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The present work aims to provide a framework for teaching nanotechnology for life sciences applications, with special focus on nanotechnology-enabled treatments based on advanced physical and biological principles. By expanding and adapting the so-called “Big Ideas” of NSE to further include core elements of cell and molecular biology, an eight-level learning progression is suggested. The challenges of teaching nanotechnology are further addressed in different learning contexts to highlight the importance of size-dependent physical and biological interactions. A number of core nanomedicine concepts are discussed, including, e.g., directed self-assembly, enhance permeability and retention effect, protein corona, size-dependent cellular uptake, disease-specific environment, and theranostics. The outcome of this work will be useful for educators designing curriculum with specialization in nanomedicine.

In this study, systematic analysis of nanotechnology education programmes was carried out from a global and local perspective. Although several universities offer 3-4 year nanotechnology-centred educational programmes, in general the most common modes for nanotechnology education include either modular courses integrated in traditional scientific disciplines or 2-year specialised MSc programmes. Nanotechnology education has a number of peculiarities. For example, it is common to include “nano”-labelling of education for marketing purposes to attract students to study traditional disciplines. Another conclusion of the analysis is that specialised nanotechnology programmes require access to advanced characterisation equipment, which can be limiting for programmes with small number of students. The nanotechnology education in Sweden does not differ much from other countries in its structure. MSc programmes or modular courses in nanotechnology are offered by major universities. Lund University and KTH offer 2-year MSc programmes with specialisation in nanoscience, having strong focus on nanoelectronics and nanophysics, whereas Chalmers is offering nanoelectronics as a part of international 2-year Erasmus Mundus MSc programme in nanoscience and nanotechnology- EMMNano. The nanotechnology education at Uppsala University is conducted mainly through modular courses, with significantly higher number of courses specialised in life sciences applications than that at other major Swedish universities. At this time, it appears that no 2-year MSc programme is offered by major Swedish universities with specialisation in nanomedicine. Finally, extensive analysis of nanotechnology for life science education is conducted to highlight core concepts in the field.

The poor permeability of theranostic agents across the blood-brain barrier (BBB) significantly hampers the development of new treatment modalities for neurological diseases. A new biomimetic nanocarrier is discovered using heparin (HP) that effectively passes the BBB and targets glioblastoma. Specifically, HP-coated gold nanoparticles (HP-AuNPs) are designed that are labeled with three different imaging modalities namely, fluorescein (FITC-HP-AuNP), radioisotope (68)Gallium (Ga-68-HP-AuNPs), and MRI active gadolinium (Gd-HP-AuNPs). The systemic infusion of FITC-HP-AuNPs in three different mouse strains (C57BL/6JRj, FVB, and NMRI-nude) displays excellent penetration and reveals uniform distribution of fluorescent particles in the brain parenchyma (69-86%) with some accumulation in neurons (8-18%) and microglia (4-10%). Tail-vein administration of radiolabeled Ga-68-HP-AuNPs in healthy rats also show Ga-68-HP-AuNP inside the brain parenchyma and in areas containing cerebrospinal fluid, such as the lateral ventricles, the cerebellum, and brain stem. Finally, tail-vein administration of Gd-HP-AuNPs (that displays approximate to threefold higher relaxivity than that of commercial Gd-DTPA) in an orthotopic glioblastoma (U87MG xenograft) model in nude mice demonstrates enrichment of T1-contrast at the intracranial tumor with a gradual increase in the contrast in the tumor region between 1 and 3 h. It is believed, the finding offers the untapped potential of HP-derived-NPs to deliver cargo molecules for treating neurological disorders.

PURPOSE: With the ambition of improving the management of pancreatic neuroendocrine tumors (P-NETs), we developed and preliminary validated a novel fluorine-18 labelled HSP90 ligand. METHODS: A precursor containing methoxymethyl ethers protecting groups and a tosyl as leaving group was synthesized. The target compound was labeled with nucleophilic 18F-fluoride and the protecting groups was subsequently removed with hydrochloric acid before purification. In vitro cell- and frozen section autoradiography and in vivo animal studies were performed. RESULTS: The precursor was successfully synthesized and utilized in the 18F-radiolabeling giving 0.5-1.0 GBq of pure product with a synthesis time of 70 min. In vitro experiments indicated a high specific binding, but in vivo studies showed no tumor uptake due to fast hepatobiliary metabolism and excretion. CONCLUSIONS: Despite the unfavorable in vivo properties of the tracer, the promising results from in vitro autoradiography experiments in frozen sections of P-NETs from surgical resection encourage us to continue the project aiming the improvement of in vivo properties of the tracer., De två första författarna delar förstaförfattarskapet

Herein we describe the development of new methodologyfocusing on 11C-labelling of sulfonyl carbamates in a multicomponentreaction comprising a sulfonyl azide, an alkyl alcohol and [11C]CO. Anumber of 11C-labelled sulfonyl carbamates were synthesised andisolated, and the developed methodology was then applied in thepreparation of a biologically active molecule. The target compoundwas obtained in 18±8% isolated radiochemical yield and wasevaluated for binding properties in a tumor cell assay, as well asundergoing in vivo biodistribution and imaging studies. Thisrepresents the first successful radiolabelling of C21, a non-peptideangiotensin II receptor subtype 2 agonist currently in clinical trials.

Background The serotonin precursor 5-hydroxy-L-[β-11C]tryptophan ([11C]HTP) is in clinical use for localization of neuroendocrine tumors and has been suggested as a proxy marker for pancreatic islet cells. However, degradation by monoamine oxidase-A (MAO-A) reduces retention and the contrast to non-endocrine tissue. Methods A synthesis method was developed for 5-hydroxy-L-[β-11C2H]tryptophan ([11C]DHTP), an isotopologue of [11C]HTP, labeled with 11C and 2H at the β-position adjacent to the carbon involved in MAO-A decarboxylation. MAO-A-mediated degradation of [11C]DHTP was evaluated and compared to non-deuterated [11C]HTP. Results [11C]DHTP was synthesized with a radiochemical purity of >98%, radioactivity of 620 ± 190 MBq, and deuterium (2H or 2H2) incorporation at the β-position of 22% ±5%. Retention and resistance to MAO-A-mediated degradation of [11C]DHTP were increased in cells but not in non-human primate pancreas. Conclusions Partial deuteration of the β-position yields improved resistance to MAO-A-mediated degradation in vitro but not in vivo.

Choline kinase alpha is hyperactivated in many solid tumours and regulates malignant progression, making it a promising cancer drug target. The successful design and synthesis of novel inhibitors with high cellular activity are described.

Expression of the gastrin-releasing peptide receptor (GRPR) in prostate cancer suggests that this receptor can be used as a potential molecular target to visualize and treat these tumors. We have previously investigated an antagonist analog of bombesin (D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH2, RM26) conjugated to 1,4,7-triazacyclononane-N,N',N ''-triacetic acid (NOTA) via a diethylene glycol (PEG(2)) spacer (NOTA-P2-RM26) labeled with Ga-68 and In-111. We found that this conjugate has favorable properties for in vivo imaging of GRPR-expression. The focus of this study was to develop a F-18-labelled PET agent to visualize GRPR. NOTA-P2-RM26 was labeled with F-18 using aluminum-fluoride chelation. Stability, in vitro binding specificity and cellular processing tests were performed. The inhibition efficiency (IC50) of the [F-nat]AlF-NOTA-P2-RM26 was compared to that of the Ga-nat-loaded peptide using I-125-Tyr(4)-BBN as the displacement radioligand. The pharmacokinetics and in vivo binding specificity of the compound were studied. NOTA-P2-RM26 was labeled with F-18 within 1 h (60-65% decay corrected radiochemical yield, 55 GBq/mu mol). The radiopeptide was stable in murine serum and showed high specific binding to PC-3 cells. [F-nat]AlF-NOTA-P2-RM26 showed a low nanomolar inhibition efficiency (IC50=4.4 +/- 0.8 nM). The internalization rate of the tracer was low. Less than 14% of the cell-bound radioactivity was internalized after 4 h. The biodistribution of [F-18]AlF-NOTA-P2-RM26 demonstrated rapid blood clearance, low liver uptake and low kidney retention. The tumor uptake at 3 h p. i. was 5.5 +/- 0.7 % ID/g, and the tumor-to-blood, -muscle and -bone ratios were 87 +/- 42, 159 +/- 47, 38 +/- 16, respectively. The uptake in tumors, pancreas and other GRPR-expressing organs was significantly reduced when excess amount of non-labeled peptide was co-injected. The low uptake in bone suggests a high in vivo stability of the Al-F bond. High contrast PET image was obtained

Huisgen cycloaddition is attractive to label peptide because of its rapidity and bioorthogonality. However, for larger tracers, the physico-chemical differences between the precursor and the tracer are usually insufficient to allow their separation by HPLC, reducing the specific activity. This is of importance for peptidic tracers because the combination of their high-affinity receptor with low specific activity results in the precursor saturating the receptors, causing non-specific tracer binding. Here, we report a fast, one-pot, general strategy to circumvent this issue, yielding a tracer of improved specific activity. It consists in adding a lipophilic azide after the labeling step to scavenge unreacted precursor into a more lipophilic species that does not co-elute with the tracer. We applied this strategy to a new fluorinated cyclopentapeptidic CXCR4 antagonist for the PET imaging of cancer, CCIC15, for which we managed to reduce the apparent peptide concentration by a factor of 34 in 10min. This tracer was radiolabeled by click chemistry with 2-[F-18]fluoroethylazide, yielding the tracer in 18 +/- 6% (n=5) end-of-synthesis radiochemical yields (EOS-RCY) in 1.5h from [F-18]fluoride with a specific activity of 19.4GBq mu mol(-1). Preliminary biological evaluation of the probe confirmed potency and specificity for CXCR4; further biological evaluation is underway.

Combinatorial synthesis is extensively used in drug development and lead optimisation. However, this approach has rarely been used for positron emission tomography because of limitations in available technologies. [11C]Carbon monoxide is amenable to combinatorial synthesis in transition-metal-catalysed reactions because it can react with a wide variety of electrophiles and nucleophiles, which opens up the possibilities for combinatorial radiochemistry. Herein, we exemplify the combinatorial approach by 11C-labelling a library of epidermal growth factor receptor inhibitors. The selection of candidates was guided by molecular docking. Epidermal growth factor receptor is overexpressed in a variety of tumours, and it has become an important drug target. The 11C-labelling reactions were performed using four substituted vinyl iodides and three different 4-anilino-6-aminoquinazolines using a palladium-mediated reaction with [11C]carbon monoxide using a single set of reaction conditions. In total, 12 labelled acrylamide derivatives were radiolabelled and obtained in 24–61% decay-corrected radiochemical yield (from [11C]carbon monoxide). Starting from 5.6 GBq [11C]carbon monoxide, 0.85 GBq of formulated N-[4-(3-bromo-phenylamino)-quinazolin-6-yl]-acryl[11C]amide [11C]12da was obtained within 47 min from end of bombardment (specific activity of 60 GBq µmol−1). This strategy is an example of how [11C]carbon monoxide can be utilised in the labelling of libraries of drug candidates and positron emission tomography tracers for in vitro and in vivo testing.

The urea moiety is present in many biologically active compounds and thus an attractive target for C-11-labelling. To extend the scope of the rhodium(I)-mediated carbonylative cross-coupling reaction between an azide and an amine and investigate its tolerance for functional groups, we have synthesized eight ureas and two sulphonylureas that were C-11-labelled in the carbonyl position. The decay-corrected analytical radiochemical yields were in the range of 14-96% (from [C-11] carbon monoxide). For example: starting from 1.33 GBq [C-11] carbon monoxide, 0.237 GBq (66%) of the cytotoxic sulphonylurea [C-11] LY-181984 11 was isolated within 60 min from end of bombardment. The mild reaction conditions and generality regarding functional groups of this method make it an attractive alternative to the [C-11] phosgene method for the synthesis of C-11-labelled ureas.

Three C-11-radiolabelled high-affinity nonpeptide AT(2) receptor-selective ligands were synthesized and one of these was evaluated as positron emission tomography (PET) tracer. The labelling reaction was performed via palladium(0)-mediated aminocarbonylation of the aryl iodide substrate using [C-11] carbon monoxide as the labelled precursor. As an example, starting with 10.0 GBq [C-11] carbon monoxide, 1.10 GBq of the product N-butoxycarbonyl-3-[4-(N-benzyl-[C-11] carbamoyl)phenyl]-5-isobutylthiophene-2-sulphonamide [C-11]4d was obtained in 36% decay-corrected radiochemical yield (from [C-11] carbon monoxide), 42 min from end of bombardment with a specific activity of 110 GBq.mu mol(-1). The N-isopropyl-[C-11] carbamoyl-analogue [C-11]4c (radiochemical purity >95%) was studied employing autoradiography, organ distribution, and small animal PET. In vitro autoradiography showed specific binding in the pancreas and kidney. Organ distribution in six rats revealed a high uptake in the liver, intestine, kidney, and adrenals. Small animal PET showed rapid and reversible uptake in the kidneys followed by accumulation in the urinary bladder suggesting fast renal excretion of the tracer. In addition, high accumulation was also seen in the liver. For future studies, more metabolically stable tracers will need to be developed. To the best of our knowledge, this is the first attempt of the use of PET imaging for the detection of expressed, fully functional AT(2) receptors in living subjects.

Essential hypertension occurs in approximately 25% of the adult population and one cause of hypertension is primary aldosteronism. Targeting the angiotensin II AT1 receptor using PET and an appropriate tracer may offer a diagnostic method for adrenocortical tissue. This report describes the synthesis of the selective AT1 receptor antagonist [carboxyl-11C]eprosartan 10, 4-[2-butyl-5-((E)-2-carboxy-3-thiophen-2-yl-propenyl)-imidazol-1-ylmethyl]-[carboxyl-11C]benzoic acid, and its precursor (E)-3-[2-butyl-3-(4-iodo-benzyl)-3H-imidazol-4-yl]-2-thiophen-2-ylmethyl-acrylic acid 9. 11C-carboxylation of the iodobenzyl moiety was performed using a palladium-mediated reaction with [11C]carbon monoxide in the presence of tetra-n-butyl-ammonium hydroxide in a micro-autoclave using a temperature gradient from 25 to 140°C over 5 min. After purification by semipreparative HPLC, [carboxyl-11C]eprosartan 10 was obtained in 37–54% decay-corrected radiochemical yield (from [11C]carbon monoxide) with a radiochemical purity >95% within 35 min of the end of bombardment (EOB). A 5-µAh bombardment gave 2.04 GBq of 10 (50% rcy from [11C]carbon monoxide) with a specific activity of 160 GBq µmol−1 at 34 min after EOB. Frozen-section autoradiography shows specific binding in kidney, lung and adrenal cortex. In vivo experiments in rats demonstrate a high accumulation in kidney, liver and intestinal wall.

As part of our ongoing investigation into the imaging of angiogenic processes, a small library of eight vascular endothelial growth factor receptor-2 (VEGFR-2)/platelet-derived growth factor receptor beta dual inhibitors based on the N-phenyl-N'-4-(4-quinolyloxy)-phenyl-urea was labelled with C-11 (beta(+), t(1/2) = 20.4 min) in the urea carbonyl position via rhodium-mediated carbonylative cross-coupling of an aryl azide and different anilines. The decay-corrected radiochemical yields of the isolated products were in the range of 38-81% calculated from [C-11]carbon monoxide. Starting with 10.7+/-0.5 GBq of [C-11]carbon monoxide, 1-[4-(6,7-dimethoxy-quinolin-4-yloxy)-3-fluoro-phenyl]-3-(4-fluoro-phenyl)-[C-11]-urea (2.1 GBq) was isolated after total reaction time of 45 min with a specific activity of 92+/-4 GBq mu mol(-1).

Two methods are presented for the synthesis of acrylamides labelled with C-11 (beta(+), t(1/2) = 20.4 min) and C-11 in the carbonyl position. In the first method, [1-C-11]acrylic acid is synthesised from [C-11]carbon monoxide by palladium-mediated hydroxy-carbonylation of acetylene. The labelled carboxylic acid is converted into the acyl chloride and subsequently treated with amine to yield N-benzyl[carbonyl(11)C]acrylamide, The second method utilizes [C-11]carbon monoxide in a palladium-mediated carbonylative cross-coupling of vinyl halides and amines. A higher radiochemical yield is achieved with the latter method and the amount of amine needed is decreased to 1/20. The C-11-labelled acrylamides were isolated in up to 81 % decay-corrected radiochemical yield. Starting from 10 +/- 0.5GBq of [C-11]carbon monoxide, N-benzyl[carbonyl-C-11]acrylamide was obtained in 4 min with a specific radioactivity of 330 +/- 4 GBq mu mol-(1). Co-labelling with C-11 and C-13 enabled confirmation of the labelled position by C-13 NMR spectroscopy.

PurposePolyvinylalcohol-carbazate (PVAC) is a soluble functionalized polymer acting as a carbonyl scavenger. This study aimed to create a radiolabelled PVAC and investigate the pharmacokinetics and biodistribution of PVAC in naïve animals and ischemia models. MethodsPVAC was labelled using radionuclide [18F]FBA to track the substance with PET. Sprague Dawley rats underwent an ischemic event, either to the hind limb or to the kidney, while others served as controls. To study the pharmacokinetics rats were injected with radiolabelled or fluorochrome labelled PVAC. Radiolabelled PVAC was injected, and animals were followed by PET for 90 min, biodistribution ex vivo was finally examined. Injection of fluorochrome-labelled PVAC was followed by repeated blood sampling to measure the circulating concentration. ResultsIn control animals, PVAC was mainly confined to the bloodstream followed by elimination via kidneys and accumulation in the bladder. Ex vivo biodistribution of PVAC confirmed the highest uptake in urine followed by blood, kidneys and other well-perfused organs. The elimination of I.V. administered PVAC was split into a fast phase (t1/2 = 0.2 h) followed by a slow phase (t1/2 = 10.73 h), with near-complete elimination from blood after 48 h. Both the ischemic kidney (fourfold increase, p = <0.001) and limb models (threefold increase, p = <0.001) demonstrated a higher uptake of PVAC in ischemic tissues, ex vivo radioactivity detection. ConclusionLabelled PVAC, an aldehyde-carbonyl scavenger, is a promising new strategy to detect ischemic tissues. Potential therapeutic effects of PVAC on ischemic injuries should be investigated further.