Density Functional Theory-Assisted Electrochemical Assay Manipulated by a Donor-Acceptor Structure toward Pharmaceutical Diagnostic

Oxidative stress is a state of stress injury, which leads to the pathogenesis of most neurodegenerative diseases. Moreover, this is also one of the main reasons for the loss of dopaminergic neurons and the abnormal content of dopamine (DA). In the past decades, a number of studies have found that acetaminophen (AP) is metabolized and distributed in the brain when it is used as a neuroprotective compound. In this context, we proposed an electrochemical sensor based on 9-(4-(10-phenylanthracen-9-yl)phenyl)-9H-carbazole with the goal of diagnosing these two drugs in the body. Carbazole groups can easily be formed into large π-conjugated systems by electropolymerization. The introduction of anthracene exactly combined the carbazole group to establish an efficient electron donor-acceptor pattern, which enhanced π-π interaction with the electrode surface and charge transporting ability. The diagnostic platform showed good sensing activity toward the oxidation of DA and AP. The detection range for DA and AP is from 0.2 to 300 μM and from 0.2 to 400 μM, respectively. The simultaneous detection range is from 0.5 to 250 μM, which is wider than most reports. After a series of electrochemical assessments were determined, the sensor was finally developed to the analysis of pharmaceutical and human serum, displaying a meaningful potential in clinical evaluation.

Design Rules for Improving the Cycling Stability of High-Performance Donor-Acceptor-Type Electrochromic Polymers

Although high-performance donor-acceptor (D-A)-type polymers have received much attention as an important class of electrochromic (EC) materials, the related studies have mostly focused on the influence of D and A units on the band gap, onset potential, and switching time, leaving the effect of D-A structures on cycling lifetime underexplored. Herein, we design and synthesize a series of poly(aryl amino sulfone)s (PAASs) as D-A polymers with triphenylamine-based donor units and the sulfone moiety as the acceptor unit. As a result, we present new rules to design and develop D-A structure polymers with high EC cycling stability: (1) the electron-donating and -withdrawing abilities of the donor and acceptor should be balanced during the electrochemical cycle process, and this balance can be measured by the ratio of J_red/J_ox; (2) the D-A structure should benefit to generate lower E_onset. By these design rules, the best-performing polymer PAAS-TPPA-OMe exhibits an excellent long-term cycling stability (over 3,900 cycles), low onset potential (0.26 V), fast switching time (6.0/4.3 s for the EC process), high contrast (87% at 688 nm and 94% at 928 nm), and high coloration efficiency (500 cm² C^-1 at 688 nm and 1131 cm² C^-1 at 928 nm).

Recent advances in triphenylamine-based electrochromic derivatives and polymers

Triphenylamine-containing electrochromic materials with great potential applications in low energy-consumption displays, light-adapting mirrors in vehicles, and smart windows have experienced an exponential growth of research interests. In this review, the newly developed triphenylamine-based derivatives and polymers are reviewed and elaborated.

Facile Synthesis of Electroactive and Electrochromic Triptycene Poly(ether-imide)s Containing Triarylamine Units via Oxidative Electro-Coupling

Two bisimide compounds, TPA–TPDI and NPC–TPDI, consisting of a triptycene core and two triphenylamine (TPA) or N-phenylcarbazole (NPC) end groups were successfully synthesized by the condensation reactions from 1,4-bis(3,4-dicarboxyphenoxy)triptycene dianhydride with 4-aminotriphenylamine and N-(4-aminophenyl)carbazole, respectively. These two monomers could polymerize electrochemically via the oxidative coupling reactions of triarylamine units. The electrochemical and spectroelectrochemical properties of the electro-generated triptycene poly(ether-imide)s (TPA–TPPI and NPC–TPPI) were studied. Both polymers have two colored oxidation states, and TPA–TPPI showed better electrochromic performance than NPC–TPPI.

Electrochemical synthesis, optical, electrochemical and electrochromic characterizations of indene and 1,2,5-thiadiazole-based poly(2,5-dithienylpyrrole) derivatives

PBDTA/PProDOT-Et₂ ECD showed high ΔT_max (43.8%) and satisfactory cyclic voltammetry stability, whereas P(BDTA-co-DTP)/PProDOT-Et₂ ECD showed high ΔT_max (44.0%) and coloration efficiency (504.6 cm² C⁻¹).

Electrochemically fabricated electrochromic films from 4-(N-carbazolyl)triphenylamine and its dimethoxy derivative

4-(N-Carbazolyl)triphenylamine (TPACz) and its methoxy derivative MeOTPACz could be facilely fabricated into redox-active and electrochromic PTPACz polymer and (MeOTPACz)2 dimer films via electrochemical polymerization.

Electrosynthesis and electrochromic properties of poly(amide-triarylamine)s containing triptycene units

Redox-active and electrochromic films of poly(amide-triarylamine)s with triptycene units have been directly fabricated on the electrode surface via the electrochemical oxidative coupling of triphenylamine or carbazole units.