The design and synthesis of a novel reduction-sensitive, robust, and biocompatible vesicle (SSCB[6]VC) are reported, which is self-assembled from an amphiphilic cucurbit[6]uril (CB[6]) derivative that contains disulfide bonds between hexaethylene glycol units and a CB[6] core. The remarkable features of SSCB[6]VC include: 1) facile, non-destructive, non-covalent, and modular surface modification using exceptionally strong host-guest chemistry; 2) high structural stability; 3) facile internalization into targeted cells by receptor-mediated endocytosis, and 4) efficient triggered release of entrapped drugs in a reducing environment such as cytoplasm. Furthermore, a significantly increased cytotoxicity of the anticancer drug doxorubicin to cancer cells is demonstrated using doxorubicin-loaded SSCB[6]VC, the surface of which is decorated with functional moieties such as a folate-spermidine conjugate and fluorescein isothiocyanate-spermidine conjugate as targeting ligand and fluorescence imaging probe, respectively. SSCB[6]VC with such unique features can be used as a highly versatile multifunctional platform for targeted drug delivery, which may find useful applications in cancer therapy. This novel strategy based on supramolecular chemistry and the unique properties of CB[6] can be extended to design smart multifunctional materials for biomedical applications including gene delivery.

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Dehydrated carrot pomace was added in different proportions (10-30%) to rice flour. The formulation was extruded at different moisture content (17-21%), screw speed (270-310 rpm) and die temperature (110-130°C). The experimental combinations were decided based on central composite rotatable design for four variables at five levels of each variable. The lateral expansion, bulk density, water absorption index, water solubility index, hardness and sensory characteristics were measured as responses. Significant regression models were established with the coefficient of determination, R² greater than 0.70. The results indicated that pomace proportion, screw speed and temperature significantly influenced (P<0.10) lateral expansion; moisture content and screw speed for bulk density; pomace proportion and temperature for water absorption index and water solubility index, pomace proportion, screw speed and temperature for hardness and screw speed for sensory score. The compromised optimum condition obtained by numerical integration for development of extrudates were: carrot pomace of 11.75% in rice flour, moisture content 19.92%, screw speed 249.1 rpm and die temperature 114.3°C. Sensory evaluation revealed that carrot pomace could be incorporated into ready-to-eat expanded products upto the level of 11.75%.

Thin layer carrot pomace drying characteristics were evaluated in a laboratory scale hot air forced convective dryer. The drying experiments were carried out at 60, 65, 70 & 75 °C and at an air velocity of 0.7 m/s. Mathematical models were tested to fit drying data of carrot pomace. The whole drying process of carrot pomace took place in a falling rate period except a very short accelerating period at the beginning. The average values of effective diffusivity ranged from 2.74 × 10(-9) to 4.64 × 10(-9) m(2)/s for drying carrot pomace. The activation energy value was 23.05 kJ/mol for the whole falling rate period.

Reaction of [Cu(CH(3)CN)(4)](PF(6)) and NH(4)[S(2)P(OR)(2)] in a 4:3 ratio in acetone at room temperature produces octanuclear dicationic copper complexes [Cu(8){S(2)P(OR)(2)}(6)](PF(6))(2) (R = (i)Pr, 1; Et, 3) in 81 and 83% yields, respectively. On the other hand, reaction of [Cu(CH(3)CN)(4)](PF(6)), NH(4)[S(2)P(OR)(2)], and NaBH(4) in an 8:6:1 molar ratio in THF for 1 h yields [Cu(4)(H)(mu(3)-Cu)(4){S(2)P(OR)(2)}(6)](PF(6)) (R = (i)Pr, 2a; Et, 4a) in 87 and 82% yields, respectively. In a similar reaction when NaBD(4) is used instead of NaBH(4), [Cu(4)(D)(mu(3)-Cu)(4){S(2)P(OR)(2)}(6)](PF(6)) (R = (i)Pr, 2b; Et, 4b) are obtained in 83 and 78% yields, respectively. Structural elucidations of 2a and 4a reveal the tetracapped tetrahedral Cu(8) cage with an interstitial hydride. Each of the Cu(I) centers is trigonally coordinated by three S atoms, and each of the six dithiophosphate ligands is connected to a Cu(4) butterfly, where the hinge positions are occupied by two copper atoms situated at the vertex of the central tetrahedron and the wingtips are two capping Cu atoms. The 12 S atoms out of the six ligands constitute an icosahedron around the hydride-centered tetracapped tetrahedral Cu(8) framework. Surprisingly, empty Cu(8) clusters 1 and 3 can abstract hydride (or deuteride) from NaBH(4) (or NaBD(4)) in THF to form 2a and 4a (or 2b and 4b), respectively. Apparently the cubic Cu(8) core, which is known to be formed in the reaction of Cu(I) salt and dichalcogenophosph(in)ate ligands, undergoes a tetrahedral contraction due to the strong Cu...H interactions. Interestingly, the chloride can also be replaced from the chloride-centered Cu(8) complex of [Cu(8)(Cl){S(2)P(OEt)(2)}(6)](PF(6)) by hydride (or deuteride) to form 2a and 4a (or 2b and 4b). However, the hydride- and deuteride-centered compounds 2a,b and 4a,b do not allow the guest exchange.