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Surgery is one of the most effective and widely used procedures in treating human cancers, but a major problem is that the surgeon often fails to remove the entire tumor, leaving behind tumor-positive margins, metastatic lymph nodes, and/or satellite tumor nodules. Here we report the use of a hand-held spectroscopic pen device (termed SpectroPen) and near-infrared contrast agents for intraoperative detection of malignant tumors, based on wavelength-resolved measurements of fluorescence and surface-enhanced Raman scattering (SERS) signals. The SpectroPen utilizes a near-infrared diode laser (emitting at 785 nm) coupled to a compact head unit for light excitation and collection. This pen-shaped device effectively removes silica Raman peaks from the fiber optics and attenuates the reflected excitation light, allowing sensitive analysis of both fluorescence and Raman signals. Its overall performance has been evaluated by using a fluorescent contrast agent (indocyanine green, or ICG) as well as a surface-enhanced Raman scattering (SERS) contrast agent (pegylated colloidal gold). Under in vitro conditions, the detection limits are approximately 2-5 x [10.sup.-11] M for the indocyanine dye and 0.5-1 x [10.sup.-13] M for the SERS contrast agent. Ex vivo tissue penetration data show attenuated but resolvable fluorescence and Raman signals when the contrast agents are buried 5-10 mm deep in fresh animal tissues. In vivo studies using mice bearing bioluminescent 4T1 breast tumors further demonstrate that the tumor borders can be precisely detected preoperatively and intraoperatively, and that the contrast signals are strongly correlated with tumor bioluminescence. After surgery, the SpeetroPen device permits further evaluation of both positive and negative tumor margins around the surgical cavity, raising new possibilities for real-time tumor detection and image-guided surgery. 10.1021/ac102058k

The synthesis and characterization of a reversible T2 contrast agent consisting of cross-linked anionic dextran coated iron oxide nanoparticles covalently coupled to a light-sensitive spiropyran (SP)/merocyanine (MC) motif is described. The smart T2 agent has provided the advantage of reversibility that has enabled dynamic monitoring with MRI and the light responsiveness of the agent has indicated the potential to use them as MRI gene reporters for the luciferase expression system.

An effective new optical contrast agents is developed by describing the synthesis of porphyrazines (pzs) of the form [H.sub.2][pz([A.sub.4-n];[C.sub.n])] (A = peripheral heteroatom (S- and O-) R-groups and C is a fused, [bta],[bta]'-diisopropyloxynaphtho group). Emission from the oxygen-atom appended naphtho-pzs is observed within carcinoma cells, which has confirmed the cellular uptake and their potential use as optical agents.

The article explains the formation, as well as the evaluation of a new supramolecular lanthanide complex, which is shown to act as luminescent contract agent for various purposes. The Eu(III) emission of the complex is shown to be independent of the pH value and hence can be used for the imaging of the damaged bone structure.

Nanoassembled capsules (NACs) formed by using the MRI contrast agent GdDOT[P.sup.5-] in the internal polymer aggregate are described, the smaller of which has shown promise as potential MRI contrast agents. The greatest gains in relaxivity are observed for smaller NACs, for which water accessibility has remained high but molecular rotation of the [Gd.sup.3+] chelate is restricted.

The synthesis and characterization of Fe(III)-carboxylate nanoscale metal-organic frameworks (NMOFs) with the MIL-101 structure is reported. The potential use of the newly obtained NMOF-based nanodelivery vehicles for optical imaging and anticancer therapy is also demonstrated in vitro by using HT-29 human colon adenocarcinoma cells.