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Dermal delivery system has the characteristics of painlessness, low first-pass effect, and high patient compliance, making it a good supplementary form for oral and injection preparations. However, some obvious shortcomings, such as difficulty in storing drugs or poor control of drug release, hinder the development of transdermal delivery systems. The inherent specific binding properties of MIPs to template drug molecules result in their relatively high drug loading and controllable release properties, making them a functional excipient for the research and development of new transdermal delivery formulations. In this chapter, we reviewed in detail the latest research status of all MIPs-based transdermal preparations, including the synthesis of MIPs particles or membranes, the assembly of transdermal patches, and the evaluation of drug release performance. Their shortcomings and future development directions were also described.

Imprinted monoliths are highly selective and cost-effective materials, which have attracted significant interest in various areas, mostly as the stationary phase used in high performance liquid chromatography (HPLC) and capillary electrochromatography (CEC). This review focuses on the recent significant progress of the imprinted monoliths in preparations and applications. Some thoughts on perspectives of imprinted monoliths are also expressed.

One of the major drawbacks of conventional molecularly imprinted polymers (MIPs) is the requirements of volatility porogenic solvent during polymerization. To overcome the default, MIP based on deep eutectic solvent (DES, a new type of green designer solvents) has been synthesized successfully. To improve the affinity of the MIP based on DES, in this work, a strategy of metallic pivot was suggested in the first time to prepare a highly selective MIP monolithic column. A cetirizine-imprinted polymer was prepared in a DES-based porogen system composed of choline chloride/ ethylene glycol (ChCl-EG) in the presence of Co(Ac)2 as metallic pivot. The resulting DES- Co2+-MIP monolith had 23.5 times higher imprinting factor than the Co2+-free MIP monolith. The characterization of polymers indicated that DES was one of the primary factor influencing the MIP morphology and pore structure. Compared with previous metal-mediated and ionic liquid-based imprinted polymers, the introduction of DES as a porogen in polymerization led to higher imprinting factor (approximately 2.9 - 17.1 times). In addition, the resulting DES-Co2+-MIP can be used as an adsorbent for extraction of cetirizine from ethanol solution with the recoveries of 97.8%. As a conclusion, the metallic pivot is a rather valuable strategy for the synthesis of DES-based MIP monolith with high selectivity.

A core-shell organic-inorganic hybrid molecularly imprinted polymer (MIP) based on metal-organic framework 177 (MOF-177) was designed and synthesized. In the polymerization system, S-amlodipine (S-AML) was used as template, methacrylic acid as functional monomer, tetraethoxysilane as crosslinker, MOF-177 as core support material and acetic acid as catalyst. The influences of the ratio of S-AML to methacrylic acid, the content of the crosslinker, the concentration of the catalyst, polymerization time as well as ultrasonic process on the affinity of the MOF-177@MIPs were investigated. The experiments of static adsorption equilibrium demonstrated that the MOF-177@MIPs had higher adsorption capacity (Qmax = 1.31 mmol g−1) than that of the non-imprinted polymers (MOF-177@NIPs, Qmax = 0.23 mmol g−1) with maximum imprinting factor (IF) of 5.79. The faster binding kinetics and transfer-mass speed were obtained on the MOF-177@MIPs than on traditional non-core-shell MIPs. These studies suggested that using MOF-177 as core to prepare MIPs is a powerful approach to core-shell organic-inorganic hybrid MIPs with higher affinity and selectivity.

This review focused on the developments in the field of molecularly imprinted polymers (MIPs) for CEC since 2009. New preparation techniques of MIP-based CEC, such as, portable microchip with macroporous monolithic imprinted microchannel, and low cross-linking MIPs based on liquid crystalline monomers, were discussed. Using selected cases rather than a comprehensive review of the entire field, our goal is to highlight the studies of the interest with an emphasis on recent work, and offers suggestions for future development in the field of imprinted materials for CEC separation.

A kind of chiral azobenzene was synthesized. The formation of chiral azobenzene was confirmed by IR and1H NMR spectroscopy, and mesomorphic properties were investigated by DSC and POM. The reversible optically induced switching effect betweentransandcisisomer of chiral azobenzene was demonstrated by a UV/Vis/NIR spectrophotometer. It was found that cholesteric liquid crystal molecular alignment could be adjusted by these chiral azobenzene.

In this paper, a molecularly imprinted polymer (MIP) coating grafted to a trimethylolpropane trimethacrylate (TRIM) core material for CEC was reported. The core monolith was prepared with a solution of 20% (w/w) TRIM in a mixture of porogen and a polymerization precursor, which can generate a stable electroosmotic flow due to the formation of ionizable groups after postpolymerization hydrolization. Graft polymerization took place on the resultant TRIM monolith with a mixture of template, methacrylic acid, and ethylene glycol dimethacrylate. Strong recognition ability (selectivity factor was 5.83) for S-amlodipine and resolution of enatiomers separation (up to 7.99) were obtained on the resulting grafted imprinted monolith in CEC mode. The influence of CEC conditions on chiral separation, including the composition of mobile phase, pH value, and the operating voltages was studied. These results suggest that the method of grafted polymerization reported here allows a rapid development of MIP monolith once core materials with desired properties are available, and is a good alternative to prepare CEC-based monolithic MIPs.

Molecular crowding is a new approach to promoting molecular imprinting more efficiently. In this work, this concept was applied to the preparation of low cross-linked imprinted polymers in the presence of an immobilised template for stabilizing binding sites and improving molecular recognition. An imprinted monolithic column was synthesized using a mixture of 2,4-diamino-6-methyl-1,3,5-triazine (template), 2,4-diamino-6-(methacryloyloxy) ethyl-1,3,5-triazine (polymerisable template), methacrylic acid, ethylene glycol dimethacrylate, and polystyrene (molecular crowding agent). Some polymerization factors, such as template-monomer molar ratio, the composition of the porogen and crosslinking density, on the imprinting effect of resulting MIP monolith were systematically investigated. The results indicated that the imprinted monolithic columns prepared in the presence of molecular crowding agent retained affinity and specificity for template even when prepared with a level of cross-linker as low as 9%. Moreover, a stoichiometric displacement model for retention was successfully applied to evaluate the interaction between the solute and the stationary phase. Compared with the low cross-linked MIP prepared by conventional polymerization, the molecular crowding-based low cross-linked monolithic MIPs showed higher selectivity. The results suggested that molecular crowding is a powerful strategy to increase the effect of molecular imprinting at a low level of crosslinker.

This review focused on the developments in the field of molecularly imprinted polymers (MIPs) for CEC since 2009. New preparation techniques of MIP-based CEC, such as, portable microchip with macroporous monolithic imprinted microchannel, and low cross-linking MIPs based on liquid crystalline monomers, were discussed. Using selected cases rather than a comprehensive review of the entire field, our goal is to highlight the studies of the interest with an emphasis on recent work, and offers suggestions for future development in the field of imprinted materials for CEC separation.

In this paper, a molecularly imprinted polymer (MIP) coating grafted to a trimethylolpropane trimethacrylate (TRIM) core material for CEC was reported. The core monolith was prepared with a solution of 20% (w/w) TRIM in a mixture of porogen and a polymerization precursor, which can generate a stable electroosmotic flow due to the formation of ionizable groups after postpolymerization hydrolization. Graft polymerization took place on the resultant TRIM monolith with a mixture of template, methacrylic acid, and ethylene glycol dimethacrylate. Strong recognition ability (selectivity factor was 5.83) for S-amlodipine and resolution of enatiomers separation (up to 7.99) were obtained on the resulting grafted imprinted monolith in CEC mode. The influence of CEC conditions on chiral separation, including the composition of mobile phase, pH value, and the operating voltages was studied. These results suggest that the method of grafted polymerization reported here allows a rapid development of MIP monolith once core materials with desired properties are available, and is a good alternative to prepare CEC-based monolithic MIPs.

Low loading capacity is the main problem of molecularly imprinted stationary phase, which is attributed to the high level of crosslinking restricting distortion phenomena of polymer backbone in molecular imprinting. A new approach based on liquid crystal with recognition ability is demonstrated for synthesis of molecularly imprinted polymer coatings in a low level of crosslinking. The resulting low crosslinking (20%) open-tubular imprinted capillary was able to separate enantiomers by means of capillary electrochromatography. The resolution of enantiomer separation achieved on the (S)-amlodipine-imprinted capillary was up to 6.36 in less than 2.5 min. The strong recognition ability with a selectivity factor of 1.81 and high column performance of template (up to 23,300 plates/m) were obtained. Performance of imprinting comparable to that recorded in conventional MIP stationary phase was observed. The liquid crystal MIP coatings were also prepared using either (S)-naproxen or (S)-ofloxacin as template molecule. The resolutions of enantiomers separation were 1.41 and 1.55, respectively. The results illustrate that the synthesis of low crosslinking MIP coatings based on liquid crystal is not only an experimental-simplified process of high performance, but also an approach to produce chiral stationary phase comparable to other chiral stationary phases.

To the authors' knowledge, few studies have been conducted to date regarding dietary selenium and the potential gene-nutrient interactions with single-nucleotide polymorphisms (SNPs) in different pathways on the risk of esophageal cancer.The authors investigated the role of dietary selenium intake and its interplay with SNPs of the ALDH2 (glutamic acid [Glu] 487 lysine [Lys]) and the X-ray repair cross-complementing 1 (XRCC1) (arginine [Arg] 399 glutamine [Gln]) genes on the risk of esophageal squamous cell carcinoma (ESCC) in a population-based, case-control study in China. In total, 218 patients with ESCC and 415 healthy population control participants were interviewed. Dietary selenium intake was estimated from a food frequency questionnaire with 97 food items. ALDH2 and XRCC1 polymorphisms were detected with a polymerase chain reaction-restriction fragment length polymorphism assay.The adjusted odds ratio (OR) for the highest quintile of dietary selenium intake, compared with the lowest quintile of intake, was 0.48 (95% confidence interval [95% CI], 0.25-0.89), with a strong dose-response relation (P for trend,.01). The ALDH2 Lys and XRCC1 Gln variant alleles were associated with an increased risk of ESCC with adjusted ORs of 1.91 (95% CI, 0.96-3.80) and 1.67 (95% CI, 1.08-2.59), respectively. An elevation of the risk for ESCC was pronounced most among carriers of ALDH2 Lys/Lys and XRCC1 399Gln/Gln or Gln/Arg who consumed a low level of dietary selenium (adjusted OR, 4.16; 95% CI, 1.14-15.12).To the authors' knowledge, this is the first in-depth study to suggest that genetic susceptibility may modify the association between selenium intake and the risk of ESCC. The findings indicated that individuals with low dietary selenium intake and ALDH2 Lys/Lys and XRCC1 399Gln/Gln or Gln/Arg genotypes were associated with an increased ESCC risk, especially in the presence of exposure to tobacco and alcohol carcinogens.

To study the relationship between ambient air pollution and daily mortality of SARS in Beijing.The approach of time-series Poisson regression was used to assess the relationship between daily SARS mortality, ambient air pollution, and other factors from April 25 to May 31, 2003 in Beijing.An increase of each 10 microg/m3 over a 5-day moving average of PM10, SO2 and NO2 corresponded to 1.06 (1.00-1.12), 0.74 (0.48-1.13) and 1.22 (1.01-1.48) relative risks (RRs) of daily SARS mortality, respectively. The relative risks (RRs) values depended largely on the selection of lag days.The daily mortality of SARS might be associated with certain air pollutants in Beijing.

To explore the relationship between methyl-tetra-hydrofolic acid (MTHFR) 677 gene polymorphism and the risk of stomach cancer.A population based case-control study was conducted and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to detect its genotypes.Among cases with stomach cancer, the frequency of C/C, C/T, T/T genotype were 25.8%, 54.6%, 19.6%, compared with controls as 34.5%, 50.9%, 14.6% respectively. Using C/C genotype as reference, the OR of C/T or T/T genotype was 1.52 (95% CI: 1.04 - 2.23). 53.3% C and 46.7% T allele were distributed in stomach cancer cases, while 60.0% C and 40.0% T in controls. The OR for T allele in relation to C allele was 1.31 (1.02 - 1.69) when C allele was used as reference. In addition, the present study showed that MTHFR677 AnyT genotype might interact with smoking, moldy food intake, wheat porridge intake, eating salty food and Hp CagA infection to increase the risk of stomach cancer. No interaction was observed between MTHFR677 AnyT genotype and alcohol drinking or green tea intake.MTHFR677 AnyT genotype, might increase the risk of stomach cancer development and the genotype might also interact with other environmental risk factors to increase the risk of stomach cancer.

To assess the protective effect of drinking green tea on the development of gastric, liver and esophageal cancers.A population based study was conducted in Taixing, Jiangsu province, including 206, 204, 218 cases, respectively, and 415 population controls.Green tea decreased the development of gastric cancer risk by 40%. Dose-response relationships were observed between the length of time, concentration and quantity of green tea drinking and its protective effects on gastric cancer. For individuals who drink green tea for more than 250 g per month, the risk of gastric cancer reduced about 60%. Green tea might have protective effect on liver cancer. However, no protective effect of green tea was observed on esophageal cancer.Green tea drinking might be a protective factor for gastric cancer. However, the protective effects of green tea on liver and esophageal cancer were not obvious.

To explore the role of green tea in decreasing the risks of gastric cancer, liver cancer, esophageal cancer among alcohol drinkers or cigarette smokers.A population based case-control study was conducted in Taixing, Jiangsu province.In Taixing city, identified cases of stomach, liver and esophageal cancers were chosen with informed consent. The numbers were 206, 204, 218 respectively. Controls were chosen from normal population having lived in the area for longer than 10 years, also with informed consent. Green tea drinking seemed to have decreased 81%, 78%, 39% risk for the development of gastric cancer, liver cancer and esophageal cancer among alcohol drinkers. It might also have decreased 16%, 43%, 31% on the risks of developing the three kinds of cancers among cigarette smokers. Interaction assessment showed that drinking green tea could significantly decrease the risk of gastric cancer and liver cancer among alcohol drinkers, with ORs of interaction item 0.23 (95% CI: 0.10 - 0.55) and 0.25 (95% CI: 0.11 - 0.57) respectively.Habit of drinking green tea seemed to have significant protective effects on the development of both gastric and liver cancer among alcohol drinkers while, green tea also having some protective effect on esophageal cancer among alcohol drinkers and on three kinds of cancers among cigarette smokers.