Recent progress in actuation technologies of micro/nanorobots

• Ke Xu and
• Bing Liu

Beilstein J. Nanotechnol. 2021, 12, 756–765, doi:10.3762/bjnano.12.59

• -actuation. Magdanz et al. [46] proposed to use spermatozoa containing flagella as an actuation force for the preparation of micro/nanorobots. When combining sperm cells with nanotubes, the swing of the sperm flagella interacts with the microtubes to actuate the movement of the robot. Due to the high

• motility and the safety advantages of spermatozoa compared with bacteria and other microorganisms, sperm-driven micro/nanorobots are expected to become a promising device in the field of artificial insemination and other reproductive technologies. Martel [47] found that, in previous studies, there was no

Recent progress in magnetic applications for micro- and nanorobots

• Ke Xu,
• Shuang Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2021, 12, 744–755, doi:10.3762/bjnano.12.58

• sperm cells; magnetic helical enzyme carriers for the cumulus cell removal by enzymes (e.g., hyaluronidase); artificial flagella with multiple windings and a claw-shaped sperm carrier for the delivery of immotile sperm cells; artificial flexible flagella for transport of immotile spermatozoa; stimuli

• -responsive polymeric microtubes for the delivery of motile spermatozoa; and polymeric printed microtubes for the guidance of motile sperm cells. Panels (a–c) adapted from [85], V. Magdanz et al., “Spermatozoa as Functional Components of Robotic Microswimmers”, Adv. Mater., with permission from John Wiley and

Synthesis, characterization and in vitro effects of 7 nm alloyed silver–gold nanoparticles

• Simon Ristig,
• Svitlana Chernousova,
• Wolfgang Meyer-Zaika and
• Matthias Epple

Beilstein J. Nanotechnol. 2015, 6, 1212–1220, doi:10.3762/bjnano.6.124

• reduces the amount of released silver ions. In a comparable toxicity study with laser-generated alloyed Ag/Au nanoparticles on cumulus-oocyte complexes and spermatozoa [38] and human gingival fibroblasts [39], a passivating effect of gold on silver was reported. In contrast to these studies, the toxicity

• complexes and spermatozoa, the nanoparticles showed toxic effects when the molar silver content was higher than 50%. Still, the effect was lower than the expected toxicity based on the silver content [38]. Similar results were found for human gingival fibroblasts and S. aureus [25]. For our investigations

Influence of gold, silver and gold–silver alloy nanoparticles on germ cell function and embryo development

• Ulrike Taylor,
• Daniela Tiedemann,
• Christoph Rehbock,
• Wilfried A. Kues,
• Stephan Barcikowski and
• Detlef Rath

Beilstein J. Nanotechnol. 2015, 6, 651–664, doi:10.3762/bjnano.6.66

• design of nanoparticles with increased biosafety is highly relevant for biomedical applications. Keywords: bimetallic nanoparticles, nano gold; nano silver; ontogenesis, oocyte; reprotoxicity; spermatozoa; Review Reprotoxicology Repotoxicological studies are a mandatory part during every stage of drug

• internationally standardized protocols. The period around conception is characterized by considerable cytological and molecular restructuring and is therefore particularly sensitive to disturbances. Hence, otherwise subtle effects can be detected more easily. Furthermore, oocytes and spermatozoa possess very

• articles per year were published concerning nanotoxicology in general, only 3 of them concerned spermatozoa and 2 oocytes (source: web of knowledge). We are therefore unable to draw a comprehensive picture of nanoparticle reprotoxicology. However, studies concerning gold (AuNP) and silver nanoparticles

Current state of laser synthesis of metal and alloy nanoparticles as ligand-free reference materials for nano-toxicological assays

• Christoph Rehbock,
• Jurij Jakobi,
• Lisa Gamrad,
• Selina van der Meer,
• Daniela Tiedemann,
• Ulrike Taylor,
• Wilfried Kues,
• Detlef Rath and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2014, 5, 1523–1541, doi:10.3762/bjnano.5.165

• presence of gold nanoparticles of variable size (6 nm and 20 nm), dose (up to 9 × 1010 particles/oocyte) and surface functionalization (BSA and citrate) (Figure 13A). In accordance with these findings spermatozoa exposed to gold nanoparticles in an albumin rich medium showed no functional impairment

• . However, previous examination in this context revealed decreased motility of spermatozoa incubated with gold nanoparticles in serum-free medium. These results were associated with membrane attachment of aggregated nanoparticles blocking surface thiol groups involved in sperm movement [147], which probably

• dominating mechanism involved in nanotoxicity of these materials [82][83]. Next to the above specified examples on AuAg alloys [35][148] the applicability of ligand-free Au and Ag nanoparticles in reproduction biology was demonstrated. This includes effects on spermatozoa [147] as well as on embryo

Injection of ligand-free gold and silver nanoparticles into murine embryos does not impact pre-implantation development

• Ulrike Taylor,
• Wiebke Garrels,
• Annette Barchanski,
• Svea Peterson,
• Laszlo Sajti,
• Andrea Lucas-Hahn,
• Lisa Gamrad,
• Ulrich Baulain,
• Sabine Klein,
• Wilfried A. Kues,
• Stephan Barcikowski and
• Detlef Rath

Beilstein J. Nanotechnol. 2014, 5, 677–688, doi:10.3762/bjnano.5.80

• transfer and full development. The results for gold nanoparticles are in accordance with most previous studies using piscine, avian as well as murine embryos [13][14][26][38]. Reports stating reprotoxicological effects of gold are generally rare. Spermatozoa seem to be slightly more sensitive [63][64], but