Journal: Journal of controlled release : official journal of the Controlled Release Society

Article Title: Microfluidic formulation, cryoprotection and long-term stability of paclitaxel-loaded π electron-stabilized polymeric micelles.

doi: 10.1016/j.jconrel.2024.08.041

Figure Lengend Snippet: Fig. 3. In-situ freezing microscopy of [mPEG-b-p(HPMAm-Bz)]-based polymeric micelles with and without cryoprotectants. A) Fluorescence microscopy images of dry ice-induced in-situ freezing of Cy7-labelled mPEG-b-p(HPMAm-Bz) micelles before, during freezing (frozen) and after thawing (thawed), in the absence (without) and presence of cryoprotectants (sucrose or trehalose). B) Cryogenic-scanning electron microscopy (cryo-SEM) of frozen fractured mPEG-b-p(HPMAm-Bz) micelles (green arrows) in the presence of sucrose (orange arrow) or trehalose (purple arrow) compared to non-cryoprotected micelles (without). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Article Snippet: Cyanine 7-amine (Cy7) dye was ordered from Lumiprobe (Germany).

Techniques: In Situ, Microscopy, Fluorescence, Electron Microscopy

Journal: Investigative Ophthalmology & Visual Science

Article Title: Extended Intravitreal Rabbit Eye Residence of Nanoparticles Conjugated With Cationic Arginine Peptides for Intraocular Drug Delivery: In Vivo Imaging

doi: 10.1167/iovs.18-24087

Figure Lengend Snippet: Synthetic steps in forming CDEX NPC. CDEX glucosyl-OH groups are activated with p-nitrophenyl chloroformate in DMSO/pyridine, polymer then isolated by EtOAc precipitation. Pyrrolidyl-PEG-peptide then displaces p-nitrophenol in DMSO to give stable, carbamate-linked peptide. Low stoichiometry Cy7 amine is included during peptide coupling, excess p-nP carbonates are then quenched by excess methoxy-PEG 4 -amine (not shown).

Article Snippet: Cyanine7 (Cy7) amine and Cy7 maleimide were from Lumiprobe (Hunt Valley, MD, USA).

Techniques: Polymer, Isolation

Journal: Investigative Ophthalmology & Visual Science

Article Title: Extended Intravitreal Rabbit Eye Residence of Nanoparticles Conjugated With Cationic Arginine Peptides for Intraocular Drug Delivery: In Vivo Imaging

doi: 10.1167/iovs.18-24087

Figure Lengend Snippet: Schematic view of CDEX peptide-conjugates (NPC) in vitreous. A hydrophobic cholesteryl domain forms the CDEX NP core. Conjugated PEG-peptides extend outwards. NP are labeled by Cy7 amine, to yield <1 Cy7/NPC. Two types of positively charged peptides were linked at 61 to 64 peptides per NP (lower loading shown for un-crowded view). NPC are immobilized in vitreous by ionic binding between l-Arg guanidinium groups (blue circles) on NPC surface and HA polymer (red circles are HA carboxylate groups).

Article Snippet: Cyanine7 (Cy7) amine and Cy7 maleimide were from Lumiprobe (Hunt Valley, MD, USA).

Techniques: Labeling, Binding Assay, Polymer

Journal: Investigative Ophthalmology & Visual Science

Article Title: Extended Intravitreal Rabbit Eye Residence of Nanoparticles Conjugated With Cationic Arginine Peptides for Intraocular Drug Delivery: In Vivo Imaging

doi: 10.1167/iovs.18-24087

Figure Lengend Snippet: UV-VIS spectrum of Cy7-CDEX-3Rpeptide conjugate. λ max of peptide tyrosine: 275 nm, λ max of Cy7: 750 nm. The peak Cy7 molar extinction is 180-fold higher than that of Tyr.

Article Snippet: Cyanine7 (Cy7) amine and Cy7 maleimide were from Lumiprobe (Hunt Valley, MD, USA).

Techniques:

Journal: Investigative Ophthalmology & Visual Science

Article Title: Extended Intravitreal Rabbit Eye Residence of Nanoparticles Conjugated With Cationic Arginine Peptides for Intraocular Drug Delivery: In Vivo Imaging

doi: 10.1167/iovs.18-24087

Figure Lengend Snippet: Loss of intraocular NPC over 6 weeks at varied zeta potential. Decay of intraocular fluorescence at 3 and 6 weeks, at and beyond postinjection day 10 (“day 0”) is seen in individual eyes injected with Cy7-tagged 3R-NPC (top row), 2R-NPC (middle row), and unconjugated NP (bottom row). Spreading and loss of fluorescence is slowed in more highly charged NPC, with correspondingly greater zeta potential.

Article Snippet: Cyanine7 (Cy7) amine and Cy7 maleimide were from Lumiprobe (Hunt Valley, MD, USA).

Techniques: Zeta Potential Analyzer, Fluorescence, Injection

Journal: Investigative Ophthalmology & Visual Science

Article Title: Extended Intravitreal Rabbit Eye Residence of Nanoparticles Conjugated With Cationic Arginine Peptides for Intraocular Drug Delivery: In Vivo Imaging

doi: 10.1167/iovs.18-24087

Figure Lengend Snippet: Loss of 3Arg NPC in a single eye over six weeks. A single exemplary eye injected with Cy7 tagged 3R-peptide conjugate is followed by IVIS over 6 weeks beyond the first scan at day 10 postinjection (“day 0”). Photon flux is registered in the rectangle above each eye, designating 800 nm photons emitted per cm 2 , within the 3.51 cm 2 circle shown around each eye. Values were corrected by subtracting the autofluorescence (photon emission of eyes before any injection), and percent of “day 0” remaining tabulated. 22% remains after 6 weeks in this eye.

Article Snippet: Cyanine7 (Cy7) amine and Cy7 maleimide were from Lumiprobe (Hunt Valley, MD, USA).

Techniques: Injection

Journal: Investigative Ophthalmology & Visual Science

Article Title: Extended Intravitreal Rabbit Eye Residence of Nanoparticles Conjugated With Cationic Arginine Peptides for Intraocular Drug Delivery: In Vivo Imaging

doi: 10.1167/iovs.18-24087

Figure Lengend Snippet: In vivo loss of NP and NPC (2R, and 3R) from rabbit vitreous over time. (A) Ex vivo calibration of photon/s emission per cm 2 in 3.51 cm 2 circles surrounding freshly enucleated rabbit eyes injected with specified amounts of Cy7 derivatives, all scans at 24 hours postinjection. Red line is 3 concentrations (n = 1) of 50 μL injected Cy7-thiopeptide. Black line is 4 concentrations (n = 2) of 100 μL injected Cy7-Dex-10. Details of these scans are shown on and indicate a constant ratio of photon flux to injected nanomoles of Cy7, validating the in vivo pharmacokinetics of Cy7-tagged NP and NPC. Ex vivo autofluorescence was <5% of the lowest Cy7 flux. (B) In vivo IVIS scans of Cy7 fluorescence for unconjugated control NP: Cy7-CDEX-0 (n = 2), carried out on day 10, 17, 24, and 31 postinjection, expressed as percent of the day 10 emission. The percent remaining after 7 days (day 17) suggests ∼5 days half-life, is complicated by transit outward from the center of the vitreous. Less than 1% of the day 10 flux was observed on days 24 and 31, implying a half-life of eye clearance <3 days. Detail of fluxes is shown on . (C) Percent remaining Cy7 fluorescence in time point in vivo IVIS scans of NPCs: Cy7-CDEX-2R (n = 3), same time points as above and; Cy7-CDEX-3R (n = 3) time points as above with an additional scan at day 52. Half-lives: Cy7-CDEX-2R 7 days; Cy7-CDEX-3R 17 days, based on one phase exponential decay analysis by graphing software (GraphPad Prism version 7; GraphPad Software, La Jolla, CA, USA). Quantitative fluorescence detail is shown on .

Article Snippet: Cyanine7 (Cy7) amine and Cy7 maleimide were from Lumiprobe (Hunt Valley, MD, USA).

Techniques: In Vivo, Ex Vivo, Injection, Drug discovery, Fluorescence, Control, Software

Journal: Investigative Ophthalmology & Visual Science

Article Title: Extended Intravitreal Rabbit Eye Residence of Nanoparticles Conjugated With Cationic Arginine Peptides for Intraocular Drug Delivery: In Vivo Imaging

doi: 10.1167/iovs.18-24087

Figure Lengend Snippet: Early clearance of IVT injected Cy7-CDEX-2R, at elevated total dose. (A) In vivo loss of Cy7-CDEX-2R from rabbit vitreous is shown as photons/s (normalized to cm 2 in 3.5 cm 2 circles) for 3 distinct doses, one being the dose (30 μL at 3 mg/mL, 90 μg total) described in C. IVIS scans were taken at day 10, 24, 31, and 38. Cy7-CDEX-2R (30 μL) was from stocks at 4 different concentrations: control, 0 mg/mL (n = 3); 3 mg/mL (n = 3); 6 mg/mL (n = 2); and 12 mg/mL (n = 2). Samples at 3 mg/mL and 6 mg/mL (180 μg total) gave proportional day 10 photons/second emission. NPC at 12 mg/mL (360 μg total dose) was much lower at the earliest scan, even below the 4X lower dose. (B) Later time points are shown as percent emission remaining compared to day 10 (taken as “day 0”, 100%). Half-life of residual NPC loss, after day 10, at the two lower doses, is similar to that observed previously. The residual loss, at the highest dose is slower.

Article Snippet: Cyanine7 (Cy7) amine and Cy7 maleimide were from Lumiprobe (Hunt Valley, MD, USA).

Techniques: Injection, In Vivo, Control