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The formation of inclusion complexes between triamterene (TT) and cyclodextrins (CDs) to increase the water apparent solubility of TT was investigated. UV data showed that the binding constant of the TT/sulfobutylether-β-cyclodextrin (SBE-β-CD) inclusion complex was 510 L/mol. The phenyl ring of TT was inserted into the secondary hydroxy face of SBE-β-CD, as demonstrated by

Lipid emulsions are potential carriers for poorly water-soluble drugs. Previously, we revealed that lipid nanoparticles complexed with styrene maleic acid copolymer (SMA) disintegrate under acidic pH. In the present study, SMA-containing lipid emulsions (SMA emulsions) were prepared and their physicochemical and biological properties were examined to test whether SMA emulsions could be used as a trigger to facilitate drug release in response to pH reduction. By sonicating lipid and SMA mixtures, homogeneously sized SMA emulsion particles were prepared as verified via dynamic light scattering and transmission electron microscopy. Upon the reduction of solution pH, disintegration of SMA emulsions was observed, which may be utilized for drug release at mildly acidic pH. In addition, the sensitivity to pH changes could be controlled by altering the lipid composition. Serum proteins bound to SMA emulsions were analyzed to predict the metabolic fate upon intravenous injection. Predictably, apolipoproteins were abundantly bound, suggesting that SMA emulsions should avoid being recognized as foreign substances. Furthermore, subcellular distribution studies using a human breast cancer cell line (MDA-MB-231) demonstrated that SMA emulsions localize to lysosomes, which have a lower pH. These results suggest that SMA emulsions could be promising pH-responsive drug carriers.

Little is known about the pharmacokinetics of phenobarbital in terminally ill cancer patients. We investigated whether phenobarbital clearance alters depending on the length of survival. We retrospectively reviewed the clinical, laboratory, and therapeutic drug monitoring (TDM) records of patients who received parenteral or oral phenobarbital for 21 consecutive days or longer between 2000 and 2016. Patients were divided into non-cancer and cancer groups. Cancer patients were further stratified according to the survival interval after TDM: those who survived > 3 months were classified as long-surviving and the remainders short-surviving cancer patients. Phenobarbital clearance (CLPB) was calculated at steady state. Multiple comparisons of median CLPB were conducted among the three groups. Data were collected from 44 non-cancer patients and 34 cancer patients comprising 24 long-surviving and 10 short-surviving cancer patients. Among 10 short-surviving cancer patients, 4 had hepatic metastasis. Median CLPB (range) in short-surviving cancer patients [0.076 (0.057‒0.114) L/kg/day] was significantly (p

The formation of inclusion complexes between S-(−)-equol (SEq) and cyclodextrins (CDs) was investigated. The binding constant (Kc) of the SEq/sulfobutylether-β-cyclodextrin (SBE-β-CD) inclusion complex was determined to be 1600 L/mol based on UV data. The phenyl ring of the SEq molecule was found to be inserted from the secondary hydroxyl face of the SBE-β-CD as evidenced from 1H–1H rotating frame nuclear Overhauser effect spectroscopy (ROESY) NMR. The thermal properties of the solid SEq/SBE-β-CD inclusion complexes prepared by physical mixing, kneading and freeze-drying methods were studied by differential scanning calorimetry. For the solid complex obtained by the freeze-drying method, the endothermic peak corresponding to the melting point of SEq disappeared. The solid SEq/SBE-β-CD complexes exhibited a high score in antioxidant activity evaluation tests compared to SEq alone. Dissolution test revealed that the solid complex obtained by freeze-drying method had improved dissolution of SEq.

The effect of cancer cachexia on the pharmacokinetics of vancomycin remains unclear. We investigated whether the pharmacokinetics of vancomycin and the risk of kidney injury are altered with the development of cancer cachexia. A retrospective analysis was conducted using therapeutic drug monitoring data obtained from 86 cancer patients who received vancomycin intravenously for infection. The patients were classified into four groups according to the stage of cachexia defined by international consensus—non-cachexia (n = 26), pre-cachexia (n = 10), cachexia (n = 21) and refractory cachexia (n = 29). Vancomycin pharmacokinetics were analyzed by a traditional one-compartment model and Bayesian method using plasma concentrations measured in these patients. Renal function and pharmacokinetic parameters were compared between the non-cachexia patients (n = 26) and total cancer cachexia patients (n = 60). No significant difference in estimated glomerular filtration rate was observed between the non-cachexia and the total cancer cachexia patients. In contrast, systemic clearance of vancomycin was significantly lower in the total cancer cachexia patients compared with the non-cachexia patients when analyzed by the traditional one-compartment model [median (range)—49.7 (9.8‒98.7) vs 70.2 (12.5‒211.8) mL/min, p

BACKGROUND The influence of cancer cachexia on the pharmacokinetics of and kidney injury caused by amikacin remains unclear. This study investigated whether the pharmacokinetics of amikacin and the risk of kidney injury are altered with the progression of cancer cachexia. METHODS A retrospective analysis was conducted using therapeutic drug monitoring data obtained from 52 cancer patients who received amikacin intravenously for infection(s). The patients were classified into 2 groups based on the status of cachexia using a consensus definition: noncachexia group (n = 31) and cachexia group (n = 21). Differences in amikacin pharmacokinetics and occurrence of kidney injury were compared between the 2 groups. Amikacin pharmacokinetics was calculated based on a 1-compartment model using peak and trough concentrations measured clinically for therapeutic drug monitoring. In addition, intrapatient analysis was conducted based on patients who received amikacin treatments more than once during the study period to examine the alteration in amikacin pharmacokinetics with the progression of cancer cachexia. RESULTS Systemic clearance of amikacin [median (range)] was significantly (P < 0.05) lower in the cachexia group [37.3 (11.2-87.3) (mL/min)] than in the noncachexia group [52.0 (19.1-133.4) (mL/min)]. In contrast, volume of distribution was significantly (P < 0.05) increased in the cachexia group [0.47 (0.20-1.45) L/kg] compared with the noncachexia group [0.32 (0.21-1.00) L/kg]. There was no difference in the occurrence of kidney injuries between the 2 groups. In an intrapatient analysis of the longitudinal alteration of amikacin pharmacokinetics, an approximately 50% reduction in clearance and 30% increase in volume of distribution were observed as cancer cachexia progressed. CONCLUSIONS The present study suggests that progression of cancer cachexia may reduce amikacin clearance and increase the volume of distribution, but cancer cachexia does not increase amikacin-induced kidney injury.

The formation of inclusion complexes between betahistine (BTH) and the β-CD derivatives were investigated. The binding constant (K c ) of the BTH/β-cyclodextrin (β-CD) inclusion complex was determined to be 1400 L/mol based on UV data. The structure of the BTH/β-CD complex in aqueous solution was examined by 1H–1H rotating frame nuclear Overhauser effect spectroscopy (ROESY) NMR, and the pyridine ring and side chain moiety of the BTH molecule were found to be inserted from the secondary hydroxyl face of the β-CD. The thermal properties of the solid BTH/β-CD inclusion complexes prepared by kneading and freeze-drying methods were studied by differential scanning calorimetry, and for comparison, solid betahistine mesilate (BTHm)/β-CD inclusion complexes were similarly prepared. Humidity tests showed that the solid BTH/β-CD complexes exhibited less moisture absorption compared to the BTHm alone and BTHm/β-CD complexes.

Eculizumab given bi-weekly is widely recommended for the treatment of paroxysmal nocturnal hemoglobinuria (PNH). We undertook a retrospective analysis on the medical records of 763 dosings of 14 PNH patients to investigate whether a threshold would exist in dosing intervals associated with breakthrough hemolysis. We identified 12 events of breakthrough hemolysis in 4 patients. Multivariate logistic regression and receiver operating characteristics (ROC) analysis revealed a significant association between increased risk of breakthrough hemolysis and prolonged dosing intervals of 17 days or more and concomitant inflammation: odds ratios (OR) and 95% confidence intervals (CIs) were 1.6 (1.3-2.0, p

In this work, the intercalation of alkyl trimethylammonium ion (CnN+) and dialkyl dimethylammonium ion (2CnN+) were attempted for α‑zirconium phosphate (α-ZrP) and γ-ZrP. And then a pure intercalation compounds were obtained only for γ-ZrP. It was expected that the intercalation of linear quaternary ammonium ion would produce not only a hydrophobic environment in the interlayer space but also form an appropriate void for the adsorption of hydrophobic air pollutants. The basal spacing of 2CnN+-intercalated γ-ZrP was greater than that of CnN+-intercalated γ-ZrP because CnN+ was arranged in a mono-molecular structure in the interlayer space contrary to the bi-molecular structure of 2CnN+. Furthermore, the alkyl chain in the interlayer space of γ-ZrP was in a gauche form for CnN+, for a smaller carbon number (n), and changed to a trans structure for a larger n. γ-ZrP with a modified interlayer space could adsorb gaseous aromatic hydrocarbons contrary to the nonmodified γ-ZrP. Maximum adsorption was attained for C18N+-intercalated γ-ZrP with a mono-molecular structure and trans structure alkyl chain, although the basal spacing and uptake of alkyl ammonium reached a maximum for 2C18N+-intercalated γ-ZrP. Hence, not only the basal spacing and carbon number but also the void space in the interlayer region affected adsorption. It was interesting to note that the conformation of the long alkyl chain was reversibly changed through adsorption and desorption.

Layered double hydroxides (LDHs) have been used commercially as antacids, to stabilize drugs, to allow the controlled release of incorporated drugs, and to act as drug carriers to reduce drug accumulation within the body. Several types of LDH were investigated: nitrate type (LDH-NO3); chloride type (LDH-Cl); and carbonate type (LDH-CO3). Each type was added to an aqueous or methanol (MeOH) solution containing a drug (pravastatin or nateglinide). With pravastatin sodium, the interlayer distance expanded after reaction with LDH-NO3 and LDH-Cl in aqueous solution. In contrast, the interlayer distance of LDH-CO3 increased in methanol with nateglinide. Each drug was intercalated into the interlayer space of LDH by ion exchange. The hygroscopicity of the drug substances, complexes, and physical mixtures were determined at 70% relative humidity. Increases in weight (%) of the complexes were less than those of the physical mixtures, which demonstrates that hygroscopicity was reduced upon complexation with LDH due to the layer of LDH over the drugs.

The immobilization of potassium sorbate, potassium aspartate and sorbic acid in layered double hydroxide under solid condition was examined. By simply mixing two solids, immobilization of sorbate and aspartate in the interlayer space of nitrate-type layered double hydroxide, so called intercalation reaction, was achieved, and the uptakes, that is, the amount of immobilized salts and the interlayer distances of intercalation compounds were almost the same as those obtained in aqueous solution. However, no intercalation was achieved for sorbic acid. Although intercalation of sorbate and aspartate into chloride-type layered double hydroxide was possible, the uptakes for these intercalation compounds were lower than those obtained using nitrate-type layered double hydroxide. The intercalation under solid condition could be achieved to the same extent as for ion-exchange reaction in aqueous solution, and the reactivity was similar to that observed in aqueous solution. This method will enable the encapsulation of acidic drug in layered double hydroxide as nano level simply by mixing both solids.

Etodolac (2-[(1RS)-1,8-diethyl-1,3,4,9-tetrahydropyrano[3,4-b]indol-1-yl]acetic acid) is a nonsteroidal anti-inflammatory drug (NSAID) with a bitter taste. It is slightly soluble in water. Hydrotal...

Non-steroidal anti-inflammatory drugs (NSAIDs)-induced small intestinal injury is a serious clinical event with recent advances of diagnostic technologies, but a successful therapeutic method to treat such injuries is still lacking. Licorice, a traditional herbal medicine, and its derivatives have been widely used for the treatment of a variety of diseases due to their extensive biological actions. However, it is unknown whether these derivatives have an effect on NSAIDs-induced small intestinal damage. Previously, the anti-inflammatory effects of three compounds extracted from the licorice root, glycyrrhizin, 18β-glycyrrhetinic acid, and dipotassium glycyrrhizinate, were compared in vitro cell culture. The most prominent inhibitory effect on the tumor necrosis factor-α (TNF-α) production was observed with the administration of 18β-glycyrrhetinic acid as an active metabolite of glycyrrhizin. In this study, a complex compound of 18β-glycyrrhetinic acid and hydroxypropyl γcyclodextrin was examined to improve the oral bioavailability. After administration of this complex to indomethacin treated mice, a significantly high plasma concentration of 18β-glycyrrhetinic acid was detected using the tandem mass spectrometry coupled with the HPLC. Furthermore, the complex form of 18β-glycyrrhetinic acid and hydroxypropyl γcyclodextrin reduced mRNA expressions of TNF-α, interleukin (IL)-1β, and IL-6, which was histologically confirmed in the improvement of indomethacin-induced small intestinal damage. These results suggest that the complex of 18β-glycyrrhetinic acid and hydroxypropyl γcyclodextrin has the potential therapeutic value for preventing the adverse effects of indomethacin-induced small intestinal injury.

The solubility of melatonin (MT) was improved with the addition of modified cyclodextrins (CDs). The solubilities of MT in the presence of β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (HP-β-CD), mono-6-O-maltosyl-β-cyclodextrin (mono-G2-β-CD), methyl-β-cyclodextrin (Me-β-CD), and sulfobutylether-β-cyclodextrin (SBE-β-CD) were higher than that of MT itself. In particular, the solubility of MT in the presence of SBE-β-CD was 11 times higher than that of MT itself. The stability constant (K) obtained based on the fluorescence intensity was 490 L/mol for the MT/SBE-β-CD inclusion complex. The structure of the MT/SBE-β-CD complex in aqueous solution was examined by 1H–1H rotating frame nuclear overhauser effect spectroscopy NMR. A 5-methoxy moiety of MT was included from the secondary hydroxyl face of SBE-β-CD. The MT/SBE-β-CD inclusion complex was prepared by the freeze-drying method. The results of X-ray diffraction and differential scanning calorimetry confirmed the formation of the complex in solid.

The phosphorylation of 5'-deoxy-5-fluorouridine (doxifluridine, 5'-DFUR) has been achieved using inorganic cyclo-triphosphate (P(3m), Na(3)P(3)O(9)) and monoimido-cyclo-triphosphate (MCTP, Na(3)P(3)O(8)NH) in aqueous solution. In the reaction of 5'-DFUR with P(3m), 2'-monophospho-5'-DFUR and 3'-monophospho-5'-DFUR were synthesized with a total yield of more than 95%. In the reaction of 5'-DFUR with MCTP, 2'-diphosphoramidophosphono-5'-DFUR and 3'-diphosphoramidophosphono-5'-DFUR were synthesized with a total yield of more than 40%. The phosphorylated products with P(3m) and MCTP were stable in neutral and alkaline solutions.

Phosphonylation of 3',4'-dihydroxy-L-phenylalanine (L-DOPA) has been achieved using inorganic diphosphonate (DP) in aqueous solution. The optimum condition for the phosphonylation of L-DOPA with DP is L-DOPA : DP = 1 : 10, pH 6 and 25 oC. 3'-Hydroxy-4'-phosphonyl-L-phenylalanine and 3'-phosphonyl-4'-hydroxy-L-phenylalanine were synthesized with the total yield of more than 62%. The phosphonylated products of L-DOPA were stable in neutral and acidic solution. The reaction mechanism of L-DOPA with DP was discussed.

The solubility of α-lipoic acid (LA) with the addition of modified cyclodextrins was investigated using the solubility method. The solubility of LA in the presence of β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (HP-β-CD), mono-6-O-glucopyranosyl-β-cyclodextrin (mono-G1-β-CD), methyl-β-cyclodextrin (Me-β-CD), 2,6-di-O-methyl-β-cyclodextrin (DM-β-CD), and sulfobutylether-β-cyclodextrin (SBE-β-CD) was higher than that of LA itself. In particular, the solubility of LA in the presence of SBE-β-CD was 20 times higher than that of LA alone. The structure of the inclusion complex of SBE-β-CD and LA in aqueous solution was examined by 1H-1H ROESY NMR spectroscopy. The 1,2-dithiolane moiety of LA was included from the secondary hydroxyl face of SBE-β-CD. The solid complexes of LA and SBE-β-CD were prepared by the kneading and freeze-drying methods. Formation of the solid complexes was confirmed by X-ray diffraction patterns (XRD), differential scanning calorimetry (DSC), and infrared spectroscopy (IR). The kneading and freeze-drying methods were successful for obtaining the solid inclusion complexes with improved thermal stability.

Phosphorylation of cytarabine has been achieved using inorganic cyclo—triphosphate (P3m) in aqueous solution. The optimum condition for the phosphorylation of cytarabine with P3m is cytarabine : P3m = 1 : 10, pH 12 and 25 °C. Cytarabine 5′–triphosphate, cytarabine 3′–triphosphate, and cytarabine 2′–triphosphate were synthesized with the total yield of more than 75%. The phosphorylated products of cytarabine were stable in neutral and alkaline solution. The reaction mechanism of cytarabine with P3m was discussed.

The intercalations of melamine into α- and γ-zirconium phosphates (α- and γ-ZrP) were investigated. Melamine-intercalated α-ZrP afforded two phases with different interlayer distances ( d = 1.30 and 1.55 nm). The phase with d = 1.30 nm was obtained as the mixture with original α-ZrP at 30 min reaction by batch method, whereas the single phase with d = 1.55 nm was obtained by decantation method in saturated melamine aqueous solution. Contrary to this, for γ-ZrP a phase with d = 1.78 nm was obtained by both batch and decantation methods in saturated melamine aqueous solution. And new phase with d = 1.48 nm was formed in batch method at low pH or lower concentration of melamine aqueous solution. In these phases the arrangement of melamine changed from a monolayer structure to a bilayer structure with the increase of interlayer distance. Furthermore, melamine-intercalated α- and γ-ZrP adsorbed formaldehyde gas and formaldehyde in formalin solution by interacting with melamine molecule in the interlayer region. In melamine-intercalated γ-ZrP with d = 1.48 nm, the expansion of interlayer distance to around 1.6 nm was observed after the adsorption of formaldehyde gas and formaldehyde in formalin solution. The adsorption of formaldehyde in formalin solution was accompanied with the release of melamine in the interlayer region with increasing the concentration of formaldehyde at 65 °C.

Phosphorylation of polyamidoamine dendrimers has been achieved using inorganic cyclo-triphosphate in aqueous solution. In the phosphorylation of polyamidoamine dendrimers, triphosphate derivatives of them were synthesized with the yields of more than 95%. For polyamidoamine dendrimer with four terminal amino groups, two phosphorylated products were obtained.

The intercalation of sulfobutyl ether β-cyclodextrin (SBE7-β-CD) into Mg–Al-layered double hydroxide (abbreviated as LDH) known as hydrotalcite was examined aiming for the controlled release of drugs. Complete intercalation of SBE7-β-CD was attained using LDH(NO3) with Mg/Al ratio of 2. The intercalation compound showed the interlayer distance of 2.15 nm. Above 1 mM of SBE7-β-CD aqueous solution, the intercalation compound with different uptake amount of SBE7-β-CD was obtained as a single phase. The inclusion of prazosin could be attained by two methods, that is, the inclusion by SBE7-β-CD-intercalated LDH and the intercalation of prazosin-included SBE7-β-CD in LDH(NO3). And the sustained release of prazosin was attained successfully by regulating the uptake of SBE7-β-CD.

Porous zirconium phosphate was prepared by silylation with organic silanes. Octylamine was intercalated into α-Zr(HPO 4 ) 2 ·H 2 O for expanding interlayer spacing and 1,2-bis(dimethylchlorosilyl)ethane (BMCE) was used for silylation of inorganic layers in toluene. The number of octhylamine molecules intercalated was similar to the number of phosphorus in the inorganic layers. On the other hand, that of BMCE molecule after silylating treatment was much smaller than that of phosphorus. The interlayer spacing of silylated compound was confirmed to expand via high-temperature XRD patterns and was preserved on thermal treatment up to around 500 °C. The maximum specific surface area of the silylated compound heated at 300 °C was around 70 m 2 /g, though that was smaller for silylated compounds heated at higher and lower temperature.

The biogenic amines (dopamine, serotonin, noradrenaline, and adrenaline) were intercalated into layered zirconium phosphates (ZrP). The intercalation reaction into α-ZrP depended on pH of their aqueous solutions. On the other hand, for γ-ZrP the uptake of dopamine and serotonin increased with the increase of their concentration, where as that of noradrenaline and adrenaline depended on pH. Their intercalation compounds were microscopically investigated by solid-state NMR.

Intercalations of mercaptocarboxylic acid and dithiodicarboxylic acid in Mg–Al layered double hydroxide and their adsorption properties for heavy metal ions were examined. During the intercalation of mercaptocarboxylic acids, mercapto group was oxidized, and the corresponding dithiodicarboxylic acids were intercalated in the interlayer space of Mg–Al layered double hydroxide. The intercalation compounds adsorbed mercury and sliver ions effectively, whereas there was no adsorption of copper ion practically.

The intercalation of l -ascorbic acid (ASA) into three kinds of layered double hydroxides, such as Mg–Al, Mg–Fe and Zn–Al LDHs, has quantitatively been investigated by the calcination-rehydration (reconstruction) and coprecipitation methods. The amount of ASA intercalated was considerably different by the LDH systems that was estimated to be ca. 0.40 mol/mol-M3+ for the Mg–Al and Mg–Fe systems by the reconstruction method. The Zn–Al system was hardly restored to the LDH structure by the rehydration reaction with the intercalation of ASA. ASA was also intercalated into the Mg–Al and Zn–Al LDHs by the coprecipitation method, while the intercalation of NO3− was observed in the Mg–Fe LDH. The basal spacing of the solid products were expanded to d003 = 0.84 (Mg–Al) and 0.86 (Mg–Fe) nm by the reconstruction method, 0.97 (Mg–Al) and 1.06 (Zn–Al) nm by the coprecipitation method, respectively, suggesting that ASA was intercalated into the LDHs. A large fraction of ASA was intercalated as reduced form after the light and heat resistance tests of the ASA/LDHs. This result confirmed that ASA was stabilized by the intercalation of the LDHs interlayer space. Furthermore, the intercalated ASA was easily deintercalated from the LDH interlayer space by the ion exchange method using CO32−. It is expected that LDHs will be good host materials for safe storage of vitamins.

Phosphorylation of D-glucose has been achieved using inorganic diimido-cyclo-triphosphate in aqueous solution. In the phosphorylation of D-glucose and maltose, 1-O-diimidotriphospho-β-D-glucose and 1-O-diimidotriphospho-β-maltose were stereoselectively synthesized with yields of 35 and 30 %, respectively. For α-cyclodextrin, γ-cyclodextrin, and mono-6-O-α-maltosyl-β-cyclodextrin, two phosphorylated products were obtained in each cyclodextrin and main products were mono-2-O-diimidotriphosphoryl esters of cyclodextrin.

The addition of urea was studied as one of the preparation methods for porous phosphate particles. Urea was added to the preparation of lanthanum pyrophosphate from lanthanum nitrate and sodium pyrophosphate solutions. The precipitations prepared in various concentration of urea and their thermal products were estimated about the chemical composition, powder and acidic properties. The addition of urea on preparation of lanthanum pyrophosphate produced the increase of about 10-20 nm-radius pores. The large amount of urea covered the pore of lanthanum pyrophosphate. The amount of included urea in lanthanum phosphate was estimated from NH3-TPD curves. The addition of urea did not improve the adsorption ratio of trimethylamine because of the balance between the remained urea and improvement of specific surface area.

The immobilization of potassium sorbate, potassium aspartate and sorbic acid in layered double hydroxide under solid condition was examined. By simply mixing two solids, immobilization of sorbate and aspartate in the interlayer space of nitrate-type layered double hydroxide, so called intercalation reaction, was achieved, and the uptakes, that is, the amount of immobilized salts and the interlayer distances of intercalation compounds were almost the same as those obtained in aqueous solution. However, no intercalation was achieved for sorbic acid. Although intercalation of sorbate and aspartate into chloride-type layered double hydroxide was possible, the uptakes for these intercalation compounds were lower than those obtained using nitrate-type layered double hydroxide. The intercalation under solid condition could be achieved to the same extent as for ion-exchange reaction in aqueous solution, and the reactivity was similar to that observed in aqueous solution. This method will enable the encapsulation of acidic drug in layered double hydroxide as nano level simply by mixing both solids.

The coprecipitation of amino acids and oligopeptides with the Zn–Al LDH was investigated using phenylalanine (Phe), phenylalanyl-phenylalanine (Phe-Phe), glycyl-phenylalanine (Gly–Phe), glycine (Gly), glycyl-glycine (Gly–Gly), glycyl-glycyl-glycine (Gly–Gly–Gly) and N-(N-γ-glutamyl-cysteinyl)-glycine (GSH) as guest species. The coprecipitation behavior of amino acids and oligopeptides was found to be influenced by the solution pH and the kind of their side chain groups, and reached the maximum at pH 8 or 9. The basal spacing, d003, of the Phe, Phe-Phe and GSH/LDH was 1.81, 2.41 and 1.64 nm, supporting that guests were arranged vertical to the LDH basal layer. Acceding to the basal spacing of the Gly, Gly–Gly and Gly–Gly–Gly/LDH (d003=0.84–0.88 nm), these guests were oriented horizontal to the LDH basal layer with the co-intercalated NO 3 − . Moreover, the amount of Phe-Phe, Gly–Gly and Gly–Gly–Gly intercalated was almost the same as that of Phe and Gly despite increasing the number peptide bond and the molecular size. GSH was intercalated into the LDH interlayer space as GSH oxidized form with bridged LDH layers by their carboxylate groups.

The intercalation of water-soluble p-sulfonated calix[4 and 6]arene (CS4 and CS6) in the interlayer of the Mg-Al and Zn-Al layered double hydroxide (LDH) by the coprecipitation method has been investigated, as well as the adsorption properties of the resulting CS/LDHs for benzyl alcohol (BA) and p-nitrophenol (NP) to prepare new microporous organic-inorganic hybrid adsorbents. The amount and arrangement of CS intercalated was different by the kind of the host metal ions. CS4 cavity axis was perpendicular for the Mg-Al LDH basal layer and parallel for the Zn-Al LDH basal layer, while CS6 cavity axis was perpendicular for both the LDH basal layers. In the BET surface area measurement, the surface area of the Zn-Al/CS4/LDH was four times than that of the Mg-Al/CS4/LDH, expecting that the former has higher adsorption capacity than the latter. In fact, the adsorption ability of the CS/LDHs for BA and NP in aqueous solution was found to be larger in the Zn-Al/CS4/LDH than in the Mg-Al/CS4/LDH. In addition, the adsorption ability of both the LDHs was larger in the CS6/LDHs than in the CS4/LDHs. These results were explained by the difference in the amount and arrangement of CS intercalated in the LDH interlayer space.