Synthetic-polymer-assisted antisense oligonucleotide delivery: targeted approaches for precision disease treatment

• Ana Cubillo Alvarez,
• Dylan Maguire and
• Ruairí P. Brannigan

Beilstein J. Nanotechnol. 2025, 16, 435–463, doi:10.3762/bjnano.16.34

• of cysteine-PNAs via disulfide linkage [126]. These compounds showed a PNA dose-dependent cell toxicity and exhibited up to almost 20-fold increased luciferase activity compared to free arginine-PNAs and dithiothreitol control. In another study, Kuhn et al. developed aminoethylene-based PMO

Nanoarchitectonics with cetrimonium bromide on metal nanoparticles for linker-free detection of toxic metal ions and catalytic degradation of 4-nitrophenol

• Akash Kumar and
• Raja Gopal Rayavarapu

Beilstein J. Nanotechnol. 2024, 15, 1312–1332, doi:10.3762/bjnano.15.106

• sections, NaOH plays a significant role in decreasing the amount of CTAB on the nanoparticles, thus providing binding sites to the metal ions. The interaction with Hg2+ was also evident in as-prepared and centrifuged CTAB-AgNS. Placido et al. demonstrated Hg2+ detection using ʟ-cysteine-functionalized CTAB

• crucial regarding nanorod–metal interactions. In a previous study conducted by Xu et al., Cu2+ was detected with cysteine-functionalized CTAB-AuNR (λmax 800 nm), while Hg2+ was detected with cysteine-functionalized CTAB-AuNR (λmax 650 nm) [50][52]. Both ʟ-cysteine-functionalized CTAB-AuNR detected

Interaction of graphene oxide with tannic acid: computational modeling and toxicity mitigation in C. elegans

• Romana Petry,
• James M. de Almeida,
• Francine Côa,
• Felipe Crasto de Lima,
• Diego Stéfani T. Martinez and
• Adalberto Fazzio

Beilstein J. Nanotechnol. 2024, 15, 1297–1311, doi:10.3762/bjnano.15.105

• biosynthesis protein COQ7 [51][53][54][55]. The co-exposure of GO with antioxidant molecules, such as ʟ-cysteine and ascorbate, can mitigate the oxidative effects of the material and minimize GO’s toxicity [35][53]. Moreover, GO also shows important neuronal effects; for example, it influences protein–protein

Realizing active targeting in cancer nanomedicine with ultrasmall nanoparticles

• André F. Lima,
• Giselle Z. Justo and
• Alioscka A. Sousa

Beilstein J. Nanotechnol. 2024, 15, 1208–1226, doi:10.3762/bjnano.15.98

• inorganic core, exemplified by the S–Au bond formed between cysteine-containing molecules and gold NPs [90][91][92]. Actively targeted AuNCs can also be prepared using bioactive peptides or proteins via a one-step biomineralization process, in which case the peptide or protein serves the purpose of both

Recent updates in applications of nanomedicine for the treatment of hepatic fibrosis

• Damai Ria Setyawati,
• Fransiska Christydira Sekaringtyas,
• Riyona Desvy Pratiwi,
• A’liyatur Rosyidah,
• Rohimmahtunnissa Azhar,
• Nunik Gustini,
• Gita Syahputra,
• Idah Rosidah,
• Etik Mardliyati,
• Tarwadi and
• Sjaikhurrizal El Muttaqien

Beilstein J. Nanotechnol. 2024, 15, 1105–1116, doi:10.3762/bjnano.15.89

• targeting activated HSCs. The presence of HSA on the surface of the nanocrystals may facilitate active targeting to activated HSCs via secreted protein acidic and rich in cysteine (SPRAC)-mediated endocytosis. It was reported that the activated HSCs overexpressed SPRAC, which is known as classic albumin

Simultaneous electrochemical determination of uric acid and hypoxanthine at a TiO₂/graphene quantum dot-modified electrode

• Vu Ngoc Hoang,
• Dang Thi Ngoc Hoa,
• Nguyen Quang Man,
• Le Vu Truong Son,
• Le Van Thanh Son,
• Vo Thang Nguyen,
• Le Thi Hong Phong,
• Ly Hoang Diem,
• Kieu Chan Ly,
• Ho Sy Thang and
• Dinh Quang Khieu

Beilstein J. Nanotechnol. 2024, 15, 719–732, doi:10.3762/bjnano.15.60

• stability of the (1:4)TiO2/QGDs-GCE (Figure 9d). In order to study the selectivity of the (1:4)TiO2/GQDs-modified electrode, common co-existing substances, namely, NH4Cl, KCl, Na2SO4, NH4NO3, CaCl2, ZnCl2, glucose (GLC), glutamic acid (GLA), urea (URE), ʟ-cysteine (LCY) and xanthine (XTE), have been added

Antibody-conjugated nanoparticles for target-specific drug delivery of chemotherapeutics

• Mamta Kumari,
• Amitabha Acharya and
• Praveen Thaggikuppe Krishnamurthy

Beilstein J. Nanotechnol. 2023, 14, 912–926, doi:10.3762/bjnano.14.75

• the reduction of disulfide bonds. Thiols, also called sulfhydryls, in the cysteine side chain are slightly less abundant than primary amines; therefore, the coupling by thiol groups is more selective [52]. Thiols in cysteines are linked by disulfide bonds (–S–S–) through an oxidation process where the

• thiols groups are oxidized into disulfides. The disulfide bonds stabilize tertiary and quaternary protein structures and play a crucial role in protein folding [53][54]. For conjugation, free thiol and reduced thiol groups are required. Many proteins contain cysteine moieties linked with thiol. In

• proteins that do not have free thiol groups, such groups can be generated either by reducing the disulfide bonds (DTT and BME) or by introducing cysteine residues (Traut’s reagent and N-succinimidyl S-acetylthioacetate) at different positions. The reaction with primary amines or the reduction of disulfide

Cyclodextrins as eminent constituents in nanoarchitectonics for drug delivery systems

• Makoto Komiyama

Beilstein J. Nanotechnol. 2023, 14, 218–232, doi:10.3762/bjnano.14.21

• enhances the hydrophobic interactions of the poly(N-isopropylacrylamide) segments, stabilizing the hydrogel. The anticancer drug DOX encapsulated in the hydrophobic core is slowly released through the dissolution of the hydrogel to micelles. By modifying β-CyD with both N-acetyl-ʟ-cysteine and arginine

• , insulin was orally delivered [98]. N-Acetyl-ʟ-cysteine enhances the mucoadhesion of the drug to enhance its biological absorption, whereas arginine promotes the intestinal absorption of insulin. The composite was sufficiently water-soluble and applicable to the oral delivery of insulin, which is mostly

Photoelectrochemical water oxidation over TiO₂ nanotubes modified with MoS₂ and g-C₃N₄

• Phuong Hoang Nguyen,
• Thi Minh Cao,
• Tho Truong Nguyen,
• Hien Duy Tong and
• Viet Van Pham

Beilstein J. Nanotechnol. 2022, 13, 1541–1550, doi:10.3762/bjnano.13.127

• fluoride (NH4F), N-acetyl-ʟ-cysteine, ammonium heptamolybdate ((NH4)6Mo7O24), thiourea (CH4N2S), nitrogen gas, melamine, and nafion solution. All chemicals and materials were purified and used without further treatment. Preparation of materials The individual materials including TNAs, MoS2, and g-C3N4 were

Near-infrared photoactive Ag-Zn-Ga-S-Se quantum dots for high-performance quantum dot-sensitized solar cells

• Roopakala Kottayi,
• Ilangovan Veerappan and
• Ramadasse Sittaramane

Beilstein J. Nanotechnol. 2022, 13, 1337–1344, doi:10.3762/bjnano.13.110

• (GaCl3), sulfur powder (S), 1-dodecanethiol (DDTh), ʟ-cysteine, copper(II) chloride, polyvinylidene fluoride (PVDF), titanium isisopropoxide (TIP), glycerol, oleylamine (OAM), titanium tetrachloride (TiCl4), N-methyl-2-pyrrolidine (NMP), chloroform, acetonitrile, ethanol, and methanol were purchased from

• [2][19][20]. Hence, in this work Cu2S was chosen as the CE material. The CE was fabricated as described in [8]. At first, Cu2S NPs were prepared by a hydrothermal method using ʟ-cysteine and copper(II) chloride. Then the Cu2S paste containing 95% of Cu2S and 5% of PVdF in NMP was coated onto FTO

Design of surface nanostructures for chirality sensing based on quartz crystal microbalance

• Yinglin Ma,
• Xiangyun Xiao and
• Qingmin Ji

Beilstein J. Nanotechnol. 2022, 13, 1201–1219, doi:10.3762/bjnano.13.100

• MOFs. Yang et al. reported the fabrication of chiral UiO-MOF-derived QCM sensors for efficient discrimination of cysteine (Cys) enantiomers (Figure 8), of which the ʟ-type is vital in biological processes but the ᴅ-type has a hazardous effect [100]. The chiral UiO-MOF sensors (ʟ- and ᴅ-UiO-tart) were

• structure. The research group also prepared chiral Al2O3 films by a similar process using SAMs of cysteine (Cys) and KAl2(AlSi3O10)(OH)2 precursors (Figure 10) [121]. The resultant Al2O3 films were efficiently deposited on the SAMs and formed a very smooth and conformal film with a thickness of (8.9 ± 0.1

• of metal-based chiral sensing applications. Based on surface modification or induced crystallization, metal nanostructures may bear chiral surfaces for chiral sensing of enantiomers. For example, Zhang et al. achieved chiral recognition of cysteine enantiomers using nucleotide-modified Ag

Recent advances in green carbon dots (2015–2022): synthesis, metal ion sensing, and biological applications

• Aisha Kanwal,
• Naheed Bibi,
• Sajjad Hyder,
• Arif Muhammad,
• Hao Ren,
• Jiangtao Liu and
• Zhongli Lei

Beilstein J. Nanotechnol. 2022, 13, 1068–1107, doi:10.3762/bjnano.13.93

• groups react with EDA to increase the QY and with dodecyl amine (DDA) to obtain CDs dispersible in polar solvents [91]. CDs doped with nitrogen and sulfur (N,S-CDs) were synthesized using rose petals as a natural precursor, and ʟ-cysteine and EDA as N and S dopants, respectively, by Sharma et al

• . Cysteine and EDA help in hydrolysis and dehydration, respectively, which are part of the bottom-up approach. After completion of aromatization, the N,S-doped CDs are made from nuclear bursts [5]. Pal et al. used branched-chain PEI (bPEI) as a surface passivator and curcumin as a green precursor to

• with a calculated fluorescence QY of 10.6% were also reported, which were found to selectively detect Fe3+ ions. These N-CDs/Fe3+ systems could be used to sense cysteine, based on fluorescence “turn on” effects (see below Figure 9). The reported N-CDs showed temperature-dependent fluorescence behavior

Bioselectivity of silk protein-based materials and their bio-inspired applications

• Hendrik Bargel,
• Vanessa T. Trossmann,
• Christoph Sommer and
• Thomas Scheibel

Beilstein J. Nanotechnol. 2022, 13, 902–921, doi:10.3762/bjnano.13.81

• to 75–83 wt % of raw silkworm silk, while sericins, hydrophilic proteins forming a connective coating, constitute 17–25% of the weight of the fibre. Fibroins contain very few cysteine residues, whereas glycine, alanine, serine, and tyrosine make up more than 90 mol %. The fibroins largely contain

Detection and imaging of Hg(II) in vivo using glutathione-functionalized gold nanoparticles

• Gufeng Li,
• Shaoqing Li,
• Rui Wang,
• Min Yang,
• Lizhu Zhang,
• Yanli Zhang,
• Wenrong Yang and
• Hongbin Wang

Beilstein J. Nanotechnol. 2022, 13, 549–559, doi:10.3762/bjnano.13.46

• through the interaction between covalent and non-covalent bonds due to the smaller steric hindrance [23][24][25]. The surface of GNPs can be modified by Au–S bonds with molecules containing thiol groups, such as cysteine [26][27][28], 3-mercaptopropionic acid [29], and homocysteine [30]. Also, they easily

• conjugate with drug molecules and fluorescent dyes [24]. Recently, we developed a novel Cu(II)-triggered release system with gold nanoparticles surface-modified with ʟ-cysteine for molecular delivery and imaging in cells [31]. Well dispersed GNP–ʟ-cysteine was conjugated with Rh6G2 (GNP–ʟ-Cys–Rh6G2) for a

Coordination-assembled myricetin nanoarchitectonics for sustainably scavenging free radicals

• Xiaoyan Ma,
• Haoning Gong,
• Kenji Ogino,
• Xuehai Yan and
• Ruirui Xing

Beilstein J. Nanotechnol. 2022, 13, 284–291, doi:10.3762/bjnano.13.23

• , cysteine, and glutamic acid. The cysteine residue plays a pivotal role in protecting the body from oxidation damage; however, GSH is easily metabolized by enzymes [23]. In this work, we employed a facile co-assembly strategy to design hybrid nanoparticles as antioxidants [24][25][26][27][28][29][30][31

Self-assembly of amino acids toward functional biomaterials

• Huan Ren,
• Lifang Wu,
• Lina Tan,
• Yanni Bao,
• Yuchen Ma,
• Yong Jin and
• Qianli Zou

Beilstein J. Nanotechnol. 2021, 12, 1140–1150, doi:10.3762/bjnano.12.85

• cells [38]. Gour et al. explored the self-assembly of nonaromatic amino acids. They first reported the ability of nonaromatic single amino acids, cysteine and methionine, to spontaneously self-assemble to form protein-like aggregates, which are very long and fibrous and may be cytotoxic to human

Fate and transformation of silver nanoparticles in different biological conditions

• Barbara Pem,
• Marija Ćurlin,
• Darija Domazet Jurašin,
• Valerije Vrček,
• Rinea Barbir,
• Vedran Micek,
• Raluca M. Fratila,
• Jesus M. de la Fuente and
• Ivana Vinković Vrček

Beilstein J. Nanotechnol. 2021, 12, 665–679, doi:10.3762/bjnano.12.53

• was studied in the presence of the most relevant biothiols: cysteine (CYS) and glutathione (GSH). Data on the size distribution of different AgNPs in the tested media are given in Figure 5 and in Supporting Information File 1, Table S1, while observed ζ potentials are presented in Figure 6 and in

Characterization, bio-uptake and toxicity of polymer-coated silver nanoparticles and their interaction with human peripheral blood mononuclear cells

• Sahar Pourhoseini,
• Reilly T. Enos,
• Angela E. Murphy,
• Bo Cai and
• Jamie R. Lead

Beilstein J. Nanotechnol. 2021, 12, 282–294, doi:10.3762/bjnano.12.23

• . RPMI medium contains chloride, which can lead to reprecipitation of Ag ions as described previously [37]. Furthermore, cysteine and thiol-containing proteins are found in FBS and have a high affinity for Ag ions and NPs. Ag loss to the container wall could be another reason that we did not get full

Straightforward synthesis of gold nanoparticles by adding water to an engineered small dendrimer

• Sébastien Gottis,
• Régis Laurent,
• Vincent Collière and
• Anne-Marie Caminade

Beilstein J. Nanotechnol. 2020, 11, 1110–1118, doi:10.3762/bjnano.11.95

• amino acids such as ʟ-histidine, which have been used to synthesize gold nanoparticles at a higher temperature (80 °C) [49], or cysteine [50]. The compound 1 was the dendrimer chosen for the functionalization with the Girard’s T reagent. The synthesis was performed via the Staudinger reaction between

Identification of physicochemical properties that modulate nanoparticle aggregation in blood

• Ludovica Soddu,
• Duong N. Trinh,
• Eimear Dunne,
• Dermot Kenny,
• Giorgia Bernardini,
• Ida Kokalari,
• Arianna Marucco,
• Marco P. Monopoli and
• Ivana Fenoglio

Beilstein J. Nanotechnol. 2020, 11, 550–567, doi:10.3762/bjnano.11.44

• were sequentially isolated and fragmented by higher-energy C-trap dissociation. MS raw files were processed with MaxQuant software (version 1.6.2). The peak lists were searched against the human FASTA database. The search included the modifications of cysteine carbamidomethylation, methionine oxidation

Luminescent gold nanoclusters for bioimaging applications

• Nonappa

Beilstein J. Nanotechnol. 2020, 11, 533–546, doi:10.3762/bjnano.11.42

• imaging [91]. Recently Duan et al. reported the synthesis of NIR-luminescent AuNCs capped with N-acetyl-ʟ-cysteine (NAC-CS) for long-time imaging [92]. The Au-NAC-CS NCs were insensitive to hydrogen peroxide and trypsin in contrast to Au NCs coated with BSA or other proteins, allowing for extended imaging

Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery

• Varsha Sharma and
• Anandhakumar Sundaramurthy

Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41

• cell line showed a rapid uptake, demonstrating the potential for cancer therapy. Silica and gold NPs were assembled in a one pot assembly of specifically tailored diblock polymers of PLL and poly-ʟ-cysteine [82]. The electrostatic binding between the positively charged lysine blocks and negatively

• charged silica NPs as well as the disulfide linkages between cysteine blocks and gold NPs resulted in two types of functionalities in the capsule. In a similar way, the capsules incorporated with noble metal NPs (e.g., gold and silver) respond to external light illumination by increased surface plasmon

• use of UV light in the thiol-ene approach limits its application in drug delivery as it can damage DNA and cross-react with cysteine residues in proteins. The DAC approach may also affect cysteine residues in proteins that might undergo Michael addition to result in malemides [90]. Similarly, the use

Rational design of block copolymer self-assemblies in photodynamic therapy

• Maxime Demazeau,
• Laure Gibot,
• Anne-Françoise Mingotaud,
• Patricia Vicendo,
• Clément Roux and
• Barbara Lonetti

Beilstein J. Nanotechnol. 2020, 11, 180–212, doi:10.3762/bjnano.11.15

• disulfide bonds has been proposed for stabilization. Li et al. [87] proposed telodendrimers formed by linear polyethylene oxide and pheophorbide a and cholic acid at the ends of dendritic polylysine. The insertion of four cysteine mioeties in the oligolysine backbone allowed for a stabilization of the

Internalization mechanisms of cell-penetrating peptides

• Ivana Ruseska and
• Andreas Zimmer

Beilstein J. Nanotechnol. 2020, 11, 101–123, doi:10.3762/bjnano.11.10

Bombesin receptor-targeted liposomes for enhanced delivery to lung cancer cells

• Mohammad J. Akbar,
• Pâmela C. Lukasewicz Ferreira,
• Melania Giorgetti,
• Leanne Stokes and
• Christopher J. Morris

Beilstein J. Nanotechnol. 2019, 10, 2553–2562, doi:10.3762/bjnano.10.246

• vivo cancer imaging. In this report we decorated pegylated liposomes with a GRPR antagonist peptide and studied its interaction with, and accumulation within, lung cancer cells. Results: An N-terminally cysteine modified GRPR antagonist (termed cystabn) was synthesised and shown to inhibit cell growth

• structure was modified to bear an N terminal ʟ-cysteine residue, which enables subsequent attachment to a functionalised lipid carrier. The peptide, hereafter termed cystabn, was prepared by fluorenylmethoxycarbonyl (Fmoc) solid-phase peptide synthesis and characterised by HPLC and mass spectrometry (data

• not shown). To confirm the persistent functionality of the peptide after cysteine addition, NCI-H345 cells were exposed to escalating concentration of Tyr4-Bn and cystabn in serum-free conditions. As expected, Tyr4-Bn resulted in a scalable increase (p < 0.05) in cell number as judged by MTS assay