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26/11/2018 Review Form Response

http://aij.batan.go.id/index.php/aij/sectionEditor/viewReviewFormResponse/745/998 1/3

REVIEW FORM RESPONSE

Referee's Report >>

1. The Title is Appropriate * [2] Partly Correct

Comment

Radiolabelling Technique of Silver Nanoparticles (AgNPs) with Iodine-131 Radionuclide

2. Abstract

The Content and Length of the abstract are appropriate * [2] Partly Correct

Comment

Need to be re-written

3. Main Text

The results are important to be reported * [2] Partly Correct

Comment

See attachment

The paper is of high scientific quality (scientifically sound) * [2] Partly Correct

Comment

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The paper is well organized (experimental/theory/results/conclusion) * [2] Partly Correct

Comment

See attachment

The length of the paper is appropriate to the content * [1] Completely Correct

Comment

The references are adequate in complete / consist of 85% primary references and recent journals *

[1] Completely Correct Comment

The English is alright * [2] Partly Correct

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Comment

See Attachment

Final Comments

To the Author *

This paper need to be re-written as this paper has not been well structured and has a contradiction between statement

Confidential Comments to the EIC

This Paper is recommended to be * Accepted without further revision Accepted with minor revision Major Revision is required Rejected

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ATOM INDONESIA JOURNAL

Referee’s Report

Article No. : # 745

Title of Paper :

Radiolabelling Technique of Silver Nanoparticles (AgNPs) with Iodine-131 Radionuclide

Line # Referee’s Comments

12-13

There is a contradiction between statement

Radiotherapy is an effective cancer therapy, specific to target but unaffected to normal tissue. To overcome this issue, radioactive is attached to a carrier targeting specific organ.

1^st Paragraph 15 – 36

“In an academic/ scientific essay, the purpose of a paragraph is to support a single claim or idea that helps establish the overall argument or purpose of the paper.

Paragraphs should be focused around this single idea or point, and

they should be clearly related to what comes before them”

In this paragraph there are three different ideas which are nanomedicine, application of radiopharmaceutical and PET.

Paragraph 1 is supposed to discuss only single claim or idea.

So it is suggested in the first paragraph you only discuss about what is radiopharmaceutical, diagnostic and therapeutic radiopharmaceuticals. What is an ideal radiopharmaceuticals for targeted therapy

2^nd -3^rd paragraph

In this paragraph you may discuss about nanomedicine agent and nano particle, silver nanoparticle (AgNPs ).

Once AgNPs has been introduced….just used AgNPs in further discussion

4^rd paragraph

In this paragraph you may discuss why:

1. radiolabelled silver nanoparticle might be good for targeted radiopharmaceutical agent.

2. What you are going to do with silver nanoparticle

Four paragraphs for introduction should be sufficiently enough to introduce your presented work

Experimental methods

111- 138

1. Do not write chemical name in capital except in the beginning of a sentence.

2. Pool all chemicals from the same manufacture and put manufacture’s name in the bracket, such a, b, c and d (Sigma-Aldrich)

3. Do not write instrument name in capital except in the beginning of a sentence, brand or model.

135 - 138

Radiolabeling of AgNPs with ¹³¹I was carried out in 3 steps: a) scaled synthesis of AgNPs and its purification, b) radiolabeling AgNPs using ¹³¹I and c) quality control of AgNPs -¹³¹I product.

140 - 154

Scale up synthesis of AgNPs its Purification

The synthesis method of AgNPs referred to Sholikhah et. al. [12] with some modification. The synthesis was scaled with multi-steps of purification step. “Write

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here how AgNPs is synthesised”. Purification of AgNPs was done by centrifugation at 12,210 rpm for 30 minutes at 4 °C. The pellet was then taken out and re-

suspended with 400 µL phosphate buffer pH 7, followed by centrifugation at 8000 rpm for 15 minutes at 4 ^°C [13]. The produced AgNPs were analyzed using UV-Vis spectrophotometer for optical properties, TEM for particle size and morphology, PSA for particle size distribution and Zeta-sizer for zeta potential measurement.

o

Measurement of Radionuclide and Radiochemical Purityof ¹³¹I

The parameters are radionuclide and radiochemical purity. Radionuclide purity of Na-¹³¹I

131 I were measured using gamma ray spectrometer. Each sample was adsorbed on a rounded Whatman 1 filter paper, then added to the spacer and the energy was detected.

156- 167

Radiolabeling AgNP with ¹³¹I

Immobilization of Chloramine-T on glass beads by performed by immersing 1 gram glass bead in 5 mL of 0.0005 M Chloramine-T for 30 min. The glass beads were separated into a clean vial. A solution of Na-¹³¹I (500 µL) was measured for its radioactivity using dose calibrator then added into a vial which contained

immobilized of Chloramine-T glass beads (??) and allowed to react for 10 minutes.

The solution of ¹³¹1 (???) which has been oxidised, was then transferred into a vial containing 1 mL of AgNP. The mixture allowed to react for 30 minutes at room temperature. Radioactivity of AgNPs-131I activity was then measured dose calibrator.

Note: Is there any purification step performed in this preparation???

171- 195

AgNPs-131I Quality Control

The quality control for AgNP-I is important parameter in order to estimate the radiolabeled compound (AgNP-¹³¹I) formed. Radiochemical purity determined by using thin layer chromatography (TLC) where Whatman paper No. 1 strip (1 cm x 17 cm) used as stationary phase and a mixture of methanol: water: ammonium acetate (1: 1: 1, v:v:v) used as a mobile phase. A drop (5 L) of AgNPs-131I was spotted to Whatman paper No. 1 strip and was dried. The chromatographic strip was developed, dried, then measured for its radioactivity distribution using a gamma counter. This procedure is also performed for Na-¹³¹I bulk as a standard in measuring the percentage of free Na-¹³¹I (or Na-¹³¹I not attached to AgNPs).

Note:

Radionuclide and radiochemical purity tests of ¹³¹I has to be performed before radiolabeling of AgNP with ¹³¹I. So you need a new paragraph just before a paragraph of Radiolabeling AgNP with ¹³¹I

198- 226

The preparation of AgNPs have been performed (???) (See note) by chemical reduction method. In this research, sodium borohydride was used as a strong reducing agent which aimed to produce the well-controlled size of AgNPs. The mechanism of nanoparticle formation using sodium borohydride could be expressed as follows [14]:

In AgNPs synthesis, PVP should be added first which then followed by addition of NaCl. The additions of PVP without NaCl resulted in aggregation because PVP act as a stabilizer. Addition of NaBH⁴ into a AgNO3 solution in order to reduce Ag⁺

become Ag which is followed by color changes from colorless to yellow which conforms to a result reported byYena et. al. [15]. In this reaction of AgNO3 is reduced by NaBH4. The mole ratio of reducing agent towards AgNO³has to be proportional. If the mole ratio of reducing agent is insufficient, it cannot reduce all the available silver. However, when mole of NaBH4 in an excess, it can cause an ion release in the solution which in turn will form nanoparticles with higher

hydrodynamic diameter and aggregation [16]. The mole ratio in this study, NaBH4 :

AgNO3 = XX : XXX, was found to be the best for reduction processes which resulted

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AgNPs suitbale to be radiolabelled with ¹³¹I. The AgNPs synthesis without addition of NaCl will resulted in an aggregation and then followed by precipitation when AgNPs re-suspended with phosphate buffer pH 7.

Line 227 -230 should be added to this paragraph.

Has been explored???. What do you mean by this? Do you use several reducing agents in this procedure? If only one type reducing agent you do not need to say it as explore…just use performed, done or other synonym.

227 - 252

The colloidal solution of AgNPs was found to give maximum absorption at the wavelength of about 397 nm on the 1^st day (just after purification) as surface plasmon resonance (SPR) of AgNP. This maximum absorption shifted to the longer

wavelength of 398 nm on day 8 after purification. This wavelength shift was found not to be significant. [Please indicate what is the wavelength shift would be

categorized as significant??]. This indicates that the AgNPs were stable as there was no change of color and aggregation for 7 days as shown at Fig. 1. This stability exceeds the half-life of radionuclide ¹³¹I so as to allow for the labeling process with the radionuclides. Stable AgNPs is one of important factors in order to have a stable radiolabeled AgNPs (AgNPs-¹³¹I). According to the previous study, UV-Vis spectra recorded for biosynthesized of AgNPs were between 350 and 450 nm [What was its peak] [17]. In this research too, the results of UV-Vis spectra indicate the increase of surface plasmon vibrations at about 390 nm wavelength.

248- 252 255- 264

This paragraph need to be moved to next paragraph.

Transmission electron microscopy data indicated that AgNPs size was below 10 nm [18] as shown in Fig. 2. The morphological form, size, stability of AgNPs is affected by experimental conditions, kinetic interactions of metal ions and the nanoparticles (NPs) adsorption with stabilizers [4].

287-302

The particle size analysis of AgNPs gave a polydispersity index value of 0.455. The polydispersity index which has a value below 0.5 indidicates that the AgNPs were quite homogeneous. NPs could be called completely homogeneous when the index value of polydispersity is close to zero. The actual size of the synthesized-AgNPs is shown in Fig. 3. It can be seen from Fig. 3 the diameter by volume (Dv) of AgNPs, where the value of Dv10, Dv50 and Dv90 are 1.52, 3.79 nm and 7.65 nm

respectively. It means as much as 10, 50 and 90% of the total particle has a size below 1.52, 3.79 and 7.65 nm respectively. This corresponds to the TEM results which show that the AgNP size is below 10 nm.

311-322

Radiolabeling of AgNPs using Radionuclide I ¹³¹

A total 320 Ci/mL of the 131 I solution which was incubated with immobilised Chloramine-T was used for labeling of AgNPs. The resulted AgNPs-¹³¹I solution is a clear yellow solution as shown at Fig. 4. The color of AgNPs before and after radiolabeling with ¹³¹I were found to be similar. This indicates that AgNPs- I is still stable without any aggregation. The AgNPs- I radioactivity was measured using the Dose Calibrator, and the result was 96.5 µCi/mL. Fig.4. AgNPs-131I sample.

Note: for Figure 4. You should also show AgNPs prior radiolabeling

329-343

Note: Radionuclide purity test result of ¹³¹I has to be discussed prior radiolabeling of AgNPs. Once Radionuclide purity test result of ¹³¹I has been found it is not

neccessary to mesure the radionuclide purity of AgNPs-¹³¹I . So, this paragraph needs to be re-written!!!

Radionuclide Purity Test of Na-I Bulk and AgNP-131 I

Based on gamma ray spectrometer analysis shows that Na-¹³¹I bulk and the AgNPs-

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131I have the same energy as listed in Table 1. Both Na-I bulk and the AgNPs-131I have same energies but the count results are decrease. It means silver nanoparticle labelled Iodine-131. As shown at Fig. 5 a and b, the AgNPs-131I sample has more than 99.9% radionuclide purity (by gamma ray spectrometer) without other radionuclide impurities. This result complies with the radiopharmaceutical requirement for radionuclidic purity which must be = 99.9 % [19]. ¹³¹

131

131 131

383-413

This paragraph needs to be given a title of “Radiochemical purity test of AgNPs-131 I . This paragraph needs to be re-written!!! Please compare the result with other if there were any.

Radiochemical purity of of AgNPs-131 I was measured by...

The Iodine-131 bulk and radiolabeling results are presented in Fig. 6 a and b. The results of the Iodine-131 bulk and radiolabeled compound AgNPs-131I show different migration. The radionuclide 131I sample has retention factor (Rf) = 0.6, while the AgNPs-131I has Rf = 0. Based on peak chromatogram in fig 6.a, the Iodine-131 shows as I form. The radiochemical purity of 131I as the raw material was 98.42% and the product AgNPs-I was 96.49%. These parameters (radionuclidic and radiochemical purity) are important to comply with radiopharmaceutical standard [20].

Fig. 6. Radiochromatogram of 131

I (a) and AgNPs- I (b).

CONCLUSION

Synthesis of an AgNPs has been succesfully perfomed by XXXX. The synthesed AgNPs have spherical shape, the diameter was below 10 nm, and zeta potential value was -8 mV. The AgNPs then radiolabeled with 131I through chemisorption method to result in AgNPs-131 with radiochemical purity of xx%.