Pe 2400

All reagents, solvents, and deuterated were purchased from Sigma-Aldrich (Milan, Italy). Melting points were determined on Tottoli (Buchi) or Kofler apparatus and are uncorrected. Infrared spectra were recorded on a Spectrum One ATR Perkin Elmer FT-IR spectrometer, vibrational frequencies are given in ν, wave number (cm⁻¹). Nuclear magnetic resonance (¹H-NMR, ¹³C-NMR) spectra were acquired on AVANCE400 or AVANCE200 Bruker spectrometer, in DMSO, CD₃OD or CDCl₃ at 27 °C. Chemical shifts are reported in parts per million δ (ppm) relatively to TMS as internal reference, and the coupling constants (J) are expressed in Hertz (Hz). Splitting patterns are designated as follows: s, singlet; bs, broad singlet; d, doublet; t, triplet; q, quadruplet; and dd, double doublet. Mass spectra were recorded on a ThermoFinnigan LCQ Classic LC/MS/MS ion trap equipped with an ESI source and a syringe pump. Samples (10⁻⁴–10⁻⁵M in MeOH/H₂O 90:10) were infused in the electrospray system at a flow rate of 5–10 μl min⁻¹. Elemental analyses for C, H, and N were obtained by a PE 2400 (Perkin-Elmer) analyzer, and the analytical results were within ±0.4% of the theoretical values for all compounds.
Synthesis of sulfonamides 1–4:

Elemental analyses (CHN) of the samples were performed in a Perkin-Elmer PE-2400 microelemental device. The samples were characterized by X-ray diffractometry (XRD), using a Shimadzu diffractometer (model Labx-XDR 6000, Japan) operating at 40 kV and 30 mA, with Cu Kα radiation (λ = 1.5406 Å) and 3 to 75° 2θ range with a speed of first min⁻¹. The Fourier transform infrared spectroscopy (FTIR) analyses of the samples were performed in a Bruker Vertex 70 model equipment (Germany) by preparing KBr pellets at 1% (m/m). FTIR spectra were obtained with a resolution of 4 cm⁻¹, 120 scans between 4000 and 400 cm⁻¹. The morphology was carried out by scanning electron microscopy (SEM), using a field emission electron source (SEM-EC) device from FEI, model Quanta FEG-250 (Eindhoven, Netherlands). The samples were mounted on stubs using double-sided carbon tape and covered in gold. The SEM analysis conditions were from 8 to 20 kV, and the working distance was 10 mm with point 3. The thermal stability of the samples was studied using the thermogravimetry technique (TG). TG curves were obtained using the TGA-50 Shimadzu (Japan) device at 10 °C min⁻¹ heating rate in an argon atmosphere in alumina pun at 25 to 800 °C, and a mass of approximately 8 mg. Dye solutions were scanned using a UV-Vis spectrophotometer Cary 60, Agilent Technologies (USA), between 250 and 800 nm.

The prepared beads were characterized by CHN elemental analysis, FT-IR, and SEM at each reaction step.
The carbon composition of the prepared beads was measured using a CHN elemental analyzer (PE-2400, PerkinElmer, Waltham, MA, USA). The quantity of modified V-501 and PNIPAAm on the silica bead surfaces was obtained using the carbon composition of the beads (Eq. 1). $$\frac{\%C_I}{\%C_I\left(\mathit{calcd}\right)\times \left(1-\%C_I/\%C_I\left(\mathit{calcd}\right)\right)\times S^{\prime }}$$ where %C_I is the increase in carbon content after V-501 modification, %C_I (calcd) is the calculated carbon percentage of the V-501 molecule, and S is the surface area of the silica beads.
The quantity of PNIPAAm hydrogel on the silica bead surfaces was obtained using Eq. (2): $$\frac{\%C_P}{\%C_P\left(\mathit{calcd}\right)\times \left(1-\%C_P/\%C_P\left(\mathit{calcd}\right)-\%C_I/\%C_I\left(\mathit{calcd}\right)\right)\times S^{\prime }}$$ where %C_p is the increase in the carbon content of the PNIPAAm-modified beads relative to that of the V-501 modified beads, and %C_P (calcd) is the calculated carbon percentage of PNIPAAm.
Polymer modification of the silica beads surface was also confirmed by attenuated total reflection Fourier-transform infrared spectroscopy (FT/IR-4700; JASCO, Tokyo, Japan).
The bead morphologies were observed by SEM (TM4000Plus-II, Hitachi High-tech, Tokyo, Japan) for each polymer modification step.

NMR spectra were recorded on Bruker DRX-400 (¹H: 400 MHz, ¹³C: 100 MHz, ¹⁹F: 376.5 MHz) and Bruker Avance III-500 (¹H: 500 MHz, ¹³C: 126 MHz, ¹⁹F: 471 MHz) spectrometers in DMSO-d₆ and CDCl₃. The chemical shifts (δ) are reported in ppm relative to the internal standard TMS (¹H NMR), C₆F₆ (¹⁹F NMR), and residual signals of the solvents (¹³C NMR). IR spectra were recorded on a Shimadzu IRSpirit-T spectrometer using an attenuated total reflectance (ATR) unit (FTIR mode, ZnSe crystal), the absorbance maxima (ν) are reported in cm^–1. Elemental analyses were performed on an automatic analyzer PerkinElmer PE 2400. Melting points were determined using a Stuart SMP40 melting point apparatus. Column chromatography was performed on silica gel (Merck 60, 70–230 mesh). All solvents that were used were dried and distilled by standard procedures. Arylideneacetones 1 have been synthesized according to the procedure, previously described in the literature [44 (link)].

The prepared beads were characterized by CHN elemental analysis, FT–IR, and SEM to confirm immobilization of the silane layer and modification of PNIPAAm onto the silica beads.
The carbon composition of the silica beads was determined using an elemental analysis apparatus (PE-2400, PerkinElmer, Waltham, MA, USA), and the amount of silane layer was determined from the carbon composition of the beads, as shown in Eq. (1): $$\frac{\%C_S}{\%C_S\left(c,a,l,c,d\right)\times \left(1,-,\%,C_S,/,\%,C_S,(calcd.)\right)\times S},$$ where %C_S is the increase in the carbon content of the beads after the silane coupling reaction, %C_S(calcd.) is the calculated carbon percentage of the mixed silane coupling reagent (CPTMS:GPTMS = 3:1), and S is the surface area of the silica beads (100 m²/g).
Further, the amount of PNIPAAm brush on the silica beads was obtained as follows: $$\frac{\%C_N}{\%C_N\left(c,a,l,c,d\right)\times \left(1,-,\%,C_N,/,\%,C_N,\left(c,a,l,c,d,.\right),-,\%,C_S,/,\%,C_S,(calcd)\right)\times S},$$ where %C_N is the increase in the carbon content of the beads after ATRP and %C_N(calcd) is the calculated carbon percentage of NIPAAm.
Modification of the polymer via ATRP was confirmed by observing the IR spectrum of the beads via ATR/FT–IR (FT/IR-4700; JASCO, Tokyo, Japan).
The morphology of the silica beads at each reaction step was observed using SEM (TM4000Plus-II, Hitachi High-Tech, Tokyo, Japan).