Results

  a)  The preparation and caracterization of thin gold layers deposited on mica and gold nanoparticles in suspenssion, respectively.

•  Thin gold layers were obtained termal evaporation of gold in vacuum and subsequent deposition of vapors on mica support.
• Gold nanoparticles were prepared. The technique used consists of improving our original method used for gold colloids preparation through the reduction technique. The reduction agent was Na₃Au(SO₃)_2.
• The thin gold layers and gold nanoparticles morphology were characterized through electron microscopy, atomic force microscopy and X-ray diffraction. The thin gold layers are quite uniform and has around 700 nm. X-ray difractogram show a polycrystalline structure of gold layers with crystallites bigger then 100 nm. The surface of gold layers has a granular morphology with a granularity range of 25-45 nm.
• The electron microscopy images show spherical nanoparticles with 15-25 nm range of dimensions. X-ray difractograms shows nanocrystallites withpreferential orientation along (111) crystallographic plan. The average dimension of nanocrystallites calculated from Sherrer equation is around 20 nm.

b)   Numerical simulations of minimum energy structures and NMR spectra for bithiophene-phenothiazine podands.

•    The minimum energy structures and chemical shifts of hydrogen spectral lines were calculated for 4 phenothiazinic molecular compounds:

•  The RMN-H¹ theoretical spectra provide useful information about molecular symmetry of studied systems and equivalent protons spectral shifts can identify different molecular structures that appear during synthesis process.

  c)   The design, synthesis and structural analysis for some phenothiazinic and macrocyclic derivates with phenothiazinic units.

•  Bi- and ter-thiophenic derivates were synthesized these being subsequently used to obtain macrocycle derivates.
• The design of the final compounds was elaborated as well as the synthesis strategy for obtaining the podands required to obtain the macrocycles derivates with bi-thiophenic and phenothiazinic units.

 d)  The investigation of the physical and chemical properties of the bi-thiophene-phenothiazine podands through: cyclic voltametry, NMR and fluorescence spectroscopy.

       Three phenothiazinic organic compounds were caracterised:

•  10H-ethyl phenothiazine
•  10H-ethyl-3,7-bis(4,4,5,5-tetramethyl[1.3.2]dioxaborolane-2) phenothiazine
• 10H-ethyl-3,7-bis(4-hydroxyazobenzene-3) phenothiazine

To characterize the screening effect of the gold electrodes the cyclic voltammograms were obtained. The main conclusion: characterized the shielding effect of gold electrodes. The main conclusion: The degree to which the molecules are attached to the gold electrode surface is dependent on the number of the characteristic functional units, on their dimensions and on their spatial position.

Stage II

Characterization of the bi-thiophene-phenothiazine podands in solution and deposited on gold surfaces by:

a)    IR and UV/VIS spectroscopy.

• The FTIR spectra were obtained for four new compounds from the bi-thiophene-phenothiazine family. The spectra allow the identification and assignment of the main spectral lines which characterise the vibrational modes of the new molecular species.
• Specular reflection spectra as well as Attenuated Total Reflection (ATR) Infrared spectra were measured to obtain information about the molecular monolayer deposited on the supported gold films
• The same four types of phenothiazinic podands were characterised by UV/VIS spectroscopy and the main spectral bands corresponding to the electronic transitions were identified.
• The UV/VIS spectra have been obtained for the gold nanoparticles on which the four types of phenothiazinic podands were deposited and the change of the plasmonic band was observed.
• The UV/VIS spectra of SBSSs with bi-thiophene-phenothiazine compounds are very similar to the substrate spectra and,therefore, suggest that means that the investigation technique is not sensitive enough to characterise the prepared SBSSs.

b)   Fluorescence spectroscopy.

• Excitation and emision spectra were obtained for three types of phenothiazinic podands which exhibit fluorescence in solution. Multiple emission spectra have been recorded for each compound by excitation at several wavelengths which were appropriately chosen to correspond to the maxima of the excitation spectrum.
• The SBSSs fluorescence spectra could be measured only for certain compounds. As opposed to the UV/VIS spectra, in the fluorescence case, the presence of the compounds brings significant contributions.

c)   Cyclic voltametry

a)    The geometrical structure of the molecules, free or attached to gold surfaces, were determined by methods of molecular modelling for the following compounds:

• 3-(3’,7’-dibromo-10’H-phenotiazin-yl) propyl-thioacetate
• 6-(3’,7’-dibromo-10’H-phenotiazin-yl) hexyl-thioacetate
• 6-[ 3’,7’-bis(5’-methylene-thien-2’-yl)- 5’,5’-tetraethylenoxi-10’H-phenotiazin-yl) hexyl-thioacetate

b)    The NMR spectra of the following phenothyazinic compounds were numerically simulated:

• 6-(3’,7’-dibromo-10’H-phenotiazin-10-yl) hexyl-thioacetate
• 5,5’-tetraethylenoxi-3-(3,7-bis(5’-thiophen-2’-yl)-10H-phenothiazin-10-yl)-propane-1-thiol
• 3,7-bis(4’-methylenoxi-azobenzene)-1”,4”-dioxa-2”,3”-dimercaptomethyl benzene -10H- phenothiazin- 10-yl ethane
• 3,7-bis( p-tolyl-4-yl)- 4,4’-tetraethylenoxi- 10H- phenotiazin-10-yl ethane
• 6-[3,7-bis( 4’-hydroxi-azobenzene)-10H-phenothiazin-10-yl)] hexane-1-thiol

c)    The following macrocycles with phenothiazinic, tiophenic and azobenzenic units were obtained:

• 6-(3’,7’-dibromo-10’H-phenotiazin-10-yl) hexyl-thioacetate
• 6-(3’,7’-dibromo-10’H-phenothiazin-10-yl) hexane-1-thiol
• 3,7-bis(m-phenilen)- 3,3’-tetraethylenoxi-10H- phenothiazin-10-yl ethane - (M4EG)
• 6-[3,7-bis(4’-hydroxi-azobenzene) -10H-phenothiazin-10-yl)] hexane-1-thiol

d)    The physico-chemical properties of the prepared compounds, in solution or deposited on gold surface, were characterised by:

• UV-VIS, IR and fluorescence spectroscopy
• Mass spectrometry
• NMR spectroscopy
• Cyclic voltametry
• Atomic force microscopy
• X-ray diffraction

e)    SBSSs were obtained through the deposition of prepared compounds on gold surfaces, gold nanoparticles., respectively.

f)    The morphology and the physico-chemical and structural properties of the SBSSs were characterised by:

• Cyclic voltametry
• Fluorescence spectroscopy
• Atomic force microscopy
• Fluorescence microscopy

a)    An Isothermal Titration Calorimeter (ITC) was acquired and it was tested with the water-ethanol binary system.

b)    The geometrical structures of two phenothiazinic macrocycles were obtained by applying a computer code based on the Density Functional Theory method:

• 3,7-bis(2,5-di(thiophen-2-yl)thiophene)-2’,3’- dimethyl-1’,4’-dioxa-benzene- 10H-benzyl phenothiazine (BTTDMNBPT)
• 3,7-bis(2,5-di(thiophen-2-yl)thiophene)-2’,3’- dimercaptomethyl-1’,4’- dioxa-benzene-10H-benzyl -10-yl-phenothiazine (BTTDTiolNBPT)

c)    The design, synthesis and structural analysis of some phenothiazinic compounds were obtained:

• 3,7-bis(2,5-di(thiophen-2-yl)thiophene)-2’,3’-dimercaptomethyl-1’,4’ dioxabenzene-10H-benzyl-10-yl phenothiazine (BTTDTiolNBPT)
• 1,2-bis(8-(3,7-dibromo-10H-phenothiazin-10-yl)octyl)disulfane (BTiol8CH)
• 8-(3,7-dibromo-10H-phenothiazin-10-yl)octane-1-thiol(Tiol8CH)
• 2,5-di(thiophen-2-yl)thiophene (TT)
• 2,5-bis(m-phenyl)-3’, 3’-triethylenoxi-thiophene (ETDPhT)
• 2-(3-(2-(3-(thiophen-2-yl)phenoxy) triethoxy-phenyl)-5-(3-2(m-tolyloxy) triethoxy) phenyl) thiophene (PETDPhT)

d)    The physico-chemical and structural analysis of the phenothiazinic macrocyclic compunds was realised and the changes induced by complexation with various cations were observed. The methods used in this respect were the UV-VIS and fluorence spectroscopy for compunds 1 - 5, isothermal titration calorimetry for the compounds 5 and 6, the cyclic voltametry for the compounds 1 – 5 and X-ray diffraction for the compounds 2, 4 - 5:

• 8-(3,7-dibromo-10H-phenothiazin-10-yl)octane-1-thiol (Tiol8CH)
• 1,2-bis(8-(3,7-dibromo-10H-phenothiazin-10-yl)octyl)disulfane (BTiol8CH)
• 2,5-di(thiophen-2-yl)thiophene (TT)
• 2,5-bis(m-phenyl)-3’, 3’-triethylenoxi-thiophene (ETDPhT)
• 2-(3-(2-(3-(thiophen-2-yl)phenoxy) triethoxy-phenyl)-5-(3-2(m-tolyloxy) triethoxy) phenyl) thiophene ( PETDPhT)
• 18-crown -6 ether

e)    SBSSs were obtained by depositing the phenothiazinic macrocyclic compounds on gold surfaces (111) and gold nanoparticles, respectively:

• 3,7-bis(2,5-di(thiophen-2-yl)thiophene)-2’,3’-dimercaptomethyl-1’,4’- dioxabenzene-10H-benzyl-10-yl phenothiazine (BTTDTiolNBPT)
• 1,2-bis(8-(3,7-dibromo-10H-phenothiazin-10-yl)octyl)disulfane (BTiol8CH)

f)    The morphology and the physico-chemical properties of the SBSSs were charcterised by atomic force microscopy and infrared spectroscopy.

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