h of exposure