Virus-like Cage Hybrid: Covalent Organic Cages Attached to Metal Organic Cage
Round 1
Reviewer 1 Report
Presented paper is devoted to the UpToDate field of metal-organic frameworks. The authors did a great job constructing a COC-MOF hybrid containing organic cage with long alkyl side chains. The latter facilitated solubility of final product allowing the solution study. The final structure indeed resembles virus (specifically corona virus). The synthesis of such macromolecules is a state of art itself, thus I believe this paper will be of particular interest to wide readership of “Chemistry”. However, there is some minor criticism:
Structures at figure 1 are not visually appealing. I recommend redrawing it so the ring will be in plane. Single bonds intersection is fine, but this side view of rings is rather not. Also, it is not clear why Scheme 1 is scheme but Figure one is not. While it is also technically scheme.
There is no UV-VIS data provided. Is the product colourful in solution? Is there any colour change upon formation of complex? If possible, I would recommend doing UV-Vis measurements.
Based on above mentioned I believe this paper can be accepted after minor revision.
Author Response
Reviewer 1 Presented paper is devoted to the UpToDate field of metal-organic frameworks. The authors did a great job constructing a COC-MOF hybrid containing organic cage with long alkyl side chains. The latter facilitated solubility of final product allowing the solution study. The final structure indeed resembles virus (specifically corona virus). The synthesis of such macromolecules is a state of art itself, thus I believe this paper will be of particular interest to wide readership of “Chemistry”. However, there is some minor criticism:
Point 1: Structures at figure 1 are not visually appealing. I recommend redrawing it so the ring will be in plane. Single bonds intersection is fine, but this side view of rings is rather not. Also, it is not clear why Scheme 1 is scheme but Figure one is not. While it is also technically scheme.
Response 1: Thanks for your advice. We redrew the cage structures in figure 1 carefully so the ring were in plane. And we have changed figure 1 into scheme 2.
Point 2: There is no UV-VIS data provided. Is the product colourful in solution? Is there any colour change upon formation of complex? If possible, I would recommend doing UV-Vis measurements.
Response 2: Many thanks for your comments. There is no obvious color change upon formation of complex. We conducted UV-Vis measurements of the product in Figure S10 in SI.
Reviewer 2 Report
The overall experiments are clearly represented, although the manuscript lacks novelty. A few issues:
1) What is the point of designing and preparing such a virus-like cage despite the vague resemblance? Did the author try to investigate its host-guest properties and 'practical applications'?
2) Since the authors characterize the ligand with MALDI-TOF MS. I wonder if the authors can provide MS for cage too.
3) Line 175, '0.6 nm and 3.6 nm with narrow polydispersity', polydispersity index (PDI) should be provided to substantiate this claim.
4) Line 182, 'probably' may not be a suitable word here.
Author Response
Reviewer 2 The overall experiments are clearly represented, although the manuscript lacks novelty. A few issues:
Point 1: What is the point of designing and preparing such a virus-like cage despite the vague resemblance? Did the author try to investigate its host-guest properties and 'practical applications'?
Response 1: Thanks for your comments. The construction of atomically precise nanoobjects with well-defined chemical and spatial structures is a fundamental and important topic in chemical science. Precise cage hybrid combining COC and MOC is more complex nanoobject to give full play to their respective advantages. In this research we chose the well-known Fujita sphere with general formula PdnL2n as MOC to construct virus-like cage hybrid as a continuation of our former work. We tried the host-guest interaction of this virus-like cage hybrid with atomic compounds. However, there is no obvious interactions.
Point 2: Since the authors characterize the ligand with MALDI-TOF MS. I wonder if the authors can provide MS for cage too.
Response 2: Thanks for your suggestions. We have tried several types of MS testing, such as FT-ICR-MS, ESI-MS and CSI-MS. But unfortunately, it was very difficult to obtain data with high quality due to the disadvantageous reasons below. Firstly, the giant structure of the cage hybrid, with a theoretical molecular mass of 31754.66, is positively charged, which will make traditional MALDI-TOF MS, often used to test supramolecular structures with good compatibility with substrate, unavailable to the special cage. What’s more, the relatively weak Pd-N coordination bond also makes the cage hybrid not stable enough to bear MS.
Point 3: Line 175, '0.6 nm and 3.6 nm with narrow polydispersity', polydispersity index (PDI) should be provided to substantiate this claim.
Response 3: Many thanks for your suggestion. The PDI have been carefully added to DLS analysis.
Point 4: Line 182, 'probably' may not be a suitable word here.
Response 4: Thanks for your advice. We have changed ‘probably’ into ‘was supposed to be’.
